EVALUATION OF MIXED VENOUS OXYGEN-SATURATION IN CHRONIC SEVERE MITRALREGURGITATION

Objective: The objective of this study was to evaluate whether chronic severe mitral regurgitation leads to an artifactual elevation of mixe d venous oxygen saturation. Design: Prospective study. Setting: Univer sity hospital setting. Participants: Thirty patients with chronic seve re mitral regurgitation undergoing surgery on the mitral valve and 25 patients without mitral regurgitation scheduled for elective coronary artery surgery. Interventions: Blood samples were simultaneously withd rawn from the distal port and the paceport of a pulmonary artery cathe ter. Measurements and Main Results: During steady-state anesthesia. ox ygen saturation and hemoglobin concentration were measured. There was no difference between mean oxygen saturation in blood from the pulmona ry artery and the right ventricle in patients with mitral regurgitatio n, no matter whether large v waves were present, and in patients witho ut mitral regurgitation. The distribution of individual differences be tween mixed venous and right ventricular oxygen saturation did not dif fer between groups. Conclusions: Because mixed venous oxygen saturatio n is not affected by chronic severe mitral regurgitation, it can be us ed in patients with mitral regurgitation just as in patients without m itral regurgitation. Copyright (C) 1996 by W.B. Saunders Company