Flashcards in Phys: Respiratory Phys Deck (33)
fxn of lungs?
what is gaseous exchange dependent on?
ventilation- amount of gas delivered by the lungs
perfusion- amount of blood delivered by the heart to the lungs
diffusion- amount of gas that passes thru the air-blood barrier
perfusion is greatest?
base- wasted perfusion
ventilation is highest?
apex- wasted ventilation
air- blood barrier is made up of?
capillary endothelium, basement membrane, type I pneumocyte
what are type II pneumocyte fxn?
make the surfactant, which reduces the surface tension in the alveoli
what is ficks law?
rate of diffusion through a membrane is inversely proportional to the thickness of the membrane
ventilation/perfusion rate is?pulmonary BF rate is?
4 L/min; 5 L/min- 4L/5L=0.8
highest is Apex -3
lowest in Base - 0.6
what is meant by "a shift to the right" regarding oxygen
decrease Hb affinity for O2, therefore O2 is released
what are the 4 factors for a shift to the right
97% of the oxygen in blood is carried by?
CO2 is transported by?
23% attached to hhemoglobin as cardaminohemoglobin
7% dissolved in plasma
what does lipoprotein do?
keeps lung exoanded by dec surface tension
what is partial pressure?
O2 conc. in the alveoli
rate of absorption of O2 in blood
rate of entry of new O2 into lungs bu breathing
on inspiration the diaphragm does what?
when pressure dec. - air moves into lungs
volume of a normal breath
inspiratory reserve volume
volume inspired above TV
expiratory reserve volume
volume expired after normal breath
what resides in the lungs
functional resdiual capacity
air left in lungs after normal expiration
volume expired after maximal inspiration
total lung capacity
pneumotaxic center does?
turns off inspiratory center before overexpansion of lungs occur
herring -breuer reflex is?
stretch receptors- bronchi PREVENT over stretching of lungs
apneustic center does?
prevents turn off of inspiratory center
Bohr effect is?
CO2 enters blood stream, causing O2 disassociation from hemoglobin
haldene effect does?
CO2 combines with hemoglobin to form more bicarbonate ions
what is the major determinant of breathing?
conc. of CO2 in the blood
Cheyne-stokes breathing is?
periods of rapid breathing w/ increasing then decreasing TV followed by apnea (seen in CHF)
Kussmaul breathing is?
deep rapid regular breathing