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Cardiopulmonary Anatomy and Ph
Test Outline Questions BIO130 IU
276
Anatomy
Undergraduate 1
01/10/2008

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Term
Describe 3 functions of the larynx
Definition
1. Passageway of air between the pharynx and the trachea.
2. Protective mechanism against aspiration of solids and liquids
3. Generates sounds for speech
Term
Describe the functions of the epiglottis
Definition
prevents aspiration of food and liquids by covering the opening of larynx during swallowing
Term
What is the average length and diameter of the adult trachea?
Definition
11-13 cm long; 1.5 - 2.5 diameter
Term
where does the conducting zone end and the respiratory zone begin?
Definition
terminal bronchiole ends conducting zone and respiratory bronchioles begin respiratory zone
Term
List the structures that make up promary lobule for gas exchange
Definition
respiratory bronchioles, alveolar ducts, alveolar clusters that originate from single terminal bronchiole are primary lobule
Term
Define the function of alveolar macrophages
Definition
removes bacteria and other foreign particles; type III originated from stem cells, reproduce within the lungs
Term
Describe the function of Type II cells
Definition
granular pneumocyte 5% total alveolar surface primary source of pulmonary surfactant and decreases surface tension of fluid that lines alveoli
Term
Distinguish by name, the different neural tramsmitters that are reeleased by sympathetic and parasympathetic nervous systems
Definition
sympathetic - norepinephrine and epinephrine
parasympathetic - acetylcholine
Term
function of pleural fluid
Definition
parietal lines thorax
visceral attached to surface of lung
two pleura held together by serous fluid which allows them to slide across each other during inspiration and expiration
Term
Identify parts that make up sternum
Definition
top is manubrium sterni, middle is body and bottom is xiphoid process
Term
Identify nerves that innervate teh diaphragm
Definition
Terminal branches of phrenic nerves which leave spinal cord between 3rd and 5th cervical segments, supply primary motor innervation to each hemidiaphragm. Lower thoracic nerves contribute to motor innervatio nof each hemidiaphragm
Term
What is lung compliance and how is it expressed?
Definition
How readily the elastic force of the lungs accepts a volume of inspired air
expressed in liters per centimeter of water pressure (L/cm H2O)
Term
What is formula for lung compliance
Definition
CL = change in volume expressed in Liters divided by change of pressure expressed in cm H2O
Term
What is Hooke's Law?
Definition
when a truly elastic body, like a spring, is acted on by 1 unti of force, the elastic body will stretch 1 unit of length and when acted on by 2 units of force it will stretch 2 units of length and so force
Term
what is the formula that expresses Hooke's law w/ regard to elastance?
Definition
Elastance = change in pressure divided by change in volume
Term
What is the purpose of pulmonary surfactant?
Definition
significantly lowers alveolar surface tension
Term
Where is pulmonary surfactant produced?
Definition
alveolar type II cells
Term
What is pulmonary surfactant composed of?
Definition
phospholipids 90%
protein 10%
Term
What is the primary surface tension lowering chemical in pulmonary surfactant?
Definition
phospholipid dipalmitoyl phosphatidylcholine (DPPC)
Term
During exhalation, what happens to alveolus?
Definition
decreases in size
Term
When alveolus decreases in size during exhalation, what happens to the proportion of DPPC to alveolar surface area?
Definition
increases and this increases the effect of DPPC molecules and causes alveolar surface tension to decrease
Term
What happen sto the alveolus during inhalation?
Definition
alveolus increases
Term
When alveolus increases during inhalation, what happens to DPPC?
Definition
relative amount of DPPC to alveolar surface area decreases because the number of surfactant molecules does not change when size of alveolus changes which decreases the effect of DPPC molecules and causes alveolar surface tension to increase
Term
What is Laplace's Law?
Definition
distending pressure required to maintain size of bubble professively decreases as bubble size increases
Term
What happens in the absence of pulmonary surfactant?
Definition
alveolar surface tension increases to the level it would naturally have and distending pressure necessary to overcome recoil forces of liquid film coating the small alveoli is very high
Term
what is complete alveolar collapse
Definition
atelactasis
Term
What is the location of anatomical dead space and how is its volume assessed?
Definition
conducting airways; nose, mouth, pharynx, laryx, lower airways down to but not including respiratory bronchioles
1ML normal body weight 150 lb person volume anatomical dead space is 150 mL
Term
What are 5 general causes of pulmonary surfactant deficiency?
Definition
acidosis
hypoxia
hyperoxia
atelactasis
pulmonary vascular congestion
Term
What are 8 specific causes of pulmonary surfactant deficiency?
