Background: Postoperative cognitive dysfunction (POCD) is being recognized as a complication contributing to perioperative morbidity and mortality of the elderly. We hypothesized that the use of the shorter-acting volatile anaesthetic desflurane would be associated with less incidence of POCD when compared with sevoflurane.
Methods: Approved by the local ethical committee, 80 patients (aged 65-75 yr) were enrolled in this randomized, double-blinded study. Patients were allocated to either the desflurane (n=40) or the sevoflurane (n=40) group. The primary outcome was the cognitive Test for Attentional Performance with its subtests Alertness, Divided Attention, Visual Scanning, Working Memory, and Reaction Change. In addition, Paper-Pencil Tests [Well-being Test BF-S, Recall of Digit Span (DST), Digit-Symbol-Substitution Test, Trail Making Tests A and B, and Spielberg State-Trait Anxiety Inventory] were measured. After baseline assessment 12-24 h before operation, patients were followed up 6-8 and 66-72 h after operation. Among other outcome parameters, emergence times from anaesthesia and modified Aldrete scores were recorded.
Results: There was no difference in the incidence of POCD. However, according to the Paper-Pencil Tests, significant improvements for the desflurane group could be detected (Well-being Test at 6-8 h, DST at 6-8 h, and Trail Making Test at 66-72 h). Emergence was significantly faster in the desflurane group for 'time to open eyes' and 'time to extubation'.
Conclusions: The total incidence of POCD showed no differences between the desflurane and the sevoflurane groups. However, the tests Well-being scale, DST, and Trail Making Test, emergence times, and patients' satisfaction were in favour of desflurane.