Dexmedetomidine Prevent Adverse Reactions After The Combined Spinal-Epidural Anesthesia

Objective:This placebo-controlled study by studying the different loading dose medetomidine (Dex) vein pump injection to prevent Transurethral resection of bladder tumor or the urethra prostate electricity cut method intraoperative and postoperative adverse reactions (shivering and sedative effect), in Combined spinal anesthesia,(CSEA). Recording what happens to the drug adverse reactions, As anesthesia for the auxiliary medicine to guide clinical application.Method:80cases of urological surgical patients (ASA Ⅰ-Ⅲ)was Selected with Transurethral resection of bladder tumor or the urethra prostate electricity cut method under combined spinal anesthesia,(CSEA). from July to september2013,80patients with20units can be divided into four groups (n=20):(1) blank control group:After anesthesia plane stability, normal saline being pumped into vein10ml/h until the end of surgery;(2) Dexmedetomidine AH group:After anesthesia plane stability, high-loading-dose Dexmedetomidine being pumped into vein0.6μg/kg, after10minutes maintenance dose of0.2μg/kg-h intravenous pumping until the end of surgery;(3) DexmedetomidineAM group:After anesthesia plane stability, loading-dose Dexmedetomidine being pumped into vein0.4μg/kg, after10minutes maintenance dose of0.2μg/kg-h intravenous pumping until the end of surgery;(4) Dexmedetomidine AL group:After anesthesia plane stability, loading-dose Dexmedetomidine being pumped into vein0.2μg/kg, after10minutes maintenance dose of0.2μg/kg-hintravenous pumping until the end of surgery; Observations include:common items:Including the patient’s name, case number, male/female, age, intraoperative transfusion amount, surgery patient’s body condition assessment (ASA classification,), intraoperative Bladder or urethra flushing volume, weight, intraoperative urinary volume, operation time, intraoperative mood changes.Experimental data:Careful monitoring and detailed record each group(T0,T1,T2,T3,T4, T5), The circulatory system related indicators:blood pressure, heart rate (HR); The respiratory system related indicators:respiratory frequency (RR), pulse oxygen saturation (SpO2),; The temperature evaluation index:Oral temperature (T), Chill time and degree, depth of sedation.and Ramsay sedation score(RSS).After entering the room or before anesthesia (T0), The level of anesthesia is stable or the beginning of pump (T1); beginning of operation (T2) ending of operation(T3) lhour postoperation(T4);24hours postoperation (T5) Time and severity of shivering were recorded. Careful observation and peri operation period of the occurrence of adverse reactions recorded including dry mouth, nausea, vomiting, respiratory depression (RR <10beats/min or SpO2<90%), bradycardia (HR<40times/min). emotional states, Inquire and record at the end of operation patients complain of cold or other discomfort.The assessment criteria:(1) Oral temperature (electronic thermometer):32-35℃is defined as Mild hypothermia;30～32℃is defined as moderate hypothermia;<30℃is defined as severe hypothermia,23～25℃is defined as lethal hypothermia。(2) According to the regulations of the American society of anesthesiologists Shivering of classification standard:Level1for minor fibrillation face or neck with no upper limb ECG interference of voluntary movement。 Level2More than one group of muscles trembling; Level3, large group of muscles jitter, bed board for the whole body shaking can’t independent. Chills after2minutes don’t disappear, judged chills.(3) Ramsay sedation scores (RRS) standard:1score, The patient obviously showed be agitated2scores, The patient is in a state of calm,3scores, drowsiness, the patients only response to command;4scores, sleep, can wake up;5scores, sleep, Respond only to the strong stimulation, and slow;6scores, patients in a state of deep sleep, and call don’t wake up.(4) Absolute and relative bradycardia is defined as per minute the heartbeat<40or below30%, lower than the value before infusionStatistical analysis of data using statistical software (SPSS19.0) the measurement data are presented as mean±standard deviation, group and within-group comparisons using t test, The X2test for categorical data. To determine the data must meet P<0.05).Results:After statistical comparison within groups:HR in AH(high dose) group after the drug venous pump injection (T2\T3\T4) decreased significantly compared with T0(P<0.05),There are even bradycardia.(T2\T3\T4) HR in AM (middle dose)、 AL(low dose) group after the drug venous pump injectiondecreased significantly compared with T0(P<0.05), But not to the bradycardia diagnostic criteria.In blank control C group, HR, Shivering scoreand Ramsay sedation score was not statistically significant T1, T2, T3, T4and T5time compared with To (P>0.05); After each experimental drugs (T1, T2, T3, T4and T5) of MAP, SPO2, RR compared with T0difference is not obvious (P>0.05). AH, AM and AL three groups in T3, T4Ramsay sedation score compared with TO have statistical significance (P<0.05), the score height is proportional to the dose.Comparison between groups:Ramsay score in AH. AM、and AL group after the drug pump injection (T2\T3\T4) were higher than C group (P<0.05), and Ah group Ramsay score>AM group Ramsay score>AL group Ramsay score, all statistically significant (P<0.05). Postanaesthetic shivering was seen in9patients in group C(45%),0patient in group AH(0%),0patient in group AM (0%) and3patients in group AL(15%).The rate of shivering in AH. AM. AL group significantly compared with C group (P<0.05), There were2patients with nausea but without vomiting in group C. There were2patients with bradycardia and dry mouth. The rest of the group without adverse drug reactions.Conclusion:After anesthesia plane stability, loading-dose Dexmedetomidine being pumped into vein0.4μg/kg, after10minutes maintenance dose of0.2μg/kg-h intravenous pumping until the end of surgery; In Urology surgery under Combined spinal anesthesia, It can effectively reduce the incidence and severity of intraoperative and postoperative shivering, without adverse drug reactions. Its sedation effect also has excellent performance, and little effect for breathing, basic no nausea and vomiting, etc, for the comfort of anesthesia clinical drug selection provides a good reference.