Study On The Inhibition Of Remifentanil - Mediated Acute Hyperalgesia After Surgery

Objective：To observe the effects of epodural butorphanol on remifentnil-inducedpostoperative hyperalgesia.Methods:Sixty patients，of ASA Ⅰor Ⅱ，combined epidural/general anesthesia on theVideo-assisted thoracic surgery (VATS),were divided randomly into three groups:BMgroup (subgroup1),B group (subgroup2)and M group (control group).Place thesegmental epidural catheter after epidural anesthesia at T5-6or T6-7,three guoups wereinduce with midazolam,propofol,cisatracurium,remifentanyl injection and double-lumenendobronchial intubation.Remifentanil and propofol with target controlled infusionwere used during operation,combined sodium chloride and hetastarch intravenousinfusion.Epidural dose was administered30minutes before operation endding,analgesiaformula was as follows:BM group,butorphanol1mg plus morphine1mg;Bgroup,butorphanol2mg;M group,morphine2mg.The patients extubed were transferredto bed-ward after operation and revival.The patients of three groups were recorded bythe MAP,HR,RR,SpO2,VAS scores,Ramesay scores in the point enddinganesthesia,1h,2h,4h,6h,24h,and the situation of using dolantin,of pruritus,of nausea andvomiting after operation.Results：1All the patients of the three group got satisfaction effect to inhibiting OIH,therewere no significant difference in VAS among the three groups at the point endinganesthesia,1h,2h and4h after operation(P>0.05),but the analgetic time of BM group andM group were longer than B group(P<0.05),the first time using dolantin of B group wasearlier than BM group and M group,the dose of intramuscular injection of B groupwas more than BM group and M group (P<0.05).2Ramesay scores of B group washigher than M group at the point ending anesthesia,1h,2h and4h after operation(P<0.05),Ramesay scores of BM group was higher than M group at the point ending anesthesia (P<0.05),all the three groups had no respiratory depression.3the PONVoccurrence rate of BM group and B group were lower than M group (P<0.05),the firsttime using tropisetron of B group was earlier than M group (P<0.05),the dose ofintravenous infusion tropisetron of BM group and B group are less than M group(P<0.05);the pruritus occurrence rate of BM group and B group were lower than Mgroup (P<0.05),the dose of intravenous infusion dexamethasone of BM group and Bgroup are less than M group (P<0.05).Conclusion:Butorphanol1mg plus morphine1mg epidural is obviously valid in inhibitingeffects on remifentanil-induced postoperative hyperalgesia, longer analgetic time isprovided, without increasing the PONV and pruritus occurrence rate,and it can makepatient feel more comfortable.