Term
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Definition
| An abnormal breathing pattern with a sinking, inward motion of the abdomen with each inspiration caused by diaphragmatic fatigue. |
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Term
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Definition
| Any of a class of substances that yields hydrogen ions when dissolved in water; that can act as a proton donor; and can accept a pair of electrons to form a covalent bond. It can also be defined as any substance whose aqueous solutions are characterized by a sour taste, the ability to turn blue litmus paper red, and the ability to react with bases and certain metals to form salts. |
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Term
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Definition
| Acidemia is the more exact term for ABG interpretation because it refers specifically to decreased pH in the blood (plasma), but in practice acidosis is more commonly used for ABG’s. Acidosis (acidemia) can be caused by metabolic or respiratory mechanisms. Metabolic acidosis occurs whenever base is not produced in sufficient amounts or is lost excessively. It also occurs if there are excessive H+ ions present or there’s decreased excretion of acids. Base, or HCO3-, is lost from diarrhea and renal disease. Increased H+ ion production occurs with ketoacidosis, lactic acidosis, and ingestion of toxins like methanol. Respiratory acidosis is caused by hypoventilation relative to CO2 production by respiratory and nonrespiratory abnormalities. Respiratory abnormalities include airway obstruction and extensive pulmonary edema. Nonrespiratory abnormalities include: drug overdose, neuromuscular disease, and head, spinal cord, and thoracic trauma. |
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Term
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Definition
The term for all the airways distal to the terminal bronchioles. An acinus is composed of respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli. It is considered the functional unit of the lung. |
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Term
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Definition
A contractile protein within muscle cells that interacts with myosin to cause muscle twitching and tension development. Actin is one of the proteins making up the sarcomeres of muscle tissue. During contraction, the actin filaments are pulled toward the center of the sarcomeres by myosin filaments, causing the sarcomeres and muscle to shorten, or contract. |
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Definition
| Pertaining to the sympathetic nerves of the autonomic nervous system that use epinephrine or similar molecules as neurotransmitters. Any chemical or drug that mimics the effect of these neurotransmitters. Also called sympathomimetic drug or catecholamine. |
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Term
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Definition
The resistance to blood flow out of the ventricle during systole. |
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Term
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Definition
| A drug or substance having a specific cellular affinity that produces a predictable response, such as cholinergic or adrenergic agonists that stimulate cholinergic or adrenergic receptor sites. |
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Term
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Definition
| An open, air-filled bronchial tube in the outer 2/3rds of the lung made visible on an x-ray by its lucent contrast with the radiopaque appearance of the surrounding alveolar infiltrates. An air bronchogram shows that the opacification seen on a chest x-ray is located in the lung parenchyma instead of the pleural space. Air bronchograms are the hallmarks of infiltrates filling alveoli. |
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Term
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Definition
| A hormone secreted by the adrenal cortex which increases sodium reabsorption by the kidneys, thereby indirectly regulating blood levels of potassium, chloride, and bicarbonate, as well as pH, blood volume, and blood pressure. |
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Term
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Definition
| A pH above normal (>7.45) caused by an actual or relative decrease of H+ amounts, or increase of HCO3-. Alkalosis is the general term for this condition in any part of the body. Alkalemia is the more exact term for ABG interpretation because it refers specifically to elevated pH in the blood (plasma), but in practice alkalosis is more commonly used for ABG’s. Alkalosis (alkalemia) can be caused by a metabolic or respiratory mechanism. Causes of metabolic losses of H+ include: hypokalemia, gastric suction and vomiting, Metabolic gains of HCO3- are caused by hypochloremia and excessive therapeutical administration of HCO3-. The cause of respiratory alkalosis is simply a primary increase of alveolar ventilation relative to CO2 production. This hyperventilation is the result of an increased stimulus to breath from such things as pain, anxiety, hypoxemia, and acidosis. |
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Definition
| The loss of hair from the head or body, sometimes to the extent of baldness. This type of hair loss is different from inherited male baldness, and affects both males and females. Current evidence suggests it’s an autoimmune disorder in which the body’s immune system attacks hair follicles and disrupts normal hair formation. |
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Term
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Definition
| A small glycoprotein formed in the liver and released to the blood serum that blocks several proteolytic enzymes that otherwise degrade and destroy tissue. Additional information--It was previously called a1-antitrypsin factor because it inhibits the proteolytic enzyme trypsin, but has been renamed because it also inhibits other proteases, which are a class of enzymes that degrade, or hydrolyze, the peptide bonds that join amino acids together in protein. It’s of special importance to pulmonary medicine because its normal level of 200-400 mg/dl is much lower in some persons with a certain genetic phenotype, thus predisposing them to less protection from proteolytic enzymes, which may lead to the destruction of lung tissue, causing panlobular emphysema. |
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Term
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Definition
| One of the four types of brain waves which occur when the person is relaxed, but no asleep or drowsy. The majority of brain waves are of this type. They are characterized by a relatively high voltage and a frequency of 8-13 cycles/sec. |
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Term
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Definition
| ALVEOLAR AIR EQUATION—The formula to derive the partial pressure of O2 in the alveoli. According to Dalton’s law, the higher the total pressure of an atmosphere, the higher the pressure of each constituent gas, and the lower the total pressure of an atmosphere, the lower the pressure of each constituent gas. Therefore, |
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Term
ALVEOLAR-ARTERIAL OXYGEN DIFFERENCE/A-a GRADIENT
[P(A-a)O2] |
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Definition
The pressure difference of O2 in the alveoli and
the arterial blood. The normal difference is 10-15 torr on room air, but if the lungs are diseased, O2 exchange between the alveoli and arterial capillaries may be significantly hindered, causing an elevated A-a gradient. Calculation of the A-a gradient requires a known FIO2, PAO2 and PaO2. This requires an ABG
to obtain the PaO2 and the PaCO2.The latter is then used in the alveolar air equation to find the PAO2. The PaO2 is then subtracted from the PAO2 to obtain the A-a gradient: P(A-a)O2 = PAO2 - PaO2. The A-a gradient increases with higher FIO2 and greater age. Breathing room air, the normal A-a gradient for
a patient can be estimated by multiplying 0.4 x age in years. An increased
P(A-a)O2 is strictly an indication of respiratory defects in
oxygenation. Most respiratory abnormalities producing hypoxemia have an elevated
P(A-a)O2, but there are two situations in which there may be
hypoxemia with a normal P(A-a)O2: high altitudes and primary
hypoventilation. |
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Term
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Definition
| The branches from each respiratory bronchiole. Their walls are composed entirely of alveoli, and each alveolar duct ends in a cluster of alveoli called an alveolar sac. |
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Term
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Definition
| A reduction in the mass of circulating red blood cells. Anemia is not a disease but a symptom of disease. It is classified by red blood cell size as microcytic (small), normocytic (normal), or macrocytic (large). It’s also classified according to the amount of hemoglobin the RBC’s contain as hypochromic (low), normochromic (normal), or hyperchromic (high). In addition, it’s classified according to its etiology. Anemia is caused by bleeding (e.g., GI tract, uterus), vitamin or mineral deficiencies (esp. vit. B12, folate or iron), decreases in RBC production (e.g., bone marrow suppression from kidney failure or myelodysplastic syndromes), increases in RBC destruction (e.g., sickle cell anemia), or increases in RBC sequestration by the spleen (e.g., portal hypertension). |
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Term
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Definition
An oppressive pain or pressure in the chest caused by inadequate blood flow and oxygenation to heart muscle. It’s usually caused by atherosclerosis of the coronary arteries. |
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Term
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Definition
| X-ray examination of the heart and blood vessels using an injected radiopaque contrast medium. |
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Term
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Definition
| A strong vasoconstrictor secreted in an inactive form by the liver and converted to an active form in the lungs. It’s important for long-term vasoconstriction and regulation of urine formation. |
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Term
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Definition
| An ion carrying a negative charge. It is negatively charged because it has more electrons than protons (since electrons are negatively charged and protons are positively charged). It is attracted to the positive electrical pole or anode. |
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Term
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Definition
| A drug or substance that acts in opposition to the action of another substance, such as cholinergic or adrenergic antagonists that block cholinergic or adrenergic receptor sites. |
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Term
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Definition
| In front or above the elbow or at the bend of the elbow. |
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Term
| ANTIDIURETIC HORMONE (ADH) |
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Definition
| Also known as vasopressin, it’s a hormone secreted by the posterior pituitary gland that stimulates water reabsorption along the distal tubules of the nephrons in the kidneys, thereby reducing urine production. |
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Term
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Definition
| Peripheral chemoreceptors in the arch of the aorta sensitive to hydrogen levels that help control ventilation. Exposure to higher levels of hydrogen ions causes them to send increased signals to the medulla to increase ventilation. Decreased exposure to hydrogen ions causes them to send decreased signals to the medulla for ventilation. They are far fewer in number than the carotid bodies peripheral chemoreceptors, and exert less influence over the respiratory centers. They send their impulses to the medulla via the vagus nerve. |
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Term
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Definition
| An antifungal antibiotic derived from a strain of Streptomyces nodosus and effective against a wide range of fungi. It is the drug of choice for treatment of disseminated histoplasmosis. It is also used to treat progressing coccidioidomycosis. It is administered IV, and when given systemically via IV, it is highly toxic and requires close monitoring to avoid renal and liver damage. |
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Term
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Definition
| A radiographic projection made by the x-ray machine at about a 45° angle from below the object in view. It’s sometimes required for a clearer view of the middle lobe of the right lung or the apical region. With this view shadows from the clavicles are projected above the thorax & away from the lungs, & the anterior & posterior portions of the ribs are lined up, reducing clutter in the view of the upper lungs. The lordotic position also has the effect of moving an anterior density upwards & a posterior density downwards from where they appear with a straight frontal view. |
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Term
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Definition
| A breathing pattern in which there is a prolonged inspiratory phase followed by a short expiratory phase, producing a reversed I:E ratio. It’s caused by injury to the pons or expiratory neurons of the medulla. The inspiratory neurons are not inhibited and breathing is dominated by an abnormal inspiratory stimulus. |
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Term
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Definition
| Any of a group of diseases causing thickening and loss of elasticity of arterial walls. There are 4 diseases, or types: atherosclerosis, arteriolsclerosis, arteriosclerosis obliterans, and calcific sclerosis of the medial layer of arteries (Monckeberg’s calcification). |
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Term
ARTERIOVENOUS OXYGEN CONTENT DIFFERENCE
[C(a – v)O2] |
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Definition
| The difference in O2 content in arterial and venous blood (normal is 3.5-5.0 vol %). The measurement requires simultaneous sampling of arterial and mixed venous blood. The arterial blood is obtained from an ABG and the mixed venous blood is obtained from a pulmonary artery catheter. The difference in O2 content gives an idea of the perfusion and oxygenation of the tissues. The equation for cardiac output shows the relationship: T = O2 ¸ C(a – v)O2 . In a patient with steady O2 consumption ( O2), the cardiac output ( T ) and the C(a – v)O2 are inversely proportional. As cardiac output increases, the arteriovenous O2 content difference decreases, and vice-versa. Unless the patient is agitated or has considerable temperature fluctuations, it’s usually assumed the O2 consumption is stable. An increased arteriovenous O2 content difference with stable O2 consumption means blood perfusion of the body’s organs is decreasing. Without adequate perfusion tissue hypoxia develops. When the C(a – v)O2 > 6.0 vol %, tissue oxygenation is inadequate. A reduced arteriovenous O2 content difference with stable O2 consumption means perfusion is above normal. A reduced arteriovenous O2 content difference with reduced O2 consumption and a normal cardiac output occurs when perfusion exceeds tissue demand, such as with hypothermia. A reduced arteriovenous O2 content difference that’s < 3.5 vol % indicates utilization of O2 is impaired for some reason. |
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Term
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Definition
| A pair of cartilages that form the posterior portion of the vocal cords. When they slide outward, they pull the vocal cords open, and when they slide inward, they pull the vocal cords shut. |
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Term
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Definition
| The accumulation of serous fluid in the peritoneal cavity. It most often occurs from impedance of venous return to the right atrium, such as with right heart failure. Cirrhosis of the liver, depletion of plasma proteins, and sodium retention are common contributing factors. If severe, it can restrict movement of the diaphragm and contribute to the onset of respiratory failure. |
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Term
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Definition
