Nitrous oxide administration during washout of sevoflurane improves postanesthetic agitation in children

Abstract

The use of sevoflurane in pediatric patients, which could enable a more rapid emergence and recovery, is complicated by a high incidence of postanesthetic agitation, probably due to residual sevoflurane during washout. The present study was designed to investigate whether administration of nitrous oxide (N₂O) reduces sevoflurane concentration at awakening and suppresses postanesthetic agitation. The study enrolled 20 children classified as ASA physical status I. Anesthesia was induced with 5% sevoflurane and maintained with 2.5% end-tidal sevoflurane and N₂O in oxygen. In the control group, sevoflurane and N₂O were discontinued immediately after completion of surgery. In the N₂O group, inspired N₂O was replaced with oxygen after the bispectral index (BIS) had reached 80. The end-tidal concentrations of sevoflurane at awakening were significantly lower (P < 0.05) in the N₂O group than in the control group. The BIS at awakening was higher (P < 0.01) in the N₂O group than in the control group. The point scores of postanesthetic agitation were significantly lower (P < 0.01) in the N₂O group than in the control group. Using N₂O during washing out of sevoflurane may improve postanesthetic agitation at awakening in children.