Résumé
Objective To evaluate the effects of different concentrations of sevoflurane on the left ventricular function of patients.Methods Forty patients of both sexes,aged 30-50 yr,with body mass index of 18-25 kg/m2,of American Society of Anesthesiologists physical status Ⅰ,were divided into Ⅰ,Ⅱ,Ⅲ,and Ⅳ groups (n =10 each) using a random number table.The end-tidal concentration of sevoflurane was set at 2％,3％,4％ and 5％ in Ⅰ,Ⅱ,Ⅲ and V groups,respectively.The parameters of left ventricular function were monitored using the ultrasonic cardiogram.Before induction of anesthesia (T0,baseline) and at 3,5,8 and 10 min after the end-tidal concentration of sevoflurane reached the target concentration (T1-4),the left ventricular end-diastolic diameter,left ventricular end-systolic diameter,left ventricular ejection fraction (LVEF),left ventricular fractional shortening,cardiac output (CO) and heart rate (HR) were recorded.Results The LVEF,CO and HR were within the normal range.Compared with those at T0,the LVEF,left ventricular fractional shortening and CO were significantly decreased at T2-4 in Ⅱ-Ⅳ groups,the left ventricular end-systolic diameter was increased at T2-4 in Ⅲ and Ⅳ groups (P＜0.05),no significant change was found in the left ventricular end-diastolic diameter and HR at each time point in Ⅲ and Ⅳ groups,and no significant change was found in the parameters mentioned above in group Ⅰ (P＞0.05).Conclusion Inhaling 2％ sevoflurane produces no marked effect on the left ventricular function,3％-5％ sevoflurane exerts inhibitory effect on the left ventricular systolic function,and has no effect on the left ventricular diastolic function of patients.
Résumé
Objective To evaluate effects of different concentration of sevoflurane anesthesia on left ventricular function in elderly patients by cardiac ultrasound.Methods One hundred and twenty patients (59 males,61 females,aged 65-69 years,ASA gradeⅠor Ⅱ)undergoing elective surgery having general anesthesia were divided into 4 groups according to minimum alveolar concentration (MAC)using random number table method,30 in each.To maintain the MAC at 1.0,1.5,2.0,2.5,fentanyl and suc-cinylcholine were used for rapid induction,followed by endotracheal intubation.Mechanical ventilation was maintained at the preset value for 10 minutes,then the concentration of sevoflurane was adjusted.Left ven-tricular end-diastolic diameter (LVEDD),left ventricular end-systolic diameter (LVESD),left ventricular ejection fraction (LVEF),left interior diameter shortening rate (LVFS),cardiac output by cardiac ultra-sound,noninvasive arterial systolic pressure,diastolic pressure,heart rate were recorded prior to the induc-tion (T0 )and after 3 min (T1 ),5 min (T2 ),8 min (T3 ),10 min (T4 )of reaching the target concentra-tion.Cardiovascular event was also documented if there was any during the study.Results Compared with T0 ,the systolic pressure and diastolic pressure of 4 groups decreased at T1-T4 time point,LVEF,LVFS and cardiac output of group S2,S3,S4 decreased at T2-T4 time point,LVESD of group S3 and S4 increased at T2-T4 time point,with significant differences (P <0.05).Compared with group S1,group S2,S3 and S4 at T2-T4 time point,LVEF,LVFS and cardiac output decreased,LVESD of group S3 and S4 increased, the difference being statistically significant (P <0.05).Compared with group S2,LVESD of group S3 and S4 increased with significant difference (P <0.05).No hypotension occurred in group S1 and S2.Hypoten-sion in group S3 and S4 occurred in a rate of 20% and 30% respectively.Compared with group S1 and S2, the incidence of hypotension of group S3 and S4 increased (P <0.05).Conclusion Low concentration of sevoflurane anesthesia exerts no obvious effect on left ventricular function of elderly patients,however high concentration of sevoflurane anesthesia has obvious inhibition on left ventricular systolic function,but had no effect on left ventricular diastolic function.