An open, randomized comparison of alfentanil, remifentanil and alfentanil followed by remifentanil in anaesthesia for craniotomy

We studied 52 adults undergoing elective craniotomy, allocated randomly to one of three opioid treatments: alfentanil 50 mu g kg(-1) followed by 0.833 mu g kg(-1) min(-1) until dural closure (group Alf.); alfentanil 50 mu g kg(-1) followed by 0.833 mu g kg(-1) min(-1) for 2 h, then remifentanil 0.25 mu g kg(-1) min(-1) (group Alf.-Remi.); or remifentanil 1 mu g kg(-1) followed by 0.5 mu g kg(-1) min(-1) reducing to 0.25 mu g kg(-1) min(-1) after craniotomy (group Remi.). Anaesthesia was maintained with infusion of propofol and 66% nitrous oxide in oxygen. Infusions of propofol and remifentanil were stopped at head bandaging. Group Remi. had the least intraoperative haemodynamic responses and group Alf. the most (P<0.05). Times to tracheal extubation and obey commands were similar in all groups. In all patients in group Alf.-Remi. and group Remi., the trachea was extubated 27 min from the end of anaesthesia; three patients in group Alf. were slower to recover. Use of analgesia in the recovery room and time to transfer to the neurosurgical unit were similar in the three groups.