小剂量右美托咪定对既往脑卒中老年患者术后谵妄发生率的影响：对随机对照研究数据的二次分析

摘要

目的：观察预防性小剂量右美托咪定输注对既往脑卒中老年患者术后谵妄发生率的影响。方法161例既往合并脑卒中病史、术后入重症监护病房（ ICU ）的老年（≥65岁）患者，从入ICU起到术后次日晨随机接受小剂量右美托咪定[0．1μg／（kg· h），右美托咪定组，n＝82]或安慰剂（生理盐水）（对照组，n＝79）持续输注。采用ICU意识模糊评估法每日2次评估术后7 d内谵妄发生情况。结果术后7 d内谵妄发生率右美托咪定组（12例，14.6％）明显低于对照组（23例，29.1％，P＝0．026）。采用logistic回归分析校正混杂因素后，小剂量右美托咪定输注仍然是术后谵妄风险降低的独立影响因素（OR＝0．36，95％CI 0．15～0．89，P＝0．027）。试验药物输注期间低血压发生率右美托咪定组（35例，42．7％）明显高于对照组（19例，24．1％，P＝0．012），但低血压干预的患者比例两组间无明显差异。结论对于既往合并脑卒中、术后进入ICU的老年患者，术后预防性输注小剂量右美托咪定可以降低术后谵妄的发生，但需监测低血压的发生情况。%Objective To determine the effect of preventative infusion of low-dose dexmedetomidine ( DEX) on the incidence of postoperative delirium among the elderly patients with a history of cerebral stroke .Methods Based on our previous random , double-blind, pracebo control study , a total of 161 elderly patients (≥65 years old) with a history of cerebral stroke who were admitted to the intensive care unit ( ICU ) of our hospital after surgery from May 2011 to November 2013 were enrolled in this study .They were randomly assigned into DEX group [an infusion of 0.1μg/(kg· h) DEX, n=82] and placebo group (saline, n=79) in the morning from the second day after operation .Delirium was assessed twice daily with the Confusion Assessment Method for the ICU ( CAM-ICU) within 7 d after surgery .Results The incidence of postoperative delirium was significantly lower in the DEX group than the placebo group [12/82 (14.6%) vs 23/79(29.1%), P=0.026].After adjustment of confounding factors , multivariate logistic regression analysis showed that low-dose DEX infusion was an independent influencing factor for postoperative delirium ( OR=0.36, 95%CI:0.15-0.89, P=0.027).But the occurrence of hypotension was obviously higher in the DEX group than in the placebo group [42.7%(35/82) vs 24.1%(19/79), P=0.012], but no such difference was found between those who had the hypotension interven -tion from the 2 groups.Conclusion For the elderly patients with a history of cerebral stroke and transferred to ICU after surgery , postoperative prophylactic infusion of low-dose DEX could reduce the incidence of postoperative delirium , but hypotension should be monitored in the duration .