Definition
ARDS
IRDS
pulmonary edema
pulmonary embolism
pneumonia
excessive pulmonary levage or hydration
extracorporeal oxygenation
Term
Define alveolar dead space
Definition
alveolus is ventilated but not perfused with pulmonary blood thus air that enters alveolus is not effective in terms of gas exchange because there is no pulmonary capillary blood flow. amount of alveolar dead space is not predictible
Term
Cheyne Stokes
Definition
10-30 seconds of apnea followed by gradual increase in volume and frequency of breathing followed by gradual decrease in volume of freathing until another pariod of apnea occurs. associated with cerebral disorders.
depth of breathing increases, oxygen falls and carbon dioxide rises
Term
Kussmaul's Respiration:
Definition
increased depth (hyperpnea) and rate of breathing causes carbon dioxide to decline and oxygen to incrase
associated with diabetic acidosis (ketocidosis)
Term
What is the normal barometric pressure at sea level?
Definition
760 mmHg
Term
What is tidal volume?
Definition
The volume of air that normally moves into and out of the lungs in one quiet breath
Term
define ERV - expiratory reserve volume
Definition
maximum volume of air that can be exhaled after a normal tidal exhalation
Term
Tidal Volume
Definition
volume of air that normally moves into and out of the lungs in one quiet breath
Term
IRV
Definition
Inspiratory reserve volume
maximum volume of air that can be inhaled after a normal tidal volume exhalation
Term
ERV
Definition
Expiratory reserve volume
maximum volume of air that can be exhaled after normal tidal volume exhalation
Term
VC
Definition
Vital lung capacity - maximum volume of air that can be exhaled after maximal inspiration - IRV + Vt + ERV
Term
FRC
Definition
Functional Residual Capcity volume of air remaining in the lungs after a normal exhalation - ERV + RV
Term
Under normal circumstances, what should the patient's FEV1% be?
Definition
83% or greater
Term
What are the most commonly used pulmonary function measurements to determine the severity of patient's obstructive pulmonary disease and to distinguish between an obstructive and restrictive lung disorder
Definition
FEV, FEV1 and FEV1%
Term
What ratio is the comparison of the amount of air exhaled in one second to the total amount exhaled during an FVC maneuver
Definition
The FEV1/FVC
Term
In obstructive lung disorders, what happens to the FEV1 and the FEV1%
Definition
decreased
Term
In restrictive lung disorders, what happns to the FEV1, and the FEV1%
Definition
the FEV1 is down
but the FEV1% is normal or increased
Term
What is the majority of blood cells
Definition
erythrocytes - red blood cells
Term
What is is percentage of red blood cells in relation to the total blood volume
Definition
hematocrit
Term
What is normal hematocrit in males and females?
Definition
approx 45% in adult male and 42% in adult female
Term
What is the heart wall is composed of
Definition
epicardium, myocardium and endocardium
Term
What is the visceral layer of the pericardium, composed of single sheet of squamous epithelial cells overlying delicate connective tissue
Definition
epicardium
Term
What is thick contractile middle layer of uniquely constructed and arranged muscle cells
Definition
myocardium
Term
What is the bulk of the heart, layer that actually contracts
Definition
myocardium
Term
contractile tissue of the myocardium is composed of what?
Definition
fibers with the characteristic cross-striations of muscular tissue.
Term
What is the internal structure of myocardium?
Definition
cardiac muscle cells are interconnected to form a network spiral or circular bundles which effectively connect all the parts of the heart together. collectively teh spiral bundles form a dense network called fibrous skeleton of the heart which reinforces the internal portion of the myocardium. modified tissue fibers of the myocardium constitue the conduction system of the heart SA node, AV node, AV bundl of His and Purkinje fibers
Term
What is glistening white sheet of squamous epithelium that rests on a thin connective tissue layer. Located in the inner myocardial surface, it lines the heart's chambers.
Definition
endocardium
Term
What is contains small blood vessels and a few bundles of smooth muscles. it is continuous with the endothelium of the great blood vessels - superior and inferior vena cava
Definition
endocardium
Term
Right atrium receives venous blood from where?
Definition
inferior vena cava and superior vena cava
Term
Right atrium receives venous blood from inferior vena cava and superior vena cava and this blood is what in terms of O2 and CO2
Definition
low in oxygen and high in carbon dioxide
Term
Where does the tricuspid valve lie, held in place by and secured by?
Definition
between the right atrium and right ventricle and the leaflets are held in place by chordae tendinae, secured by papillary muscles
Term
What happens when ventricles contract?
Definition
tricuspid valve closes and blood leaves the right ventricle through the pulmonary trunk
Term
After blood passes through the lungs, it returns to the what by way of what?
Definition
the left atrium by way of pulmonary veins
Term
After blood passes through the lungs, it returns to the left atrium by way of pulmonary veins
This returning blood is high what and low in what?
Definition
high in oxygen and low in carbon dioxide
Term
Bicuspid/mitral valve lies where and does what?
Definition
between left atrium and left ventricle
and prevents blood from returning to left atrium during ventricular contraction
Term
left ventricle pumps blood through what?
