Effect of insulin therapy on coagulation and fibrinolysis in medical intensive care patients*

Objective:Most intensive care deaths beyond the first few days of critical illness are attributable to nonresolving organ failure, either due to or coinciding with sepsis. One of the mechanisms that is thought to contribute to the pathogenesis of organ failure is microvascular thrombosis. Recently, we reported significant improved survival and prevention of organ failure with the use of intensive insulin therapy to maintain normoglycemia for at least several days. We hypothesize that intensive insulin therapy also prevents severe coagulation abnormalities thereby contributing to less organ failure and better survival. Design:This was a preplanned subanalysis of a large randomized controlled study, conducted at a university hospital medical intensive care unit. The intervention was strict blood glucose control to normoglycemia with insulin. Results:Mortality of intensive insulin-treated patients was lower than that of conventionally treated patients for all classes of upon-admission disseminated intravascular coagulation (DIC) scores, except for those patients with overt DIC scores of 6 or higher (for DIC <5, p = 0.003; for DIC ≥5, p = 0.4). There was no effect of insulin therapy on any of the fibrinolytic, coagulation, or inflammatory parameters tested. Conclusions:This negative observation does not support a key role for these systems in explaining the clinical benefit of intensive insulin therapy, although a short-lived effect within 5 days of treatment cannot be excluded.