Term
| Pulmonary System Components of Physiology |
|
Definition
1. ventilation
2. gas exchange or respiration
3. transport of gases to peripheral tissue |
|
|
Term
|
Definition
| ventilatory rate x tidal volume |
|
|
Term
|
Definition
| RV + ERV + TV + IRV (5800 ml) |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Functional Residual Capacity |
|
Definition
|
|
Term
|
Definition
1200 ml
with obstructive diseases this value is higher because they cannot get the air out |
|
|
Term
| Expiratory Reserve Volume |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Inspiratory Reserve Volume |
|
Definition
|
|
Term
|
Definition
Neurons in Medulla and pons
Medulla has inspiratory and expiratory neurons
Pons has pneumotaxic and apneustic centers |
|
|
Term
| Afferent Connections to the Brainstem with respect to breathing |
|
Definition
-Hypothalamic and limbic: sensations of pain or alterations in emotion
-chemoreceptors: sense alterations in blood pH, CO2 and O2
- lung receptors: irritatnt, stretch, J receptor (juxtapulmonary
- joint and muscle receptors (an initial sharp increase in ventilation rate with exercise occurs due to sensation from receptors whereas the secondary gradual increase comes from changes in pH due to lactic acid production) |
|
|
Term
| Mechanics of breathing is affected by: |
|
Definition
compliance- tendency to recoil while inflated
elasticity- tendency to return to initial size
surface tension- surface active agent is surfactant
resistance to air flow- affected by pressure differences, diameter and length of airway |
|
|
Term
| Intrapulmonary and Atmospheric Pressures |
|
Definition
- inspiration is always active
- boyle's law: pressure of a given quantity of gas is inversely proportional to its volume
- inspiration: negative intrapulmonary pressure
- expiration: intrapulmonary pressure exceeds atmospheric pressure (760 mmHg) |
|
|
Term
|
Definition
the two opposing forces:
1. inward pull from the elastic recoil of the lung trying to collapse it
2. outward pull of the thoracic wall trying to expand the lung |
|
|
Term
|
Definition
| difference between intrapulmonary and intrapleural pressures and maintains lung near chest wall |
|
|
Term
| Partial Pressures of Gas in the atmospheric air |
|
Definition
79.94% nitrogen
21% oxygen
.03% CO2 |
|
|
Term
|
Definition
| differences in partial pressure of each gas within alveoli and pulmonary capillary create a pressure gradient moving from high to low |
|
|
Term
|
Definition
|
|
Term
| Ventilation and Perfusion Matching |
|
Definition
optimal respiration or gas exchange occurs if distribution of gas (ventilation) and blood (perfusion) match at level of alveolar capillary interface
(affected by body positions) |
|
|
Term
|
Definition
O2 is 98% transported by hemoglobin, 2% dissolved in blood
CO2 is dissolved in plasma, bound to a protein component of hemoglobin, or bicarbonate ions |
|
|
Term
| Oxyhemoglobin Dissociation Curve |
|
Definition
% saturation of hemoglobin and partial pressure of O2 with which the Hb is in equilibrium
- a shift to the right gives up O2 easier |
|
|
Term
| Cardiovascular System Function |
|
Definition
| transportation and distribution of essential substances to tissues of body and removal of by-products from cellular metabolism |
|
|
Term
|
Definition
|
|
Term
| Neural Control of heart vessels |
|
Definition
sympathetic (beta) = vasodilation
parasympathetic = vasoconstric |
|
|
Term
|
Definition
| blood returning to the heart or end diastolic volume (Frank Starling) |
|
|
Term
|
Definition
| influenced by intrinsic (myocaridal stretch) and extrinsic (sympathoadreal system) |
|
|
Term
|
Definition
| blood ejected out of heart is influenced by pressure generated in ventricle compared to pressure in systemic vasculature |
|
|
Term
|
Definition
-best indicator of cardiac function
- ratio of volume of blood ejected out of ventricles relative to volume of blood received by ventricles
-normal 60-80% |
|
|
Term
|
Definition
| affected by: total blood volume and pressure within venous vasculature |
|
|
Term
|
Definition
squeezed out during systole byt perfuse myocardium during diastole
- regulated by autonomic nervous system |
|
|
Term
| Exercise and vasculature response in gut |
|
Definition
| - norepi constricts blood vessels to digestive organs |
|
|
Term
| Myocaridum Metabolic Rate |
|
Definition
Rate Pressure Product = HR X systolic BP
aka double product
indication of myocardial O2 demands |
|
|
Term
| Conditions that can change ABG levels |
|
Definition
- diabetes
- drug or alcohol overdose
- kidney failure
- lung disease, chronic lung disease, blood clot in lungs, pneumonia
- severe dehydration
- severe infection (sepsis) |
|
|
Term
|
Definition
Anything that prevents the body from getting rid of CO2 => increases acid and decreases pH
- alveolar hypoventilation, hypercapnia |
|
|
Term
|
Definition
Anything which makes the body lose CO2 => decreases acid and increases pH
-- alveolar hyperventilation, hypocapnia |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Conditions leading to Respiratory Acidosis |
|
Definition
- central respiratory depression or other CNS problems: drug depression, CNS trauma, infarct, hypoventilation of obesity
- guillain barre, myesthenia gravis
- flail chest, contusion, restrictive lung disease, ARDS |
|
|
Term
| Causes of Respiratory Alkalosis |
|
Definition
ALWAYS due to increased alveolar ventilation
- head injury, stroke, anxiety-hyperventilation
- pulmonary embolism
- pneumonia |
|
|
Term
| Causes of Metabolic Alkalosis |
|
Definition
- loss of gastric acid via vomitting
- diuretic use: furosemide and thiazides |
|
|
Term
| Causes of Metabolic Acidosis |
|
Definition
- ketoacidosis, lactic acidosis, renal failure
- hyperventilation (Kussmaul respirations) |
|
|
Term
| Effects of Metabolic Acidosis |
|
Definition
| cardiovascular effects, depression of myocardial contractility, sympathetic overactivity, resistance to catecholamines, peripheral vasodilation, vneoconstriction, vasoconstriction of pulmonary arteries, hyperkalaemic effects on heart |
|
|
Term
|
Definition
pH: 7.35-7.45
PaO2: 80-100mg
PaCO2: 35-45 mg
HCO3: 22-26 mEq/L
SaO2 97-100% |
|
|
Term
alveolar hyperventilation
vs
alveolar hypoventilation |
|
Definition
hyper: PaCO2 increased
hypo: PaCO2 decreased
- >50 is respiratory failure |
|
|
