Analgesic and respiratory effect of nalbuphine and pethidine for adenotonsillectomy in children with obstructive sleep disorder.

Opioids may depress respiration and contribute to airway obstruction after adenotonsillectomy for obstructive sleep disorder. We compared the respiratory and analgesic effects of nalbuphine, which has a ceiling effect for respiratory depression, and pethidine in 90 children (aged 2-12 years) with a history of obstructive sleep disorder undergoing adenotonsillectomy. Children were scored for their obstructive sleep disorder history and were randomly allocated to receive intravenously at induction of anaesthesia either nalbuphine 0.1 mg.kg-1 (group N) or pethidine 1 mg.kg-1 (group P). End-tidal carbon dioxide was measured in the recovery period using a nasopharyngeal catheter and oxygen saturation whilst breathing air; pain and sedation scores were recorded for 6 h postoperatively. Both groups were similar with respect to the demographic data and respiratory measurements: mean (SD) oxygen saturation on air in the recovery area (96.2% (1.2) vs. 96.5% (1.1) in group N and P, respectively) and mean (SD) end-tidal carbon dioxide (46.4 (5.5) mmHg vs. 47.7 (4) mmHg in group N and P, respectively). High obstructive sleep disorder score, history of apnoea, hyperactivity and loud snoring were found to be the best predictors of early postoperative oxygen desaturation in both groups.