Definition
ascending aorta
Term
The aortic valve lies where and does what?
Definition
at the base of the aorta that closes when teh ventricles relax and prevents backflow of blood into the left ventricle
Term
When ventricles contract (ventricular systole) what happens?
Definition
is forced into the pulmonary artery and the aorta and the pressure in these arteries rises sharply.
Term
What is is the systolic pressure
Definition
the maximum pressure generated during ventricular contraction
Term
What happens when the ventricles relax (ventricular diastole)
Definition
the arterial pressure drops
Term
what is normal pressure
Definition
normal pressure is about 120 mmHg and normal diastolic pressure is about 80 mmHg.
Term
what is stroke volume?
Definition
is the volume of blood ejected from the ventricle during each contraction
Term
What are Stroke volume ranges
Definition
Stroke volume ranges between 40mL and 80mL.
Term
What is Cardiac Output
Definition
Cardiac Output is the total volume of blood discharged from the ventricles per minute
Term
How is CO is calculated
Definition
by multiplying stroke volume by heart rate per minute (CO = SVxHR)
Term
What does CO directly influence
Definition
blood pressure - when stroke volume or heart rate increases, blood pressure increases and when stroke volume or heart rate decreases, blood pressure decreases
Term
what is normal adult blood volume?
Definition
Normal adult volume is 5L and 75 percent is systemic, 15 percent in the heart, 10 percent in pulmonary circulation -
Overall 60% in veins and 10 percent in arteries
Term
What is the double-walled sac the heart is enclosed in?
Definition
pericardium
Term
What is the primary function of the fibrous pericardium?
Definition
protect the heart, anchor the heart to surrounding structures, prevent the heart from overfilling
Term
What is the inner wall of the heart called?
Definition
serous pericardium
Term
The inner wall of the heart called the serous pericardium is composed of what two layers?
Definition
parietal and visceral pericardium
Term
What is the visceral layer of the pericardium called?
Definition
the epicardium
Term
What is the epicardium composed of?
Definition
single sheet of squamous epithelial cells overlying delicate connective tissue
Term
What does the myocardium consist of?
Definition
cross-striated tissue fibers that form a network of spiral bundles throughout the internal portion of the heart
Term
Where is the endocardium located?
Definition
inner myocardial surface and lines the heart chambers
Term
Blood supply that nourishes the heart originates directly from the aorta by means of which two arteries?
Definition
left coronary artery
right coronary artery
Term
The left coronary artery divides into which two branches?
Definition
circumflex branch and anterior interventricular branch
Term
The right coronary artery supplies the right atrium and then divides into which branches?
Definition
marginal branch and posterior interventricular branch
Term
Where does venous blood from the posterior position of the heart cleected by?
Definition
middle cardiac vein
Term
Where does venous blood from the anterior side of the heart empty into?
Definition
Term
The great and middle cardiac veins merge and empty into a large venous cavity within the posterior wall of the right atrium called what?q
Definition
coronary sinus
Term
A small amount of venous blood is collected by what vein which empties directly into both the right and left atrium?
Definition
thebesian vein
Term
Where does the right atrium receive venous blood?
Definition
inferior and superior vena cava
Term
A small amount of cardiac venous blood enters the right atrium by means of which vein?
Definition
thebesian vein
Term
which one-way valve lies between the right atrium and right ventricle
Definition
tricuspid valve
Term
What are the tricuspid leaflets held in place by?
Definition
chordae tendinae
Term
The chordae tendineae of the tricuspid leaflets are secured to the ventricular wall by what?
Definition
papillary muscles
Term
When the ventricles contract, the tricuspid valve closes and blood leaves the right ventricle thorugh what and enters the lungs by way of what?
Definition
pulmonary trunk
pulmonary arteries
Term
What valve separates the right ventricle from the pulmonary trunk?
Definition
pulmonary semilunar valve
Term
After blood passes through the lungs, it returns to the left atrium by way of what?
Definition
pulmonary veins
Term
What valve lies between the left atrium and left ventricle
Definition
bicuspid valve
Term
What does the left ventricle pump blood through?
Definition
ascending aorta
Term
What is the maximum pressure called that is generated during ventricular contraction?
Definition
systolic pressure
Term
When the ventricles relax, the lowest pressure that remains in teh arteries prior to the next ventricular contraction is called what?
Definition
diastolic pressure
Term
Compared to the pulmonary circulation, the minimum pressure in teh systemic system is how many times greater?
Definition
10 times greater
Term
What are the normal stroke volume ranges?
Definition
40 mL and 80 mL
Term
What is the total volume of blood discharged from teh ventricles per minute called?
Definition
cardiac output
Term
with regard to total blood volume of normal adults, how much is systemic circulation, in the heart and in pulmonary circulation?
Definition
75% systemic circulation
15% in the heart
10% in pulmonary circulation
Term
Overall, how much blood is in the veins and how much is in the arteries?
