Pain prevention with intraoperative ketamine in outpatient children undergoing tonsillectomy or tonsillectomy and adenotomy.

STUDY OBJECTIVES: To evaluate the effectiveness of ketamine in the prevention of postoperative pain after tonsillectomy.

DESIGN: Randomized, prospective, double-blind study.

SETTING: University hospital.

PATIENTS: 90 ASA physical status I and II patients, aged 5 to 15 years, scheduled for tonsillectomy or adenotonsillectomy.

INTERVENTIONS: Patients were divided into three groups. The pain preventive group received intravenous (IV) ketamine 0.5 mg/kg in 2 mL saline before the tonsils were surgically removed, followed by a continuous IV infusion of ketamine at 6 micro/(kg/min). In the ketamine group, 2 mL saline was given before the tonsils were surgically removed; saline infusion (10 mL/h) was continued until bleeding control, and 0.8 mg/kg ketamine was given during bleeding control in 2 mL saline. In the control group, only saline was given.

MEASUREMENTS AND MAIN RESULTS: Cardiorespiratory system data, recovery from anesthesia and discharge parameters, tramadol requirement, and complications were recorded. Recovery from anesthesia and discharge parameters were similar among the groups. Total dose of tramadol was lower in the pain preventive group than in the other groups. In the pain preventive group, verbal pain scale scores were lower in the early postoperative period in the fourth and sixth hours (P < 0.05).

CONCLUSIONS: Ketamine decreases postoperative analgesic requirements and has analgesic effects when used before surgery in tonsillectomy/adenotonsillectomy.