| A chronic inflammatory disease of the airways in which there are recurrent episodes of wheezing, dyspnea, bronchospasm, coughing, and air trapping. It’s also known as hyper-reactive airway disease. Asthmatic attacks are triggered by allergens, dust, fumes, medicines, dyes, odors, exercise, or infection. |
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Term
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Definition
| Abnormal breathing with irregular tidal volumes and respiratory rates. It’s seen in patients with respiratory muscle fatigue and impending respiratory failure. |
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Term
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Definition
| Coronary artery disease (CAD) in which there is blockage of arterial blood flow by deposits of plaques of cholesterol, lipids, and cell debris in the inner layers of the walls of arteries. It is the most common type of arteriosclerosis, and the greatest cause of disease and death in Western societies. |
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Term
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Definition
| The additional volume of blood pushed into the ventricles during diastole by the contraction of the atria. |
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Term
| ATRIAL NATRIURETIC PEPTIDE (ANP) |
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Definition
| A hormone secreted within the heart’s atrial tissue in response to increased blood pressure. It inhibits sodium reabsorption by the kidneys, thus increasing sodium and water excretion in the urine, which lowers blood volume and blood pressure. |
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Term
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Definition
| The outlets of the atria to the ventricles. The valve between the right atrium and right ventricle has three cusps and so it’s also the called the tricuspid valve. The valve between the left atrium and the left ventricle has two cusps, so it’s called the bicuspid valve. It also has the name mitral valve. |
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Term
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Definition
| A type of lymphocyte (a white blood cell class) that can become sensitized by antigens to produce and secrete antibodies into body fluid to neutralize the antigens. |
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Term
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Definition
| Any compound that combines with hydrogen ions, or can react with an acid to form a salt. Any substance that produces a negative ion and donates electrons to an acid to form covalent bonds. In water solution a base tastes bitter, turns red litmus paper blue, and produces free hydroxyl ions. |
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Term
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Definition
| In chemistry, a base is the nonacid part of a salt; a substance that dissociates to give hydroxide ions (OH-) in aqueous solutions. Base excess is the difference between the normal buffer base and the actual buffer base of a whole blood sample, not just the plasma. Another way of describing it is that it’s the number of millimoles of strong acid or base necessary to titrate a blood sample to a pH of 7.40, and a PaCO2 of 40 torr at a temperature of 37° C. The calculation of base excess is made from the measurements of pH, PaCO2, and hematocrit. The hematocrit is included because red blood cells have significant blood buffers. The total quantity of buffer anions in whole blood (the buffer base) is 45-50 mEq./L, about twice that of just the HCO3- in the plasma. Changes in plasma HCO3- from metabolic components change base excess, but acute changes in plasma HCO3- from respiratory components do not. Therefore, base excess gives a more complete analysis of the metabolic buffering capabilities of the blood sample, allowing analysis of just the metabolic components of acid-base balance. Base excess is measured in standard deviations of the standard bicarbonate, reported as positive or negative, depending on the direction in which the buffer base has deviated from normal. The larger the deviation, the more severe the change. A positive base excess means either base has been added or acid removed. A negative base excess means base has been removed or acid added. The normal range of base excess is ± 2 mE/L. |
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Term
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Definition
| The type of brain wave occurring when the person is awake and occupied or busy. They are the fastest of the brain waves. They are characterized by relatively low voltage and a frequency of more than 13 cycles/sec. |
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Term
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Definition
| Any salt containing the HCO3- (bicarbonate) anion. The measured HCO3- in the blood serum, or plasma, is an indicator of the alkali reserve. The concentration of bicarbonate is regulated by the renal system, but is also affected slightly by acute changes of PaCO2. Normal is 22-26 mEq/L. Standard bicarbonate is the plasma bicarbonate equilibrated with a gas mixture having a PaCO2 of 40 torr and a PaO2 > 100 torr at 37° C. Theoretically, this eliminates the respiratory influence on plasma HCO3- and allows evaluation of the pure metabolic component. Normal standard bicarbonate is also 22-26 mEq/L. |
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Term
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Definition
Breathing marked by several short breaths followed by long, irregular periods of apnea. It’s seen in patients with increased intracranial pressure and damage to the pons. |
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Term
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Definition
| A rare fungal infection, most common in North America, caused by inhalation of Blastomyces dermatitidis. It may produce inflammatory lesions of the skin or lungs, or a general invasion of skin, lungs, bones, central nervous system, kidneys, liver and spleen. It causes a fever, productive coughing, and muscle and joint aches. In progressive cases, abscesses develop in the lungs. The fungus inhabits areas of high organic matter, such as forest soil, rotting wood, and animal manure. |
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Term
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Definition
| The covering of glial cells around the brain’s capillaries that prevents chemicals from entering the brain tissue and causing dysfunction. |
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Term
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Definition
| The decreased affinity of hemoglobin for oxygen caused by elevated levels of carbon dioxide and hydrogen ions. |
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Term
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Definition
| A cup-shaped structure with a thin double membrane surrounding the glomerulus of each nephron of the kidney. It serves as a filter to remove organic wastes, excess inorganic salts, and water. Bowman’s capsule and the glomerulus are collectively referred to as the renal corpuscle. Blood is transported into the Bowman's capsule from the afferent arteriole (branching off of the interlobular artery). Within the capsule, the blood is filtered through the glomerulus and then passes out via the efferent arteriole. Meanwhile, the filtered water and aqueous wastes are passed out of the Bowman's capsule into the proximal convoluted tubule. elevated levels of carbon dioxide and hydrogen ions. |
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Term
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Definition
| A polypeptide secreted by various exocrine glands into blood plasma that’s a potent vasodilator. |
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Term
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Definition
| An abnormally low heart rate (<60 beats /min in adults, <70 beats/min in children). It’s less common than tachycardia, but may occur with hypothermia, as a side effect of certain medications, or with some cardiac arrhythmias. |
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Term
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Definition
| An abnormally slow rate of breathing (<12 breaths/min). It’s uncommon, but may occur in patients with head injuries, hypothermia, as a side effect of narcotics, and drug overdose. |
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Term
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Definition
| Harsh breath sounds with equal inspiratory and expiratory components. They are normal when heard over the bronchial tubes, but are abnormal when heard elsewhere, indicating an increase in lung tissue density, as in atelectasis or pneumonia. |
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Term
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Definition
| An abnormal condition of the bronchial tree characterized by irreversible dilatation and destruction of bronchial walls, usually in the lower portions of the lung, caused by damage from long-standing infection. The condition may be acquired or congenital, and may occur in one or both lungs. Acquired bronchiectasis is caused by airway obstruction, and infections such as bronchopneumonia, chronic bronchitis, tuberculosis, cystic fibrosis, or whooping cough. |
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Term
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Definition
| Abnormal voice sounds heard over lung consolidation with an increase in loudness, pitch, and clarity of vocal resonance. It is a type of pectoriloquy indicating solidification of lung tissue. |
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Term
| BRONCHOPROVOCATION TESTING |
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Definition
| A specialized pulmonary function test that uses substances such as methacholine or histamine to stimulate the airways into contracting and increasing airway resistance in order to detect occult asthma. |
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Term
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Definition
| A chemical substance that, when added to a solution, minimizes pH changes. There are several molecules that react with strong acids or bases to prevent large changes in the pH of body fluids. The principal buffers in the blood are carbonic acid, carbonates and bicarbonates, monobasic and dibasic phosphates, and proteins. Hemoglobin is an important protein buffer. The buffer base is the total blood buffers (anions) capable of binding H+. |
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Term
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Definition
| Discovered by the Swiss physicain, Wilhelm His Jr. (1863—1934). A group of modified muscle fibers arising in the AV node and continuing in the interventricular septum between the left and right ventricles as a single bundle until it divides into two trunks, the right & left bundle branches, that pass respectively to the right & left ventricles. Fine branches of the bundle branches spread out to all parts of the ventricles and are commonly called exclusively the Purkinje fibers, although, in reality, the entire system is the bundle of His. Normally, only the trunk is called the bundle of His, the two main branches being called the right and left bundle branches, and the smallest branches the Purkinje fibers. |
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Term
| CACHEXIA—(adj. form, cachectic) |
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Definition
| A profound state of constitutional, general ill health, malnutrition, and wasting. It occurs in many chronic diseases, malignancies, and infections. |
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Term
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Definition
| Small openings in the alveolar septa (walls) that connect an alveolus of one respiratory bronchiole to another respiratory bronchiole. |
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Term
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Definition
| The sum of two lung volumes. |
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Term
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Definition
| The continuous recording of a tracing of the concentration of CO2 of inhaled and exhaled air using a capnograph. It’s primary clinical use is to determine the adequacy of ventilation of patients during either general anesthesia or mechanical ventilation. Measurements of CO2 levels are also used to assess the physiologic status of patients with acute respiratory disorders. Interpretation of the capnogram can be useful in assessing trends in alveolar ventilation and detecting V/Q imbalance. It’s also used to ensure that endotracheal tubes are correctly placed in the trachea. |
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Term
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Definition
| The measurement of CO2, usually the end-tidal PCO2, in a volume of gas, most often by the methods of infrared absorption or mass spectrometry. It’s typically used for victims of cardiac or respiratory arrest, or a patient receiving mechanical ventilation, or under general anesthesia (where it’s standard practice). Capnometry has been used to estimate physiological dead space, to assess blood flow during cardiac arrest, and to determine PEEP levels. Capnometry is the measurement of CO2 in respiratory gases, while capnography is the graphic display of the measured CO2 levels as they change during breathing |
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Term
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Definition
| A chemical compound consisting of carbon dioxide combined with one or more free amino groups (NH2) of a protein molecule. |
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Term
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Definition
| One of the forms in which carbon dioxide exists in the blood in chemical combination with hemoglobin. One of the carbamino compounds. |
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Term
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Definition
| An enzyme found in the erythrocytes and tubule cells of the kidney that is a catalyst for the hydrolysis reaction of H2O and CO2 to form carbonic acid (H2CO3). |
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Term
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Definition
| Hemoglobin in which the sites usually bound to O2 are instead bound to carbon monoxide, which has an affinity for hemoglobin 210 times greater than oxygen. |
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Term
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Definition
| The cardiac output indexed to the size of the patient. |
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Term
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Definition
| The amount of blood pumped out of the left ventricle in 1 minute. |
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Term
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Definition
| Compression of the heart caused by excessive fluid or blood in the pericardium. It’s potentially a life-threatening condition in which elevated pressures within the pericardial sac interfere with blood filling the heart during diastole. Tamponade may result from injuries to the heart or great vessels, or from conditions that produce large pericardial effusions. |
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Term
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Definition
The last ring of cartilage of the trachea that forms the bifurcation for the two main stem bronchi. |
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Term
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Definition
| Peripheral chemoreceptors on or near the carotid sinus just distal to the bifurcation of the common carotid artery into the internal and external carotid arteries. They help control ventilation by responding to changes in blood levels of oxygen, carbon dioxide, and hydrogen (H+) ions. They are far more numerous than the aortic bodies and exert much more influence over the respiratory centers. The carotid bodies send their signals over the glossopharyngeal nerve to the medulla. |
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Term
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Definition
| The destructive phase of metabolism in which complex substances are broken down into simpler ones, with an accompanying release of energy. |
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Term
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Definition
| An ion with a positive electrical charge. It has more protons than electrons, which gives it the positive charge. It is attracted by the cathode (negative electrical pole). |
