Cognitive impairment in the early postoperative period after remifentanil/propofol or sevoflurane/fentanyl anaesthesia

Objective: In ambulatory anaesthesia the time required to recover from cognitive impairment should be as short as possible. The aim of this study was to compare the early cognitive recovery after remifentanil/propofol (R/P) and sevoflurane/fentanyl (S/F) anaesthesia. Methods: Sixty patients scheduled for elective gynaecological laparoscopy and 24 female volunteers tested for the assessment of learning effects were investigated. After praemedication with midazolam anaesthesis was induced with propofol, atracurium and either 1 mu g/kg fentanyl or 1 mu g/kg remifentanil. For maintenance 0.25 mu g/kg/min remifentanil and 0.6 mg/kg/min propofol (R/P) or 1.7 vol% sevoflurane (S/F) were given. Both groups were ventilated with 30% oxygen in air and received metamizol for postoperative analgesia. Verbal Learning Test, Stroop Colour and Word Interference Test, Digit Symbol Substitution Test and Four Boxes Test were performed the day before surgery and 30 min, 1 h, 2 h and 4 h after termination of anaesthesia. Results: For remifentanil/propofol cognitive function was still impaired 2 h (Verbal Learning) and 4 h (Stroop, Digit Symbol Substitution and Four Boxes Test) after termination of anaesthesia. After sevoflurane/fentanyl anaesthesia cognitive impairment lasted the same duration in Four Boxes Test, but shorter in Stroop and Digit Symbol Substitution and could not be found in Verbal Learning Test. Conclusion:The duration of cognitive impairment in the early postoperative period differed by the test procedures and the anaesthetic procedures used in this investigation. Recovery appeared to be faster after sevoflurane/fentanyl than after remifentanil/propofol at least in aspects of cognitive function.