Relationship between hyperglycemia, hormone disturbances, and clinical evolution in severely hyperglycemic post surgery critically ill children: an observational study.

BACKGROUND

To study hormonal changes associated with severe hyperglycemia in critically ill children and the relationship with prognosis and length of stay in intensive care.

METHODS

Observational study in twenty-nine critically ill children with severe hyperglycemia defined as 2 blood glucose measurements greater than 180 mg/dL. Severity of illness was assessed using pediatric index of mortality (PIM2), pediatric risk of mortality (PRISM) score, and pediatric logistic organ dysfunction (PELOD) scales. Blood glucose, glycosuria, insulin, C-peptide, cortisol, corticotropin, insulinlike growth factor-1, growth hormone, thyrotropin, thyroxine, and treatment with insulin were recorded. β-cell function and insulin sensitivity and resistance were determined on the basis of the homeostatic model assessment (HOMA), using blood glucose and C-peptide levels.

RESULTS

The initial blood glucose level was 249 mg/dL and fell gradually to 125 mg/dL at 72 hours. Initial β-cell function (49.2%) and insulin sensitivity (13.2%) were low. At the time of diagnosis of hyperglycemia, 50% of the patients presented insulin resistance and β-cell dysfunction, 46% presented isolated insulin resistance, and 4% isolated β-cell dysfunction. β-cell function improved rapidly but insulin resistance persisted. Initial glycemia did not correlate with any other factor, and there was no relationship between glycemia and mortality. Patients who died had higher cortisol and growth hormone levels at diagnosis. Length of stay was correlated by univariate analysis, but not by multivariate analysis, with C-peptide and glycemic control at 24 hours, insulin resistance, and severity of illness scores.

CONCLUSIONS

Critically ill children with severe hyperglycemia initially present decreased β-cell function and insulin sensitivity. Nonsurvivors had higher cortisol and growth hormone levels and developed hyperglycemia later than survivors.