静脉泵注右美托咪定对剖宫产术后吗啡硬膜外镇痛效果的影响

Effects of patient controlled intravenous analgesia with dexmedetomidine for epidural analgesia with morphine after cesarean section

目的观察静脉泵注右美托咪定(dexmedetomidine,Dex)对剖宫产术后吗啡硬膜外镇痛效果的影响。方法本研究为随机、双盲、安慰剂对照的初步研究。选择20~40岁,择期于蛛网膜下腔-硬膜外麻醉下行剖宫产术的产妇80例,采用随机数字表法分为Dex+吗啡组(A组)和吗啡组(B组),每组40例。两组产妇均于术毕硬膜外给予吗啡2.5mg一次性镇痛,A组在胎儿取出后给予负荷量Dex0.5μg/kg持续静脉滴注15min,术毕接一次性患者自控镇痛(patient controlled analgesia,PCA)泵以0.1μg·kg^-1·h^-1持续泵注;B组均给予等量生理盐水输注。观察并记录产妇术后4h(T1)、术后8h(T2)、术后12h(T3)、术后24h(T4)的VAS评分、警觉/镇静评分(Observers Assessment of Alertness/Sedation Scale,OAA/S),麻醉前、术毕、T4时的血清肾素、皮质醇、K+浓度,镇痛期间不良反应发生情况,术中及T4时尿量。结果A组术毕、T4时血清皮质醇浓度低于B组[(0.32±0.08)mg/L比(0.36±0.08)mg/L,(0.20±0.07)mg/L比(0.24±0.08)mg/L,P<0.05]。A组术毕血清肾素浓度低于B组[(30±11)ng/L比(36±13)ng/L,P<0.05]。两组血清K+浓度比较,差异无统计学意义(P>0.05)。A组T3、T4时VAS评分低于B组[(2.0±0.7)分比(2.3±0.6)分,(2.1±0.6)分比(2.4±0.7)分,P<0.05]。A组镇痛期间发生寒战、恶心呕吐的例数低于B组(0例比6例,1例比7例,P<0.05)。结论Dex静脉泵注复合吗啡硬膜外镇痛用于剖宫产术后镇痛能降低产妇应激反应,不良反应少,镇痛效果满意,效果优于单独使用吗啡。

Objective To investigate the effect of dexmedetomidine (Dex) on epidural analgesia with morphine after cesarean section. Methods This is a preliminary study by a randomized, double-blind and placebo-controlled method. Eighty puerperants between 20-40 years old scheduled for cesarean section by combined spinal-epidural analgesia were randomly divided into Dex+morphine group (group A) and morphine group (group B)(n=40). Puerperants in two groups were given a single epidural injection of morphine 2.5 mg. Puerperants in group A were given continuous intravenous drip of Dex for 15 min at the dose of 0.5 μg/kg after the fetuses were taken out, then postoperative patient-controlled analgesia(PCA) at the dose of 0.1 μg·kg^-1·h^-1 was used. Puerperants in group B were given equal doses of physiological saline. Cortisol, renin and potassium ion concentrations in serum at the time of before anesthesia, after the operation and 24 h (T4) after the operation. Visual Analogue Scale (VAS), Observers Assessment of Alertness/Sedation Scale (OAA/S) and adverse effects during the anesthesia [4 h (T1), 8 h (T2), 12 h (T3), T4 after the operation] were observed and recorded. The urine volume(during the operation and T4) were observed and recorded. Results At the end of operation and T4, the averaged cortisol concentration of the puerperants in group A was lower than the concentration of patients in group B [(0.32±0.08) mg/L vs(0.36±0.08) mg/L,(0.20±0.07) mg/L vs(0.24±0.08) mg/L, P<0.05]. At the end of the operation, the averaged renin concentration of group A was lower than the concentration of group B [(30±11) ng/L vs(36±13) ng/L, P<0.05]. The potassium ion concentration was not statistically different between two groups (P>0.05). At T3, T4, the VAS of group A was lower than group B [(2.0±0.7) vs (2.3±0.6),(2.1±0.6) vs (2.4±0.7), P<0.05]. Compared with group B, the incidences of chill, nausea and vomiting were lower in group A (0 vs 6, 1 vs 7, P<0.05). Conclusions Continuous intravenous pumping of Dex combined with morphine in epidurale in cesarean sections can decrease stress response, adverse effects of puerpera and satisfied analgesia effects.