The main advantage of sevoflurane over halothane is its remarkable cardiovascular safety.
The cardiovascular effects of sevoflurane are similar to those of isoflurane.
It does not sensitize the myocardium to exogenous or endogenous catecholamines, and
thus promotes less arrhythmias than halothane especially during ENT surgery, dental surgery or endoscopies.
Sevoflurane does not modify atrio-ventricular conduction time. Therefore, the incidence of bradycardia is much lower with sevoflurane than with halothane, especially in infants.
Sevoflurane depresses myocardial contractility to a lesser extent than halothane does in infants and children . The latter is of greatest importance during induction especially in children with compromised cardiovascular function.
Sevoflurane, as well as halothane and isoflurane, markedly depresses baroreflex control of heart rate in infants and children .
On recovery, baroreflex control of heart rate is more rapidly restored after sevoflurane anaesthesia than after isoflurane anaesthesia reflecting the more rapid elimination of sevoflurane compared to isoflurane in adult patients .
This very safe cardiovascular profile of sevoflurane has changed the practice of face-mask induction in children. With halothane, a stepwise incremental induction technique was recommended in order to limit the cardiovascular depression, and close monitoring of heart rate and heart sounds was mandatory. Soon after sevoflurane was introduced into clinical practice, it became evident that high concentrations of sevoflurane were well tolerated allowing for rapid induction with very few respiratory and cardiovascular side-effects.
When using 7 or 8% sevoflurane, loss of consciousness is achieved in about 40 to 45 s, and tracheal intubation can be performed without addition of neuromuscular blocking agents in less than 5 min in most patients .
Wodey E, Pladys P, Copin C, Lucas M, Chaumont A, Carre P, Lelong B, Azzis O, Ecoffey C: Comparative hemodynamic depression of sevoflurane versus halothane in infants. Anesthesiology 1997; 87: 795-800
Russell IA, Miller Hance WC, Gregory G, Balea MC, Cassorla L, DeSilva A, Hickey RF, Reynolds LM, Rouine- Rapp K, Hanley FL, Reddy VM, Cahalan MK: The safety and efficacy of sevoflurane anaesthesia in infants and children with congenital heart disease. Anaesthesia Analgesia 2001; 92: 1152-8
Dubois MC, Piat V, Constant I, Lamblin O, Murat I: Comparison of three techniques for induction of anaesthesia with sevoflurane in children. Paediatr Anaesth 1999; 9: 19-23
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