Analgesia for adenotonsillectomy in children: a comparison of morphine, ketamine and tramadol

Background : Establishment of good analgesia is of major concern in the postoperative period following adenotonsillectomy. The aim of this study was to compare the effects of ketamine, morphine and tramadol on postoperative pain after adenotonsillectomy in children.

Methods : Sixty children (age 5–12 years) scheduled for adenotonsillectomy were randomized into four groups to receive intravenously (i.v.) either 0.5 mg·kg⁻¹ ketamine hydrochloride (K), 0.1 mg·kg⁻¹ morphine hydrochloride (M), 1.5 mg·kg⁻¹ tramadol hydrochloride (T) or normal saline (S) in a volume of 4 ml during induction. After tracheal intubation 10 μg·kg⁻¹·min⁻¹ ketamine hydrochloride in group K and 0.6 ml·kg⁻¹·h⁻¹ saline i.v. in groups M, K and S were infused peroperatively. Postoperative analgesic requirements and side-effects were recorded. Pain was assessed by the Numeric Rating Scale (NRS) and the Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) scores.

Results : Heart rate increased significantly peroperatively only in group K. NRS at first and fifth minute in group M and at first minute in group T and K and CHEOPS score at first, fifth, 15th and 60th min in group M were found to be significantly lower than in the control group. The time to first analgesic requirement was significantly longer in group M compared with ketamine and the control group. Six children in group M, nine in group T, 11 in group K and 15 in group S needed additional analgesics.

Conclusions : Morphine hydrochloride 0.1 mg·kg⁻¹ i.v. administered during induction of anaesthesia provides efficient pain relief in children undergoing adenotonsillectomy.