Term
| How do you calculate ventilation? |
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Definition
volume x frequency
(volume per time)
ml/min |
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Term
| The total volume of air in the lung is partitioned into what four primary volumes? |
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Definition
| Tidal volume, inspiratory reserve volume, expiratory reserve volume, residual volume |
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Term
| What is the average tidal volume? |
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Definition
Vt = 500 mL
tidal volume = volume of air inhaled and exhaled during one breath |
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Term
| What is the average inspiratory reserve volume? |
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Definition
IRV = 3000 mL
IRV = the volume of air that can be inspired above tidal volume |
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Term
| What is the average expiratory reserve volume? |
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Definition
ERV = 1300 mL
ERV = the volume of air that can be expired below tidal volume |
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Term
| What is the average residual volume? |
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Definition
RV = 1200 mL -
RV = the volume of air remaining in the lung that cannot be exhaled |
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Term
| What cannot be measured using a spirometer? |
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Definition
| total lung capacity, functional residual capacity, residual volume |
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Term
| What is the functional residual capacity? |
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Definition
FRC = the volume of air in lungs when you are not trying to inhale or exhale
FRC = ERV + RV = 2500 mL |
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Term
| What is the vital capacity? |
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Definition
| Vital capacity = the maximum range of volumes reached by inspiratory and expiratory efforts Vital capacity = IRV + Vt + ERV = 4800 mL |
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Term
| What is total lung capacity and what is its average volume? |
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Definition
Total lung capacity is the maximum amount of air that can be voluntarily inspired.
TLC = IRV + Vt + ERV +RV = 6000 mL |
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Term
| What are the four primary lung capacities? |
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Definition
functional residual capacity, inspiratory capacity, vital capacity, total lung capacity
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Term
| What is the inspiratory capacity? |
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Definition
IC is the maximum range of volumes reached by inspiratory efforts
IC = Vt + IRV = 3500 mL |
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Term
| What two ways can you measure residual volume? |
|
Definition
Helium gas dilution technique:
C1 x V1 = C2 x (V1 + V2)
Body plethysmograph:
P1V1 = P2V2 (Boyle's Law) |
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|
Term
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Definition
| V = volume and 'dot' stands for "per unit time" ... so it is referring to the total amount of air moved in or out of the lungs per unit time (usually one minute) |
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Term
| What is total ventilation (VdotE) ? |
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Definition
| total ventilation is equal to dead space ventilation plus alveolar space ventilation |
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Term
| What is effective ventilation? ineffective ventilation? |
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Definition
effective = alveolar ventilation
ineffective = dead space ventilation |
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Term
| How is alveolar ventilation related to concentration of CO2 in the exhaled air? |
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Definition
| it is inversely related -- as CO2 increases, alveolar ventilation decreases |
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Term
| What is the best clinical measure of effective ventilation? |
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Definition
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Term
| What pressure of CO2 in arterial blood is considered to be hypercapnia/acidosis? |
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Definition
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Term
| what is the capacity of the anatomical dead zone? |
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Definition
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Term
| what is the clinical expedient for measuring anatomic dead space ? |
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Definition
| pts weight in lbs = mL dead space |
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Term
| What methods are used to measure anatomic dead space? |
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Definition
| oxygen inhalation (Fowler's technique) or nitrogen washout |
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Term
| how much of the normal tidal volume inspiration is "dirty" air? |
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Definition
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Term
What is the normal percentage of nitrogen concentration in the alveolar space?
What about after Fowler's method? |
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Definition
normal -- 80%
After Fowler's method -- 40%
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|
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Term
| what is physiologic dead space? |
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Definition
| it the volume of anatomic dead space plus the volume of alveolated airways that have poor pulmonary perfusion |
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Term
| what is the volume of physiologic dead space? |
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Definition
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Term
| which part of the lung has the greatest ventilation? |
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Definition
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Term
| what is the anatomical reason that the base of the lung receives the highest ventilation? physiological reason? |
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Definition
| it has the most lung tissue; gravity |
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Term
| where in the lung are alveoli most compliant? |
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Definition
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