Risk factors for cerebral edema in children with diabetic ketoacidosis

Background: Cerebral edema is an uncommon but devastating complication of d iabetic ketoacidosis in children. Risk factors for this complication have n ot been clearly defined. Methods: In this multicenter study, we identified 61 children who had been hospitalized for diabetic ketoacidosis within a 15-year period and in whom cerebral edema had developed. Two additional groups of children with diabet ic ketoacidosis but without cerebral edema were also identified: 181 random ly selected children and 174 children matched to those in the cerebral-edem a group with respect to age at presentation, onset of diabetes (established vs. newly diagnosed disease), initial serum glucose concentration, and ini tial venous pH. Using logistic regression, we compared the three groups wit h respect to demographic characteristics and biochemical variables at prese ntation and compared the matched groups with respect to therapeutic interve ntions and changes in biochemical values during treatment. Results: A comparison of the children in the cerebral-edema group with thos e in the random control group showed that cerebral edema was significantly associated with lower initial partial pressures of arterial carbon dioxide (relative risk of cerebral edema for each decrease of 7.8 mm Hg [representi ng 1 SD], 3.4; 95 percent confidence interval, 1.9 to 6.3; P<0.001) and hig her initial serum urea nitrogen concentrations (relative risk of cerebral e dema for each increase of 9 mg per deciliter [3.2 mmol per liter] [represen ting 1 SD], 1.7; 95 percent confidence interval, 1.2 to 2.5; P = 0.003). A comparison of the children with cerebral edema with those in the matched co ntrol group also showed that cerebral edema was associated with lower parti al pressures of arterial carbon dioxide and higher serum urea nitrogen conc entrations. Of the therapeutic variables, only treatment with bicarbonate w as associated with cerebral edema, after adjustment for other covariates (r elative risk, 4.2; 95 percent confidence interval, 1.5 to 12.1; P = 0.008). Conclusions: Children with diabetic ketoacidosis who have low partial press ures of arterial carbon dioxide and high serum urea nitrogen concentrations at presentation and who are treated with bicarbonate are at increased risk for cerebral edema. (N Engl J Med 2001;344:264-9.) Copyright (C) 2001 Mass achusetts Medical Society.