lab 9 respiratory physiology Flashcards
does tidal volume always stay the same?
no
if O2 concentration changes, will this automatically change CO2?
no
are the majority of changes in respiration in response to O2 concentrations?
no
where does gas exchange between air and blood occur?
in alveolar air sacs
what does the efficiency of gas exchange depend on
ventilation
how does a spirometer work?
air breathed through the mesh gives rise to a small pressure difference proportional to flow rate; the pressure differences is transmitted to the spirometer pod and the pressure signal is converted to a changing voltage
how is volume calculated from flow?
it is the integral of flow
does volume of a gas increase or decrease with warming?
increase
is the volume of air expired slightly smaller or larger than the volume breathed in? why?
greater, because the air is warmer
what is tidal volume?
the air drawn into and then expired from the lungs
what is the minute volume?
the amount of air inspired or expired in a minute
what is the volume of air remaining in the lungs after a full expiration?
residual volume
what is the sum of tidal volume and inspiratory reserve capacity?
inspiratory capacity
what is the sum of tidal volume and expiratory reserve capacity?
expiratory capacity
what is expiratory reserve capacity + residual volume?
functional residual capacity
what is inspiratory reserve volume + tidal volume + expiratory reserve volume?
vital capacity
what is vital capacity + residual volume
total lung capacity
what is the general tidal volume of an animal that weighs 100kg?
100kg*10ml/kg=1000ml/min (1L/min)
how does locomotion alter chest cavity size?
extension of the limb results in expansion of the thorax on that side, assisting with respiration
what are normal breath sounds produced by?
tissue vibration, rapid fluctuations of gas pressure and air turbulence
are respiration sounds louder on inspiration or expiration?
inspiration
why are no sounds produced by air movement in and out of the alveoli?
because the air flow is too slow
what is restrictive lung disease?
it is when there is a decrease in the compliance of the lung
when is there optimal gas exchange?
when there is equal perfusion and ventilation
a horse is anesthetized in dorsal recumbency for colic surgery. about an hour into the procedure, the anesthesiologist tells you that V/Q is nearing zero. what does this mean?
this means that ventilation is low while perfusion is high
what is can cause a V/Q ratio of near zero in an anesthetized horse?
the abdomenal cavity is pressing on the lungs, causing decreased lung space (atelectesis), there may also be pooling of blood. as well, resp rate and tidal volume are likely decreased under anaesthesia and so there is not a lot of ventilation
what are examples of physiological shunts?
- bronchiole circulation
- atelectesis
- local vasoconstriction
what is the approximate % concentration of oxygen in room air?
20%
what is the approximate % concentration of CO2 in room air?
0.04%
what is the approximate partial pressure of oxygen?
160mmHg
what is the approximate partial pressure CO2 in room air?
0.3mmHg
what is the partial pressure of CO2 blood
40mmHg
what is the partial pressure of O2 in blood?
90-100 mmHg
a healthy dog is anesthetized for a routine spay. during the procedure gas anesthetic is delivered in oxygen. as the procedure continues minute volume becomes depressed. do you predict that respiratory rate, tidal volume or both would be depressed?
both would be depressed; first, anesthesia is decreasing the action of the respiratory muscles, decreasing the tidal volume; second, the anesthesia is depressing the respiration center, which is causes the centers not to respond to CO2 levels so the resp. rate is slow
a healthy dog is anesthetized for a routine spay. during the procedure gas anesthetic is delivered in oxygen. as the procedure continues minute volume becomes depressed. How would you correct the situation?
ventilate the animal.
