Delayed recovery of cognitive function is a well-recognized phenomenon in older patients. The potential for the volatile anaesthetic used to contribute to alterations in postoperative cognitive function in older patients following minor surgical procedures has not been determined. We compared emergence from isoflurane and sevoflurane anaesthesia in older surgical patients undergoing urological procedures of short duration.

Seventy-one patients, 60 yr of age or older, undergoing anaesthesia expected to last less than 60 min for ambulatory surgery, were randomly assigned to receive isoflurane or sevoflurane. A standardized anaesthetic protocol was used, with intravenous fentanyl 1 μg kg−1 and propofol 1.5–2.0 mg kg−1 administered to induce anaesthesia. Anaesthesia was maintained with either sevoflurane or isoflurane in 65% nitrous oxide and oxygen. Early and intermediate recovery times were recorded. The mini mental state examination and digit repetition forwards and backwards were administered at baseline, and at 1, 3 and 6 h postoperatively, to assess cognitive function.

There were no between-group differences in (sevoflurane vs. isoflurane, mean ± standard error of the mean) times to removal of the laryngeal mask airway (7.7 ± 0.6 vs. 7.1 ± 0.4 min), verbal response time (10.1 ± 0.7 vs. 9.9 ± 0.7 min) and orientation (12.1 ± 0.7 vs. 12.1 ± 0.7 min). Intermediate recovery, as measured by time to readiness for discharge from the post anaesthesia care unit (44.9 ± 1.5 vs. 44.3 ± 1.5 min), was similar in the two groups. Postoperative indices of cognitive function and attention were comparably reduced at 1 h, but returned to baseline in both groups at 6 h.

Isoflurane and sevoflurane anaesthesia resulted in similar clinical and neurocognitive recovery profiles in older patients undergoing ambulatory surgical procedures of short duration.

Early recovery after anaesthesia is gaining importance in fast track management. The aim of this study was to quantify psychomotor recovery within the first 24 h after propofol/remifentanil anaesthesia using the Short Performance Test (Syndrom Kurztest (SKT)), consisting of nine subtests. The hypothesis was that psychomotor performance remains reduced 24 h after anaesthesia.

Thirty-seven patients scheduled for elective surgery took part in the study. The SKT was performed on the day before general anaesthesia (T0), 10, 30, 90 min and 24 h after extubation (T1). Parallel versions were used to minimize learning effects. Anaesthesia was introduced and maintained with remifentanil/propofol as a target controlled infusion. Propofol plasma concentration was measured 10 and 90 min after extubation. Perioperative pain management included novaminsulfon and piritramide.

Up till 90 min after surgery and anaesthesia, psychomotor performances were significantly reduced as the lower test results in all SKT subtests indicated (P ⩽ 0.007 vs. baseline T0). In the three memory subtests (ST 2, ST 8 and ST 9), psychomotor performance was still reduced on the first postoperative day (P ⩽ 0.005; T1 vs. T0). There was no correlation between propofol plasma concentration and the psychometric test results.

Propofol/remifentanil-based target controlled general anaesthesia for surgery is associated with a reduced psychomotor function up to the first postoperative day. Further studies are needed to confirm the usefulness of the SKT in the perioperative period and to clarify which components in the perioperative period are responsible for a lower performance in the SKT.