Objective To evaluate the effect of sevoflurane on left ventricular function in patients undergoing elective coronary artery bypass grafting (CABG) .Methods Thirty-five ASA Ⅱ or Ⅲ patients of both sexes (30 males, 5 females) aged 53-75 yr weighing 46-100 kg undergoing CABG were enrolled in this study. Transesophageal echocardiography (TEE) probe was placed. The TEE variables including cardiac index (CI), left ventricular short axis shortening (FS), left ventricular ejection fraction (LVEF), low propagation velocity ( Vp), E wave velocity (E) , A wave velocity ( A) , systolic wave velocity ( S) , diastolic wave velocity ( D), AR wave velocity, E/A ratio and S/D ratio were recorded before inhalation of sevoflurane (T_1 ) , and 5 min (T_2) and 15 rain ( T_3) after inhalation of sevoflurane after splitting of sternum, and before inhalation of sevoflurane (T_4 ), 5 min (T_5) and 15 min (T_6) after inhalation of sevoflurane after the closure of sternum. The end-tidal concentration of sevoflurane corresponded to 1 MAC. Anesthesia was induced with midazolam 0.05 nig/kg, sufentanil 0.5μg/kg and rocuronium 0.9 mg/kg and maintained with infusion of propofol at 4-6 mg·kg~(-1) ·h~(-1), remifentanil at 0.2-0.4μgkg~(-1)·h~(-1) and atracurium at 0.5 mg·kg~(-1)·h~(-1). The patients were mechanically ventilated after tracheal intubation (V_T 8 ml/kg, RR 12 bpm, I:E 1:2, FiO_2 70%-80% ) .Results (1) MAP and CI were significantly decreased at 5 and 15 min after sevoflurane inhalation. LVEF and FS were also decreased. (2) There was no significant change in diastolic function indexes after sevoflurane inhalation including E and A wave velocity, systolic wave velocity, diastolic wave velocity, E/A ratio and S/D ratio. (3) Cardiac function improved after CABG. CI, LVEF and FS were significantly increased after CABG as compared with preoperative values. Conclusion In patients undergoing elective CABG, sevoflurane (the end-tidal concentration corresponding to 1 MAC) can depress left ventricular systolic function but does not affect left ventricular diastolic function.

BACKGROUND:Previous studies demonstrated that ischemia can be compensated by establishing collateral circulation and microangiogenesis,and exercise training can ameliorate blood supply of ischemic lower limb.However,whether exercise training accelerate establishment of collateral circulation remains poorly understood.OBJECTIVE:To explore the mechanism of exercise training on accelerating microangiogenesis of rat ischemic lower limb.METHODS:Sprague-Dawley rats were randomly divided into the exercise training,model and sham-surgery groups.All animals were established left lower limb ischemia models except those in the sham-surgery group.Rats in the exercise training group were forced running 30 minutes per day at 1 week after model preparation and those in other groups were performed daily activities.The adductor of ischemic lower limb was obtained for the examination of microvessel density and the expressions of vascular endothelial growth factor and basic fibroblast growth factor.Simultaneously,bone marrow-derived endothelial progenitor cells were harvested for detection of microangiogenesis.RESULTS AND CONCLUSION:Number of endothelial progenitor calls,expressions of vascular endothelial growth factor and basic fibroblast growth factor,as well as microvessel density of the exercise training group was obviously greater than those in the model and sham-surgery groups(P<0.01).Compared with the model and sham-surgery groups,in vitro vasculogenesisof bone marrow-derived endothelial progenitor cells in the exercise training group was increased(P<0.05).These findings demonstrated that lower limb ischemia increases microangiogenesis,and exercise training enhances this effect.

Objective To evaluate the value of Disposcope-guided the left-sided double-lumen tube (DLT) intubation.Methods Fifty ASA physical status Ⅰ or Ⅱ patients,aged 47-69 yr,without difficult airway,scheduled for elective thoracic surgery,were randomly divided into 2 groups (n =25 each) using a random number table:Disposcope (group D) and Macintosh direct laryngoscope (group M).Anesthesia was induced with iv injection of midazolam,propofol,sufentanil and rocuronium.Before induction (baseline,T1),before intubation (T2),immediately after successful intubation (T3),and at 1 and 3 min after intubation (T4-5),systolic blood pressure (SBP),mean airway pressure (MAP) and heart rate (HR) were recorded,and rate-pressure (SBP) product (RPP) was calculated.Arterial blood samples were obtained at T1-5 for measurement of plasma epinephrine (E),norepinephrine (NE),and dopamine (DOPA) concentrations.The success rate of DLT intubation at first attempt,total success rate of DLT intubation,intubation time,and development of sore throat within 24 h after surgery were recorded.Results Compared with group M,the intubation time was significantly shortened,the success rate of DLT intubation at first attempt was increased,the incidence of sore throat was decreased,and the levels of MAP,HR,RPP,E,NE and DOPA were decreased at T3-5 in D group (P ＜ 0.05).Compared with the baseline value at T1,the levels of MAP,HR,RPP,E,NE and DOPA were decreased at T3-5 in M group (P ＜ 0.05),and no significant change was found in D group (P ＞ 0.05).Conclusion Disposcope-guided left-sided DLT intubation provides significant clinical value.