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Term
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Definition
| Very sensitive nerve cells located in cerebrospinal fluid inside the central nervous system on both sides of the medulla near its ventral surface that help control ventilation. They are only stimulated by H+ ions, but they’re also considered CO2 sensitive because the H+ around the chemoreceptors are only there because CO2 is also there and has released them. |
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Term
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Definition
| Sleep apnea for periods of 15-20 seconds caused by failure of the respiratory center of the brain. The apnea causes the PO2 to fall until hypoxemia stimulates the peripheral chemoreceptors to signal the medulla to cause inspiration. The process is repeated over and over, causing partial arousal and deprivation of restful sleep. |
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Term
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Definition
It’s also known as centriacinar emphysema, and is the most common of the two classes of emphysema, making up 90% or more of cases. It mainly involves destruction of respiratory bronchioles, the alveoli being less involved than in in panlobular emphysema. It’s caused primarily by smoking, with exposure to dust, chemical fumes, and air pollution also playing a role. It’s characterized by air trapping and hyperinflation from loss of lung elasticity, and growing hypoxemia. |
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Term
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Definition
| An abnormal breathing pattern in which there is a build-up in rate and depth of breathing to a peak, followed by progressive hypopnia and hypoventilation ending in a brief period of apnea before repeating the cycle over and over again. It indicates that the highest level of brainstem function is the middle of the mid-brain. With it, the oculocephalic reflex will be present but not normal, pupils will be small but reactive to light, and there will be decorticate posturing in response to painful stimuli. It also occurs when cardiac output is low, as with CHF, which delays the blood transit time between the lungs and brain. |
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Term
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Definition
| —An exchange of chloride ions in red blood cells in peripheral tissues or lungs in response to PCO2 in the blood in order to maintain electrostatic balance in the erythrocyte. It was first described by the Dutch physiologist Hamburger and is occasionally called the Hamburger phenomenon. |
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Term
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Definition
| Pertaining to nerve fibers of the autonomic nervous system that secrete acetylcholine at the myoneural junctions, or an agent or drug that produces the effect of acetylcholine. |
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Term
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Definition
| Tendonlike, fibrous cords that connect the heart valves to the papillary muscles and hold the cusps in place. |
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Term
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Definition
| A debilitating pulmonary disease with increased mucus production resulting in a productive cough for at least three months out of the year for more than two years in a row. It’s caused by inhaled irritants and/or repeated infections. Additional information—It is diagnosed by PFT if FEV1/FVC < 70% and a postbronchodilator FEV1 < 80%. It’s characterized by chronic inflammation and swelling of the airway, excessive mucus production, blocking of airways by mucus accumulation, bronchospasm, and air trapping. |
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Term
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Definition
| Threadlike projections of the epithelial cells lining the lumens of the conducting airways in the back of the nose, and from the larynx to the terminal bronchioles. They propel mucus and trapped contaminants upward to the pharynx, where they can be coughed out. |
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Term
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Definition
A pattern based on a 24-hour cycle, especially the repetition of physiologic phenomena, such as sleeping and eating. It’s also called the biological clock. |
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Term
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Definition
| The arterial anastomosis that encircles the optic chiasm (crossing of the optic nerves) and the pituitary gland on the ventral (bottom) side of the brain. It receives its blood from the two internal carotid arteries and the basilar artery formed by the two vertebral arteries, and is the source for the principal arteries supplying the brain. It’s named for Thomas Willis, British anatomist (1621-1675). |
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Term
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Definition
| Cells found in the epithelial mucosal lining of the terminal and respiratory bronchioles. They are nonciliated secretory cells bulging into the airway lumen, and are normally the only source of secretions in these airways where mucus cells are absent. |
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Term
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Definition
| The sensor used to measure PaO2 in blood gas machines and transcutaneous monitors and FIO2 in polargraphic oxygen analyzers. The electrode measures electrical current changes (amperometric) between a negatively charged platinum cathode and a positively charged silver-silver chloride anode caused by electrochemical reactions produced by exposure to O2. The resulting increase or decrease in current is proportional to the amount of O2 present and is displayed as PaO2 or FIO2. |
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Term
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Definition
| A type of buffer system in which all components of acid-base reactions remain in the system. Products accumulate and reach equilibrium with reactants, and no further chemical buffering activity can take place. The nonbicarbonate buffers of plasma proteins, hemoglobin, and phosphates are all closed buffer systems. |
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Term
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Definition
| The volume of gas remaining in the lungs after the small airways close during expiration. It’s measured by a specialized nitrogen washout technique. |
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Term
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Definition
| A substance which, when dispersed as much as possible in a solvent, remains uniformly distributed and does not form a true solution. For example, milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based liquid. |
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Term
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Definition
| An infectious disease caused by the fungus, Coccidioides immitis, which form spores in the soil in hot, dry regions. It’s also known as San Joaquin Valley Fever. 60% of infected people have no symptoms. Most of the remaining 40% have symptoms similar to those of a cold. In 0.5% of the cases the primary infection does not resolve and goes on to form cavities in the lungs and spread to the lymph nodes, meninges, spleen, liver, kidneys, etc. It can end in death, usually from meningitis. |
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Term
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Definition
| A measure of relative stiffness of the lung. It’s the volume change per unit change of pressure. |
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Term
| COMPUTED TOMOGRAPHY (CPT) |
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Definition
| A radiographic technique that selects a level in the body and blurs out structures above and below that plane, leaving a clear image of the selected area. The x-ray shadows are enhanced by use of a computer. |
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Term
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Definition
| A vertical plane that divides the body into anterior and posterior portions (belly and back). Also known as the frontal plane. |
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Term
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Definition
| A wide channel on the posterior side of the heart that collects venous blood from coronary circulation and returns it to the right atrium. |
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Term
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Definition
Any of several steroid hormones naturally secreted by the cortex of the adrenal gland or synthetically manufactured for a drug.
They influence or control body processes such as carbohydrate and protein metabolism, electrolye and water balance, and the function of the cardiovascular system and kidneys. Examples of drugs of this class include: Beclovent, Vanceril, Azmacort, AeroBid, Flovent, Pulmicort, and Advair (which also includes Serevent, a non-steroid). |
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Term
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Definition
| Pertaining to the ribs and diaphragm. The costophrenic angle is the angle formed by ribs and diaphragm. |
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Term
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Definition
| A form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, and other covalent bonds. Covalence is the number of electron pairs an atom can share with other atoms. |
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Term
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Definition
| The last cartilage of the larynx before the beginning of the trachea. It’s the only structure of the larynx that forms a complete ring of cartilage around the airway. |
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Term
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Definition
| Pertaining to the ulna (the largest bone of the forearm) or the forearm. |
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Term
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Definition
| Abnormal blue coloring of the skin and mucous membranes caused by increased amounts of deoxygenated hemoglobin. It is usually not observable unless at least 5 g/dL of hemoglobin are desaturated. |
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Term
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Definition
| Dead space is the portion of inhaled gas volume that does not participate in gas exchange. It may be anatomical, alveolar, or mechanical dead space. Anatomical dead space is the volume of the conducting airways; about 150 mL in the average adult. |
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Term
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Definition
| Abnormal posturing seen as rigid extension and rotation of the arms and legs, indicating dysfunction in the pons or midbrain portions of the brainstem. The legs rotate inward and the arms extend along the sides of the body with hands flexed outward, palms up, and fingers curled back. |
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Term
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Definition
| Characteristic posturing from lesions at or above the upper brainstem. The patient is rigidly still with the legs rotated inward and the arms folded over the chest with the hand flexed downward and the fingers curled up. |
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Term
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Definition
| The release of chemical mediators from storage in cells, especially cells in the blood, such as neutrophils, mast cells, basophils, macrophages, and platelets. |
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Term
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Definition
| The slowest of the four types of brain waves, which occur with deep sleep in a dreamless state from which an individual is not easily aroused. They have a relatively high voltage and a frequency of less than 3.5 cycles/sec. |
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Term
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Definition
| Loss of the difference in charge between the inside and outside of muscle cells’ plasma membranes due to a change of permeability and migration of sodium ions into the cell, causing a positive charge on the inside, which produces a contraction of the muscle. |
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Term
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Definition
| The rare location of the heart in the right hemithorax instead of the left because of either displacement by disease or a congenital defect. |
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Term
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Definition
| Sweating, especially profuse secretion from fever, physical exertion, exposure to heat, and stress. |
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Term
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Definition
The pressure in the arteries during relaxation of the
ventricles when they are filling with blood. Authorities differ somewhat, but the normal range is about 60-90 mm Hg. |
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Term
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Definition
| The volume of gas (in mL) that transfers from the lungs to the pulmonary capillaries per minute for each torr of difference of partial pressure between the alveoli and pulmonary capillary blood. CO is the gas normally used to measure DL, so diffusion capacity is usually designated DLCO, and is expressed in mL/min/mm Hg. DLCO is the difference between the volume of inhaled CO and the volume of exhaled CO, and is therefore a measurement of the ability of the lungs to transfer gases across the alveolar-capillary membrane. Normal DLCO for a 20 year-old is 40 mL/min/mm Hg. DLCO is reduced from alveolar destruction, small lung volumes, pulmonary fibrosis, pulmonary emboli, anemia. DLCO is increased from polycythemia, CHF caused by increased pulmonary blood volume, & increased cardiac output (such as from exercise). |
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Term
| 2,3-DIPHOSPHOGLYCERIC ACID (2,3-DPG) |
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Definition
| An organic phosphate manufactured by red blood cells that decreases the affinity of hemoglobin for oxygen by binding directly to deoxygenated hemoglobin. It’s an important adaptive mechanism for people in need of more tissue oxygen. It increases for anemia, vigorous exercise, living at high altitudes, and diseases causing hypoxemia. |
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Term
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Definition
| Two images of an object seen at the same time, doublevision. |
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Term
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Definition
| The apparent change of frequency of sound or light waves emitted by a source as it moves away from or toward an observer. The frequency increases as the source moves toward the observer and decreases as it moves away, such as the rising pitch of the whistle of an approaching train and the falling pitch of the whistle of a receding train. |
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Term
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Definition
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Term
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Definition
| Upper abdominal discomfort, often chronic or persistent, and colloquially referred to as “indigestion.” It may include such symptoms as fullness, bloating, belching, nausea, loss of appetite, or abdominal pain. It is sometimes related to food ingestion and sometimes to medicine side effects. |
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Term
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Definition
| Difficulty swallowing from various causes, such as: inflammation of the pharynx or esophagus, esophageal spasm, paralysis of the pharyngeal or esophageal muscles, inability to coordinate chewing and swallowing food, or a stricture of the pharynx or esophagus. |
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Term
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Definition
| A noninvasive method of visualizing cardiac structures using ultrasound. Ultrasound is inaudible sound at ultra high frequencies, which has different velocities that differ in density and elasticity from one kind of tissue to the next. This property permits the use of ultrasound to outline the shape of tissues and organs in the body. |
