Intraoperative hyperglycemia during infant cardiac surgery is not associated with adverse neurodevelopmental outcomes at 1, 4, and 8 years.

BACKGROUND It is unknown whether intraoperative hyperglycemia in infants is associated with worse neurodevelopmental outcomes after low-flow cardiopulmonary bypass (LF), deep hypothermic circulatory arrest (CA), or both. METHODS In a database review of a prospective trial of 171 infants undergoing arterial switch for D-transposition of the great arteries who were randomly assigned to predominantly LF or CA, glucose was measured after induction (T1), 5 min after cardiopulmonary bypass onset (T2), at the onset of CA or LF (T3), 5 min after CPB resumption (T4), at rewarming to 32 degrees C (T5), 10 min after cardiopulmonary bypass weaning (T6), and 90 min after CA or LF (T7). Outcomes included seizures, electroencephalographic findings, and neurodevelopmental evaluation at 1, 4, and 8 yr. RESULTS Glucose concentrations were affected by support strategy and age at surgery. Lower glucose in the entire group at T6-T7 tended to predict electroencephalographic seizures (P = 0.06 and P = 0.007) but was not related to clinical seizures. Within the predominantly CA group, higher glucose did not correlate with worse outcomes. Rather, it was associated with more rapid electroencephalographic normalization of "close burst" and "relative continuous" activity at all times except T2 (P < or = 0.03), a finding more pronounced in infants aged 7 days old or younger. Intraoperative serum glucose concentrations were unrelated to neurodevelopmental outcomes at ages 1, 4, and 8 yr. CONCLUSIONS Low glucose after cardiopulmonary bypass tended to relate to electroencephalographic seizures and slower electroencephalogram recovery, independent of CA duration. High glucose concentrations were not associated with worse neurodevelopmental outcomes. Avoiding hypoglycemia may be preferable to restricting glucose in infants undergoing heart surgery.