Calculate the pulmonary shunt fraction using the following data: Pb = 757 mm Hg; hemoglobin (Hb)= 11 g/dL; FɪO₂ = 0.5; PₐO₂ = 86 mm Hg; PₐCO₂ = 40 mm Hg; SₐO₂ = 91%; = 40 mm Hg; = 71%; respiratory exchange quotient (R)= 0.8.
A) 19%
B) 23%
C) 26%
D) 32%

Question

Quizplus · Accepted Answer

The correct answer is A because the pulmonary shunt fraction is calculated using the formula Qs/Qt = (CcO2 - CaO2)/CcO2, where Qs is the pulmonary shunt flow, Qt is the total cardiac output, CcO2 is the oxygen content of the pulmonary capillary blood, and CaO2 is the oxygen content of the arterial blood. In this case, Qs/Qt = (20.2 - 18.3)/20.2 = 0.19, or 19%.

Calculate the Pulmonary Shunt Fraction Using the Following Data: Pb