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Term
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Definition
| A heart beat originating outside the SA node. |
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Term
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Definition
| Increased resonance of voice sounds similar to bronchophony but not as clear and with a nasal or bleating nature, heard especially over lung tissue compressed or consolidated by pleural effusion. It’s a type of pectoriloquy. |
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Term
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Definition
| An electrical triangle formed by the patient’s right arm, left arm, and left leg, and used to position electrodes for an EKG. This positioning is used to determine the direction of cardiac vectors to various leads. |
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Term
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Definition
| The portion of the end-diastolic blood volume ejected during systole. Normal is about 60%-70%. |
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Term
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Definition
| Any substance containing free ions that make a substance electrically conductive. The substance can be the ions that are required by cells to regulate an electrical charge and flow of water molecules across cell membranes, such as sodium, potassium, or chloride. The substance can also be a chemical compound that ionizes when in a dissolved or molten state to produce an electrically conductive medium. |
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Term
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Definition
| Produced or originating from within a cell or organism. For example, intrinsic asthma is asthma assumed to due to some endogenous cause because no external cause (extrinsic asthma) can be found. |
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Term
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Definition
| Inspection of the body’s interior using an endoscope, a device consisting of a tube an optical system, such as a bronchoscope or colonoscope. |
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Term
| ENDOTHELIUM-DERIVED RELAXING FACTOR (EDRF) |
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Definition
| A factor produced in the endothelium of capillaries causing precapillary sphincter dilation. When normal function of the endothelium is disrupted by trauma, hypertension, or atherosclerosis, less EDRF is released and the inhibition of platelet aggregation is decreased. The damaged capillaries constrict, favoring the formation of blood clots and reducing blood flow. |
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Term
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Definition
| A hormone released by the kidneys when there is reduced oxygen content in the blood that stimulates production of erythrocytes in the bone marrow. |
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Term
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Definition
| A reddish-purple discoloration of the skin and mucous membranes with polycythemia. |
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Term
| EXPIRATORY RESERVE VOLUME |
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Definition
| The total amount of gas that can be exhaled from the lungs following a quiet exhalation. |
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Term
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Definition
Agents used to increase bronchial submucous gland secretion, which decreases mucus viscosity, facilitating the mobilization and expectoration of bronchial secretions. Examples include Guaifenesin (Robitussin), terpin hydrate, and potassium iodide (SSKI). |
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Term
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Definition
| A fibrous membrane covering, supporting and separating muscles, or the subcutaneous tissue that connects the skin to the muscles. |
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Term
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Definition
| The transmission of light through flexible glass or plastic fibers by reflections from the side walls of the fibers, which permits transmission of images around sharp bends. |
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Term
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Definition
| A method of determining cardiac output by calculating the difference in oxygen content of mixed venous and arterial blood. The difference is divided into the total oxygen consumption. Developed by the German physician Adolf Fick (1829-1901). |
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Term
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Definition
| A nonvolatile acid produced from other sources than CO2 and is not excreted by the lungs. They are produced from an incomplete metabolism of carbohydrates, fats, and protein. All acids produced in the body are fixed or nonvolatile acids except carbonic acid, which is the only volatile acid. Phosphoric acid, lactic acid, acetoacetic acid, and sulfuric acid are fixed acids. |
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Term
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Definition
| The opening in the fetal heart in the septum between the right and left atria that permits blood to flow from the right atrium to the left atrium and bypass the lungs. It normally closes at birth because of hemodynamic changes as the infant begins to breath. Sometimes it remains open and causes venous admixture to arterial blood and must be closed surgically. |
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Term
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Definition
| The maximum volume of gas that the subject can exhale as forcefully and as quickly as possible. |
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Term
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Definition
| A furrow or shallow depression. |
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Term
| FRANK-STARLING LAW OF THE HEART |
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Definition
| The force of muscular contraction is determined by the length of cardiac muscle. Within limits, the greater the length of the stretched fiber, the stronger the contraction. |
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Term
| FUNCTIONAL RESIDUAL CAPACITY |
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Definition
| The total amount of gas remaining in the lungs after a resting expiration. |
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Term
| GALVANIC FUEL CELL O2 ANALYZER |
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Definition
| An electrochemical analyzer that measures gas concentrations by measuring the change in current between the negative and positive electrodes of a fuel cell by the introduction of O2. |
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Term
| GASTROESOPHAGEAL REFLUX DISEASE (GERD)— |
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Definition
| A condition in which stomach acid flows back into the esophagus, causing discomfort (called “heartburn”) and, in some cases, damage to the esophageal lining. Additional information—It happens because the lower esophageal sphincter doesn’t close properly. It’s thought nearly half of all people experience heartburn at least once a month. As a disease, GERD occurs much more often. Some factors that may cause GERD are: alcohol abuse, obesity, and smoking. A variety of foods may also contribute to its occurrence, including citrus, chocolate, caffeine, fried food, spicy food, and tomato-based food. |
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Term
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Definition
| Supportive cells that surround the neurons in the central nervous system. |
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Term
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Definition
| The portion of hemoglobin that is comprised of four polypeptide (amino acid) chains. |
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Term
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Definition
| The main filter of the nephron located within the Bowman's capsule. The glomerulus resembles a twisted mass of tiny tubes through which the blood passes. The glomerulus is semipermeable, allowing water and soluble wastes to pass through and be excreted out of the Bowman's capsule as urine. The filtered blood passes out of the glomerulus into the efferent arteriole to be returned through the medullary plexus to the intralobular vein. |
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Term
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Definition
| The ninth cranial nerve, which innervates the tongue, larynx, and carotid bodies. |
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Term
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Definition
| The opening in the larynx between the two vocal cords. |
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Term
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Definition
| Mucus-producing cells found among the epithelial cells of the mucosal lining of the airways. |
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Term
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Definition
A bacterial species that causes acute respiratory infections and meningitis, especially in children under age 7. Infections may be mild (tonsillitis, otitis media), or severe and life-threatening (epiglottitis, septicemia, meningitis, postviral pneumonia, and endocarditis). |
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Term
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Definition
| The decreased affinity of hemoglobin for carbon dioxide and hydrogen ions caused by elevated levels of oxygen. |
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Term
| HEART BLOCK, FIRST DEGREE |
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Definition
| A condition in which the conduction of impulses through the AV node is delayed, but all atrial beats are still followed by ventricular beats. It’s recognized on the EKG by a prolonged P-R interval. |
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Term
| HEART BLOCK, SECOND DEGREE TYPE I |
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Definition
Also called Wenckebach or Mobitz Type I, it’s an arrhythmia caused by an abnormality in the AV junction that blocks some of the impulses through the AV node. It’s characterized by a variable PR interval which progressively increases until one impulse doesn’t pass through the AV node to the ventricles. The cycle then repeats itself with a progressively longer PR interval until another beat is dropped, which show up as a missing QRS complex. It’s frequently caused by increased parasympathetic tone; use of digitalis or propranolol; or a preceeding MI. It doesn’t cause symptoms and often treatment is not necessary, but it may sometimes impair cardiac output. |
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Term
| HEART BLOCK, SECOND DEGREE TYPE II |
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Definition
| Also called Mobitz Type II. A type of heart block in which some atrial complexes are not conducted to the ventricles. PR intervals have a constant length, but QRS complexes are dropped periodically, usually every second, third, or fourth beat. |
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Term
| HEART BLOCK , THIRD DEGREE |
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Definition
| A condition in which there is no conduction of atrial impulses to the ventricles and the atria and ventricles beat independently of one another. |
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Term
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Definition
| An indirect method for determining FRC. The technique uses a closed rebreathing circuit, & is based on the assumption that if a known volume & concentration of inert He is put in the closed circuit and rebreathed, eventually the concentration of He will equilibrate between the spirometer & the lungs. To measure the FRC, several parameters have to be determined: (1) the volume of He added to the closed spirometer; (2) the initial He %; (3) the final He %; (4) the spirometer temperature; (5) the time necessary for equilibration. The FRC is then calculated as follows: FRC = (vol He ¸ FiHe) x [(FiHe – FfHe) ¸ FfHe)]. |
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Term
| HENDERSON-HASSELBALCH EQUATION |
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Definition
The formula showing that the pH of a buffer is determined by the ratio of base (bicarbonate) to the concentration of weak acid (dissolved CO2). pH = pK + log [(HCO3-)¸ (PaCO2 x 0.03)]. The equation demonstrates that arterial pH is not determined by absolute values, but by the ratio of HCO3- to PaCO2, which for a normal pH, is 20 (HCO3-) to 1 (PaCO2). Abnormalities of one component can be compensated for by the other to return the ratio to 20:1. |
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Term
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Definition
| The solubility of a gas in a liquid solution at constant temperature is proportional to the partial pressure of the gas above the solution. |
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Term
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Definition
| Enlargement of the liver. |
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Term
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Definition
| Lung inflation and deflation reflexes that help regulate rhytmic ventilation of the lung. The receptor sites are located in smooth muscle in the bronchi & bronchioles and are activated by stretching or retraction of lung tissue. The inflation reflex inhibits inspiration & prev. further inflation. Sudden deflation of the lung stimulates inspiratory efforts and increases respiratory rate. The Hering-Breuer reflex is only activated at large VT’s (> 800 mL), and appears to not be a control mechanism for quiet breathing. It is important for regulating respiratory rate and tidal volumes during exercise. The reflex was first described by the German, Heinrich Hering, & Austrian, Josef Breuer, in 1868. |
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Term
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Definition
| A humoral substance found in many cells, such as mast cells, basophils, and platelets, that is released when the cells are injured. It produces vasodilation, increased permeability of blood vessel walls, and constriction of bronchioles. |
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Term
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Definition
| A systemic, fungal, respiratory disease caused by Histoplasma capsulatum. It is the most common fungal infection in the United States. The fungus is found in soil with high organic content and undisturbed bird droppings, and the infection is endemic in the Ohio River valley. It causes alveolar consolidation, destruction of alveoli and pulmonary capillaries, forms granulomas and cavities, and fibrosis and calcification of lung tissue. |
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Term
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Definition
| A portable device small enough to be worn by someone during normal activity, consisting of an EKG recording system capable of storing 24 hours of EKG activity. It’s useful for obtaining a record of cardiac arrhythmias that would not be detected by a conventional EKG of short duration. It was invented by Norman Jefferis Holter (1914—1983), American biophysicist. |
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Term
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Definition
| A substance originating in an organ or gland that is conveyed through the blood to another body part, chemically stimulating that part of the body to increase or decrease its activity or to increase or decrease secretion of another hormone. |
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Term
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Definition
| The pressure at a given depth of a non-moving (static) fluid as a result of the weight of the liquid above that point, plus any pressure acting on the surface of the liquid. |
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Term
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Definition