Objective To determine if the cardiac index (CI) measured by transesophageal echocardiography (TEE) through the mitral valve (MV) agrees with that measured by transesophageal echocardiography through the ascending aorta (AA).Methods Sixteen ASA Ⅱ or Ⅲ patients (NYHA Ⅱ or Ⅲ),aged 18-70 kg,weighing 46-72 kg,undergoing mitral valve replacement under cardiopulmonary bypass (CPB),were studied.Total intravenous anesthesia was used for induction and maintenance of anesthesia.After tracheal intubation,the TEE probe was placed in the esophagus.CI was measured by transesophageal echocardiography through the MV (CIMV)and AA (CIAA) at 15,30 and 60 min after termination of CPB and recorded.All the data were compared by Bland-Altman analysis.Results CIMV values were significantly lower at each time point than CIAA values (P ＜0.01).The results of Bland-Altman comparison:CIMV 1.29-5.52 L· min-1 · m-2,mean was (2.6 ± 0.9)L·min-1·m-2,and CIAA 2.7-8.8 L·min-1·m-2,mean was (4.9± 1.7) L·min-1 ·m-2,bias was-2.3 L·min-1 ·m-2,and limit of agreement was-5.62-1.03 L· min-1 · m-2 resulting in r =-0.577,P ＜ 0.01.Conclusion CI values obtained through the MV agrees well with that measured through the AA using TEE in patients undergoing mitral valve replacement,but CIAA values are significantly higher than CIMV values,there is a large difference between them for clinical use,and both methods for CI measurement cannot replace each other.

ObjectiveTo determine ff the cardiac index (CI) measured with FloTrac-Vigileo system agrees with that measured with pulmonary artery catheter (PAC).MethodsForty-three ASA Ⅱ or Ⅲ patients aged 53-75 yr weighing 46-100 kg undergoing off-pump coronary artery bypass grafting were included in this study.Anesthesia was induced with midasolam,sufentunil,propofol and rocuronium and maintained with propofol,remifentanil and atracurium.One MAC sevoflurane was inhaled at breast bone splitting and closing.CI was measured with FloTrac-Vigileo system and PAC before,and at 5,15 min of sevoflurane inhalation and recorded.All data were compared by Bland-Altman analysis and with kappa coefficient for agreement and percentage error was calculated.ResultsBland-Altman comparison of FloTrac-Vigileo system and PAC:matching data of 258 measurements:CI (2.8 ± 0.6 ) L· min - 1 · m- 2,bias was 0.23 L* min- 1 · m - 2 and limit of agreement was ( - 0.57,1.02)L · min- 1 · m- 2,resulting in κ ＝ 0.546 and an overall percentage error of 28.6 ％.ConclusionCI values obtained by FloTrac-Vigileo system agrees well with that obtained by thermodilution technique using PAC in patients undergoing off-pump coronary artery bypass grafting.