Definition
60% in the veins, 10% in the arteries
Term
Name the chemical components of blood
Definition
water, proteins (albumins, globulins, fibrinogen), electrolytes (cations like Na, K, Ca, Mg; anions like Cl, Po, So HCO), Food substances (amino acids, glucose/carbs, lipids, individual vitamins), Respiratory gases, individual hormones, waste products (urea, creatine, uric acid, bilirubin)
Term
Name the chemical components of blood
Definition
water, proteins (albumins, globulins, fibrinogen), electrolytes (cations like Na, K, Ca, Mg; anions like Cl, Po, So HCO), Food substances (amino acids, glucose/carbs, lipids, individual vitamins), Respiratory gases, individual hormones, waste products (urea, creatine, uric acid, bilirubin)
Term
What is another word for platelet?
Definition
thrombocytes
Term
Dissolved: When a gas like oxygen enters the plasma, what happens?
Definition
it maaintains its precise molecular structure and moves freely throughout the plasma in its normal gaseous state
Term
pH - normal arterial and venous ranges
Definition
a (arterial) 7.35 - 7.45
v (venous) 7.3 - 7.4
Term
Pco2 - normal arterial and venous ranges
Definition
a 35-45 mmHg
v 42-48 mmHg
Term
Clinically, which portion of the oxygen transport system is measured to assess the patient's partial pressure of oxygen?
Definition
dissolved 02
Term
what is Vol% defined as?
Definition
amount of O2 in milliliters that is in 100ml of blood
Term
how many million hemoglobin molecules is contained within each red blood cell?
Definition
280
Term
What is adult Hemoglobin designated as?
Definition
HbA
Term
In the normal adult hemoglobin, how many heme groups are there?
Definition
4
Term
When two oxygen molecules are bound to one Hb molecule, the Hb is said to be how much saturated?
Definition
50%
Term
What is hemoglobin bound to oxygen called?
Definition
oxyhemoglobin
Term
hemoglobin not bound with oxygen is called what? (two variations)
Definition
reduced hemoglobin or deoxyhemoglobin
Term
Is the amount of oxygen bound to hemoglobin directly or indirectly related to partial pressure of oxygen?
Definition
directly
Term
What does the globin portio of each hemoglobin molecule consist of?
Definition
four amino acid chains (polypeptide chains) that collectively constitute a globin
Term
how many alpha and gamma chains does fetal hemoglobin contain?
Definition
2 alpha chains and 2 gamma chains
Term
What is hemoglobin changed from teh ferrous state to ferric state known as?
Definition
methomoglobin
Term
What is the normal hemoglobin values for women, men and infants?
Definition
women: 12-15 g% Hb
men: 14-16 g%Hb
infants: 14-20 g% Hb
Term
At a normal arterial oxygen pressure, the hemoglobin saturation is only 97% because of what normal physiological shunts?
Definition
thebesian venous drainage to left atrium
bronchial venous drainage
alveoli that are underventilated relative to pulmonary blood flow
Term
What does the oxygen dissociation curve represent?
Definition
percent of hemoglobin that is chemically bound to oxygen at each oxygen pressure
Term
Why is the flat portion of the dissociation curve clinically significant?
Definition
hemoglobin has an excellent safety zone for the loading of oxygen in the lungs
diffusion of oxygen during the transit time hemoglobin is in the alveolar-capillary system is enhanced
increasing the P02 beyond 100 mmHg adds very little additional oxygen to the blood
Term
Why is the steep portion clinically significant?
Definition
P02 reductions below 60 mmHg indicate a rapid decrease in the amount of oxygen bound to hemoglobin
large amount of oxygen
Term
What does P50 represent?
Definition
partial pressure at which the hemoglobin is 50% saturated with oxygen
Term
What is the normal pressure in mmHg of P50?
Definition
27 mmHg
Term
What happens to the P50 when oxygen dissociation curve shifts to the right and why?
Definition
increases
affinity for oxygen decreases therefore pressure required to maintain same oxygen concentration increased
Term
When the oxygen dissociation curve shifts to the left, what happens to the p50?
Definition
decreases
Term
list factors that shift oxygen dissociation to the left
Definition
increased pH
decreased PCO2
decreased temperature
decreased DPG
HbF
CoHb
Term
List factors that shift the oxygen dissociation curve to the right
Definition
decreased pH
increased Pco2
increased temperature
increased DPG
Term
increased pH does what to the P50 and decreased pH does what to the p50?
Definition
increased pH shifts the oxygen dissociation curve to the left
decreased pH shifts oxygen dissociation curve to the right
Term
describe the oxygen dissociation curve shift with regard to both increased and decreased PCO2
Definition
decreased PCO2 shifts to the left, increased PCO2 shifts to the right
Term
describe effect on dissociation curve with regard to temperature
Definition
decreased temperature shifts to left
increased temperature shifts to the right
Term
describe DPG (2,3 diphosphoglycerate) (metabolic intermediary formed by RBCs during anaerobic glycolysis) with regard to effect on dissociation curve
Definition
decreased DPG shifts to the left
increased DPG shifts to the right
Term
What effect does HbF have on dissociation curve
Definition
shifts to left
Term
what effect does COHb have on dissociation curve?
