腹腔镜手术中笑气对右美托咪定致心动过缓的预防作用

Effect of nitrous oxide inhalation in preventing bradycardia following dexmedetomidine administration in laparoscopic surgery

目的探讨腹腔镜手术中笑气对右美托咪定所致心动过缓的预防作用。方法选取2019年3-9月福建医科大学附属第一医院择期行全身麻醉(全麻)腹腔镜手术患者145例,美国麻醉医师协会(ASA)分级Ⅰ~Ⅱ级,年龄18~70岁。根据随机数字表法将其分为笑气组(n=72)和对照组(n=73)。全麻维持期笑气组吸入50%氧化亚氮(N2O),对照组无N2O吸入。2组切皮前10min均经微量泵给予0.5μg/kg右美托咪定输注15min。记录患者入室时(tBL)、右美托咪定输注即刻(t0)及之后30min内每5分钟(t5~t30)的心率、收缩压、平均血压、舒张压。记录术中是否发生心动过缓(心率低于50次/分)、低血压、高血压和血管活性药物的使用情况。结果笑气组心动过缓发生率明显低于对照组[20.8%vs.38.4%,风险比(RR)=0.543,95%可信区间(95%CI)0.318~0.928,P<0.05]。2组各时间点血压,心率,需药物干预的心动过速、低血压和高血压发生率比较,差异均无统计学意义(P>0.05)。结论全麻腹腔镜手术中输注负荷量右美托咪定前吸入50%N2O对心动过缓的发生具有一定预防作用。

Objective To explore the preventive effect of nitrous oxide(N 2O)on bradycardia induced by dexmedetomidine in laparoscopic surgery.Methods A total of 145 patients with elective laparoscopic surgery under general anesthesia in the First Affiliated Hospital of Fujian Medical University from March to September 2019 were randomly divided into the nitrous oxide group(n=72)and the control group(n=73)by random number table method.The patients were graded gradeⅠ-Ⅱby the American Association of Anesthesiologists(ASA),and their ages ranged from 18 to 70 years old.During the maintenance period of general anesthesia,50%N 2O was inhaled in the nitrous oxide group,while no N 2O was inhaled in the control group.10 min before skin incision,a loading dose of dexmedetomidine(0.5μg/kg)was infused by micro pump for 15 min in both groups.The heart rate,systolic blood pressure,mean blood pressure,diastolic blood pressure were recorded at patients entering the operating room(t BL)and dexmedetomidine infusion immediately(t 0)and every 5 min(t 5-t 30)within 30 min.The whether bradycardia(heart rate<50 times/min)occurred intraoperatively,hypotension,hypertension,and use of vasoactive agents were recorded.Results The incidence of bradycardia in nitrous oxide group was significantly lower than that in control group[20.8%vs.38.4%,risk ratio(RR)=0.543,95%confidence interval(95%CI)0.318-0.928,P<0.05].However,there were no statistically significant differences in the incidence of hypotension,hypertension,tachycardia needing pharmacological intervention,and heart rate,blood pressure at each time point between the two groups(P>0.05).Conclusion Before dosing dexmedetomidine during laparoscopic surgery under general anesthesia,inhalation of 50%N 2O can prevent bradycardia.