End-tidal desflurane concentration for tracheal extubation in adults

Abstract

Abstract Objective To determine the end-tidal desflurane concentration required for tracheal extubation in anaesthetised adults. Material and methods After hospital Ethics Committee approval, eighteen ASA I–II adult patients (19–65 years of age), who had been scheduled for elective ambulatory surgery were included in the study. Anaesthesia was induced with propofol 2.5 mg / kg, fentanyl 2 μg/kg, and rocuronium 0.6 mg/kg for intubation. Maintenance of anaesthesia was provided by desflurane in oxygen and air (40:60), and remifentanil at 0.05–0.25 μg/kg/min. Neuromuscular function was monitored with train-of-four (TOF) nerve stimulation and acceleromyography. At the end of the surgery neuromuscular blockade was reversed with sugammadex 2–4 mg/kg in accordance with the TOF ratio. The concentration of desflurane at which extubation was attempted was determined by using Dixon's up-and-down method with 0.5% as a step size. Smooth extubation was defined as one without coughing, teeth clenching, gross purposeful movements, and no breath-holding or laryngospasm within 1 min of tracheal extubation. Results It was found that the end-tidal concentration of desflurane was 3.17 ± 0.18% (95% CI: 3–3.35%) for successful extubation in 50% of adults. Conclusion Extubation in patients receiving desflurane may be feasible at 0.62 minimum alveolar concentration.