Anesthésiques halogénés

Among the five halogenated agents used in France, halothane and enflurane are now less administered than the more recent isoflurane, desflurane and sevoflurane, especially owing to the pharmacokinetic and cardiovascular advantages of these three agents. In terms of clinical effects, their differences are slight and, despite recent controversies on sevoflurane renal effects, all three are now considered as devoid of toxicity. The main relevant difference between sevoflurane or desflurane and isoflurane is their faster pharmacokinetics with subsequent differences in the rapidity of induction and awakening. However such difference reaches only few minutes, which is not relevant enough to shorten the stay in the recovery room. Besides, the cost of anaesthesia is 4-fold increased with desflurane and isoflurane. Both should be preferentially used in closed circuit, with the fresh gas flow as reduced as possible. Whatever their cost and the way they are used, halogenated agents are far less expensive than intravenous agents. Moreover, their duration of action is shorter despite an increased incidence of postoperative nausea and vomiting. Because sevoflurane has little pungency, mask induction with sevoflurane in children and adult is now an alternative to intravenous induction but the consequences of several adverse effects such as tachycardia and epileptic-like brain activity deserve to be better evaluated.