The haemodynamic effects of increased intra-abdominal pressure during laparoscopic cholecystectomy in 22 patients were compared with those in 11 patients undergoing open cholecystectomy; bioimpedance cardiography was used for monitoring at predetermined time intervals. In the laparoscopy group stroke volume, cardiac and ejection velocity indices were significantly decreased and the total peripheral resistance index was significantly increased during the insufflation period when compared with preinsufflation and corresponding values in the group undergoing open operation. Routine intraoperative parameters such as heart rate and blood pressure did not show any significant change or indicate alterations in cardiovascular performance during laparoscopic procedures. Continuous non-invasive cardiovascular monitoring by bioimpedance cardiography may be useful in patients with limited cardiac function.