Simultaneous operation for cardiac disease and gastrointestinal malignancy.

AIM: To investigate the safety of performing simultaneous cardiac surgery and a resection of a gastrointestinal malignancy. METHODS: Among 3664 elective cardiac operations performed in adults at Kagoshima University Hospital from January 1991 to October 2009, this study reviewed the clinical records of the patients who underwent concomitant cardiac surgery and a gastrointestinal resection. Such simultaneous surgeries were performed in 15 patients between January 1991 and October 2009. The cardiac diseases included 8 cases of coronary artery disease and 7 cases with valvular heart disease. Gastrointestinal malignancies included 11 gastric and 4 colon cancers. Immediate postoperative and long-term outcomes were evaluated. RESULTS: Postoperative complications occurred in 5 patients (33.3%), including strokes (n = 1), respiratory failure requiring re-intubation (n = 1), hemorrhage (n = 2), hyperbilirubinemia (n = 1) and aspiration pneumonia (n = 1). There was 1 hospital death caused by the development of adult respiratory distress syndrome after postoperative surgical bleeding followed aortic valve replacement plus gastrectomy. There was no cardiovascular event in the patients during the follow-up period. The cumulative survival rate for all patients was 69.2% at 5 years. CONCLUSION: Simultaneous procedures are acceptable for the patients who require surgery for both cardiac diseases and gastrointestinal malignancy. In particular, the combination of a standard cardiac operation, such as coronary artery bypass grafting or an isolated valve replacement and simple gastrointestinal resection, such as gastrectomy or colectomy can therefore be safely performed.

Porcine model of auxiliary partial orthotopic liver transplantation for acute liver failure.

BACKGROUND: Auxiliary partial orthotopic liver transplantation (APOLT) has been an effective alternative in acute liver failure (ALF), but clinically several problems remain to be resolved. Thus, we attempt to establish an APOLT model for ALF using a large animal and demonstrate the validity of our model. METHODS: In experiment 1, we created an animal model of ALF using pig. ALF was induced by resection of 70% of the whole liver under total hepatic vascular exclusion (THVE). The duration of ischemia was 90 minutes. In experiment 2, we tried to make an APOLT model by using this ALF model as a recipient. That is, during 90 minutes of THVE, 70% hepatectomy and subsequent partial orthotopic transplantation was completed. RESULTS: In experiment 1, six of seven pigs died within three days with jaundice and massive ascites. Based on microcirculatory disturbance of the remnant liver and hepatocellular necrosis, 70% hepatectomy with 90 minutes of THVE was considered a proper model of ALF. In experiment 2, six out of seven APOLT model animals survived more than four days. T. Bil levels in the APOLT model remained consistently within the normal range throughout the observation period. In immunohistochemistry, several labeled nuclei stained with Ki67 were identified in native liver of the APOLT model. CONCLUSIONS: This APOLT procedure provided temporary liver function support and enabled the recipient to survive until the failing native liver had regenerated. Our APOLT model could be suitable and useful for understanding the role of APOLT in ALF.

Advantage of ischemic preconditioning for hepatic resection in pigs.

BACKGROUND: Ischemic preconditioning (IP) and intermittent inflow occlusion (IO) have provided beneficial outcomes in hepatic resection. However, comparison of these two procedures against warm hepatic ischemia-reperfusion injury has not been studied enough. MATERIALS AND METHODS: Pigs that had undergone 65% hepatectomy were subjected to Control (120 min continuous ischemia, n = 6), IP (10 min ischemia and 10 min reperfusion, followed by 120 min continuous ischemia, n = 6), and IO (120 min ischemia in the form of eight successive periods of 15 min ischemia and 5 min reperfusion, n = 6). We evaluated hepatocyte injury by aspartate aminotransferase, lactate dehydrogenase and hepaplastin test, hepatic microcirculation by hepatic tissue blood flow (HTBF) and endothelin (ET)-1, inflammatory response by tumor necrosis factor-alpha (TNF-alpha), and histopathology after reperfusion. RESULTS: IP prevented hepatocyte injury, HTBF disturbance, and hepatocyte necrosis in histopathology as well as IO. These two groups showed significantly better outcomes than Control. IP produced significantly less ET-1 and TNF-alpha than IO. CONCLUSIONS: IP ameliorated hepatic warm ischemia-reperfusion injury. Furthermore, IP gained more advantages in preventing chemokine production such as ET-1 and inflammatory response over IO. IP could take the place of IO for hepatectomy.

Serotonin activity and liver dysfunction following hepatic ischemia and reperfusion.

Serotonin (5-hydroxytriptamine; 5-HT), which is stored in platelets, is known to induce vasoconstriction and promote platelet aggregation. More recent studies suggest that serotonin also plays a role in organ injury after ischemia and reperfusion. The purpose of this study was to characterize the role of 5-HT and platelet function in the pathogenesis of hepatic ischemia-reperfusion injury. Under the portocaval shunt, 60 or 90 min of complete warm ischemia of canine liver was induced by Pringle's maneuver, followed by reperfusion for 120 min. Time-matched, sham-operated animals served as controls. Hepatic tissue blood flow and various parameters of hepatic vein blood (ALT, LDH, platelet count and platelet aggregation) were measured before and after reperfusion. 5-HT levels in portal vein and hepatic vein were also assayed. Hepatic ischemia and reperfusion resulted in liver hypoperfusion, hepatocellular dysfunction, increased platelet aggregation, increased 5-HT levels, and hepatic microcirculation injury. These results suggest that the endogenous 5-HT released from platelet may contribute to liver tissue hypoperfusion following hepatic ischemia-reperfusion.