| An excess of CO2 (> 45 torr) in the blood. Hypercarbia is a synonym. It’s caused by a normal or increased metabolism without adequate ventilation. The best parameter for evaluating ventilation is the level of PaCO2, and hypercapnia, or elevated PaCO2, indicates inadequate ventilation. A reduction of E (minute ventilation) produces hypercapnia unless metabolism is also reduced. If the E is reduced and the PaCO2 elevated, ventilation effectiveness could be normal but the ventilation quantity insufficient. In that case, the cause of the hypoventilation and hypercapnia is not in the lungs, but usually is caused by either neuromuscular disease or depression of the ventilatory drive by medications. |
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Term
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Definition
| Having a greater concentration of solute than another solution, and consequently exerting more osmotic pressure than that solution, such as a hypertonic saline solution that contains more salt than body fluids. |
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Term
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Definition
| Increase in bulk without multiplication of parts, as in thickening of muscle fibers. |
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Term
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Definition
| An abnormal increase in the volume of circulating blood. |
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Term
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Definition
| Depressed rate and depth of breathing, such as occurs normally during deep sleep. It abnormally occurs in neuromuscular disease, such as Guillain-Barré and end-stage multiple sclerosis, and with greatly decreased lung compliance, such as with pulmonary fibrosis. |
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Term
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Definition
| A region of the brain which produces various hormones, including antidiuretic hormone and oxytocin. It regulates water balance, body temperature, and appetite. It is the chief region for the integration of sympathetic and parasympathetic activities. |
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Term
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Definition
| Deficient oxygenation of the blood as measured by PaO2 (< 80 torr). It usually occurs from / mismatch. Most commonly, the / mismatch is (1) from something that decreases ventilation to parts of the lung, such as bronchospasm or mucus obstruction of the airways. Blood flowing to such areas to not receive adequate O2 from the lungs. Another cause of hypoxemia is (2) diffusion defect, which is an abnormality of lung structure that slows O2 diffusion through the alveolar-capillary membrane. This type of hypoxemia usually responds well to increasing the FIO2 delivered to the patient. (3) Hypoventilation is an important cause of hypoxemia. Hypoventilation produces an elevated PaCO2, which reduces the PAO2, and its fall causes the PaO2 to do the same. (4) Lastly, hypoxemia may occur if the PIO2 that a person inhales is sufficiently low, such as at high altitudes or equipment failure when a patient is attached to a breathing circuit. |
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Term
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Definition
| A deficiency of PaO2 in body tissues below physiological needs. Hypoxia can be caused by the following things: (1) a decrease in total hemoglobin or an alterantion of hemoglobin types; (2) a left shift of the oxyhemoglobin dissociation curve; (3) inadequate blood flow; (4) histotoxic hypoxia in which tissue utilization of O2 is impaired by toxins, such as cyanide poisoning; (5) fetal hypoxia, caused by such things as: (a) poor function of the placenta, (b) preeclamptic toxicity, (c) prolapse of the umbilical cord, or (d) complications from anesthetic administration. |
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Term
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Definition
| Pertaining to jaundice, which causes yellowing of skin. Jaundice is a yellow discoloration of skin, the whites of the eyes, and other mucous membranes from |
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Term
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Definition
Pertaining to jaundice, which causes yellowing of skin. Jaundice is a yellow discoloration of skin, the whites of the eyes, and other mucous membranes from
increased levels of bilirubin in the blood. Bilirubin is the yellow breakdown product of the heme molecule of hemoglobin, and is normally excreted in bile and a tiny amount in urine, which gives urine its yellow color. Increased levels resulting in jaundice may be symptomatic of alcohol abuse, liver disease, gallstones, or pancreatic cancer. Neonates are also at increased risk of developing jaundice because they lack the intestinal bacteria that help break down bilirubin. Bilirubin breaks down with light, so icteric or jaundiced newborns are placed under a “bili light” to reduce bilirubin levels in the blood. |
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Term
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Definition
Antibodies manufactured by plasma cells derived from B lymphocytes in response to an antigen. There are five types of immunoglobulins: IgA, IgD, IgE, IgG, and IgM. |
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Term
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Definition
| Material that has passed into or through a substance or space. A shadow seen on a chest x-ray and assumed to be blood, pus, or other body fluids in the lung. |
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Term
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Definition
| An acute contagious viral respiratory infection caused by either influenza A or influenza B. It’s the most common viral respiratory infection, and is marked by fever, muscle aches, headache, weakness, cough, and sore throat. It usually strikes during winter in epidemics. It is frequently fatal in people with pre-existing illness or over age 65. Children and young adults are also at risk. It spreads through the air primarily but also by direct contact. |
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Term
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Definition
| An agent that increases or decreases the force of muscular contraction. Examples: digitalis is a positive inotropic drug that increases the force of myocardial contraction and quinidine is a negative inotropic drug that decreases myocardial contraction force. |
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Term
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Definition
| Referring to the spaces between tissues. |
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Term
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Definition
| An atom or group of atoms having a net electric charge. An ion is an atom or molecule where the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. |
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Term
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Definition
| Decreased blood supply to a body part. |
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Term
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Definition
| The most effective antituberculosis drug. It is usually given in combination with rifampin for 6-12 months to destroy all Mycobacterium tuberculosis bacilli in the patient’s body. Side effects may be hepatitis and peripheral neuropathy. The antidote for isoniazid overdose is pyridoxine. |
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Term
| ISOTHERMIC SATURATION BOUNDARY (ISB) |
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Definition
| The point in the tracheobronchial tree at which inspired air becomes 100% saturated with water vapor and 37° C, usually 2-3 airway subdivisions below the carina |
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Term
| J RECEPTORS (JUXTA-CAPILLARY RECEPTORS) |
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Definition
| The endings of C-fibers in the lung parenchyma near pulmonary capillaries. J-receptors are a type of congestion sensor stimulated by the inflammation of the alveoli from pneumonia, and the increased pulmonary capillary pressure of CHF and pulmonary edema. When stimulated, the J-receptors cause rapid, shallow breathing, strong laryngospasm, bradycardia, and mucus secretions. They probably contribute to the sensation of dyspnea that is felt with such conditions. |
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Term
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Definition
| A rhythm caused by ectopic impulses originating in/near the AV node that send the impulses down the normal conduction pathways in the ventricles. The P wave may be present or absent. If present, it may preceed, coincide with, or follow the QRS complex. Junctional rates may be from 40 to well over 100. With slow rates the junctional rhythm is an escape mechanism to continue ventricular funtion. This occurs when the SA node either fails to depolarize, impulses from the SA node fail to be conducted to the AV node, or the AV node fails to conduct impulses to the ventricles. If the AV node does not depolarize within 1-1 ½ seconds an ectopic focus will initiate an impulse called an escape beat, & a series of these escape beats becomes a junctional escape rhythm. Junctional rhythms are caused by AV node damage, electrolyte imbalance, digitalis toxicity, heart failure, heart valve disease, rheumatic fever, & myocarditis. |
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Term
| JUXTAGLOMERULAR APPARATUS |
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Definition
| A collection of cells located beside each renal glomerulus, consisting of a portion of the distal convoluted tubule arising from that glomerular capsule, segments of the afferent and efferent arterioles closest to the glomerulus, and the macula densa cells lying between these structures. In response to blood pressure changes, it initiates the renin-angiotensin mechanism to elevate blood pressure and increase sodium retention. |
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Term
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Definition
| A triad of diseases consisting of bronchiectasis, extrocardia, and paranasal sinusitis. It accounts for about 20% of all cases of bronchiectasis. It was discovered by Manes Kartagener (1897-1975), a Swiss physician. It’s an hereditary syndrome consisting of abnormal ciliary movement, malformation of the sinuses, and transposition of the viscera. |
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Term
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Definition
| Short, thin, faint linear shadows 1-3 cm long mostly seen along the lower lateral lung margins near the costophrenic angle, and always perpendicular to the nearest pleural surface. They are caused by thickening or infiltration of the interlobular septa, and also thickened portions of lymphatic vessels. They’re seen in interstitial lung disease, congestive heart failure, & metastasized cancer in the lymph vessels. They were discovered by P.J. Kerley, a British radiologist (b. 1900) along with Kerley A lines & Kerley B lines. Kerley A lines extend peripherally from the hilum, & Kerley C lines are fine interlacing lines in the middle of the lungs. Both Kerley A & B lines are caused the same way as Kerley B lines. |
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Term
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Definition
A gram-negative bacillus that normally inhabits the human gastrointestinal tract. It’s also known as Friedländer’s Bacillus,
and causes sinusitis, bronchitis or lobar pneumonia, particularly in men over age 40 and in alcoholics of both sexes. It is a common nosocomial disease and can be transmitted by airborne means or contact with freshly contaminated objects. Mortality is high because septicemia is a frequent complication. |
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Term
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Definition
Sounds heard during the taking of blood pressure using a sphygmomanometer and stethoscope. Named for Nikolai S. Korotkoff, Rlussian physician (1874-1920). |
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Term
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Definition
A deep and rapid breathing pattern that is normal during heavy exercise, but is abnormally seen in out-of-control diabetic acidosis. The metabolic acidosis stimulates the chemoreceptors to signal the medulla to hyperventilate in order to produce a respiratory alkalosis to balance the pH. |
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Term
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Definition
| A radiographic position in which the patient lies on one side or the other. It’s used to see if there is free fluid in the chest or to detect a pneumothorax. |
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Term
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Definition
| Inflammatory mediators that play a major role in causing asthma, being released during the antigen-antibody reaction. They are extremely powerful bronchoconstrictors and vasodilators, and cause bronchospasm, edema, leaking from blood vessels in the airway walls, and mucus production. |
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Term
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Definition
| Containing small spaces or cavities. |
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Term
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Definition
The portion of the nephron that leads from the proximal convoluted tubule to the distal convoluted tubule. The loop has a hairpin bend in the renal medulla. The main function of this structure is to reabsorb water and ions from the urine. |
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Term
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Definition
| A localized infection in the lung, most commonly resulting from a pneumonia caused by aspiration of anaerobic bacteria, or pulmonary infection by Klebsiella or Staphylococcus bacteria that leads to necrosis of lung tissue. Antibiotics are the primary treatment. |
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Term
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Definition
| Solid nodules of lymph tissue (primarily lymphocytes and macrophages) situated along the course of lymph vessels through which passes lymph fluid. They remove bacteria and toxins from the lymph fluid, and probably play a role in antibody production. They are the main source of the lymphocytes that enter the bloodstream of the systemic circuit. |
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Term
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Definition
Large lymph vessels that drain lymph fluid from the lymph nodes to the subclavian veins. |
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Term
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Definition
| A wandering type of phagocytic cell that is part of the nonspecific defenses of the body. It engulfs and destroys microorganisms, cell debris, and particles in the blood or tissues. |
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Term
| MAGNETIC RESONANCE IMAGING (MRI) |
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Definition
| An imaging technique in which high-frequency radio waves are beamed into the patient’s body while it’s subjected to a strong magnetic field. The nuclei of different atoms in the body absorb the radio waves at different frequencies under the influence of the magnetic field. Hydrogen nuclei (protons) respond to a radio frequency by reemitting radio waves of the same frequency. A computer analyzes the emissions from the hydrogen nuclei of water molecules in tissues and constructs images of structures based on the concentrations of the nuclei. |
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Definition
A secretory cell that can become sensitized to release various chemicals that stimulate inflammation. They are found throughout the body, but one of the areas of highest concentration is the respiratory tract. The chemicals they release cause allergic reactions like hay fever, hives, and asthma. |
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Term
| MAXIMUM VOLUNTARY VENTILATION |
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Definition
| The maximum volume of air a subject can breath in a 12-15 second period. It is a very patient-dependent test. |
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Term
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Definition
| The space or cavity separating the lungs. It contains the heart and its large vessels, trachea, esophagus, thymus, lymph nodes, and connective tissue. |
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Term
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Definition
| The lowest portion of the brainstem, connecting with the spinal cord inferiorly. It regulates heart rate, breathing, blood pressure, and reflexes like coughing, sneezing, swallowing, and vomiting. |
