The effects of moderate hypothermia on energy metabolism and serum inflammatory markers during laparotomy

Topical hepatic hypothermia plus ischemic preconditioning: analysis of bile flow and ischemic injuries after initial reperfusion in rats

PURPOSE

To evaluate the effects of the topical liver hypothermia and IPC combination against I/R injury after initial reperfusion.

METHODS

In 32 Wistar rats, partial liver ischemia was induced for 90 minutes in normothermia (IN), ischemic preconditioning (IPC), 26ºC topical hypothermia (H) and 26ºC topical hypothermia plus IPC (H+IPC). MAP, body temperature and bile flow were recorded each 15 minutes. Plasmatic injury markers and tissue antioxidant defenses were assessed after 120 minutes of reperfusion.

RESULTS

MAP and body temperature remained constant during all experiment. Bile flow returned to levels similar to controls after 45 minutes of reperfusion in the H and H+IPC groups and increased significantly in comparison to the NI and IPC groups after 105 and 120 minutes. AST and ALT increased significantly in the normothermic groups in comparison to controls. TBARS levels decreased significantly in the H+IPC group in comparison to the other groups whereas Catalase levels increased significantly in the IPC group. SOD levels were significantly higher in the H group in comparison to all groups.

CONCLUSION

The induction of 26ºC topical hypothermia associated or not to IPC protected the ischemic liver against ischemia/reperfusion injuries and allowed an early recovery of the hepatic function.

Hypothermia: novel approaches for premature infants

Hypothermia for hypoxic ischemic encephalopathy has recently permeated clinical practice for term infants. Speculation regarding a neuroprotective benefit of hypothermia for premature infants with HIE has been raised as a need for further research. Hypothermia for other indications including necrotizing enterocolitis with the hope of tissue preservation following injury is less well studied. A summary of evidence for hypothermia and premature infants is presented in this brief report.

Topic liver hypothermia and ischemic preconditioning: a new model of ischemia and reperfusion in rats

PURPOSE: Evaluation of the Mean Arterial Pressure (MAP) and body temperature changes in a new model of liver ischemia-reperfusion applying topical Hypothermia and Ischemic Preconditioning (IPC). METHODS: Rats (n= 32) were divided in 5 groups: Control (C), Normothermic Ischemia (NI), Ischemic Preconditioning (IPC), Hypothermia 26°C plus IPC (H+IPC) and Hypothermia 26°C (H). MAP and body temperature were recorded at 30 minutes intervals throughout the entire experiment. The study groups underwent 90 minutes partial hepatic ischemia followed by 120 minutes of reperfusion. The median and lateral left lobes were isolated and topical 26°C hypothermia was induced by superfusion of cooled saline solution in H+IPC and H groups. A 10 minutes protocol of ischemia and reperfusion was applied in the IPC and H+IPC groups before the major ischemic insult. RESULTS: There was no significant difference in MAP and body temperature means between the groups throughout the experiments. CONCLUSION: The present model allows the induction of topical hepatic hypothermia associated or not to IPC. New studies to evaluate the possible synergistic effects of these tools can be reproduced without significant changes in macrohemodynamics and body temperature, or in other words, under stable conditions.