Calculate the pulmonary shunt fraction using the following data: Pb = 757 mm Hg; hemoglobin (Hb) = 11 g/dL; FIO2 = 0.5; PaO2 = 86 mm Hg; PaCO2 = 40 mm Hg; SaO2 = 91%; = 40 mm Hg; = 71%; respiratory exchange quotient (R) = 0.8

The purpose of administering humidified oxygen in the treatment of asthma is to:

a. dilate the bronchi. b. avoid drying of mucus secretions in the airway. c. increase the respiratory rate. d. correct alveolar dehydration.

Many enzymes in the blood plasma show maximum activity in which of the following pH ranges?

A. 4 to 5 B. 6 to 7 C. 7 to 8 D. 8 to 9