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Definition
| Commonly, the peritoneal fold that encircles the small intestine and connects it to the posterior abdominal wall. Other abdominal organs, however, also have a mesentery. |
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Term
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Definition
| The conversion of one type of tissue into a form that is not normal for that tissue. An example is myeloid metaplasia, which is the development of marrow tissue at sites at which it normally does not occur. |
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Term
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Definition
| Small vessels that carry blood directly from arterioles to venules or to the capillary beds. Capillary networks branch primarily from the metarterioles. In some abnormal conditions, such as septic shock, they carry blood directly from arterioles to venules, bypassing the alveoli and oxygenation. |
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Term
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Definition
| The spreading of disease from one organ or region to another. |
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Definition
| An abnormal hemoglobin variant in which oxygen oxidizes the iron present from the ferrous to ferric state, instead of combining with the hemoglobin for oxygenation. |
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Term
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Definition
| Tuberculosis that spreads throughout the body when a large number of bacilli escape into the bloodstream, producing numerous scattered small tubercles about the size of a pinhead. |
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Term
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Definition
The number of cases of disease in relation to a specific population. |
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Term
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Definition
| A class of agents that liquefy sputum or reduce its viscosity by mucolysis. Mucolysis is the chemical degradation or breaking down of mucopolysaccharide bonds that hold mucus together. Additional information--Examples are: acetylcysteine (Mucomyst), dornase alpha (Pulmozyme), and sodium bicarbonate (2% solution). Mucolytics play a role in the management of any respiratory disease that produces large amounts of mucus, such as bronchitis, cystic fibrosis, and bronchiectasis. |
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Term
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Definition
| Blockage of blood flow through a coronary artery supplying oxygen to heart muscle, which results in cardiac muscle cell death. |
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Definition
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Term
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Definition
| A contractile protein found in muscle cells that interacts with actin to contract muscles. It constitutes 45% of total muscle protein and consists of long chains of polypeptides joined to each other by side chains. |
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Term
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Definition
| A new and abnormal formation of tissues as a tumor or growth. It serves no useful function, but grows at the expense of healthy tissue. |
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Term
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Definition
The basic functional unit of the kidney. Its chief function is to regulate the concentration of water and soluble substances like sodium salts by filtering the blood, reabsorbing what is needed and excreting the rest as urine. A nephron eliminates wastes from the body, regulates blood volume and blood pressure, controls levels of electrolytes and metabolites, and regulates blood pH. Its functions are regulated by the endocrine system via hormones such as antidiuretic hormone, aldosterone, and parathyroid hormone. |
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Term
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Definition
| The condition of degeneration of the kidneys, especially the renal tubules, without inflammation occurring. |
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Term
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Definition
| Severe pain occurring along the course of a nerve. It is caused by pressure on nerve trunks, faulty nerve nutrition, toxins, or inflammation. |
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Term
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Definition
| A method to indirectly measure functional residual capacity (FRC). The method is based on several things: (1) the N2 concentration is 78% & is in equilibrium with the atmosphere; (2) the patient inhales 100% O2; & (3) the O2 replaces all the N2 in the lungs. The test begins & ends at end VT. The expired gas is collected & its volume & N2% measured. Since all the N2 that was once in the lung is exhaled and collected, the total volume of N2 does not changed. Therefore, FRC x 0.78 = VE (total expired vol.) x FEN2 (fractional expired N2 concentration). Rearranging the equation, it becomes FRC = VE x FEN2 ¸ 0.78. |
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Term
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Definition
Lung disease characterized by abnormally narrowed airways that reduce expiratory flow. |
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Term
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Definition
| The type of sleep apnea cause by obstruction of the airway. The obstruction occurs when the hypoglossal and pharyngoglossal muscles relax to the point of causing complete airway closure. The PO2 then falls until hypoxemia stimulates the peripheral chemoreceptors to signal the medulla to cause inspiration. This produces repeated stressful arousal and sleep deprivation. |
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Term
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Definition
| The normal oculocephalic reflex causes a person’s eyes to look around at surrounding objects when the head is moved from one side to the other. A test of brainstem function of this reflex is to rotate the head from side to side and observe eye movement. When the brainstem is not functioning down through the level of the pons, the reflex is absent. In this case, when the head is turned, the eyes remain fixed, looking straight ahead and appear immovable. |
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Term
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Definition
| Urinary output of less than 400 ml/day. It may result from poor perfusion of the kidneys from shock or dehydration; or from renal disease, such as tubular necrosis; or from obstruction to renal outflow, such as from bilateral hydronephrosis. If not reversed, oliguria ends in renal failure. |
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Term
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Definition
| The branch of medicine dealing with tumors, including study of their development, diagnosis, treatment, and prevention. |
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Term
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Definition
| The amount of force exerted by proteins in blood plasma to attract water molecules through a semipermeable membrane that is separating solutions of different concentrations of solute. It is measured by determining the hydrostatic (mechanical) pressure that must oppose the oncotic pressure to stop passage of the solvent through the membrane. Also known as colloid osmotic pressure, it is a form of osmotic pressure. |
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Term
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Definition
| A buffering system in which the reactants never reach equilibrium and consequently buffering activity can continue indefinitely. In the body, the only open buffer system is the bicarbonate system. In this system, H+ is buffered by HCO3- and produces H2CO3, which breaks down into H2O and CO2. As long as ventilation removes CO2 the system continues to operate. |
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Term
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Definition
| The force with which a solvent, usually water, passes through a semipermeable membrane separating solutions of different concentrations. It’s measured by determining the hydrostatic pressure necessary to prevent the entrance by osmosis of the solvent from the region of low solute concentration to the region of higher solute concentration. |
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Term
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Definition
| It consists of the increase of positive charges on an atom or the loss of negative charges when a substance combines chemically with oxygen with a net loss of electrons. Oxygenation is different in that there is no chemical change. Hemoglobin is oxygenated by O2 because oxygen is simply supplied to it, not chemically changed by it. |
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Term
| OXYGEN CONTENT (ARTERIAL) |
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Definition
| The total amount of oxygen present in the blood. This includes the O2 combined with hemoglobin and the amount dissolved in the plasma. The equation to determine arterial O2 content is as follows: CaO2 (in vol %) = 1.39 mL x Hb. x SaO2 + 0.003 mL x PaO2. It is a very important blood gas measurement because it does represent the total O2 contained in the blood (in this case arterial blood). If not taken into account, it can be mistakenly thought that an anemic person (who, by definition, has a low level of Hb.) with normal PaO2 and SaO2 is well oxygenated. In addition, a burn victim who has inhaled carbon monoxide, may have a normal PaO2 measurement from an ABG, and a normal Hb. level, as measured with a CO-oximeter, but the SaO2 (also measured with the CO-oximeter) could be very low if the CO poisoning is significant, producing a low CaO2. Normal CaO2 is 16-20 mL/dL of blood. |
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Term
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Definition
| Also termed panacinar emphysema, it’s the less common of the two types of emphysema. It has also been called “familial emphysema” because it’s caused by a genetic deficiency of sufficient a1-protease inhibitor, a substance which protects the lungs from the destructive action of the proteolytic enzymes, trypsin and elastase. Additional information--It’s estimated about 2-3% of all emphysema is of this type. It’s commonly found in the lower parts of the lungs and causes enlarged air spaces, or gaps, in lung tissue in the respiratory bronchioles, alveolar ducts, alveolar sacs and alveoli, significantly reducing the alveolar-capillary contact surface area. Hypoxemia occurs from this loss of gas exchange area and airflow obstruction from air trapping. |
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Term
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Definition
| The partial pressure of oxygen that results in the hemoglobin being 50% saturated with oxygen. Normal is 27 mm Hg. A low P50 means a high affinity of hemoglobin for oxygen, and a high P50 means a low affinity of hemoglobin for oxygen. P WAVE—The initial part of an EKG wave form that represents depolarization of the atria. |
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Term
| PAROXYSMAL ATRIAL TACHYCARDIA (PAT) |
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Definition
| A very rapid heart beat in the 160-240 range that suddenly occurs when an ectopic site in the right atrium takes over pacemaking from the SA node. The QRS complexes are normal, & each is preceeded by a P wave, which may be hidden behind the T wave because of the rapid rate. It’s caused by emotional stress; mitral valve disease; rheumatic heart disease; alcohol, caffeine or nicotine use; & digitalis toxicity. It terminates just as suddenly and spontaneously as it begins. It’s potentially dangerous because the rapid rate decreases filling time for the ventricles, which diminishes the heart’s ability to deliver O2 to the myocardium at the same time the fast heart rate is increasing myocardial demand for O2. |
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Term
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Definition
| The measurement of the hydrogen ion (H+) concentration of a solution. The pH scale has 14 degrees of acidity and alkalinity, with a pH of 7 assigned as absolute neutrality. Acids are defined as solutions capable of donating H+ and bases are defined as solutions capable of accepting H+. Increasing acidity is expressed as a number < 7, and increasing alkalinity as a number > 7. Maximum acidity is a pH of 0, and maximum alkalinity is a pH of 14. The pH scale is logarithmic, so there is a 10-fold difference between each unit. Arterial blood pH is the measurement of the H+ level in the plasma. The actual amount of H+ in arterial plasma is low (0.00004 mEq/L), an awkward number to work with, so the proposal was made to change the H+ term to pH by taking the negative logarithm (base 10) of the hydrogen ion, resulting in more manageable numbers. Since arterial blood is slightly alkalotic, the normal absolute mid-point between acidity and alkalinity is not 7.00 but 7.40, and the normal range is 7.35-7.45. |
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Term
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Definition
A wide terminal tubule in the renal pyramid, formed by the union of several straight collecting tubules and emptying into the renal pelvis. The principal straight excretory duct in the kidney medulla and papillae whose openings form the cribiform area. |
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Term
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Definition
| Small, cone-shaped extensions of myocardial muscle anchored in the walls and floors of the ventricles that provide tension to the chordate tendineae. |
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Term
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Definition
| The essential, functional elements of an organ, like the lung, as distinguished from its framework. The parenchyma of the lung is all the tissue that’s not part of the conducting airways. |
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Term
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Definition
| A microorganism capable of producing disease. |
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Term
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Definition
| A device that measures the maximum amount of gas that can be forcefully exhaled after a maximum inspiration, expressed in liters per minute. |
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Term
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Definition
| A general term for voice sounds of increased resonance heard through the chest wall. Whispered pectoriloquy is the transmission of the sound of whispered words through the chest wall heard upon auscultation, indicating an area of consolidation. |
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Term
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Definition
| An antibiotic and antiprotozoal effective in destroying Pneumocystis carinii, an opportunistic pathogen responsible for causing pneumonia in immunosuppressed individuals, notably those with HIV. The drug is toxic, and can cause hypocalcemia, leukopenia, and pancreatitis, among other things. |
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Term
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Definition
A saclike structure that envelops the heart. It’s comprised of tough, white fibrous pericardium and a thin serous pericardium. The fibrous portion is
made up of collagen fibers that give it some stiffness. The moist serous pericardium (or parietal pericardium) lines the inner surface of the sac. The two layers form the loose pericardial sac that extends down from the great blood vessels, over the heart, and onto the diaphragm. |
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Term
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Definition
| A process which uses light waves to detect tiny changes in blood volume. It measures the pulsations caused by the intermittent arterial blood flow through the tissues, identifying the arterial blood from other material (venous blood, tissue, bone) by the pulsation peaks. It is combined with spectrophotometry to measure the amount of light absorbed by the blood when there are pulsations (arterial) compared to when there are not (non-arterial) to compute a ratio of O2-saturated to non-O2-saturated arterial blood. Pulse oximeters use the principles of photoplethysmography and spectrophotometry to make estimates of SaO2 (SpO2). |
