Recent studies suggest that significant physiologic derangements can occur during laparoscopic surgery. Eighteen patients admitted for laparoscopic cholecystectomy were studied. The mean age was 46.7 (range 19-78). A standard anesthetic technique, reverse Trendelenburg positioning, and an abdominal insufflation pressure of 15 mmHg with CO2 were used with all subjects. Central venous pressure (CVP) and arterial pressures were measured invasively. Stroke volume and cardiac index were calculated using quantitative transesophageal echocardiography. Baseline measurements were taken after induction. Additional measurements were taken at 15-min intervals throughout the procedure. There was a statistically significant increase in mean arterial pressure (15.9%), systolic blood pressure (11.3%), diastolic blood pressure (19.7%), and CVP (30.0%) from control baseline values. Significant decreases in stroke volume (29.5%) and cardiac index (29.5%) occurred within 30 min of the induction of pneumoperitoneum and positioning (P < 0.05, ANOVA). Laparoscopic cholecystectomy significantly and reversibly decreases cardiac performance. Compromised patients may be at increased risk for complications not previously recognized with this procedure.