Ketamine and Botulinum: A Safe Combinationfor the Management of Childhood Strabismus

AIMS: To determine the prevalence of ketamine side effects in children receiving botulinum toxin injections for strabismus under ketamine anesthesia and to establish the prevalence, severity, and duration of ptosis in these children. METHODS: Children who had undergone ketamine anesthesia for botulinum toxin injections (1999 to 2006) to correct strabismus were identified in a retrospective review. A questionnaire to establish occurrence of nightmares, sleepless nights, hallucinations (ketamine side effects), or ptosis (botulinum toxin side effect), was sent to parents or guardians. Details of side effects were obtained by telephone and the patients' medical records were analyzed. RESULTS: Questionnaires were sent to 113 patients (total of 130 injections). Ninety-seven (114 injections) completed questionnaires were returned. Emergence reactions were experienced by 12 patients (12.4%). Two children experienced sleepless nights, nightmares, and hallucinations. The remaining 10 experienced one side effect only. Eighteen children had ptosis at their 2-week follow-up appointment, most which resolved within 6 weeks. There were no life-threatening or sight-threatening adverse events. CONCLUSIONS: Botulinum toxin injection under intravenous ketamine anesthesia can safely be used for children. Ketamine anesthesia may be associated with side effects, namely hallucinations and sleep disturbances.