Laparoscopic cholecystectomy (LC) has been widely accepted as an alternative to laparotomy and has many advantages, including short hospital stay and very limited surgical invasion. However, this procedure may impair hepatic function in elderly patients because high pressure is maintained in the peritoneal cavity for an extended period. We observed the effect of pneumoperitoneum on the middle hepatic venous blood flow (MHVBF) in elderly patients undergoing LC. LC patients were anesthesized with inhaled and epidural anesthesia, after which MHVBF was continuously measured by transesophageal echocardiography. MHVBF decreased significantly during a period of high intraperitoneal pressure, and recovery of MHVBF after deflation was significantly lower in elderly patients (65-75 yr), but not in younger patients (24-62 yr). In contrast, MHVBF remained almost constant in elderly patients during open cholecystectomy, and thus was significantly different from that in patients who underwent LC with pneumoperitoneum. Laparoscopic cholecystectomy may impair hepatic function in elderly patients because high pressure is maintained in the peritoneal cavity for an extended period.