Initial Clinical Effect of Intraportal Insulin Administration on Liver Graft Regeneration in Adult Patients Underwent Living Donor Right Lobe Liver Transplantation

Objective. Insulin is one factor responsible for hepatotrophic regeneration in animal models. This study assessed the clinical effects of intraportal administration of insulin on liver graft regeneration in adult patients undergoing right lobe living donor liver transplantation (LDLT). Methods. Between July 2005 and September 2007, 19 right lobe LDLT adult recipients voluntarily received posttransplant intraportal insulin administration. The present study describes 15 patients without postoperative vascular and bile duct complications, with more than 1 month survival and with complete clinical data who were enrolled to receive intraportal insulin therapy (group 1; n = 15). Another consecutive 15 right lobe LDLT adult recipients without any stimulation regeneration who met the same criteria were enrolled in as noninsulin therapy control group (group NI; n = 15). Group I recipients were treated postoperatively with intraportal insulin infusion, as follows. An 18-gauge catheter was inserted into right gastro-omental vein during surgery, to administer regular insulin just after the operation at the rate of 2 U/h for 1 week. Graft volume (GV) was measured by computed tomography on postoperative days (POD) 7 and 30. Liver functions and serum insulin levels were also measured at POD 7 and POD 30. The liver graft regeneration rate was defined as ratio of posttransplant GV/harvested GV and posttransplant graft-to-recipient weight ratio (GRWR)/operative GRWR. Results. The rate defined as ratio of POD 7 GV/harvested GV among group I was significantly greater than that of group NI (186.07 +/- 35.40% vs 160.61 +/- 22.11%; P < .05). The rate defined as ratio of POD 7 GRWR/operation GRWR was also significantly higher in group I than group NI (178.95 +/- 35.84% vs 156.56 +/- 18.53%; P < .05), whereas there was no significant difference in terms of regeneration rates at 1 month post-LDLT. Intraportal insulin administration may significantly downregulate POD 7 total bilirubin, aspartate aminotransferase, and alanine aminotransferase levels (P < .05). These results suggested that intraportal insulin administration augmented liver regeneration during the first postoperative week by improving hepatic function in LDLT recipients.