Calculating pulmonary shunt fraction using standard clinical measurements.

ABSTRACT: This single-case pedagogical tutorial features a respiratory therapist who underwent a physiological shunt study for departmental education. Four formulas were used to estimate the shunt. A standardized 100% oxygen shunt test in a healthy male adult (51 years old, 185 cm, 84 kg) was performed to demonstrate how equation choice and assumptions affected the results. After 20 min breathing FiO₂ = 1.0 at barometric pressure 752 mmHg, routine blood gas variables (PaO₂ 587 mmHg, PaCO₂ 38 mmHg, SaO₂ 0.993, Hb 15.2 g/dL) were used to compute shunt by four approaches: the classic content equation, Chiang's arterial approximation, a P_AO₂-PaO₂ rule-of-thumb, and a simplified saturation method. Across methods, estimates clust

SUBMITTER: Toffaletti JG 

PROVIDER: S-EPMC12907576 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature