Objective To evalute the accuracy of stroke volume variation (SVV) in monitoring blood volume in patients undergoing off-pump coronary artery bypass grafting.Methods Twenty-one ASA Ⅱ or Ⅲ patients of both sexes aged 44-77 yr undergoing off-pump coronary artery bypass grafting were enrolled in this study.Anesthesia was induced with midazolam,etomidate,fentanyl,rocuronium and dolicaine and maintained with target-controlled infusion of propofol,infusion of remifentanil,intermittent iv injetion of atracurium and inhalation of sevoflurane.The patients were mechanically ventilated (VT 8 ml/kg,RR 12 bpm,I:E 1:2,PEEP 0,FiO2 80％ ).PEr CO2 was maintained at 35-44 mm Hg.Radial artery was cannulated and connected to FloTrac pressure transducer and Vigileo monitor.6％ hydroxyethyl starch 130/0.4 sodium chloride solution 7 ml/kg was infused at a rate of 0.25 ml· kg- 1 1· min- 1 at 5 min of haemodynamics stabilization after pericardiotomy (T1).HR,MAP,CVP,systemic vascular resistance (SVR),systemic vascular nesistance index (SVRI),SVV,stroke volume index (SVI)and CI were recorded at T1 and at 10 min after loading dose (T2).The change rate of HR(△HR),MAP(△MAP),CVP(△CVP),SVR(△SVR),SVV(△SVV),SVI(△SVI) and CI(△CI) were calculated.△SVI≥25％ was considered effective volume expansion.The ROC curves for HR,MAP,CVP,SVR and SVV in determining the volume expansion efficacy were plotted.The area under the curves and 95 ％ confidence interval were calculated.Results Compared with T1,CVP,SVI,CO and CI were significantly increased,SVRI and SVV decreased at T2 (P ＜ 0.01).There was no significant difference in MAP and HR between T1 and T2(P ＞0.05).△SVI was negatively correlated with △HR and △SVR ( r =- 0.737,r =- 0.480,P ＜ 0.05).△SVI was not correlated with △CVP,△MAP and( P ＞ 0.05).The change in SVI was determined by SVV 8.8％ (sensitivity =52.6％,specificity =100.0％ ).The area under the curve for SVV and 95％ confidence interval were 0.579(0.346-0.812).Conclusion SVV can not be used to accuratelymonitor the changes in blood volume in patients undergoing off-pump coronary artery bypass grafting.

Objective To investigate the predictive efficiency of combined uterine artery hemo-dynamic parameters and oxidative stress indicators in early pregnancy on hypertensive diseases in pregnancy(HDP).Methods A total of 90 HDP patients(case group)and 30 healthy pregnant women(control group)as research subjects.The case group included 30 patients with pregnancy-in-duced hypertension,30 patients with preeclampsia,and 30 patients with severe preeclampsia,respec-tively,and were divided into pregnancy-induced hypertension group,preeclampsia group,and severe preeclampsia group.Serum levels of reactive oxygen species(ROS),superoxide dismutase(SOD),heme oxygenase-1(HO-1),glutathione peroxidase(GSH-PX),malondialdehyde(MDA),and uterine artery hemodynamic parameters were compared between the two groups in early pregnancy(8 weeks to 13 weeks plus 6 days).The receiver operating characteristic(ROC)curve was used to evaluate the predictive efficiency of relevant indicators for HDP.Results The serum levels of SOD and GSH-PX were lower in the case group than that in the control group,and the serum level of MDA and the uterine artery pulsatility index(PI)were higher in the case group than that in the control group(P＜0.05).The serum levels of SOD and GSH-PX gradually decreased,and the serum levels of MDA and PI gradu-ally increased in the pregnancy-induced hypertension group,the preeclampsia group,and the severe preeclampsia group(P＜0.05).The ROC curve showed that the combination of SOD,GSH-PX,MDA,and PI in early pregnancy had a higher predictive efficiency for HDP,with an area under the curve of 0.824,a sensitivity of 81.1％,and a specificity of 76.7％.Conclusion Patients with HDP have changes in oxidative stress indicators and uterine artery hemodynamic parameters in early preg-nancy,and there are differences among patients with different disease severities.The combined de-tection of SOD,GSH-PX,MDA,and PI in early pregnancy can help predict HDP.