Definition
shifts to the left
Term
Describe the Bohr effect:
Definition
The effect of Pco2 and pH on the oxyhemoglobin curve
most active in the capillaries of working muscles, particularly the myocardium
Term
What stimulates the bone marrow to increase RBC production and when does this occur?
Definition
When pulmonary disorders produce chronic hypoxemia, the hormone erythropoietin responds by stimulating RBC production
Term
What is RBC production known as?
Definition
erythropoiesis
Term
What is an increased level of RBC?
Definition
polycythemia
Term
What is an adaptive mechanism designed to increase the oxygen-carrying capacity of blood?
Definition
polycythemia
Term
What is the increased oxygen-carrying capcity in polycythemia offset by?
Definition
increased viscocity
when hematocrit reaches 55-60 percent, the increased viscocity requires a greater driving pressure to maintain a given flow.
Term
What happens because of increased viscocity associated with plycythemia?
Definition
work of the right an dleft ventricles must increase in order to generate the pressure needed to overcome the increased viscocity which can ultimately lead to left ventricular hypertophy and failure and to right ventricular hypertrophy, and cor pulmonale.
Term
What is hypoxic hypoxia?
Definition
PzO2 and CaO2 are abnormally low
Term
What are some conditions, besides pulmonary shunting, that can cause hypoxic hypoxia
Definition
low alveolar oxygen
diffusion impairment
ventilation perfusion (V/Q ratio) mismatch
Term
What are two conditions that can cause anemic hypoxia?
Definition
low amunt of hemoglobin in blood
deficiency in the ability for hemoglobin to carry oxygen
Term
Circulatory hypoxia
Definition
condition in which the arterial blood that reaches teh tissue cells may have a normal oxygen tension and content but the blood is not adequate to meet tissue needs
Term
What are two major forms of circulatory hypoxia?
Definition
stagnant hypoxia and arterial venous shunting
Term
What is histotoxic hypoxia
Definition
any condition that impairs the ability of tissue cells to utilize oxygen
Term
cyanosis
Definition
blue-gray or purplish discoloration seen on mucus membranes, fingertips and toes
Term
HCO3-
Definition
bicarbonate
Term
H2CO3
Definition
carbonic acid
Term
HCL
Definition
hydrochloric acid
Term
NaHCO3
Definition
sodium bicarbonate
Term
NaH2PO4
Definition
sodium acid phosphate
Term
NaHPO4
Definition
sodium alkaline phosphate
Term
List the ways carbon dioxide is transported in the blood
Definition
Plasma - carbamino compound, bicarbonate, dissolved CO2
Blood Cells - dissolved CO2, cabamino Hb, bicarbonate
Term
how the majority of Carbon Dioxide transported, what percent?
Definition
Most is bicarbonate - 63%
Term
what is the Haldane Effect
Definition
The fact that deoxygenated blood enhances the loading of carbon dioxide
Term
What are electrolytes?
Definition
Electrolytes are ions cabable of conducting a current in solution
Term
What is a buffer?
Definition
A buffer is a substance capable of neutralizing both acids and bases without causing an appreciable change in the original PH
Term
What is a strong acid?
Definition
A Strong Acid is an acid that dissociates completely into H+ and an anion
Term
What is a weak acid?
Definition
A Weak Acid is an acid that dissociates only partially into ions
Term
What is a strong base?
Definition
A strong base is a base that dissociates completely
Term
what is a weak base?
Definition
a weak base is a base that reacts with water to form OH- in equilibrium ; partial dissociation
Term
What is a dissociation constant?
Definition
a dissociation constant refers to weak acid or base systems that have an equilibrium between molecular form and its ion
Term
What is a pH of 7
Definition
neutral
Term
What is a pH less than 7?
Definition
acid
Term
What is a pH greater than 7?
Definition
base
Term
In chemistry, what is pH defined as
Definition
negative logarithm to the base of 10 of the hydrogen ion concentration
Term
What does an acid donate
Definition
hydrogen ions
Term
what does a base accept?
Definition
hydrogen ions
Term
What are the three mechanisms that maintain the narrow pH range
Definition
buffer system of the blood, respiratory ability to regulate elimination of CO2, renal ability to regulate excretion of hydrogen and reabsorption of bicarbonate ions.
