Conséquences cardiovasculaires de l’hypothermie
Hypothermia, defined as body temperature equal to or inferior to 35℃ is often encountered in the intensive care patients. It can be accidental or therapeutic, in which case it plays a role in certain ischemia-reperfusion processes. Hypothermia has multiple cardiac and vascular effects including initial tachycardia followed by bradycardia; a preservation of myocardial contractility in case of mild or moderate hypothermia, and an initially stable or decreased cardiac index that decreases further during profound hypothermia; a decrease in myocardial and overall metabolic requirements with an increase in SvO2 resulting in a favorable or stable ratio of oxygen delivery/consumption despite the usual hypoxia-hypocapnia; an increase in overall vascular resistance despite a decrease in sensitivity to exogenous catecholamines; a tendency to hypovolemia essentially due to coldinduced diuresis.