The effect of intravenous ketamine plus paracetamol versus intravenous paracetamol alone on postoperative pain, nausea and vomiting after pediatric adenotonsilectomy: a triple blinded randomized clinical trial

Objectives: To assess the effect of intravenous ketamine plus paracetamol versus intravenous paracetamol alone on postoperative pain, nausea and vomiting after pediatric adenotonsilectomy. Design: A triple blinded randomized clinical trial. Setting and conduct: All eligible patients who are candidate for elective adenotonsilectomy and will refer to the Beasat Hospital during the study period will be enrolled in to the trial. Inclusion criteria: (a) 3 to 12 years old; (b) candidate for elective adenotonsilectomy; having one or two criteria based on Physical Status Classification American Society of Anesthesiologists (ASA) Exclusion criteria: (a) history of psychiatric disease; (b) using analgesic within 24 hours before surgery; (c) sensitivity to ketamine or acetaminophen; (d) using cautery for hemostasis. Intervention: Intravenous ketamine 0.25 mg/kg (2 ml) single dose plus intravenous acetaminophen 15 mg/kg single dose, 15 min before the end of surgery and every 6 hours until 24 hours after surgery. Control: Intravenous normal saline 2 ml single dose plus intravenous acetaminophen 15 mg/kg single dose, 15 min before the end of surgery and every 6 hours until 24 hours after surgery. Primary outcome: (a) Pain severity at 0.5, 6, 12, and 12 hours after surgery based on the CHEOPS Pain Score; (b) Number of nausea and vomiting at 0.5, 6, 12, and 12 hours after surgery based on clinical observation. Secondary outcome: The duration of time per min after surgery to using the first narcotic based on medical record.

Vice-chancellor for Research the Technology, Hamadan University of Medical Sciences