Postoperative ketamine analgesia in children: efficacy and safety after halothane anesthesia.

This study was done to investigate the effectiveness and safety of ketamine analgesia after halothane anesthesia for surgery in children. After completion of a surgical procedure, ten children had ketamine (1 mg/kg) injected intravenously during maintenance of anesthesia with 1% halothane in a 60:40 nitrous oxide-oxygen mixture. Cardiovascular parameters measured with noninvasive oscillometry and transthoracic impedance plethysmography remained unchanged after administration of ketamine. Excellent analgesia and a calm anesthetic recovery were produced, without detectable cardiovascular depression. When ketamine and halothane are administered in combination, careful restriction of dosages of these agents is recommended. Interaction of higher doses of ketamine and halothane has been reported to produce hypotension and bradycardia, which can be avoided with use of subdissociative, analgesic doses of ketamine during light halothane maintenance before emergence. After halothane anesthesia in healthy children, ketamine may be considered a suitable alternative to narcotics for postoperative analgesia.