Term
What is the most important buffer system in respiratory physiology
Definition
carbonic acid/sodium bicarbonate
Term
During acute ventilatory failure (hypoventilation), the blood PcO2:
Definition
increases
Term
During acute ventilatory failure (hypoventilation), the blood H2CO3:
Definition
increases
Term
During acute ventilatory failure (hypoventilation), the blood HCO3:
Definition
increases
Term
During acute ventilatory failure (hypoventilation), the blood HCO3- to H2CO3 ratio:
Definition
decreases
Term
During acute ventilatory failure (hypoventilation), the blood pH:
Definition
decreases
Term
In chronic ventilatory failure, the kidneys work to correct the pH status by:
Definition
retaining HCO3
Term
In chronic ventilatory failure, partial or comlete renal compensation can be verified when the HCO3- and pH readings on the Pco2/HCO3-/pH nomogram are
Definition
greater than expected for a particular Paco2
Term
During acute alveolar hyperventilation, what happens to the blood Pco2:
Definition
increases
Term
During acute alveolar hyperventilation, what happens to the blood H2CO3:
Definition
decreases
Term
During acute alveolar hyperventilation, what happens to the blood H2CO3:
Definition
decreases
Term
During acute alveolar hyperventilation, what happens to the blood HCO3:
Definition
decreases
Term
During acute alveolar hyperventilation, what happens to the blood HCO3 to H2co3 ratio:
Definition
increases
Term
During acute alveolar hyperventilation, what happens to the blood pH:
Definition
increases
Term
In chronic alveolar hyperventilation, the kidneys work to correct the pH status by:
Definition
excreting HCO3-
Term
In chronic alveolar hyperventilation, partial or complete renal compensation can be verified when the HCO3- and pH readings are:
Definition
less than exprected for a particular Paco2
Term
As a general rule, the kidneys do not overcompensate for abnormal pH - true or false?
Definition
true
Term
When matabolic acidosis is present, the HCO3- and pH readings are
Definition
less than expected for a particular paCo2
Term
Identify common causes for metabolic acidosis and alkalosis
Definition
three common causes of metabolic acidosis:
lactic acidosis (anaerobic metabolism due to unavailability of oxygen)
ketoacidosis (insulin i slow, serum glucose cannot easily enter tissue cells for metabolism therefore alternate metabolic processes that produce ketones is utilized)
renal failure (accumulation of hydrogen ions)
Term
what happens to the ventilatory response to a metabolic acidosis condition?
Definition
increases
Term
When metabolic alkalosis is present, the HCO3- and pH readings are:
Definition
greater than expected for a particular Paco2
Term
common causes of metabolic alkalosis
Definition
hypokalemia - depletion of body potassium that can occur from several days of intravenous therapy without adequate replacement of potassium, diuretic therapy and diarrhea -
hypochloremia - chloride ion concentration decreases, bicarbonate ions increase in an attempt to maintain normal cation balance in blood serum
gastric suction or vomiting - stomach acids depleted
excessive administration of corticosteroids - large dosses of sodium-retaining corticosteroids can cause the kidneys to accelerate the excretion of hydrogen ions and potassium
excessive administration of sodium bicarbonate
Term
What is Value for normal V/Q ratio
Definition
4:5 or .8
Term
What are pulmonary disorders that increase the V/Q ratio?
Definition
pulmonary emboli
partial or comlte obstruction in the pulmonary artery or some of the arterioles (atherosclerosis collagen disease)
extrinsic pressure on the pulonary vessels (pneumothorax, hydrothorax, presence of tumor)
destruction of the pulmonary vessel
decreased cardiac output
Term
In disorders that diminish pulmonary ventilation, the affected lung area receives little or no ventilation in relation to blood flow. What does this do to the V/Q ratio?
Definition
decreases
Term
When the V/Q ratio decreases, what happens to PAo2 and PCO2
Definition
PAO2 decreases and PACO2 increases
Term
What are Pulmonary disorders that decrease the V/Q ratio
Definition
obstructive lung disorders (emphysema, bronchitis, asthma)
restrictive lung disorders (pneumonia, silicosis, pulmonary fibrosis)
hypoventilation from any cause
Term
What molecule easily diffuses across the blood-brain barrier
Definition
blood brain barrier is very permeable to CO2 molecules
blood brain barrier is relatively impermeable to H+ and HCO3 ions
Term
What is the most powerful stimulus known to influence the medulla and what is responsible for monitoring hydrogen ions in the CSF?
Definition
Hydrogen ions in the CSF are the most powerful stimulus known to influence the respiratory components of the medulla. Central chemoreceptors are responsible for monitoring hydrogen ion concentration in the CSF.
Term
How do central chemoreceptors regulate ventilation?
Definition
Central chemoreceptors regulate ventilation through the indirect effects of CO2 on the pH of the CSF
Term
What are peripheral chemoreceptors sensitive to?
Definition
Peripheral chemoreceptors are special oxygen-sensitive cells that react to the reductions of oxygen levels in the arterial blood
Term
When are chemoreceptors activated?
