Safety and efficacy of alfentanil and halothane in paediatric surgical patients

Abstract

Alfentanil, a congener of the opioid fentanyl, possesses properties that make it an attractive choice for use during short operative procedures. Since the phannacodynamic aspects of alfentanil have not been well documented in children, this study was undertaken to evaluate the safety, efficacy, and dose requirements of alfentanil when used with nitrous oxide or halothane in paediatric patients. Eighty unpremedicated patients, ASA physical status I or II and aged 2-12 yr were studied. Patients were randomly assigned to one of four groups. After induction of anaesthesia with nitrous oxide, oxygen, and halothane, the groups were treated as follows. In Group I (n = 19), after halothane was discontinued, alfentanil 50 μg · kg-1 was infused over 30 sec. In Group 2 (n = 20), the end-tidal halothane was maintained at 0.5% and alfentanil 25 μg · kg-1 was infused. In Group 3 (n = 20), the end-tidal halothane concentration was maintained at 1% and alfentanil 12.5 μg · kg-1 was infused. In Group4(n = 21), the end-tidal halothane concentration was maintained at 1.5% and no alfentanil was administered. Patients in Groups 1, 2, and 3 received bolus doses of alfentanil 12.5 μg · kg-1 as needed to maintain haemodynamic stability. After alfentanil administration, there were transient decreases in systolic blood pressure in Groups 1 and 2, and in heart rate in Group 2. With surgical stimulation, haemodynamic stability was well maintained except in patients in Group 1, who had an increase in systolic blood pressure. Children Group 1 were alert sooner and their tracheas were extubated earlier than those in Groups 2, 3, and 4. The four groups were similar in postoperative narcotic analgesic administration and incidence of vomiting. In summary, alfentanil (12.5-50.0 μg · kg-1) was a safe anaesthetic, whether combined with nitrous oxide alone or with nitrous oxide and halothane. © 1991 Canadian Anesthesiologists.