Glucose Homeostasis· Comparison between Hypothermic and Normothermic cardiopulmonary Bypass jean jacques Lehot, M.D., Ph.D.; Hector Piriz, M.D.; jacques VaUard, M.D.; Richard Cohen, Ph.D.; and jeannine Guidollet, M.D. study objectioe: Disturbance in blood glucose homeostasis during cardiac surgery may cause visceral and metabolic alterations. Hypothermic CPR induces glucose and hormonal changes. As normothermic CPR is used at some institutions,. a comparison of blood glucose and plasma hormones between hypothermic and oormothermic CPR was performed. Daign: Prospective nonrandomized stud~ Setting: Univenity cardiac center. ftJtienta: Twenty-two nondiabetic adults undergoing elective coronary bypass and/or valvular surgery. Inlerwntioru: Group I (n 12) underwent hypothermic CPR (25OC) andgroup 2 (n 10) normothermic CPB (3rc). In both groups nonpulsatile CPR was achieved with a membrane oxygenator and dextrose-free crystalloid priming. Dextrose was not administered during surgery but was infused postoperatively (125 mglkWb). Meaurementa and raulta: Eight blood samples were drawn during the period of arrival in the operating room (control) to the third postoperative hour. During hypothermic CPB in group I, blood glucose level increased to 154:t1O mgldl (mean:tSD) associated with a decrease in plasma insulin and an increase in epinephrine, despite a decrease in Cortisol and growth hormone. During rewarming, the blood glucose value continued to increase (to 197:t35 mgldl) associated with an iDcrease in glucagon, growth hormone

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and catecholamine~ despite a 374 percent increase in insulin. During CPR in group 2, insulin, glucagon, cortisol and catecholamines were signi6cantly higher than during hypothermic CPB so that the blood glucose level was not signi6cantly different between the two groups during CPR. Blood glucose value was higher in group I than in group 2 at closure ,0£ the chest (208:t3O vs 175:t 19 mgldl, respectively, p