Moderate hypothermia ameliorates liver energy failure after intestinal ischaemia-reperfusion in anaesthetised rats

Background/Purpose: Intestinal ischaemia-reperfusion (IR) can cause liver failure. The aims of this work were to study the effects of intestinal IR on liver energy metabolism and to evaluate the effects of moderate hypothermia. Methods: Intestinal IR (90-minute intestinal ischaemia plus 60-minute or 240-minute reperfusion) was achieved by clamping and unclamping the superior mesenteric artery in rats. Normothermia or moderate hypothermia (30 degrees to 33 degreesC) was maintained by adjusting the environmental temperature. The ratio of hepatic inorganic phosphate to adenosine triphosphate (ATP) was monitored continuously during intestinal IR using in vivo phosphorus (P-31) magnetic resonance spectroscopy, Phosphorus metabolites also were measured in extracts prepared from freeze-clamped liver and intestine. Results: Mortality occurred exclusively during normothermic intestinal IR. A progressive increase in the hepatic inorganic phosphate to ATP ratio after normothermic intestinal IR was observed. Moderate hypothermia delayed this effect. Analysis of liver extracts confirmed above findings. However, there was no difference in intestinal phosphocreatine or ATP between normothermic and hypothermic rats undergoing intestinal IR. Conclusions: Intestinal IR at normothermia was associated with liver energy failure and high mortality rate. Moderate hypothermia ameliorated liver energy failure but did not attenuate intestinal energy failure after intestinal IR. Hypothermia may prove to be useful in the management of patients with intestinal IR injuries in the future. Copyright (C) 2001 by W.B. Saunders Company.