A Comparison of Remifentanil and Alfentanil Infusions in Abdominal Surgery

Objective: We studied the efficacy and safety of remifentanil and alfentanil infusions in combination,with inhalational anesthesia during abdominal surgery. Material and methods: Forty patients, ASA I-II aged between 22-65 years were randomly allocated into two groups. Anesthesia was induced with remifentanil 1 mu g/kg bolus, followed by 0.5 mu g/kg/Min infusion in the remifentanil group (Group R, n=20), alfentanil 25 mu g/kg bolus and 1 mu g/kg/min infusion in the alfentanil group (Group A. n=20) and propofol was given at a rate of 10 mg/10 sec until loss of consciousness. Lungs were ventilated with 0.5% end-tidal isoflurane and 66% N,O-2/O-2,. Infusion rates were reduced by 50% 5 minutes after intubation. Remifentanil was discontinued at the end of operation and alfentanil 15 minutes before. Autonomic and somatic responses to surgery were controlled with bolus and infusion rate increases. Recovery was assessed with the time for spontaneous and adequate respiration, response to verbal command and Aldrete scores. Results: Hemodynamic response to surgery, drug boluses and increases in infusion rates were found to be higher in Group A, while incidences of hypotension and bradycardia were higher in Group R. In Group R, adequate respiration, extubation and response to verbal command were shorter and Aldrete scores were similar. Conclusion: Remifentanil, when administered at the same doses with this study, controlled intraoperative hemodynamic response better in comparison with alfentanil and was found to be more effective and safe because fits rapid recovery properties.