Objectives: To determine optimal settings for airway pressure (AWP), pneumoperitoneum pressure (PPP), and central venous pressure (CVP) in pure laparoscopic hepatectomy. Background: High PPP is often employed to control bleeding from the hepatic vein during pure laparoscopic hepatectomy; however, there is a risk of pulmonary gas embolism. We noted that decreases in AWP were often effective. Methods: After establishing carbon dioxide pneumoperitoneum in 6 male piglets and maintaining PPP at 25 mmHg, CVP was measured 3 times at each of 9 levels of airway pressure, which was increased in increments of 5 cmH₂O from 0 to 40 cmH₂O. CVP was measured in the same manner by maintaining PPP at 20, 15, 10, 5, and 0 mmHg, and in laparotomy. Correlation and regression analyses were performed among airway pressure, CVP, and pneumoperitoneum pressure. Results: Positive correlations were observed between AWP and CVP and between PPP and CVP (P < 0.001). Under high airway pressure, CVP was persistently higher than pneumoperitoneum pressure. Under low airway pressure, CVP did not increase or often decreased when PPP was higher than CVP. Conclusions: By increasing pneumoperitoneum pressure, bleeding from the hepatic vein cannot be controlled under high airway pressure, but can be controlled under low airway pressure. However, under low airway pressure, the risk of pulmonary gas embolism increases when PPP is higher than CVP. We consider that reducing AWP is also effective for controlling bleeding from the hepatic vein and safer than increasing pneumoperitoneum pressure.

Laparoscopic hepatectomy has rapidly evolved recently; 1–5 however, laparoscopic anatomical hepatectomy has yet to become widely used, although anatomical hepatectomy is ideal, especially for curative treatment of hepatocellular carcinoma, and is widely accepted via open approach. 6–10 This is because good-experienced skills, for example, exposing Glissonean pedicles and hepatic veins on the cutting plane, are required in order to perform anatomical hepatectomy via a pure laparoscopic approach. We obtained good results for various totally laparoscopic anatomical hepatectomies using the standardized techniques. We exposed the major hepatic veins from the root side by utilizing the unique view from the caudal side in the laparoscopic approach, and moved CUSA from the root side toward the peripheral side to avoid splitting the bifurcation of the hepatic vein. 11–13 We performed totally laparoscopic anatomical hepatectomy for 47 patients from August, 2008, to December, 2012 (Table 1). In most types of anatomical hepatectomy, the mean blood loss was <500 ml. Conversion to open surgery was required in two patients. Postoperative complications were prolonged ascites in two, peroneal palsy in two, and biloma in one. Mortality was zero. The embedded video demonstrates totally laparoscopic right anterior sectorectomy. In conclusion, our standardized techniques make laparoscopic anatomical hepatectomy more feasible. Table 1 The result of 47 patients who underwent totally laparoscopic anatomical hepatectomy Full size table