[Sevoflurane in pediatric anesthesia]

Sevoflurane may be an interesting substance for paediatric anaesthesia due to its combination of a very low blood-gas partition coefficient and non-pungency. This review discusses the status of sevoflurane in paediatric anaesthesia on the basis of studies published so far. The blood-gas partition coefficient of sevoflurane in children is 0.66, and hence markedly lower than those of isoflurane (1.25) and halothane (2.26) [15]. Induction of anaesthesia with sevoflurane/N2O is slightly shorter compared to halothane/N2O (Table 1) [4]. During induction of anaesthesia, sevoflurane/O2 is more often associated with excitement (35%) than sevoflurane/N2O (5%) and halothane/N2O (5%) [25]. Seizure-like movements in one case [1] and electrically generalised but clinically silent seizure activity in two cases [12] may raise the question of seizure-inducing effects of sevoflurane. However, up to now there is no clinical evidence of epileptogenic effects of sevoflurane. The MAC50 in neonates and infants 1-6 months of age is 3.3 vol% [14]; in infants 6-12 months and children 1-12 years of age it is 2.5 vol.% [14]. Sixty per cent N2O decreases the MAC50 of sevoflurane and desflurane by only 20%-25% [3, 14]. In contrast, 60% N2O decreases the MAC50 of halothane in children by 60% [16]. Thus, the MAC-reducing effect of N2O in children appears to be attenuated in the presence of less soluble inhalation anaesthetics. Sevoflurane has a similar low incidence of airway irritation as halothane and provides a smooth induction (Fig. 2) [4]. Haemodynamics during sevoflurane anaesthesia may be somewhat more stable compared to halothane. Serum fluoride levels increase rapidly when sevoflurane is administered, but decrease shortly after discontinuation [4]. Mean maximum levels reported are about 20 mumol/l and are of no concern for renal function. A study with mivacurium indicates more pronounced muscle relaxation by sevoflurane compared to halothane [9]. Sevoflurane may induce malignant hyperthermia. Emergence from sevoflurane anaesthesia is significantly more rapid than after halothane anaesthesia (Table 1); however, it is associated with more restlessness and agitation, probably due to the earlier perception of pain [4]. The incidence of postoperative nausea and vomiting after sevoflurane anaesthesia is comparable to that after halothane (Table 2). Sevoflurane may be a user-friendly alternative to halothane and is more preferred by children than halothane [32]. The status of sevoflurane in paediatric anaesthesia will depend on several factors: its own benefit/risk-ratio, a possible re-evaluation of the known risks of halothane and the financial limitations of the hospitals.