右美托咪定用于无痛纤维支气管镜检查最佳负荷剂量的探讨

Discussion on the Best Loading Dose of Dexmedetomidine in Treatment of Painless Fiberbronchoscopy

目的：观察右美托咪定复合靶控输注丙泊酚-瑞芬太尼用于无痛纤维支气管镜检查的效果,并探讨右美托咪定的最佳负荷剂量。方法：选择200例择期行无痛纤维支气管镜检查的患者,采用随机数字表法分为右美托咪定不同剂量观察组（观察1、2、3组）和对照组。诱导前,观察1、2、3组患者分别给予0.2、0.4、0.6μg/kg的右美托咪定负荷剂量10 min静脉泵注;对照组给予等容量的0.9%氯化钠注射液。诱导时和检查中均采用麻醉/脑电意识监测系统（Narcotrend）监测麻醉深度以调整丙泊酚用量,术中4组患者均给予丙泊酚和瑞芬太尼靶控静脉输注维持。分别记录麻醉前（T_0）、诱导后（T_1）、镜入声门即刻（T_2）、镜达隆突即刻（T_3）、检查完成即刻（T_4）、检查完成后10 min（T_5）时患者的平均动脉压（MAP）、血氧饱和度、心率、警觉/镇静评分（observer＇s assessment of alertness/sedation scale,OAA/S）,记录丙泊酚的总用药量、不良反应及苏醒时间。结果：与T_0时点比较,T_1~T_4时点4组患者的OAA/S评分、MAP明显降低,T_2时点对照组患者的心率明显增快,差异均有统计学意义（P〈0.05）。与对照组比较,观察1、2、3组患者在T_5时点的OAA/S评分、Narcotrend指数升高,在T_1时点MAP明显升高,差异均有统计学意义（P〈0.05）;观察1、2组患者在T_2、T_3时点,以及观察3组患者在T_4、T_5时点的MAP明显降低,差异均有统计学意义（P〈0.05）;观察2、3组患者丙泊酚、瑞芬太尼用量明显减少,观察2组患者苏醒时间缩短,差异均有统计学意义（P〈0.05）;观察1、2、3组患者低血压、低氧血症发生率降低,观察3组患者窦性心动过缓发生率升高,差异均有统计学意义（P〈0.05）。结论：给予右美托咪定负荷剂量0.4μg/kg静脉泵注后,在Narcotrend监测下靶控输注丙泊酚-瑞芬太尼用于无痛纤维支气管镜检查,可以减少丙泊酚、瑞芬太尼的用量,减轻对呼吸循环的影响,缩短患者的苏醒时间。

OBJECTIVE：To observe the effects of dexmedetomidine combined with propofol-fentanyl in target controlled infusion on painless fiberbronchoscopy , and discuss the best loading dose of dexmedetomidine .METHODS：200 patients accepting painless fiberbronchoscopy were selected to be divided into three observation groups with different dose of dexmedetomidine （ observation group 1, 2 and 3） and the control group.Before induction, the observation group 1, 2 and 3 were given dose of 0.2, 0.4 and 0.6 μg/kg dexmedetomidine with 10 min intravenous pumping;and the control group received the equal volume 0.9%sodium chloride injection .Depth of anesthesia were monitored by Narcotrend during induction and examination so as to adjust the dosage of propofol , 4 group of patients were treated with propofol-fentanyl in target controlled infusion .The MAP, SpO2 , HR and observer’s assessment of alertness/sedation scale （ OAA/S） in T0 , T1 , T2 , T3 , T4 and T5 were respectively recorded , and the total consumption amount of propofol , adverse drug reactions and recovery time were recorded .RESULTS：Compared with T0 , the OAA/S score, MAP in T1-T4 decreased significantly , the HR of control group in T2 increased significantly , with statistically significant difference （ P 〈0.05 ）.Compared with control group, the OAA/S score, Narcotrend indicators of observation group1, 2 and 3 in T5 increased, yet MAP in T1 increased significantly , with statistically significant difference（P〈0.05）.The MAP of observation group 1,2 in T2 and T3 and observation group in T4 and T5 decreased significantly , the difference was statistically significant （ P〈0.05 ） .The dose of propofol and fentanyl in observation group 2,3 decreased significantly , the recovery time of observation group 2 shortened, the difference was statistically significant （ P〈0.05 ） .The incidence of hyoxemia of observation group 1 , 2 and 3 decreased , yet the incidence of sinus bradycardia in observation group 3 increased , with statistically significant difference （ P〈0.05 ） . CONCLUSIONS：When given loading dose of 0.4 μg/kg dexmedetomidine in intravenous pumping , patients with propofol-fentanyl in target controlled infusion on painless fiberbronchoscopy under monotoring of Narcotrend can receive less propofol and fentanyl , which can relief the effects on cardiopulmonary circulation and shorten the recovery time .