A new surgical model for hepatectomy in pigs.

BACKGROUND

Anhepatic animal models are suitable for simulating acute liver failure. Hepatectomy in pigs includes en bloc resection of the vena cava, and therefore, a temporary extracorporeal bypass and total clamping of the inferior vena cava are needed. These steps cause severe depression of circulation with impaired survival.

METHODS

Previous to en bloc hepatectomy including retrohepatic vena cava in 20 female pigs, a Y-shaped bypass was implanted starting with end-to-side anastomosis between the vena cava and the portal vein, followed by anastomosis to the intrathoracic vena cava.

RESULTS

Blood flow was constant during and after hepatectomy because vessels were only partially clamped. No venous stasis of intestinal organs was observed. Hemodynamic parameters like heart rate, mean arterial pressure, central venous pressure, pulse oximetry and intracranial pressure remained extremely stabile during and after hepatectomy. Postoperative survival time was 100% after 12 h. Maximum survival time was 84.9 h and mean survival time 51.2 +/- 18.7 h. All animals died from multiple organ failure. Intracranial pressure remained stable during the surgical procedure and rose continuously until death. The autopsy showed massive brain edema.

CONCLUSIONS

This new surgical technique is safe and easy to perform and permits total hepatectomy with minimal blood loss under stable circulation without requiring an extracorporeal bypass.