Dexmedetomidine is a highly selective α2-adrenergic agonist, which is increasingly used in pediatric anesthesia and intensive care. Potential adverse effects that have not been rigorously evaluated in children include its effects on blood glucose and serum potassium concentrations, which are relevant due to the associations of derangements of both parameters with undesired outcomes. We investigated the effects of 3 different doses of dexmedetomidine on these outcomes in a randomized controlled trial in children undergoing elective surgery.
Sixty-four American Society of Anesthesiologists I–II children were randomized to receive either dexmedetomidine 0.25 µg/kg, dexmedetomidine 0.5 µg/kg, dexmedetomidine 0.75 µg/kg, or 0 µg/kg (control), as a bolus administered over 60 seconds after induction of anesthesia. Changes in plasma glucose and serum potassium concentrations were measured in venous blood sampled before and at 15 and 30 minutes after study drug administration. Data were plotted within and between groups and analyzed using a constrained longitudinal data approach.
Forty-nine children completed the study. Mean glucose levels at 15 and 30 minutes were elevated with estimated changes from baseline of 0.37 mmol/L (95% CI, 0.29–0.45 mmol/L) and 0.05 mmol/L (95% CI, 0.00–0.10 mmol/L), respectively. At 15 minutes, there was a linear dose–response relationship (1.07 mmol/L/μg/kg [95% CI, 0.57–1.58 mmol/L/μg/kg]), but there was no appreciable effect of dexmedetomidine at 30 minutes (0.15 mmol/L/μg/kg [95% CI, −0.40 to 0.70 mmol/L/μg/kg]). Potassium levels were depressed relative to baseline, with a mean difference at 15 minutes of −0.20 mEq/L (95% CI, −0.28 to −0.12 mEq/L) and at 30 minutes of −0.12 mEq/L (95% CI, −0.15 to −0.08 mEq/L), but there was no appreciable effect of dexmedetomidine at either time.
Small elevations in glucose and decreases in potassium were observed after induction of anesthesia in children. The elevation in glucose at 15 minutes depended on the dose of dexmedetomidine administered. These preliminary data warrant further investigation.