Mild hypothermia attenuate kidney injury in canines with oleic acid-induced acute respiratory distress syndrome.

Abstract

BACKGROUND: Hypothermia may attenuate ventilator induced-lung injury in acute respiratory distress syndrome (ARDS). However, the impact of hypothermia on extra-pulmonary organ injury in ARDS remains unclear. The purpose of this study was to investigate whether hypothermia affects extra-pulmonary organ injury in a canine ARDS model induced by oleic acid. OBJECTIVES: Twelve anesthetized canines with oleic acid-induced ARDS were randomly divided (n=6 per group) into a hypothermia group (core temperature of 33&#xb1;1&#xb0;C, HT group) and a normothermia group (core temperature of 38&#xb1;1&#xb0;C, NT group) and treated for four hours. The liver, small intestine and kidney were assessed by evaluating biochemical parameters, plasma and tissue cytokine levels, and tissue histopathological injury scores. RESULTS: The HT group showed a lower plateau pressure, lung elastance and pulmonary vascular resistance. Hypothermia was associated with lower oxygen consumption (138.4&#xb1;55.0mlmin(-1)vs. 72.0&#xb1;11.2mlmin(-1), P<0.05) and higher oxygen saturation of mixed venous blood (62.8%&#xb1;8.0% vs. 77.5%&#xb1;10.1%, P<0.05). Both groups had similar levels of tumour necrosis factor-&#x3b1; in the plasma and extra-pulmonary organ, however, plasma interleukin-10 (97.1&#xb1;25.0pgml(-1)vs. 131.4&#xb1;27.0pgml(-1), P<0.05) was higher in the HT group. Further, the animals in the HT group had a lower levels of plasma creatinine (54.6&#xb1;19.1UL(-1)vs. 29.1&#xb1;8.0UL(-1), P<0.05), and lower renal histopathological injury scores [4.0(3.5;7.0) vs. 1.5(0.8;3.0), P<0.05]. Hypothermia did not affect the histopathological injury of the liver and small intestine. CONCLUSIONS: Short-term mild hypothermia can reduce lung elastance and pulmonary vascular resistance, increase the systemic anti-inflammatory response and attenuate kidney histopathological injury in a canine ARDS model induced by oleic acid.