EMERGENCE FROM ANESTHESIA AND RECOVERY OF COGNITIVE FUNCTIONS AFTER DESFLURANE OR ISOFLURANE

Desflurane is a new volatile anaesthetic with an extremely low blood/g as partition coefficient of 0.42, This should provide a rapid recovery from anaesthesia. Methods, We studied 100 adult patients, ASA class I or II, undergoing elective orthopaedic surgery randomly assigned to a naesthesia with desflurane (n = 50) or isoflurane (n = 50) supplemente d by nitrous oxide in oxygen, Clorazepat was given for premedication, fentanyl and thiopental for induction of anaesthesia, followed by main tenance with desflurane or isoflurane as clinically appropriate, Emerg ence from anaesthesia was measured as well as return of cognitive func tions (extended Aldrete score, digit symbol substitution test, and vis ual analogue scales [VAS]). Results. While the characteristics and dos es of fentanyl and thiopental were comparable, the recovery profiles i n both groups were different, After discontinuation of the volatile an aesthetics, times to extubation and ability to follow simple commands were significantly shorter after desflurane than after isoflurane, Ext ended Aldrete scores, estimation of the patients' physical condition, results of the digit symbol substitution test, measuring cognitive fun ctions, and rates of drowsiness and weakness on VAS showed better reco very with less impairment of cognitive function in the desflurane grou p than in isoflurane patients even 120 min after anaesthesia. VAS pain scores and doses of analgesic drugs given within the first 2 postoper ative hours, however, showed no significant differences, Desflurane pa tients were also judged fit for discharge from the recovery room signi ficantly faster, Conclusions, Our results demonstrate that desflurane anaesthesia, even when supplemented by premedication, intraoperative o pioids, and nitrous oxide may offer clinical advantages over isofluran e as far as the post-anaesthetic recovery profile is concerned.