Definition
chemoreceptors are not significantly activated until oxygen content of inspired air is low enough to reduced the PaO2 to 60 mm Hg (SaO2 about 90%)
Term
What are peripheral chemoreceptors specifically sensitive to and relatively insensitive to?
Definition
Peripheral chemoreceptors are specifically sensitive to the Po2 of the blood and relatively insensitive to oxygen content of the blood
Term
There are certain conditions where the Pao2 is normal (therefore peripheral chemoreceptors are not stimulated) yet oxygen content of the blood is dangerously low. What are they?
Definition
Such conditions include chronic anemia, carbon monoxide poisoning and methemoglobinemia
Term
Name the 2 types of peripheral chemreceptors and identify which one plays a greater role in responding to a low PaO2
Definition
carotid and aortic bodies
Carotid bodies play a much greater role in initiating an increased ventilatory rate in response to reduced arterial oxygen levels
Term
What are the four periods of lung development during fetal life?
Definition
embryonic, pseudoglandular, canalicular, terminal sac
Term
What day of embryonic life does a small bud of the lungs arise from teh esophagus?
Definition
24th day
Term
At what week gestation does the air-blood interface between the alveoli and the pulmonary capillaries and the quantity of pulmonary surfactant usually sufficient to support life?
Definition
28th week gestation
Term
What are the 15-20 segments of the placenta called?
Definition
cotyledons
Term
How is the deoxygenated blood carried from th efetus to the placenta?
Definition
two umblical arteries
Term
What is the normal Po2 in the umblical arteries and the normal PCO2?
Definition
02 20 mm Hg and Pco2 55 mmHg
Term
What are the reasons the maternal blood PCO2 is frequenly lower than expected during the final trimester of pregnancy?
Definition
alveolar hyperventilation due to growing infant restricting diaphragmatic excursion
Term
What are the three factors causing oxygen transfer from teh maternal to fetal blood in the intervillous space
Definition
maternal-fetal PO2 gradient
higher hemoglobin concentration in the fetal blood
greater affinity of fetal hemoglobin for oxygen
Term
how does oxygenated fetal blood flow out of the chorionic villi and return to the fetus?
Definition
by way of the umbilical vein
Term
What are three factors thought to cause wide variance between maternal and fetal Po2 and PCO2
Definition
placenta is actively metabolizing organ
permeability of placenta varies from region to region
fetal and maternal vascular shunts
Term
As oxygenated blood from the placenta returns to the fetus about half of the blood enters the liver and the rest enters inferior vena ava by flowing through what?
Definition
ductus venosus
Term
Once in the right atrium of the fetus, most of the blood flows directly into the left atrium through what?
Definition
foramen ovale
Term
Blood in the left atrium of the fetus enters where and is pumped where?
Definition
enters the left ventricle and is pumped to the heart and brain
Term
most of the fetal blood that passes into the pulmonary artery from the right ventricle bypasses the lungs by passing through what and flows directly into what?
Definition
passes through the ductus arteriosas and flows directly into the aorta
Term
How much of fetal circulation passes through the lungs and returns to the left atrium via what?
Definition
15%
pulmonary veins
Term
list structures in order in which fetal blodo passes through
Definition
ductus venosus, ductus arteriosus, common iliac arteries, external and internal iliacs, umblical arteries
Term
What special changes occur to fetal circulation after birty
Definition
placenta passed by mother
umblical arteries atrophy and become lateral umblical ligaments
umbilical vein becomes round ligament of liver (ligamentum teres)
ductus venosas becomes ligamentum arteriosum
flap on foramen ovale usually closes and becomes a depression in the interatrial septum called fossa ovales
ductus arteriosus atrophies and becomes ligamentum arteriosum
Term
describe what happens to fluid in fetal lungs upon birth
Definition
one third squeezed out of lungs as passes through birth canal
one third absorbed by pulmonary arteries
one third removed by lymphatic system
Term
how many million primitive alveoli are present at birth?
Definition
24
Term
Until what age does the number alveoli continue to increase
Definition
until age 12
Term
What are three stimuli that cause the infant to take the first breath
Definition
thermal, tactile, visual
Term
How much air enters the lungs during first breath of infant
Definition
40 ml
Term
What is the infant's intrapleural pressure decraes to before any air enters the lungs during the baby's first breath
Definition
-40 cm H2O
Term
What is average lung compliance of the newborn?
Definition
.005 l/cm H2o
Term
What is the average Raw of the newborn
Definition
30 cm H2O/L/sec
Term
two mechanisms that account for decreased pulmonary vascular resisteance when infant inhales the first tiem
Definition
sudden increase in alveolar Po2 which offsets hypoxic vasoconstriction
mechanical increase in lung volume which widens the caliber of the extra alveolar vessels
Term
describe mechanism that causes the foramen ovale to close at birth
Definition
pulmonary vascular resistence decreases a greater amount of blood flows through the lungs and therefore more blood returns to the left atrium this causes the pressure to increase in the left atrium and the flap of foramen ovale to close
Term
At birth, the newborn's Po2 must increase to what in order for teh ductus arteriosus to close
Definition
45-50 mm Hg
Term
PPHN is what?
