Which of the following represents the relationship used by body plethysmography to calculate functional residual capacity?
a. VFRC = ?V ÷ ?P ? (PB – PH2O) c. VFRC = ?V ÷ ?T ? (PB – PH2O)
b. VFRC = ?P ÷ ?V ? (PB – PH2O) d. VFRC = (PB – PH2O) ? ?V
ANS: A
VFRC = ?V ÷ ?P ? (PB – PH2O), where ?V and ?P are the box volume and alveolar pressure changes measured during the panting maneuver, PB is the ambient barometric pressure, and PH2O is the water vapor pressure (assume 47 mm Hg for 37° C).
You might also like to view...
Correct instruction in the technique of incentive spirometry should include which of the follow-ing?
a. Use of accessory muscles at high inspira-tory flows b. Diaphragmatic breathing at slow to mod-erate flows c. "Panting" at volumes approaching total lung capacity d. Use of accessory muscles at low inspira-tory flows
Which of the following is a condition characterized by the absence of menses?
a. Dysmenorrhea b. Menorrhagia c. Polymenorrhea d. Amenorrhea
____ cylinders are used for SCBA units and have an unlimited service life as long as they pass a hydrostatic test every five years.
A. Aluminum B. Steel C. Kevlar D. Fiberglass
A patient with acute intermittent porphyria is deficient in which enzyme?
A. Coproporphyrinogen oxidase B. Aminolevulinic acid synthase C. Ferrochelatase D. Hydroymethylbilane synthase