Introduction: The application of a “Fast-track” anaesthetic protocol has been common . Impaired postoperative cognitive function has been related to many factors . However, no optimal anaesthetic regime has been determined for both a “Fast-track” protocol and for cognitive function preservation.
Method: After ethical committee approval, 40 ASA II-III patients were randomly included in the study. Anaesthesia was induced with 0.1 mg kg−1 midazolam, 1 μg kg−1 propofol and 0.1 mg kg−1 vecuronium in all patients. In addition 1 μg kg−1 remifentanil iv. was given to the patients in Group I (n 20) and remifentanil infusion at a rate of 0.25-0.5 μg kg−1 min−1 was given throughout the operation. 5 μg kg−1 fentanyl iv. was given to the patients in Group II (n 20) and 3 μg kg−1 h−1 was infused throughout the operation. Anaesthesia was maintained by propofol 2 mg kg−1 h−1 and 0.2-0.5% isoflurane. 50% O2 in air was given to all patients before and after CPB. Under 30-32°C hypothermic CBP, propofol infusion rate was reduced to 1 mg kg−1 h−1.
Pulmonary capillary wedge pressure (PCWP), mean pulmonary artery pressure (MPAP), mean arterial pressure (MAP) and heart rate (HR) were recorded at 12 different periods. In addition, intra-operative and postoperative cardiac output (CO) and cardiac index (CI), extubation times (ET) and onset times of spontaneous breathing (OTSB) of all patients were measured.
Cognitive functions were evaluated according to a standard neuropsychiatric test scale consisting of 9 different tests, preoperatively and 5 days postoperatively.
Results: Haemodynamic parameters are shown in Table 1.
ET and OTSB were shorter in Group II than Group I (P < 0.05). Cognitive function tests of both groups were defective at the 5th postoperative day compared with the preoperative period (P < 0.01).
Conclusion: Haemodynamic stability was established with fentanyl and remifentanil in patients undergoing CABG surgery. However, remifentanil was superior to fentanyl because of shorter ET and OTSB. Neither remifentanil nor fentanyl was superior in preservation of cognitive function.
1 Engoren M, Luther G, Fenn-Buderer N. A comparison of fentanyl, sufentanil and remifentanil for fast-track cardiac anesthesia. Anesth Analg
2 Shaw PJ, Bates D, Cartlidge NE, et al. Long term intellectual dysfunction following coronary artery bypass graft surgery: a six month follow-up study. Q J Medicine