Postoperative nausea nitrous oxide

Visser K, Hassink EA, Bonsel GJ, Moen J, Kalkman CJ. Randomized controlled trial of total intravenous anesthesia with propofol versus inhalation anesthesia with iso-flurane-nitrous oxide postoperative nausea with vomiting and economic analysis. Anesthesiology 2001 95(3) 616-26. 

Nitrous oxide is associated with postoperative nausea and vomiting. This probably involves both central and peripheral mechanisms, the latter is the result of distension of the gut due to rapid movement of nitrous oxide into the lumen. It is possible that better operating conditions are achieved when nitrous oxide is avoided. 

The chemical structures of the currently available inhaled anesthetics are shown in Figure 25-2. The most commonly used inhaled anesthetics are isoflurane, desflurane, and sevoflurane. These compounds are volatile liquids that are aerosolized in specialized vaporizer delivery systems. Nitrous oxide, a gas at ambient temperature and pressure, continues to be an important adjuvant to the volatile agents. However, concerns about environmental pollution and its ability to increase the incidence of postoperative nausea and vomiting (PONV) have resulted in a significant decrease in its use. 

Leslie K, Myles PS, Chan MT, Paech MJ, Peyton P, Forbes A, McKenzie D. ENIGMA Trial Group. Risk factors for severe postoperative nausea and vomiting in a randomized trial of nitrous oxide-based vs. nitrous oxide-free anaesthesia. Br J Anaesth 2008 101(4) 498-505. 

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