Basic Pulmonary Physiology Flashcards
Respiratory units
Areas of gas exchange (from proximal to distal): Respiratory bronchiole, alveolar ducts, alveoli
Four basic lung volumes
Inspiratory reserve volume (IRV), Tidal volume (TV), Expiratory reserve volume (ERV), residual volume (RV)
Tidal volume
Amount of air inhaled/exhaled with each normal breath (~0.5L)
Residual volume
Amount of air remaining in the lungs after full exhalation, maintains oxygenation between breaths
Vital capacity
Maximum amount of air that can be inspired/exhaled; IRV + TV + ERV
Anatomic dead space volume
Area with no gas exchange from nose to terminal bronchiole (150mL)
Physiologic dead space volume
Anatomic dead space volume + Alveoli dead space volume
Alveolar ventilation per minute
Respiratory rate x (TV - Physiologic dead space volume)
Minute respiratory volume
TV X RR
Carbon dioxide (as CSF H+)
Stimulates central chemoreceptors in the medulla
Lung zones
Zone 1 (no blood flow), Zone (intermittent blood flow), Zone 3 (continuous blood flow)
Zone 2 and 3, Zone 3, Zone 3 in all areas
Lung zone at the base of the lungs, apex of the lungs, and during exercise respectively
CO2, Acidosis, 2,3, DPG, Exercise, Temperature
CADET face RIGHT – Increase in the ff factors would cause shift to the right of the oxygen-Hgb dissociation curve (unloading of O2 from Hgb)
Carbon monoxide, fetal hemoglobin
Increase in the ff factor would cause shift to the left of the O2-Hgb dissociation curve (increased binding of O2 to Hgb)
Utilization coefficient
Percentage of blood that gives up its oxygen as it passes through the tissue capillaries (25% resting, 75-85% during exercise)
Dorsal respiratory group (DRG) of the medulla
Controls inspiration; sends inspiratory ramp signal
Ventral respiratory group (VRG) of the medulla
Controls both inspiration and expiration; overdrive mechanism in exercise
Pneumotaxic center of the pons
Limits inspiration and increases respiratory rate
Apneustic center of the pons
Stimulates inspiraiton and decreases respiratory rate
Central chemoreceptors
Made up of DRG and VRG in ventral medulla; excited by CSF H+ from blood CO2: adapt within 1-2 days
Peripheral chemoreceptors
Found in carotid bodies (CN IX) and aortic bodies (CN X); ACTIVATED WHEN po2
