Research of the optimal dose of butorphanol to prevent emergence agitation after general anesthesia in pediatrics

Objective To compare the effect and safety of different dose of butorphanol intravenous injection and discuss the optimal dose of butorphanol to prevent emergence agitation after general anesthesia in pediatrics.Methods 120 cases (6-12 years old,ASA Ⅰ-Ⅱ) were selected from patients who scheduled for laparoscopic surgery under sevoflurane general anesthesia.With a completely randomized and double blind method,they were divided into 4 groups:butorphanol 10 μ g/kg group (group B1),butorphanol 20 μ g/ kg group (group B2),butorphanol 30 μ g/kg group (group B3) and placebo group (group C).Group B1-B3 received corresponding dose of butorphanol 10 minutes before operation was over,while group C received the same volume of saline.Monitored HR,MAP,RR and SPO2 before operation (T0),at the time entering PACU (T1),5,10,15,20 minutes after entering PACU (T2-T5) and at the time going out of PACU (T6).Recorded tracheal extubation time,recovery time,residence time of PACU and PAED.Recorded Ramsey sedation score 2,4 and 8 hours after operation and adverse reactions.Results MAP,HR at T1-T6 in group B1 were significantly lower than those in group C (P ＜ 0.05); MAP,HR at T1-T5 in group B2 and B3 were significantly lower than those in group C (P ＜ 0.01).In group B3,MAP,HR at T1-T3 decreased significantly compared with those at T0 (P ＜ 0.05).The incidence of moderate and severe emergence agitation in group B1 was lower than that in group C (P ＜ 0.05),the incidences of moderate and severe emergence agitation in group B2 and B3 were significantly lower than that in group C (P ＜ 0.01).Recovery time and residence time of PACU in group B3 were significantly longer than those in other 3 groups (P ＜ 0.05).Ramsay scores of 2,4 hours after operation in group B3 were higher than those in group B1 and B2 (P ＜ 0.05),which were significantly higher than those in group C (P ＜ 0.01).The incidence of lethargy in group B3 was higher than that in other 3 groups (P ＜ 0.05).Conclusion The dose of 20 μ g/kg butorphanol has good effect in preventing emergence agitation,which can avoid excessive sedation as well. Key words: Butorphanol;  Pediatric patient;  Emergence agitation;  Optimal dose