【Abstract】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 T1 (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 T1 (P <0.01). While those were increased over 15% in groupIBW compared with T1(P<0.01). (3)The incidence of SBP>30% baseline, HR>100/min and RPP>12000 were highest in groupIBW(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 ASA Ⅰ~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.
