Normothermic hepatic vascular exclusion for extensive hepatectomy

Area of Science:

• Hepatobiliary Surgery
• Surgical Oncology
• Transplantation Immunology

Background:

• The liver's tolerance to warm ischemia remains controversial, with current practices often recommending hypothermia to prevent anoxic damage.
• Hepatic vascular isolation is used in liver resections, but adjuncts like chilled infusions are debated.
• Extensive hepatic resection for tumors presents challenges, including significant blood loss and risks associated with prolonged ischemia.

Purpose of the Study:

• To evaluate the safety and feasibility of complete hepatic vascular exclusion without hypothermia during extensive liver resections.
• To assess the liver's tolerance to prolonged periods of normothermic warm ischemia in patients undergoing major liver surgery.
• To determine if extended warm ischemia times are safe for patients with hepatic tumors, particularly those with hypervascularity.

Main Methods:

• Fourteen patients with hepatic tumors underwent extensive hepatic resection utilizing complete hepatic vascular exclusion.
• The procedure was performed without the use of intraportal or intra-arterial chilling (hypothermia).
• Hemodynamic monitoring, including pulmonary artery pressure, was carefully maintained throughout the procedure.

Main Results:

• Complete hepatic vascular exclusion without refrigeration significantly reduced blood loss during resection of large, hypervascular hepatic tumors.
• The procedure enhanced the safety of hazardous lobectomies.
• Hepatic tolerance to prolonged warm ischemia, up to 65 minutes, was found to be surprisingly good in the absence of preoperative hepatic dysfunction.
• No anoxic hepatocellular damage was observed within the studied ischemia time frame.

Conclusions:

• Complete hepatic vascular exclusion without hypothermia is a safe and effective technique for extensive liver resection, especially for large or hypervascular tumors.
• Prolonged normothermic hepatic ischemia of up to 65 minutes can be safely tolerated by the liver in the absence of significant preoperative hepatic dysfunction.
• The findings suggest that the traditional 15-20 minute limit for normothermic hepatic ischemia can be extended to approximately one hour when clinically necessary, improving surgical options for complex liver resections.