Objective To evaluate the accuracy of systolic pressure variation (SPV) in monitoring blood volume in patients.Methods Twenty-two ASA Ⅱ or Ⅲ patients (17 male,5 female),aged 49-79 yr,with body height 153-173 cm,weighing 55-89 kg,scheduled for elective coronary artery bypass grafting under cardiopulmonary bypass,were studied.Stroke volume variation (SVV) was monitored based on the arterial pressure wave and SPV measured based on the invasive arterial pressure wave after changing the title.After the chest was closed,the volume load test was immediately carried out.6％ hydroxyethyl starch 130/0.4 50-80 ml/min was infused via the jugular vein until cardiac index (CI) increased by 10％.HR,mean arterial pressure (MAP),SPV,CI,SVV,stroke volume index (SVI),systemic vascular resistance index (SVRI),central venous pressure (CVP),and pulmonary capillary wedge pressure (PCWP) were recorded in supine position (T1),at 30° head-down tilt before skin incision (T1'),before (T2) and after opening the chest in supine position (T2'),before (T3) and after the volume load test in supine position after closing the chest (T3'),in supine position after skin closure (T4),and at 30° head-down tilt after skin closure (T4').The difference in SPV and SVV (△SPV and △SVV) was calculated.The receiver operator characteristic curve for △SVV and △ SPV in determining blood volume changes was plotted.Results MAP,CVP,PCWP,CI,and SVRI were significantly increased,while SVV and SPV were decreased at T1' compared with those at T1 (P ＜ 0.05).HR was significantly increased,while CVP was decreased at T2' compared with those at T2 (P ＜ 0.05).MAP,CVP,PCWP,and CI were significantly increased,while SVV and SPV were decreased at T3' compared with those at T3 (P ＜ 0.05).MAP,CVP,and PCWP were significantly increased,while SVV and SPV were decreased at T4' compared with those at T4 (P ＜ 0.05).The area under receive operator characteristic curve for △SVV and △SPV in determining blood volume changes was 0.603 and 0.616 respectively,and there was no significant difference (P ＞ 0.05).Conclusion SPV can accurately monitor the blood volume in patients.

Objective To establish and confirm the hepatitis B surface antigen(HBsAg) enzyme linked immunosorbent assay(ELISA) high specificity S/CO limit as blood donor deferral criterion.Methods A total of 783 HBsAg ELISA reactive and 588 non-reactive samples were collected, and confirmed by HBsAg electrochemiluminescence detection and neutralization test.Receiver operating characteristic curve (ROC curve) was used to evaluate the S/CO limit under 95% and 99% specificity.Another 124 HBsAg ELSIA reactive samples were tested for five kinds of hepatitis B virus(HBV) markers by using electrochemiluminescence detection to verify the blood donor deferral limit.The blood donor deferral limits of 3 laboratories, using the same reagents, were compared.Results The 95% specificity S/CO limit of two reagents were 0.24 and 0.65, the 99% specificity S/CO limit of two reagents were 3.89 and 3.62.The 99% specificity S/CO limit was set as the blood donor deferral criterion.Verify test indicated that the samples, with S/CO higher than the blood donor reentry limit of reagent 1 and 2, were all from HBV infected donor.The 99% specificity S/CO limits of reagent 1 in the other three laboratories were 3.77, 3.60 and 13.42 respectively.And the 99% specificity S/CO limits of reagent 2 in the other three laboratories were 27.73, 31.75 and 1.17.Conclusion The blood donor deferral limit of HBsAg ELISA could identify the true positive blood donor, and reduce the number of blood donor, entering the reentry process.It might not suit to adopt a unified donor deferral limit in different laboratories, even using the same reagents.

Objective To determine if the cardiac index (Cl) measured with FloTrac-Vigileo system agrees with that measured with pulmonary artery catheter (PAC).Methods Forty-three ASA Ⅱ or Ⅲ patients aged 53-75 yr weighing 46-100 kg undergoing off-pump coronary artery bypass grafting were included in this study.Anesthesia was induced with midazolam,sufentanil,propofol and rocuronium and maintained with propofol,remifentanil and atracurium.One MAC sevoflurane was inhaled at breast bone splitting and closing.Cl was measured with FloTrac-Vigileo system and PAC before,and at 5,15 min of sevoflurane inhalation and recorded.All data were compared by Bland-Altman analysis and with kappa coefficient for agreement and percentage error was calculated.Results Bland-Altman comparison of FloTrac-Vigileo system and PAC:matching data of 258 measurements:Cl (2.8 ± 0.6) L·min-1 ·m-2,bias was 0.23 L·min-1 ·m-2 and limit of agreement was (-0.57,1.02) L·min-1 ·m-2,resulting in κ =0.546 and an overall percentage error of 28.6％.Conclusion Cl values obtained by FloTrac-Vigileo system agrees well with that obtained by thermodilution technique using PAC in patients undergoing off-pump coronary artery bypass grafting.

