[The prevention of postoperative vomiting following strabismus surgery in children]

Abstract

Children recovering from anaesthesia for strabismus surgery are particularly prone to nausea and vomiting as a result of intraoperative vagus irritation. Besides being disturbing to the patient, vomiting can be dangerous during emergence from anesthesia and can result in delayed discharge. Droperidol is a powerful antiemetic drug that has been shown to reduce the incidence and severity of postoperative nausea and vomiting in pediatric strabismus patients, although the best timing for administration is not clear. MATERIAL AND METHODS. We compared three randomized groups totalling 61 patients. Droperidol 0.075 mg/kg i.v. was given either at induction of anesthesia after intubation (n = 20) or during the last muscle suture (n = 21). The third group received no antiemetic treatment. The patients' ages ranged from 3 to 14 years (mean 5.9 +/- 2.84 years). There was no difference in age or sex between the three groups. Anesthesia was standardized with rectal midazolam premedication, atropine, thiopental, succinylcholine, O2/N2O = 1:2, enflurane, intubation, and a gastric tube. RESULTS. Nausea, retching, or vomiting occurred in 2/20 children (10%) given droperidol preoperatively, 4/21 children (19%) with droperidol during the operation, and 9/20 children (45%) with no antiemetic treatment. The difference between groups I and III was significant (p less than 0.05). Comparison of groups II and III and groups I and II showed no statistical significance. Operation time was similar in each group and there was no delay in time of extubation. In each group 1 case of hypotension occurred. No child showed extrapyramidal symptoms. The lower incidence of vomiting in all study groups compared to the literature is thought to be due to three factors: (1) emptying the stomach at the end of the operation by a gastric tube, which is removed before extubation; (2) avoidance of opioids; (3) surgical procedure being done by a very experienced surgeon in 57/61 children (12 vomiting versus 45 not vomiting) in contrast to 3/4 children vomiting postoperatively after surgery by a less experienced surgeon. CONCLUSIONS. We recommend preoperative droperidol 75 micrograms/kg i.v. as the best prophylaxis of postoperative emesis without severe side effects in pediatric strabismus surgery.