骶管阻滞对小儿七氟烷最低肺泡清醒浓度的影响

The Influence on MAC-awake of Sevoflurane by Sacral Block in Children

目的探讨骶管阻滞对小儿七氟烷最低肺泡清醒浓度(MAC-awake)的影响。方法选择60例(2～8岁)择期行泌尿外科手术患儿,随机分为2组:Ⅰ组(单纯吸入全麻组)和Ⅱ组(骶管阻滞复合全麻组),每组30例。患儿麻醉前30min肌肉注射阿托品0.01mg/kg,Ⅱ组经骶管裂孔给予0.25%罗哌卡因1ml/kg,两组麻醉诱导和术中维持均用七氟烷且均不行气管插管,保留自主呼吸,手术结束时维持呼气末七氟烷目标浓度10min,根据序贯法记录患儿清醒睁眼睛时呼气末七氟烷浓度,通过probit检验计算两组的MAC-awake值(ED50)。结果Ⅱ组七氟烷MAC-awake(0.39%)明显低于Ⅰ组(0.62%),2组之间差异有统计学意义(P<0.01)。结论骶管阻滞能降低小儿七氟烷最低肺泡清醒浓度。

Objective To investigate the influence on MAC-awake of sevoflurane by sacral block in children. Methods 60 patients(2～8 years old)undergoing urogenital surgery were randomly allocated to receive general anesthesia group (groupⅠ,n =30)or combined generalsacral block anesthesia group(groupⅡ,n =30).The patients were premedicated with intramuscular atropine 0.01 mg/kg 30 min before anesthesia . In groupⅡ,we used inhalation combined with sacral block(0.25% Ropivacaine 1 ml/kg). All patients keep respiration without intubation. Anesthesia was maintained with sevoflurane,at the end of surgery,a predetermined end-tidal sevoflurane concentration was maintained for at least 10 min before a standard stimulus was applied and an observer determined if the child was awake. The Dixon up-down method was used to determine the progression of subsequent concentration,the MAC-awake(ED50)for the two groups were obtained using the probit model. Results This study found evidence for a difference in MAC-awake between the two groups,the MAC-awake of sevoflurane in group Ⅱ(0.39%)was less than that in group Ⅰ(0.62%)(P < 0.01). Conclusion The MAC-awake of sevoflurane can be reduced by sacral block in children.