Approach to management of malignant hyperthermia-like syndrome in pediatric diabetes mellitus :

Cerebral edema is an uncommon but devastating complication of diabetic ketoacidosis in children. Risk factors for this complication have not been clearly defined. 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 diabetic ketoacidosis but without cerebral edema were also identified: 181 randomly selected children and 174 children matched to those in the cerebral-edema group with respect to age at presentation, onset of diabetes (established vs. newly diagnosed disease), initial serum glucose concentration, and initial venous pH. Using logistic regression we compared the three groups with respect to demographic characteristics and biochemical variables at presentation and compared the matched groups with respect to therapeutic interventions and changes in biochemical values during treatment. A comparison of the children in the cerebral-edema group with those 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 [representing 1 SD], 3.4; 95 percent confidence interval, 1.9 to 6.3; P<0.001) and higher initial serum urea nitrogen concentrations (relative risk of cerebral edema for each increase of 9 mg per deciliter [3.2 mmol per liter] [representing 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 control group also showed that cerebral edema was associated with lower partial pressures of arterial carbon dioxide and higher serum urea nitrogen concentrations. Of the therapeutic variables, only treatment with bicarbonate was associated with cerebral edema, after adjustment for other covariates (relative risk, 4.2; 95 percent confidence interval, 1.5 to 12.1; P=0.008). Children with diabetic ketoacidosis who have low partial pressures 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.

Cerebral edema during diabetic ketoacidosis (DKA) has been attributed to osmotic cellular swelling during treatment. We evaluated cerebral water distribution and cerebral perfusion during DKA treatment in children. We imaged 14 children during DKA treatment and after recovery, using both diffusion and perfusion weighted magnetic resonance imaging (MRI). We assessed the apparent diffusion coefficients (ADCs) and measures reflecting cerebral perfusion. The ADC was significantly elevated during DKA treatment (indicating increased water diffusion) in all regions except the occipital gray matter. Mean reductions in the ADC from initial to postrecovery MRI were: basal ganglia 4.7 +/- 2.5 x 10(-5) mm(2)/s (P=.002), thalamus 3.7 +/- 2.8 x 10(-5) mm(2)/s, (P=.002), periaqueductal gray matter 4.3 +/- 5.1 x 10(-5) mm(2)/s (P=.03), and frontal white matter 2.0 +/- 3.1 x 10(-5) mm(2)/s (P=.03). In contrast, the ADC in the occipital gray matter increased significantly from the initial to postrecovery MRI (mean increase 3.9 +/- 3.9 x 10(-5) mm(2)/s, P=.004). Perfusion MRI during DKA treatment revealed significantly shorter mean transit times (MTTs) and higher peak tracer concentrations, possibly indicating increased cerebral blood flow (CBF). Elevated ADC values during DKA treatment suggests a vasogenic process as the predominant mechanism of edema formation rather than osmotic cellular swelling.

Diabetic ketoacidosis (DKA) and hyperglycemic hyperosmolar nonketotic syndrome (HHNS) are life-threatening acute metabolic complications of diabetes mellitus. Although there are some important differences, the pathophysiology, the presenting clinical challenge, and the treatment of these metabolic derangements are similar. Each of these complications can be seen in type 1 or type 2 diabetes, although DKA is usually seen in patients with type 1 diabetes and HHNS in patients with type 2 disease. The clinical management of these syndromes involves careful evaluation and correction of the metabolic and volume status of the patient, identification and treatment of precipitating and comorbid conditions, a smooth transition to a long-term treatment regimen, and a plan to prevent recurrence.