硬膜外小剂量氯胺酮在不同给药时间的超前镇痛效果

The Efficacy of Preemptive Analgesia of Small Doses of Epidural Ketamine at Different Administration Time

目的观察硬膜外小剂量氯胺酮在不同给药时间的超前镇痛效果。方法60例行剖宫产术的病人随机分为3组,每组20例。分别在切皮前(A组)、手术后(B组)硬膜外注入氯胺酮30mg,切皮前硬膜外注入生理盐水1ml(C组),术后均采用硬膜外病人自控镇痛(PCEA)。观察术中平均动脉压(MAP)、心率(HR)、SpO2、新生儿Apgar评分,术后感觉疼痛时间、镇痛药用量、术后VAS评分和副作用。结果3组病人术中BP、HR、SpO2及新生儿Apgar评分皆无显著性差异(P>0.05)。术后疼痛开始时间,与C组比较,A组和B组均明显延长(P<0.01),A组和B组之间无显著性差异(P>0.05)。PCEA术后用药量依次为C组>B组>A组,3组间均有显著性差异(P<0.05)。患者术后排气时间及PCEA的VAS评分3组间无显著性差异(P>0.05)。与C组比较,A组和B组副作用发生率均显著降低(P<0.05),A组和B组之间无显著性差异(P>0.05)。结论硬膜外小剂量氯胺酮能降低术后病人PCEA时镇痛药的需要量,尤其切皮前用药更能有效地发挥超前镇痛作用。

Objective To observe the efficacy of preemptive analgesia of small doses of epidural injection with ketamine at different administration time.Methods Sixty patients undergoing cesarean section were randomly divided into 3 groups( n =20).Ketamine 30mg(group A) or saline 1ml(group C) was given by epidural injection before skin incision, or ketamine 30mg(group B) was injected postoperatively. MAP,HR,SpO_2,neonatal Apgar Scores in operation ,postoperative time of aching, the postoperative required analgesic dosage, incidences of side-effect and VAS score of PCEA were observed. Results The MAP,HR,SpO_2 and neonatal Apgar Scores in operation among three groups were no difference( P >0.05).The postoperative time of aching was significantly longer in group A and B than that in C( P <0.01),but not difference between the group A and B( P >0.05).The postoperative required analgesic dosage was obviously smaller in group A and B than that in C, but there was a significant increase in group B in comparison with A( P <0.05). The VAS scores of three groups were similar .The rates of nausea and vomiting were higher in group C than those in group A and B( P <0.05).Conclusion Small dose of epidural injection of ketamine can decrease the required analgesic dosage after operation.Epidural ketamine given before skin incision can produce preemptive analgesia more effectively than given postoperatively.