Definition
(pulmonary hypertension of the neonate)
when ductus arteriosas remains open, permitting blood to pass through it, and pulmonary vascular resistence is elevated, persisten pulmonary hypertension of the neonate is said to exist
Term
PPHN stands for what and used to be called what?
Definition
persistent pulmonary hypertension of the neonate
used to be called persistenat fetal circulation
Term
3 substances released at birth said to have an effect on constriction of ductus arteriosus
Definition
bradykinin
serotonin
prostaglandin inhibitors
Term
What plays a role in activating the first breath at birth that is inactivated during fetal life?
Definition
peripheral and central chemoreceptors
Term
what does stimulation of the newborns trigeminal nerve cause the infants respiration and heart rate to do?
Definition
decrease
Term
stimulatio nof the preterm infant's irritant reflex is commonly followed by what?
Definition
respiratory slowing or apnea
Term
stimulation of the term infant's irrtant reflex causes what?
Definition
marked hyperventilation
Term
What is the head paradoxical reflex
Definition
deep inspiration elicited by lung inflation
Term
What are the two types of cardiac cells
Definition
contractile muscle fibers and "pacemaker cells" called autorhythmic cells
Term
What makes up the bulk of the musculature of the myocardium and are responsible for the pumping activity of the heart
Definition
Myocardial contractile fiber cells
Term
approximately one percent of the heart is composed of the what type of cardiac cells?
Definition
autorhythmic cells, the majority of which are located in the SA node
Term
autorhythmic cells, the majority of which are located in teh SA node. These cells initiate an action potential spontaneously which triggers the what to contract?
Definition
myocardial fibers
Term
The cardiac cells have four specific properties
Definition
automaticity, excitability, conductivity and contractility
Term
Define the term “ conductivity
Definition
conductivity is the ability of the heart cells to transmit electrical current from cell to cell throughout the entire conductive system
Term
Sympathetic neural fibers innervate
Definition
the atria and ventricles of the heart
Term
Sympathetic neural fibers innervate
Definition
the atria and ventricles of the heart
Term
When stimulated, the sympathetic fibers cause what to happen to the heart rate, AV conduction, cardiac contractility and excitability
Definition
the sympathetic fibers cause an increase in the heart rate, AV conduction, cardiac contractility and excitability
Term
Stimulation of the parasympathetic system causes what reaction in the heart rate, AV conduction, contractility and excitability
Definition
Stimulation of the parasympathetic system causes a decrease in the heart rate, AV conduction, contractility and excitability
Term
WHat is the ECG complex that represents ventricular depolarization?
Definition
QRS complex
Term
Three or more PVCs in a row represent what?
Definition
ventricular tachycardia
Term
How is the QRS complex with ventricular tachycardia?
Definition
wide an bizarre making it difficult to identify the P waves and T waves
Term
How is the rate of ventricular tachycardia?
Definition
Rate is regular or slightly irregular between 100-170 bpm
Term
What is Ventricular tachycardia is often initiated by ?
Definition
a pvc that is significantly premature, although it may occur suddenly after a normal sinus rhythm
Term
When ventricular tachycardia appears suddenly and then disappears moments later what is it called?
Definition
it is paroxysmal or intermittent ventricular tachycardia
Term
the ECG tracing shows only ventriculr tachycardia, what is it called?
Definition
sustained ventricular tachycardia or V-tach
Term
What is The blood pressure level during ventricular tachycardia
Definition
often decreased
Term
What are the characteristics of ventricular tachycardia?
Definition
P Wave usually cannot be identified
PR interval cannot be measured
QRS duration is usually greater than .12 second and bizarre in appearance. T wave cannot be identified
QRS rhythm is regular or slightly irregular
Term
Cite the functional unit of the kidneys
Definition
Nephrons are the functional unit of the kidneys
Term
What is hydrostatic pressure in the glomerulus capillary?
Definition
hydrostatic pressure in the glomerular capillary is about 55 mm Hg
Term
What is the hydrostatic pressure in bowman's capsule?
Definition
The hydrostatic pressure in Bowman's capsule is about 15 mm Hg
Term
How much fluid does the glomeruli filter per minute?
Definition
The glomeruli filter about 125 mL of fluid per minute
Term
The glomeruli filter about 125 mL of fluid per minute and of this, how much is excreted as urine?
Definition
Of this 125 mL, however, only about 1 mL is excreted as urine
Term
What is the average urine output per day?
Definition
The average urine output is about 60 mL/hour, or 1440 mL/day
Term
Identify the major “ion” found in the extra-cellular fluid
Definition
Sodium ions account for over 90 percent of the positively charged ions in teh extracellular fluid.
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