BACKGROUND:The endothelial dysfunction is the pathogenesis of arteriosclerotic disease, the quantity and function of endothelial progenitor cells are decreased within the cycle, leading to a poor capacity of neovascularizatio, the efficacy of stem celltransplantation alone is unclear, the combination of cytokines and gene-modified stem cells is the hotspot.
OBJECTIVE:To observe the effect of stromal cel-derived factor-1 on the neovascularization after endothelial progenitor cells transplantation.
METHODS:Unilateral hindlimb ischemia model was established in 20 athymic nude mice, and the mice were randomly divided into four groups:combined group (intravenous endothelial progenitor cells+intramuscular stromal cel-derived factor-1), endothelial progenitor cells group (intravenous injection of endothelial progenitor cells), stromal cel-derived factor-1 group (intramuscular injection of stromal cel-derived factor-1), and blank control group (intramuscular M199). The skin temperature of ischemic hindlimbs and survival of animals after transplantation were observed. The ratio of capil ary/skeletal muscle fiber was counted. The expression of CD31 and endothelial nitric oxide synthase were detected.
RESULTS AND CONCLUSION:The fluorescence-labeled endothelial cells were embedded in ischemic hindlimb muscles after celltransplantation. Of the 20 nude mice, two mice died. The rate of ischemic hindlimb reserving was respectively 80%, 75%, 20%and 0 in combined group, endothelial progenitor cells group, stromal cel-derived factor-1 group, and blank control group. The capil ary/muscle fiber ratio in combined group and endothelial progenitor cells group was higher than that of blank control group (P<0.01). The combined group was greater than endothelial progenitor cells group, and endothelial progenitor cells group was greater than stromal cel-derived factor-1 group (P<0.05). The capil ary density in combined group and endothelial progenitor cells group were higher than that in blank control group (P<0.01), and stromal cel-derived factor-1 group was also more than blank control group (P<0.05). The combined group was greater than endothelial progenitor cells group, and endothelial progenitor cells group was greater than stromal cel-derived factor-1 group (P<0.05). The positive rate of endothelial nitric oxide synthase was 73.33%and 53.33%in combined group and endothelial progenitor cells group respectively (P>0.05). Endothelial progenitor cells can migrate to ischemic tissues, endothelial progenitor cells transplantation can promote neovascularization, and stromal cel-derived factor-1 augments the neovascularization after celltransplantation, in which endothelial nitric oxide synthase is involved.

Objective To evaluate the effect of dexmedetomidine on left ventricular function in patients undergoing coronary artery bypass grafting (CABG) by transesophageal echocardiography (TEE).Methods The study was a prospective,randomized and placebo-control clinical trial.Eighty patients undergoing CABG with cardiopulmonary bypass (CPB) were divided into dexmedetomidine group (group D)and control group (group C) by random digits table method with 40 cases each.A loading dose of dexmedetomidine 0.5 μg/kg was injected intravenously 10 min after induction followed by infusion at 0.4 μ g/(kg· h) until the end of operation in group D,while equal volume of normal saline was given in group C.Left ventricular function was assessed by transesophageal echocardiography before the infusion of dexmedetomidine (T1),at the end of the infusion of loading dose (T2),before CPB (T3) and at the end of the operation (T4).Results Compared with those at T1,left ventricular ejection fraction and fractional area change decreased significantly [(58.0 ± 12.0)％,(60.0 ± 9.6)％ vs.(63.0 ± 8.6)％ and (46.0 ± 9.3)％,(48.0 ± 8.4)％ vs.(51.0 ± 6.7)％] (P ＜ 0.05 or ＜ 0.01),E/A ratio increased significantly (1.05 ± 0.27,1.07 ±0.31 vs.0.98 ±0.19)(P ＜0.05 or ＜0.01) and myocardial performance index (MPI) decreased significantly (0.46 ± 0.14,0.45 ± 0.12 vs.0.51 ± 0.14) (P ＜ 0.05) at T2 and T3 in group D,while stroke volume was not significantly changed (P＞ 0.05).Compared with that in group C,E/A ratio and rapid filling fraction in group D was significantly higher [1.06 ± 0.18 vs.0.97 ± 0.18,(62.0 ± 7.1)％ vs.(58.0 ± 7.3)％],and S/D ratio and MPI was significantly lower at T4(1.17 ± 0.21 vs.1.29 ± 0.22,0.43 ± 0.15 vs.0.50 ± 0.15),and there were significant differences (P ＜ 0.05).There was no difference in the parameters indicating left ventricular systolic function (P ＞ 0.05).Conclusions Dexmedetomidine restrains left ventricular systolic function in the patients undergoing CABG,but does not decrease the cardiac output,and improve relaxation dysfunction of left ventricular diastolic function.Global left ventricular function is improved by dexmedetomidine after CABG.