Clinical Application Of Preemptive Combined With Patient-controllcd Analgesia With Dcxmcdetoniidine In Lower Limb Orthopedic Surgeries

Objective Dexmedetomidine is a highly selective alpha2-adrenocepto agonist,whichpossesses the characteristics such as sedation,analgesia,anti-anxiety, anti-sympathetic,hemodynmic stablityand lack of respiratory depression and arousable sedation aresignificant properties,And it can reduce the dosage of anesthetic and opioiddrugs,decrease postoperative adversereactions such as nausea,vomiting andagitation,Consequently,the important value of clinical application isrepresented. Researchers investigate the effect of dexmedetomidine during theperioperative time more attentionally，however, Less reporting on the supplement topostoperative analgesia.This experiment was to explorer the effect of preemptivecombined with patient-controlled analgesia with dexmedetomidine in lower limborthopedic surgeries.Methods By consent of the hospital’s ethics committee and subjects Signed informedconsent the day before their surgeries,ninety patients undergoing selective orthopediclower limb surgery were randomized equally divided into group C(n=30),groupD1(n=30)and groupD2(n=30),The age of these patients ranges from21to63, ASA I~II level.After the operating room,patients were carried out routine monitoring and openedperipheral vein to receive fluid intravenously.Three groups were administered withcombined spinal-epidural anesthesia (CSEA).Informing subjects adopting the lateralposition,the L2-3or L3-4was selected to perform spinal-epidural puncture,the dosageof spinal anesthesia was administrated0.3%hypobaric bupivacain3ml,epiduralcatheters were successuflly inserted to the head,Patients were placed the horizontalposition after determining level of anesthesia.During operation when spinal analgesiawas inadequate, A single addition0.375%bupivacain5-10ml was supplemented viaepidural catheter according to the surgery and the operation time was record.Group Creceived sulfentany2μg/kg·2d-1+flurbiprofen150mg·2d-1+azasetron10mg·2d-1.GroupD1received sulfentany2μg/kg·2d-1+flurbiprofen150mg·2d-1+azasetron10mg·2d-1+Dex4μg·kg-1·2d-1.Group D2received loading dose of Dex(0.5μg/kg over10min), followed by a continuous infusion at a rate of0.05μg/kg/h to the end ofsurgery,and postoperatively receiving sulfentany2μg/kg·2d-1+flurbiprofen150mg·2d-1+azasetron10mg·2d-1+Dex4μg·kg-1·2d-1.After operation, the corresponding PCA waslinked,The analgesic pump was set in the three groups a follows:continuous perfusionrate3ml/h, single bolus1ml, lockout time20min, total volume150ml With0.9%saline solution.Pain intensity was assessed with visual analog scale (VAS),the degreeof sedation was assessed by using Ramesay sedation score at the time of0h,6h,12h,24hand48h after surgeries.at th same time,collecting the Heart rate (HR), systolic bloodpressure (SBP), diastolic blood pressure (DBP), pulse oxygen saturation (SPO2),Thenumber of patient-controlled press of the pump in the first24hours and the incidenceof side effects as well as Nausea, vomiting, chills, itching and respiratory depressionwere recorded after the surgery,and made the correspondening side effect scores. Results (1) There was no statistic difference among the three groups in the patients’age, weight,height, the time of the operation, the number of press of the pump.(2) When SBP, DBP, HR, SPO2of the three groups were compared within0hours,6hours,12hours,24hours and48hours after the operation, the hemodynamic status ofthe group D2was more stable than the group D1,C.SBP, DBP, HR of the group D1,D2were significantly decreased compared with the group C （**P<0.01）.the three groups’patients did not have respiratory depression,SpO2fluctuated from96%to100%.(3) VAS scores in the group D1were reduced vs the group C (*P<0.05),thus VASscores in the group D2were remarkably reduced vs the group C(**P<0.01)during6~24hours after the operation, there was no significant difference between the group D1andthe group D2,while during24~48hours there was no significant difference among threegroups.(4) Sedation scores in the group D2were clearly higher vs the group C during24hoursafter the operation(**P<0.01),Sedation scores in the group D1were clearly higher vs thegroup C during6-24hours after the operation(**P<0.01),the drowsiness occurred in fivecases from the group D1,and the drowsiness occurred in seven cases from the group D2.(5) The incidence of nausea,vomiting,chills of the group D1,D2is less than that of thegroup C,while the incidence of nausea and chills of group D1was more than that of thegroup D2, no vomiting was found in two groups, no respiratory depression and skinpruritus among the three groups. Conclusions In the appropriate drug doses,This method can improve the qualityonpostoperative analgesia by the preemptive combined with patient-controlled analgesiawith dexmedetomidine in lower limb orthopedic surgeries, and it can reduce thehappeness of adverse effect．But we should pay more attention to the phenomenon aswell as excessive sedation and bradycardia the monitoring shall be strengthenedif necessary,then events of responding adverse drug reactions were avoided.