Background and aim We investigated the haemody-namic stability and emergence characteristics of isoflur-ane/nitrous oxide anaesthesia supplemented with remifentanil or fentanyl in patients undergoing carotid endarterectomy.

Methods Anaesthesia was induced with propofol (1–2mgkg−1) and either remifentanil (O.5μgkg−1) or fentanyl (1 μgkg−1), followed by an infusion of remifentanil (0.2 μg kg−1 min−1) or fentanyl (2 μg kg−1 h−1).

Results There were no significant differences between the groups in haemodynamic variables, postoperative pain, nausea or vomiting. After induction there was a significant decrease in mean arterial pressure for both groups (P<0.001) and a decrease in heart rate (P=0.001) in the remifentanil group. In both groups these haemodynamic changes continued during maintenance of anaesthesia (P<0.05). The time to eye opening after surgery was significantly shorter with remifentanil compared with fentanyl (6.62±3.89 vs. 18.0±15.18min, P=0.015).

Conclusion Remifentanil appears to be a comparable opioid to fentanyl when supplementing isoflurane/nitrous oxide anaesthesia for carotid endarterectomy.