[Ketamine infusion in tympanoplasty].

The reduction of capillary hemorrhage obtained with ketamine induced us to use this agent in anaesthesia for eardrum plastic surgery. During a period of 8 years 278 operations of this type were performed with this method. Its results were very satisfactory especially with regard to postoperative analgesia. No increase of capillary bleeding was observed after a temporary rise of arterial pressure following induction. Premedication consisted of atropine 0.5 mg intravenous and diazepam (later substituted by midazolam) according to age and weight. Induction was realized with fentanyl 0.1 mg intravenously followed by ketamine 3 mg.kg-1 intravenously. Anaesthesia was maintained by infusion of ketamine (500 mg in 500 ml of saline solution), nitrous oxide-oxygen (50% each) inhalation and pancuronium or vecuronium. Ketamine infusion was stopped approximately 45 min before operation was completed. Most patients regained consciousness in about 15 to 30 min after nitrous oxide was discontinued. Side effects such as bad dreams were noticed only in 29 patients (10.43%). Perturbed recovery from ketamine anaesthesia might be largely prevented by psychological preoperative preparation and adequate dosage of the benzodiazepine used for premedication.