RESUMO
BACKGROUND: We hypothesized that emergence from sedation in postoperative patients in the intensive care unit would be faster and more predictable after sedation with desflurane than with propofol. METHODS: Sixty patients after major operations were allocated randomly to receive either desflurane or propofol. The target level of sedation was defined by a bispectral index(TM) (BIS(TM)) of 60. All patients were receiving mechanical ventilation of the lungs for 10.6 (SD 5.5) h depending on their clinical state. The study drugs were stopped abruptly in a calm atmosphere with the fresh gas flow set to 6 litres min(-1), and the time until the BIS increased above 75 was measured (t(BIS75), the main objective measure). After extubation of the trachea, when the patients could state their birth date, they were asked to memorize five words. RESULTS: Emergence times were shorter (P<0.001) after desflurane than after propofol (25th, 50th and 75th percentiles): t(BIS75), 3.0, 4.5 and 5.8 vs 5.2, 7.7 and 10.3 min; time to first response, 3.7, 5.0 and 5.7 vs 6.9, 8.6 and 10.7 min; time to eyes open, 4.7, 5.7 and 8.0 vs 7.3, 10.5 and 20.8 min; time to squeeze hand, 5.1, 6.5 and 10.2 vs 9.2, 11.1 and 21.1 min; time to tracheal extubation, 5.8, 7.7 and 10.0 vs 9.7, 13.5 and 18.9 min; time to saying their birth date, 7.7, 10.5 and 15.5 vs 13.0, 19.4 and 31.8 min. Patients who received desflurane recalled significantly more of the five words. We did not observe major side-effects and there were no haemodynamic or laboratory changes except for a more marked increase in systolic blood pressure after stopping desflurane. Using a low fresh gas flow (air/oxygen 1 litre min(-1)), pure drug costs were lower for desflurane than for propofol (95 vs 171 Euros day(-1)). CONCLUSIONS: We found shorter and more predictable emergence times and quicker mental recovery after short-term postoperative sedation with desflurane compared with propofol. Desflurane allows precise timing of extubation, shortening the time during which the patient needs very close attention.