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Term
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Definition
| It is classified as a fungus based on aspects of its biochemistry, but its drug sensitivity is that of a protozoan. It is normally found in the lungs without doing harm, but is opportunistic and causes an often fatal pneumonia in immunosuppressed patients. It is primarily seen in persons with AIDS. |
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Term
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Definition
Inflammation of the lungs with consolidation due to infection with bacteria, viruses or other pathogenic organisms. Clinically, the term is used to indicate an infectious cause. Pneumonia types are categorized according to causative organism or location. |
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Term
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Definition
| A pulmonary inflammation similar to pneumonia except it’s caused by non-infectious causes, such as hypersensitivity pneumonitis caused by antigens in molds, bird feathers, resins; acute lupus pneumonitis, and malarial pneumonitis. |
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Term
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Definition
| —The process by which cells absorb nutrients and fluid. A portion of the cell membrane encircles the nutrient or extracellular fluid, enclosing it in a sac or vesicle. The sac is brought into the cell and its contents digested or absorbed. This process is used by capillaries to move large proteins through their walls. |
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Term
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Definition
| A protein found in many tissues and body fluids. It’s important for preventing fibrin clot formation. |
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Term
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Definition
| The linear radiographic appearance of obstructive atelectasis confined to a subsegmental portion of lung instead of an entire segment or lobe. It’s caused by restricted diaphragmatic movement, retained secretions producing small airway obstruction, & decreased surfactant production. It’s especially seen in patients having upper abdominal or thoracic surgery, chronic lung disease, pleurisy, rib fractures, or the obese. |
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Term
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Definition
| A shadow of uniform density that curves upward against the side of the chest on the front view, & upward against the back wall of the chest on the lateral view. It indicates a pleural effusion. |
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Term
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Definition
| A device that measures the flow of respiratory gases. The pressure gradient is directly related to flow, thus allowing a computer to derive a flow curve measured in liters per minute. |
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Term
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Definition
| A part of the upper pons that takes part in the automatic control of breathing and stimulates exhalation. |
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Term
| POLAROGRAPHIC O2 ANALYZER— |
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Definition
| An electrochemical analyzer that measures gas concentrations by measuring the change in current between the negative and positive electrodes of a fuel cell by the introduction of O2. It primarily differs from a galvanic fuel cell in that a battery is used as an external power source to increase the electrical potential and speed up response time. |
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Term
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Definition
| An excess of red blood cells. Primary polycythemia is caused by polycythemia vera, a myeloproliferative disorder caused by the uncontrolled reproduction of a single cell clone, resulting in increased RBC mass and hemoglobin that occurs independently of erythropoietin stimulation, the normal process for RBC formation. Secondary polycythemia results from some condition that stimulates erythropoiesis, most commonly chronic hypoxemia from COPD, obstructive sleep apnea, pulmonary fibrosis, or living at high altitudes. Relative polycythemia occurs because of a decrease in blood plasma, making the RBC’s relatively greater in proportion but not in numbers. This is known as spurious polycythemia, and is seen in persons dehydrated for various reasons. |
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Term
| POLYMERASE CHAIN REACTION (PCR)— |
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Definition
| A technique used for identification of organisms by beginning with a single molecule of genetic material and making unlimited numbers of copies of its genes. It is used to diagnose tuberculosis, diabetes, HIV, sickle cell anemia, etc. It provides identification much faster than older methods, the results being ready in 24 hours. |
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Term
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Definition
| The simultaneous recording of respiratory, cardiac, muscle, brain and ocular function during sleep. It is most often used to diagnose sleep apnea. |
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Term
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Definition
| Often simply called the pons, it’s a rounded protuberance on the ventral surface of the brain stem between the medulla and cerebral peduncles, and connects to the cerebellum by the mid-cerebellar peduncle. It also contains fibers that connect the medulla and cerebellum with the upper parts of the brain, and two respiratory centers that work in concert with those in the medulla. |
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Term
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Definition
Small openings in the alveolar septa that allow gas movement from one alveolus to another. |
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Term
| POSITRON EMISSION TOMOGRAPHY (PET)— |
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Definition
| An imaging technique using chemical compounds tagged with short-lived positron-emitting isotopes that are scanned by computerized cameras. It permits the determination of blood flow and volume, oxygen perfusion, and other physiological parameters. It’s especially useful for detecting cancer. |
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Term
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Definition
| The time interval between the beginning of the P wave and the beginning of the QRS complex. It represents the conduction time required for an impulse that’s initiated in the atria to travel through the AV node. |
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Term
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Definition
| Donut-shaped rings of smooth muscle that surround small arterioles and control the flow of blood into capillary beds. |
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Term
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Definition
| The area on the anterior surface of the chest over the heart and lower thorax. |
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Term
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Definition
| The volume of blood in the ventricle just before systole. |
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Term
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Definition
| Receptors that respond to stimuli originating within the body itself, especially ones that respond to pressure, position, or stretch. Proprioceptors are positional sensors in muscles, tendons, and joints, as well as pain receptors in muscles and skin that send stimuli to the medulla to increase ventilation. For that reason moving the limbs, slapping the skin, and other painful stimuli stimulate breathing in persons with a depressed respiratory drive. |
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Term
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Definition
| Fatty acids produced by the metabolism of arachidonic acid. They influence a broad range of biological processes, including vasodilation, vasoconstriction, vascular permeability, bronchoconstriction, and platelet aggregation. They are localized, short-range hormones that are formed rapidly, act in the immediate area, and then decay or are destroyed by enzymes. |
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Term
| PROXIMAL CONVOLUTED TUBULE |
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Definition
| The portion of the duct system of the nephron leading from Bowman’s capsule to the loop of Henle. The glomerular filtrate first passes into the proximal convoluted tubule where the reabsorption of water, glucose, amino acids, potassium, bicarbonate, sodium and chloride ions takes place. |
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Term
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Definition
| Itching, tingling, or faintly burning sensation of the skin that prompts a person to rub or scratch. It may be a symptom of a disease process, such as an allergic reaction or hyperbilirubinemia, or it may be due to emotion. |
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Term
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Definition
| An opportunistic, often water-born gram negative bacillus usually living in soil and decomposing organic matter. It may cause life-threatening infections, including nosocomial pneumonia, urinary tract infections, and sepsis. |
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Term
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Definition
| Drooping of the upper eyelid. It may be an early sign of disease involving the III cranial nerve (Oculomotor). It’s caused by congenital defects, cranial tumors, and neuromuscular diseases. In such a descending neuromuscular disease as myasthenia gravis, it could be an early warning sign of respiratory failure. |
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Term
| PULMONARY CAPILLARY WEDGE PRESSURE (PCWP) |
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Definition
| The pressure measured at the distal lumen at the tip of the pulmonary artery catheter when the balloon is inflated. It’s used as an estimate of left ventricular filling pressure. |
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Term
| PULMONARY CIRCULATORY SYSTEM |
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Definition
| The circuit of blood vessels that carries blood from the right ventricle to the lungs and from them to the left atrium. |
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Term
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Definition
| The portion of wave form of a heartbeat that represents depolarization of the ventricles. The first negative wave is the Q wave, the first positive wave is the R wave, & the second negative deflection is the S wave. The QRS interval is the duration of ventricular depolarization, or the QRS complex. A normal QRS interval is < 0.12 seconds (3 mm). Normal amplitude range of the QRS complex is 2-15 mm, depending on the lead and ventricle size. |
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Term
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Definition
| Rapid eye movement sleep. Sleep periods, lasting from a few minutes to half an hour, during which dreaming occurs. REM sleep alternates with non-REM sleep. |
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Term
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Definition
The initial blood filtering component of a nephron. It consists of two structures: a glomerulus and a Bowman’s capsule. |
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Term
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Definition
| The outer portion of the kidney between the renal capsule and the renal medulla. It forms a continuous smooth outer zone with a number of cortical columns that extend down between the pyramids. It contains the renal corpuscles and renal tubules, except for parts of the loop of Henle, which descend into the renal medulla. It also contains blood vessels and cortical collecting ducts. |
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Term
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Definition
| The innermost part of the kidney, divided up into a number sections known as the renal pyramids, which are chiefly composed of Henle’s loops and collection structures. |
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Term
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Definition
| The location where the medullary pyramids empty urine from the collecting tubules into the minor calyx. Histologically, it is marked by medullary collecting ducts converging to channel the fluid. |
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Term
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Definition
Restoration of the difference of charge between the inside and outside of muscle cells’ plasma membranes following depolarization, which causes a relaxation of the muscle . |
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Term
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Definition
| The volume of gas remaining in the lungs after a complete exhalation. |
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Term
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Definition
| Breathing which alternates between the use of the diaphragm for short periods and the use of the accessory muscles. It indicates end-stage respiratory muscle failure. |
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Term
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Definition
| The ratio of carbon dioxide produced by the body to oxygen consumed. |
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Term
| RESPIRATORY SYNCYTIAL VIRUS (RSV) |
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Definition
| A member of the paramyxovirus group of viruses, to which mumps, measles and parainfluenza also belong. It causes 25% of all respiratory illnesses in children under 1 year of age, occurring mostly in the winter and spring. It’s transmitted by aerosolized droplets and direct contact with infected individuals. It is rarely fatal. |
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Term
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Definition
| A broad category of disorders with differing etiologies, but all resulting in reduced lung volumes, particularly the inspiratory and vital capacities. The disorders are categorized according to origin, such as skeletal/thoracic, neuromuscular, pleural, interstitial, and alveolar. |
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Term
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Definition
| Resembling a net. The term “reticulum” means a network. |
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Term
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Definition
| Inward movement of the skin over the thorax during inspiration . It occurs with any lung disease in which the lung’s compliance is less than the chest wall’s. It’s seen when there are significant increases in the effort to breath from increased work of breathing, which causes large variations in pleural pressure. Retractions may be supraclavicular, intercostal, or subcostal. |
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Term
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Definition
| A genus of bacteria that are parasites and must be in living cells to reproduce. They are primarily transmitted by arthropods (lice, fleas, ticks, mites), but also cattle, sheep and goats. Several species are pathogenic. One causes Rocky Mountain spotted fever, and another typhus. |
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Term
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Definition
| A vertical plane through the longitudinal axis of the body, dividing it into right and left parts. It runs through midline structures such as the spine and navel. It’s also called the median plane. |
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Term
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Definition
| The three-cusped outflow valves (tricuspid valves) leaving the ventricles. The semilunar valve leaving the right ventricle is also called the pulmonic valve, and the semilunar valve leaving the left ventricle is also called the aortic valve. |
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Term
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Definition
The presence of pathogenic microorganisms or their toxins in the blood. |
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Term
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Definition
