Mechanics Flashcards
What is a normal inspiratory reserve volume?
1.9 to 2. 5 liters
What is a normal tidal volume?
0.4 to 0.5
What is a normal expiratory reserve volume?
1.1 to 1.5
What is a normal residual volume?
1.5 to 1.9
What is a normal total lung capacity?
4.9 to 6.4
What is a normal inspiratory capacity?
2.3 to 3.0
What is a normal functional residual capacity?
2.6 to 3.4
What is a normal vital capacity?
3.4 to 4.5
What are three important features of gases that can be derived from the Ideal Gas Law?
- a gas will exert a pressure or a force per unit area. 2. a gas occupies a volume, expressed in liters. 3. the volume of a gas is directly proportional to its temperature and inversely proportional to the pressure.
What is the re-written version of the ideal gas law, where concentration is written as a constant?
P = RTC
What is total pressure equal to in the gas fraction equation?
1.0 Sum of all partial pressures must equal one
What is Dalton’s Law?
PB=PN2+PO2+PCO2+PH2O
When is water vapor pressure included in the Dalton’s Law equation?
when calculating for saturated air, i.e. in the body.
What is the fractional gas concentration (Fg) equation?
Fg = Pg/PB Where Pg is the gas partial pressure sum and Pb is barometric pressure
What does BTPS stand for?
body temperature, ambient pressure and saturated with water vapor. Volumes of ventilated gas are typically expressed in BTPS conditions (e.g., pulmonary ventilation, tidal volume).
What does STPD stand for?
standard temperature (0 ̊C or 273 ̊K), standard pressure (760 mmHg) and dry (no water vapor present). Metabolic rates (oxygen consumption and carbon dioxide production) are expressed as gas volumes in STPD conditions since volumes at STPD are directly related to the number of millimoles of oxygen consumed or carbon dioxide produced (22.4 ml per mmole).
What does ATPS stand for?
ambient temperature, ambient pressure and saturated with water vapor. Many respiratory variables are measured in ATPS conditions and must be converted to BTPS or STPD conditions as appropriate.
Henry’s Law describes the concentration of a dissolved gas in solution (Cg). What is the equation?
Cg = K * Pg where K is the solubility constant (specific to a certain temperature, solvent and gas) and Pg is the gas pressure in contact with the solvent
What is tidal volume?
the change in volume with quiet inspiration and expiration

What is inspiratory reserve volume?
the additional air that can be inspired with additional effort (max)

What is residual volume?
the air that can never be expelled from thelung, no matter how much effort is expended

What is functional residual capacity?
The sum of the expiratory reserve volume and the residual volume, i.e. all the air in the lung left after quiet expiration

What is inspiratory capacity?
All the air that could go in the lung after quiet expiration, i.e. the sume of tidal volume and inspiratory reserve volume

What is vital capacity?
The total air that can move in and out of the lungs in physiologic conditions , ie. the sum of inspiratory capacity, expiratory residual volume and inspiratory residual volume






