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Volatile anesthetic agent use in the intensive care unit, aided by technological advances, has become more accessible to critical care physicians. With increasing concern over adverse patient consequences associated with our current sedation practice, there is growing interest to find non-benzodiazepine-based alternative sedatives. Research has demonstrated that volatile-based sedation may provide superior awakening and extubation times in comparison with current intravenous sedation agents (propofol and benzodiazepines). Volatile agents may possess important end-organ protective properties mediated via cytoprotective and antiinflammatory mechanisms. However, like all sedatives, volatile agents are capable of deeply sedating patients, which can have respiratory depressant effects and reduce patient mobility. This review seeks to critically appraise current volatile use in critical care medicine including current research, technical consideration of their use, contraindications, areas of controversy, and proposed future research topics.

Background: There is a concern that obesity may play a role in prolonging emergence from fat-soluble inhalational anaesthetics. We hypothesized that increased pulmonary clearance of isoflurane will shorten immediate recovery from anaesthesia and post-anaesthesia care unit (PACU) stay in obese patients., Methods: After Ethics Review Board approval, 44 ASA I-III patients with BMI>30 kg/m(2) undergoing elective gynaecological or urological surgery were randomized after completion of surgery to either an isocapnic hyperpnoea (IH) or a conventional recovery (C) group. The anaesthesia protocol included propofol, fentanyl, morphine, rocuronium and isoflurane in air/O(2) . Groups were compared using unpaired t-test and ANOVA., Results: Minute ventilation in the IH group before extubation was 22.6 ± 2.7 vs. 6.3 ± 1.8 l/min in the C group. Compared with C, the IH group had a shorter time to extubation (5.4 ± 2.7 vs. 15.8 ± 2.7 min, P<0.01), initiation of spontaneous ventilation (2.7 ± 2.3 vs. 6.5 ± 4.5 min, P<0.01), BIS recovery >75 (3.2 ± 2.3 vs. 8.9 ± 5.8 min, P<0.01), eye opening (4.6 ± 2.9 vs. 13.6 ± 7.1 min, P<0.01) and eligibility for leaving the operating room (7.1 ± 2.9 vs. 19.9 ± 11.9 min, P<0.01). There was no difference in time for eligibility for PACU discharge., Conclusion: Increasing alveolar ventilation enhances anaesthetic elimination and accelerates short-term recovery in obese patients., (© 2011 The Authors. Acta Anaesthesiologica Scandinavica © 2011 The Acta Anaesthesiologica Scandinavica Foundation.)