| A naturally occurring substance found in platelets and neurons of the brain; a powerful vasoconstrictor of systemic blood vessels. |
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Term
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Definition
| A condition in which blood perfusion of vital organs is inadquate to meet their metabolic requirements. The various forms of shock are hypovolemic, cardiogenic, septic, anapylactic, and neurogenic. |
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Term
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Definition
| A direct connection between venous and arterial circulation without mixed venous blood passing through the alveolar gas exchange areas of the lungs. These shunts can be normal or abnormal. There are two normal right-heart-to-left-heart anatomical shunts, the bronchopulmonary and thebesian vein connections. A right-to-left shunt causes poorly oxygenated venous blood to move directly in arterial circulation, dilution the oxygen content of arterial blood. Left-to-right shunts may also occur from the left side of the heart to the right side. In this kind of anatomical shunt, or bypass between the left (arterial) side of circulation to the right (venous) side, oxygen content of arterial blood is not affected, but cardiac workload is significantly increased. An example of an abnormal left-to-right shunt is a septal defect, or opening in the septum (wall) between the left and right sides of the heart. |
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Term
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Definition
| A radiographic finding that occurs when the edge of a well-established object such as the heart or aorta is obliterated because there is an infiltrate in physical contact, such as from pneumonia. |
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Term
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Definition
| A situation in which abnormally underventilated alveoli are perfused by normally oxygenated arterial blood. |
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Term
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Definition
| The posterior 1/4th of the roof of the mouth made of soft tissue and muscle that partly separates the oral cavity and the oropharynx and lifts during swallowing to block the nasopharynx. |
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Term
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Definition
| A substance dissolved in another substance. A typical example of a solution is sugar dissolved in water. Sugar is the solute and the water is the solvent. |
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Term
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Definition
| The measurement of coloring matter in a solution by the quantity of light that’s absorbed by the matter when the light passes through the solution, as indicated by comparison with the light portion of the electromagnetic spectrum. According to the Beer-Lambert law, each substance has a unique pattern of light absorption, and each substance’s pattern of light absorption changes in a predictable fashion according to the amount of the substance present. Spectrophotometry uses this law to identify substances (hemoglobin types) in blood samples and the amounts of each present. Oxygenated Hb. absorbs more red light and less infrared light than deoxygenated Hb., so comparison of a blood sample’s light absorption at the two light wavelengths gives the percentage of Hb. that’s saturated and the percentage that’s not saturated with O2. To measure additional forms of Hb, more light wavelengths are measured. The co-oximeter uses this process for accurate measurement of O2 saturation of each of several (usually 4) hemoglobin types. |
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Term
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Definition
| Needlelike in shape or appearance, usually pertaining to a body structure. |
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Term
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Definition
| Pertaining to the liver, spleen, intestines, and other abdominal organs. |
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Term
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Definition
| The portion of the cardiac cycle from the end of the QRS complex to the beginning of the T wave. It represents the time from the end of ventricular depolarization to the beginning of ventricular repolarization. |
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Term
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Definition
| The force of blood ejected by the heart is primarily determined by the length of the fibers of its muscular wall. An increase of diastolic filling lengthens the fibers and increases the force of myocardial contraction; a decrease of diastolic filling does the opposite. Discovered by British physiologist, Ernest H. Starling (1866-1927). |
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Term
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Definition
| Also called the angle of Louis, it’s the indentation of the sternum where the manubrium joins the gladiolus at the manubriosternal junction. The 2nd rib articulates with the top of the gladiolus at the sternal angle. It’s the reference point when measuring the jugular venous pressure (JVP) because its distance above the right atrium remains nearly constant in all positions (about 5 cm). |
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Term
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Definition
| The volume of blood ejected from the ventricle during systole. |
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| The force of blood ejected by the heart is primarily determined by the length of the fibers of its muscular wall. An increase of diastolic filling lengthens the fibers and increases the force of myocardial contraction; a decrease of diastolic filling does the opposite. Discovered by British physiologist, Ernest H. Starling (1866-1927). |
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| Also called the angle of Louis, it’s the indentation of the sternum where the manubrium joins the gladiolus at the manubriosternal junction. The 2nd rib articulates with the top of the gladiolus at the sternal angle. It’s the reference point when measuring the jugular venous pressure (JVP) because its distance above the right atrium remains nearly constant in all positions (about 5 cm). |
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| The volume of blood ejected from the ventricle during systole. |
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| A lipoprotein (proteins bound to fat) secreted by type II alveolar cells that decreases the surface tension of the fluid lining the alveoli, preventing alveolar collapse at low lung volumes. |
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| A catheter inserted into the pulmonary artery to determine intracardiac pressures and other hemodynamic parameters. Developed by U.S. physicians James Swan (b. 1922) and William Ganz (b. 1919). |
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| The medical term for inflammation of the synovial membrane, which lines joints possessing cavities known as synovial joints. The condition is usually painful, particularly when the joint is moved. Usually the joint swell due to synovial fluid collection. Synovitis may occur in association with arthritis, as well as lupus erythematosus, gout, and other conditions. |
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| SYSTEMIC CIRCULATORY SYSTEM |
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Definition
| The circuit of blood vessels that carries blood from the left ventricle of the heart to the tissues of the body and back to the right atrium. |
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| The peak blood pressure occurring in the arteries during ventricular contraction. The normal range is about 90-140 mm Hg, but authorities differ somewhat. |
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| A type of lymphocyte (a white blood cell class) that’s responsible for one type of immune response. T lymphocytes act as killer cells that carry antibodies for specific antigens, circulate throughout the body in the blood and lymph fluid, and destroy any antigens of that type they find. Some also become memory cells that can recognize the antigen in future exposures after very long periods and destroy it. |
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| The portion of an electrocardiogram tracing representing ventricular repolarization. |
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| Loss of drug responsiveness from continuous use of the drug. |
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| A rapid respiratory rate greater than 20 breaths/min. It’s normal with exercise or other conditions causing an increased metabolic rate, but is not normal at rest. In that case, some abnormal condition is stimulating the respiratory center to breath faster, such as hypoxia, acidosis, low blood pressure, brain injury, fever, pain or anxiety. |
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| The vibrations felt by palpation on the chest wall from vocal fremitus, which are vibrations created by sounds made by the vocal cords and transmitted down the tracheobronchial tree to the chest wall. Increased tactile fremitus is indicative of increased lung density, such as from pneumonia. Decreased tactile fremitus suggests the pleural space is filled with air (pneumothorax) or fluid (pleural effusion). |
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| The 19th or 20th generation of airway subdivisions from the trachea that form the end of the conducting airways. |
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| The area of the brain which receives all sensory stimuli except the olfactory. It’s also the center for appreciation of primitive, uncritical sensations of pain, crude touch, and temperature. |
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| A technique for determining cardiac output. A cold liquid such as sterile saline is injected into the bloodstream and the temperature change is measured downstream. |
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| One of the four types of brain waves that occur when the person is awake but relaxed and drowsy. They have a low voltage and a relatively low frequency of 4-7 cycles/sec. |
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| Any of the thick muscular tissue bands attached to the inner walls of the ventricles of the heart. |
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| A device that converts energy from one form to another, such as the transducer in an indwelling catheter that converts blood pressure to an electronic signal displaying digital numbers and a waveform on a monitor. |
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| A plane that divides the body into top and bottom portions. It’s also called the horizontal plane. |
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Used to describe cardiac arrhythmias, especially premature ventricular contractions. It means the abnormality occurs every third beat. |
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| A test that measures cell mediated hypersensitivity after exposure to tuberculoproteins and is used to determine the presence of a tuberculosis infection. A solution of PPD (purified protein derivative) of tuberculosis is injected under the skin and the size of the wheal produced after 48 and 72 hours determines if infection is present, but does not distinguish between active infection and that controlled by the person’s immune system or drugs. |
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| An infectious disease caused by the tubercle bacilus, Mycobacterium tuberculosis, and characterized by inflammation, caseation, necrosis, cavitation, fibrosis and calcification. It usually affects the lungs, but may spread to other parts of the body. It causes consolidation of alveoli, destruction of alveoli and pulmonary capillaries, caseous tubercles, cavities, fibrosis and cacification of lung tissue, and distortion and dilation of bronchi. |
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| Three scroll-shaped bones projecting from the side wall of the nasal cavity toward the nasal septum that create three irregular passages called the meatus. They are also known as the conchae. |
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| A portion of the EKG tracing that follows the T wave and preceeds the next P wave. It’s thought to represent remnants of ventricular repolarization or repolarization of the pa;illary muscles. It’s not always visible. |
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| One of two muscular tubes that propel urine from the kidneys to the bladder. In the adult, the ureters are about 10-12 inches long and 0.15 inches in diameter. |
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Definition
| A tube which connects the bladder to the outside of the body. |
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Definition
| Hives. Multiple swollen raised areas of the skin that are intensely itchy and last up to 24 hours. They may appear primarily on the chest, back, extremities, face, or scalp. |
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| UVULOPALATOPHARYNGOPLASTY |
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Definition
| Surgery of the oropharynx in which redundant soft palate, uvula, pillars, fauces, and sometimes posterior pharyngeal wall mucosa, are removed. The procedure may be done by using laser therapy. It is usually employed to correct intractable snoring or sleep apnea. |
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Definition
| A small depression in folds of mucous membrane between the epiglottis and tongue. When the tip of the Macintosh type blade of a laryingoscope is placed there during intubation it causes the epiglottis to rise off the larynx opening so that an endotracheal tube can be inserted into the trachea. |
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| A breathing technique that involves taking a deep breath and holding it while compressing the thorax by contracting the abdominal and intercostals muscles to significantly increase pressure in the lungs. This attempt to forcibly exhale while keeping the glottis, nose and mouth closed slows heart rate and increases pressure on the ear drums. It may be helpful in converting supraventricular tachycardia to a normal sinus rhythm of the heart, or in clearing ears that have become blocked during descent from a high altitude. It’s named for the Italian anatomist, Antonio Maria Valsalva (1666-1723). |
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| Inflammation of blood vessels. Vasculitis is primarily due to leukocyte migration and resultant damage. Both arteries and veins may be affected, but it can also occur separately. Inflammation of veins alone is called phlebitis and inflammation of arteries alone is termed arteritis. |
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| The amount of blood returned to the right side of the heart. |
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| The point during exercise where increased levels of lactic acid results in an increased CO2 production and minute ventilation to a level where CO2 production equals or exceeds O2 consumption. At this point metabolism becomes anaerobic, thereby decreasing energy production and increasing muscle fatigue. |
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| The front, anterior, or abdominal side. |
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| An acid that can be excreted in its gaseous form. Carbonic acid is the only significant volatile acid of human physiology. HCO3- (bicarbonate) and H+ (hydrogen) combine to form H2CO3 (carbonic acid), which breaks down into water (H2O) and CO2 (carbon dioxide), and they are exhaled. |
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| WHOLE BODY PLETHYSMOGRAPHY |
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Definition
| An indirect method for determining FRC by applying Boyle’s law (P x V = K) to volume and pressure changes between the patient’s lungs & the plethysmograph chamber in which the patient is situated. At the beginning of the test (end expiration) there’s an unknown volume of gas in the thorax (the FRC). The circuit the patient is breathing through is briefly occluded with a shutter while the patient is making an inspiratory effort. This inspiratory effort decompresses the chest & lowers the lung pressure to a new pressure level (P1). When the shutter is opened, a new body box pressure is created (P2). The body box volume (V2) is known, & the ratio of P2 to P1 is used with it to solve for one remaining unknown, V1 (the FRC): V1 = (P2 x V2) ¸ P1. |
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