respiratory physiology Flashcards
PaO2
partial pressure of dissolved oxygen
SaO2
arterial oxygen saturation
how much of the hemoglobin is bound by oxygen
CaO2
arterial content of oxygen-how much oxygen is present for dL of blood
(also equal to oxygen bound to hemoglobin + oxygen dissolved in blood)
what factors lead to increased ventilation?
increased P CO2
decreased pH
decreased PO2
what controls automatic breathing?
medulla
peripheral chemoreceptor function
short term, transient responses
peripheral chemoreceptors location
common carotid bifurcation
above and below aortic arch
what sets the rhythmicity of breathing?
medulla (pacemaker of the lungs)
central chemoreceptors function
establish resting and long-term response to PaCO2
central chemoreceptor locaiton
near ventral surface of the medulla
what is responsible for inspiration and expiration switching?
pons
bronchiectasis
permanently dilated airways, chronic bronchial inflammation leading to inappropriate clearance of organisms and recurrent infections in the airways
how does cigarette smoking disrupt host defenses?
paralyzes ciliary function
impairs mobility of macrophages and neutrophils
excessive production of mucus
injuring epithelium
ventilation
the process of getting into and out of the alveoli, where the air can participate in gas exchange
tidal volume
Vt, the amount of air inhaled during quiet resting breathing (0.5-0.7L)
minute ventilation
VE, tidal volume x respiratory rate
how much air you move in and out of lungs each minute
anatomic dead space
volume of air that moves in and out of the conducting airways not participating in gas exchange
physiologic dead space
functional measure of the efficiency of the lung in eliminating CO2
in what region is ventilation the greatest in and why?
the lung base
there is increased pressure due to the weight of the lung and more compliant alveoli (bball net)
perfusion
blood flow to the lungs