Objective To investigate the predictive efficiency of combined uterine artery hemo-dynamic parameters and oxidative stress indicators in early pregnancy on hypertensive diseases in pregnancy(HDP).Methods A total of 90 HDP patients(case group)and 30 healthy pregnant women(control group)as research subjects.The case group included 30 patients with pregnancy-in-duced hypertension,30 patients with preeclampsia,and 30 patients with severe preeclampsia,respec-tively,and were divided into pregnancy-induced hypertension group,preeclampsia group,and severe preeclampsia group.Serum levels of reactive oxygen species(ROS),superoxide dismutase(SOD),heme oxygenase-1(HO-1),glutathione peroxidase(GSH-PX),malondialdehyde(MDA),and uterine artery hemodynamic parameters were compared between the two groups in early pregnancy(8 weeks to 13 weeks plus 6 days).The receiver operating characteristic(ROC)curve was used to evaluate the predictive efficiency of relevant indicators for HDP.Results The serum levels of SOD and GSH-PX were lower in the case group than that in the control group,and the serum level of MDA and the uterine artery pulsatility index(PI)were higher in the case group than that in the control group(P＜0.05).The serum levels of SOD and GSH-PX gradually decreased,and the serum levels of MDA and PI gradu-ally increased in the pregnancy-induced hypertension group,the preeclampsia group,and the severe preeclampsia group(P＜0.05).The ROC curve showed that the combination of SOD,GSH-PX,MDA,and PI in early pregnancy had a higher predictive efficiency for HDP,with an area under the curve of 0.824,a sensitivity of 81.1％,and a specificity of 76.7％.Conclusion Patients with HDP have changes in oxidative stress indicators and uterine artery hemodynamic parameters in early preg-nancy,and there are differences among patients with different disease severities.The combined de-tection of SOD,GSH-PX,MDA,and PI in early pregnancy can help predict HDP.

Objective:To evaluate the outcome of the patients receiving dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) delivered by first-responders who witnessed the out-of-hospital cardiac arrest (OHCA) before the Emergency Medical Service (EMS) arrived.Methods:We performed a search of the relevant literature exploring major scientific databases. We assessed the quality of the included cohort study according to the Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0. Meta-analysis was performed on three outcome indicators (recovery of spontaneous circulation survival to hospital discharge and survival with favourable neurologic outcome) using the Revman5.3 software.Results:A total of 21 studies with 349 822 patients were selected for the meta-analysis, including 182 125 patients in the DA-CPR group and 167 697 in the CPR-only group. The meta-analysis showed no significant difference between the DA-CPR and CPR-only groups in ROSC [ RR=1.10, 95% confidence interval ( CI): 0.94-1.29, P=0.24], survival to hospital discharge ( RR=1.10, 95% CI: 0.90-1.34, P=0.34) and survival with favourable neurologic outcome ( RR=1.01, 95% CI: 0.79-1.28, P=0.97) of the patients in America, Japan and Korea. However, there was a significant difference between the DA-CPR and the CPR-only groups in ROSC ( RR=2.61, 95% CI:1.53-4.46, P=0.0005), survival to hospital discharge( RR=6.08, 95% CI: 1.84-20.04, P=0.003), and survival with favourable neurologic outcome( RR=9.76, 95% CI: 1.87-51.02, P=0.007) of the patients in China. Conclusions:The overall effect of DA-CPR is significantly different for each country. In detail, DA-CPR offers a survival advantage (Return of spontaneous circulation, survival to hospital discharge and survival with favourable neurologic outcome) over CPR alone in China but no advantage in developed countries.