以去脂体重为标准计算静脉全麻诱导剂量对重度肥胖病人的影响

Effect of lean body weight as a criterion to calculate intravenous induction dose in general anesthesia for severe obese patients

目的探讨重度肥胖病人以去脂体重为标准计算全麻静脉诱导剂量对气管插管心血管反应。方法选取ASAI～II级、年龄18～60岁、体重指数(BMI)≥40、手术时间<2小时,择期在全麻下行普通外科与骨科手术的患者30例,按照全麻诱导用药剂量的计算方法随机分为三组:去脂体重给药组(LBW组),总体重给药组(TBW组)和理想体重给药组(IBW组),患者均采用静脉麻醉诱导。取入室后前三个收缩压(SBP)、舒张压(DBP)和心率(HR)的平均值作为基础值(T1),分别记录并比较各组患者麻醉诱导后插管前(T2)、插管后即刻(T3)的HR、SBP和DBP以及拔管时间(术毕至拔管的时间),计算并比较各组心率与收缩压的乘积(Cardiac rate-pressure product,RPP),比较各组不良反应的发生情况。结果 (1)在T2时刻,与T1比较,TBW组患者SBP、DBP和HR下降的幅度明显大于LBW组和IBW组(P<0.01);(2)在T3时刻,与T1比较,TBW组和LBW组患者的SBP、DBP和HR均有所下降,且TBW组下降的幅度明显大于LBW组(P<0.01);而IBW组患者的SBP、DBP和HR均有所升高,且升高的幅度大于15%(P<0.01);(3)不良反应的发生情况:三组比较,SBP升高>30%、HR>100次/min和RPP>12000的发生率为IBW组最高(60%、50%、80%,P<0.01);SBP下降>30%和HR<60次/min的发生率均为TBW组最高(70%、50%,P<0.01);(4)三组比较,拔管时间TBW组最长(26.2±12.5min,P<0.01)。结论对于无基础疾病的重度肥胖病人,以LBW作为标准计算静脉麻醉诱导剂量对循环的影响小,不良反应发生率低,苏醒快,更具合理性。

Objective To investigate the cardiovascular response and extubation time of severe obese patients undergoing tracheal intubation by using lean body weight （LBW） as a criterion to calculate intravenous induction dose. Methods Thirty patients, ASA Ⅰ～Ⅱ, aged from 18 to 60 years old, BMI〉40, who were scheduled to perform general and orthopedic surgery undergoing general anesthesia,were involved in this study. Patients who were given anesthetics according to their lean body weight （LBW）, total body weight （TBW） and ideal body weight （IBW）, were assigned into 3 groups：group LBW, groupTBW and groupIBW respectively. The average of three record of systolic pressure （SBP）, diastolic pressure （DBP） and heart rate （HR） were taken as base values （T1）. The SBP, DBP and HR of patients in three groups at the moment just before intubation （T2） and at the moment intubation （T3） as well as extubation time （time from the end of surgery to extubation） were recorded. Results （1） The decreases of SBP, DBP and HR in groupTBW at T2 were much more than that in groupLBW and groupIBW compared with T~ （P〈0.01）. （2） The decreases of SBP, DBP and HR in groupTBW were much more significant than that in groupLBW at T3 compared with Tt （P 〈 0.01）. While those were increased over 15% in grouplBW compared with T1（P〈0.01）. （3）The incidence of SBP〉30% baseline, HR〉100/min and RPP〉12000 were highest in grouplBW （60%, 50%, 80%, P〈0.01）, the incidence of SBP〈30% baseline and HR〈60/min were highest in group TBW（70%, 50%, P〈0.01）. （4） Extubation time in group TBW was longest （26.2±12.5 min, P〈0.01 ） among the three groups. Conclusion LBM may be considered as a reasonable criterion for ASAⅠ～Ⅱ, severe obese patients to calculate the induction dose of intravenous anesthetics since it has less impact on cardiovascular reaction ,lower incidence of adverse reaction and faster recovery from general anesthesia.