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.

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.

Objectives To assess the value of external anal sphincter electromyography (EASEMG) in evaluating the related autonomic dysfunction in Parkinson's disease ( PD), parkinsonism dominant multiple system atrophy (MSA-P) and progressive supranuclear palsy (PSP). Methods From the records of EAS-EMG collected in our lab (total 562 cases), 60 PD (male 41, female 19), 68 MSA-P (male 35,female 33) and 13 PSP (male 10, female 3) were included in the analysis in this study. Mean duration,polyphasic ratio and satellite potential occurrence rate were comparable among the groups. Mean duration prolongation were graded as normal ( ＜ 10.0 ms), mild ( 10.0-11.9 ms), moderate ( 12.0-13.9 ms)and severe ( ≥ 14.0 ms). Results Among all related autonomic symptoms, the occurrence rate of constipation, urinary incontinence, urgency and frequency in patients with MSA-P(95.8% (23/24) ,94.6% (53/56) ,87.7% ( 50/57 ), 85.7% (42/49), 76.5% ( 39/51 ) ) were higher than that of PD ( 61.5%(16/26), 62.3% (33/53), 30.6% (15/49), 46.2% (24/52), 45.7% (21/46)) and PSP (75.0%(3/4) , 62.5% (5/8), 50.0% (4/8), 42.9% (3/7), 42.9% (3/7)). The abnormal rate of EAS-EMG in PD, MSA-P and PSP were 60.0%, 94.2% and 84.6%, accordingly. Mean duration ( PD ( 12.0 ± 1.6)ms, MSA-P (15.4±3.0) ms, PSP (13.8±1.8) ms), polyphasic ratio (PD 46.2% ±19.2%, MSA-P 63.9% ± 15.8%, PSP 51.5% ± 12.1% ) and satellite potential occurrence rate ( PD 9.5% ± 8.3%,MSA-P 26.5% ± 15.9%, PSP 19.2% ± 12.5% ) varied significantly different among the groups ( F =31.724, F = 17.412, x2 =45. 335, all P ＜0.01 ). Severe mean duration prolongation was overwhelming in MSA-P (66.2% ) , compared with mild 10.3% and moderate 23.5%. The predominant prolongation degree was moderate in PSP (61.5%, mild 7.7%, severe 30.8% ), and mild in PD (36.7%, moderate 36.7% ,severe 11.7%, normal 15.0% ). Conclusions EAS-EMG could play a role in evaluating the related autonomic dysfunctions in PD, MSA-P and PSP. The EAS-EMG impairment was severe and frequent in MSA-P, mild and infrequent in PD, moderate in PSP. The spectrum of mean duration prolongation suggested the possibility of Onuf's nucleus involvement in these diseases.

Objective To investigate the underlying mechanisms of Miller-Fisher syndrome (MFS) and Bickerstaff' s brainstem encephalitis (BBE) by studying their clinical and electrophysiological characteristics.Methods The clinical and electrophysiological characteristics of 13 MFS and 7 BBE cases in Peking Union Medical College Hospital between 2000 and 2011 were retrospectively analyzed.The electrophysiological parameters included sensory and motor nerve conduction,electromyography,F wave,sympathetic skin response and brainstem auditory evoked potential and blink reflex.Results MFS and BBE had similar clinical characteristics:respiratory symptoms were the most common infectious symptoms before disease onset; Ophthalmoplegia,facial palsy and bulbar symptoms were common; They both had cerebrospinal fluid albuminocytological dissociation and positive serum anti-GQ1b antibody.However,BBE had more central nervous system lesion signs clinically such as conscious disturbance,positive Babinski' s sign and central facial palsy.Electrophysiologically,MFS and BBE also had similar electrophysiological features:sensory nerve abnormality ratios were 6/13,2/7 respectively,with prominently reduced sensory nerve active potential amplitude,normal or slightly slowed sensory conduction velocity; Motor nerves abnormality ratios were 2/13,1/7 respectively,with slightly prolonged distal motor latency and normal compound muscle action potential; Electromyography abnormality ratios were 1/7,0/4 respectively; F wave frequency abnormality ratios were 3/13,5/7 respectively,and in some cases,F wave frequency would restore; Sympathetic skin response abnormality ratios were 1/2,1/3 respectively; Blink reflex abnormalityratios were 1/2,1/1 respectively,with central involvement in BBE; Brainstem auditory evoked potential abnormality ratios were 3/5,1/4 respectively,with wave Ⅰ latency or amplitude abnormality.Conclusion The similarities of clinical and electrophysiological features suggest that MFS and BBE have the same mechanism and they form a continuous spectrum with variable central nervous system and peripheral nervous system involvement.