The effect of ischemic preconditioning on redox status during liver resections--randomized controlled trial.

Hahn, Oszkár; Blázovics, Anna; Váli, László; Kupcsulik, Peter K

BACKGROUND AND OBJECTIVES Portal clamping during liver resection decreases intraoperative blood loss, but causes ischemic-reperfusion (I-R) injury. Intermittent portal clamping (IPC) and ischemic preconditioning (IP) decreased I-R injury in animal models. Most of the human studies about IP excluded cirrhotic patients, whose liver is more vulnerable to I-R injury. The effect of IP and IPC during extended liver resection was investigated in this randomized controlled trial, with special respect to cirrhotic patients. METHODS One hundred sixty patients (100 normal liver, 60 cirrhotic) undergoing major liver resection were randomized to receive IPC (15 min ischemia, 5 min reperfusion), or IP (10 min ischemia, 10 min reperfusion). Serum oxygen-derived free radicals (ODFR) and antioxidant concentrations (preoperative, after reperfusion and 7th postoperative day), such as "conventional" liver tests (preoperative, 1st, 3rd, and 7th postoperative day) were measured. RESULTS IP resulted in significantly lower peak ODFR, AST, ALT, and bilirubin levels after liver resection than IPC (P < 0.05). The level of serum antioxidants after reperfusion was significantly higher in IP than in IPC groups (P < 0.05). In cirrhotic patients without IP none of these values normalized until the 7th postoperative day. CONCLUSIONS Ischemic preconditioning--especially in patients with liver cirrhosis--is a suitable method to decrease the I-R injury of the liver.