肌肉注射右美托咪定对腰硬联合麻醉患者术中镇静效应的影响

目的观察单次肌肉注射不同剂量右美托咪定(dexmedetomidine,Dex)用于腰硬联合麻醉(CSEA)患者术中镇静的有效性及安全性。方法 CSEA下行择期腹式全子宫切除术的患者100例(ASAⅠ～Ⅱ),随机分为5组(n=20),空白对照组(C组)及Dex组(D1、D2、D3、D4组)。各组分别于CSEA麻醉平面稳定后肌肉注射Dex 0、1.5、2.0、2.5、3.0μg/kg。入室后每隔5 min连续记录患者的血压、心率、脉搏血氧饱和度及脑电双频指数,肌肉注射Dex后每5 min进行1次警觉/镇静(OAA/S)评分,记录用Dex后24 h内低血压、高血压、窦性心动过缓、牵拉反应、寒战、头晕、过度镇静、术后躁动、呼吸抑制等不良反应的发生率及患者的总体镇静满意度评分。结果随着Dex剂量的增加,患者镇静满意度增加,但D4组有50%患者出现过度镇静,D2、D3、D4组镇静起效时间比较差异无统计学意义(P>0.05),约为15 min,但随着剂量的增加Dex镇静达峰时间有所延迟。与C组比较,D1、D2组患者低血压的发生率增加,D3、D4组窦性心动过缓的发生率增加。结论肌肉注射2.5μg/kg Dex可为CSEA下行腹式全子宫切除的患者提供满意的术中镇静,但需留意可能出现窦性心动过缓。

Sedative effects of intramuscular dexmedetomidine for patients with combined spinal-epidural anesthesia

Objective To evaluate the sedation efficacy and safety of intramuscular dexmedetomidine(Dex) in patients with elective abdominal hysterectomy using combined spinal-epidural anesthesia(CSEA).Methods One-hundred patients scheduled for elective abdominal hysterectomy were enrolled and randomly divided into 5 groups(n=20).The control(C) group and the other 4 groups(D1,D2,D3 and D4) were given intramuscularly injection of 3 mL normal saline and Dex with 0,1.5,2.0,2.5 and 3.0 μg/kg,respectively.SBP,DBP,HR,pulse oxygen saturation(SpO2),bispectal analysis index were recorded every 5 min after the patients entered operating room.The assessment of alertness/sedation scale(OAA/S) was evaluated every 5 min after Dex or normal saline was given intramuscularly.The overall sedative satisfaction and related complications(hypotension,hypertension,bradycardia,shivering,and et al.) was followed up in 24 h.Results Flowing with the increase of Dex,the overall sedative satisfaction degree was increased.Compared with Group D1 and D2,the patients in Group D3 and D4 were more satisfied with the sedation effects,while the over sedation rate(50%) in group D4 was significantly higher than those in other groups(P<0.05).Although there was no significant difference in the onset time of sedative effect among D2,D3 and D4 group,which were about 15 min,the peak sedative effects were delayed in a dose-dependent manner with the increase of Dex.Compared with that in Group C,the incidences of hypotension in group D1 and D2 were higher,and so were the incidences of bradycardia in group D3 and D4.Conclusion Intramuscular 2.5 μg/kg Dex can provide satisfactory sedative effect for the patients with elective abdominal hysterectomy unsing CSEA,though the Dex-induced bradycardia should be concerned.