Objective To establish a stabile normal model of cardiac arrest (CA) by programmed electrical stimulation(PES). Method Eighteen healthy domestic swine were anesthesiased with propofol. Ventrieular fibril-lation (VF) was induced by PES through right ventricle after tracheal intubation. The PES mode is S1S2 (300/200 ms), 40 V, and-10 ms step length. Results VF was successfully induced in 16 of eighteen swine with the method of PES. The extent of coupling interval of S1S2 was between 110 and 190 ms (168±23) ms. VF occurred in 2 swines when S1S1 (350 ms) stimulus was used to decide if the electrede was placed in right ventricle. All the swine were successfully defibrillated after 3 minutes of untreated VF. Conclusions This swine model of VF is easy to repeat and orerase, and has little injury on the heart. Therefore PES is a good method to make animal car-diac arrest model.

Objective To evaluate the infection rate and influencing factors of Hepatitis E Virus among different occupational population in nanjiang region of Xinjiang. Methods A cross-sectional survey was carried out in occupational population and non-occupational population having a close contact with livertock. Serum IgG antibodies against hepatitis E virus was tested by indirect enzyme-linked immunosorbent assay , and logistic regression model was used to analyze the risk factors of HEV infection. Results The result showed that the total positive rate was 51.88% and 317 out of 611 subjects were anti-HEV IgG positive. Non-occupational population had the lowest positive rate (35.90%), followed by the stock man of intensive nursery (24.14%), stock man of scattered nursery (76.00%), livestock and meat salesperson (79.37%) and slaughterman (81.53%). Multivariate logistic regression analysis showed that close contact with livestock , eating out and without frequent hand washing increased the risk of HEV infection . And HEV infection rate decreased in the population with professional training. Conclusion It is noticeable that promoting good health habits and cutting off animal-contact transmission are effective measures for the prevention of hepatitis E.

Objective:To investigate the infection status and influencing factors of hepatitis E virus infection among different occupational populations in Xinjiang region,and to provide a available evidence for control of hepatitis E.Methods:A randomly sampling survey was carried out in the population of public health practitioners, the serum IgG antibodies against hepatitis E virus in 1 720 samples were tested by indirect enzyme-linked immunosorbent assay,and the experimental data was analyzed with SPSS 19.0 software;the differences of infection rates between genders,ages and occupations were analyzed.Results:Among 1 720 subjects,440 persons were anti-HEV IgG positive,and the total positive rate was 25.58%;the positive rate of males (27.99%)was higher than that of females (23.35%),and the IgG positive rate was increased along with the age;there were significant differences of the anti-HEV-IgG antibody positive rates between the populations with different ages (χ2 =118.262, P = 0.000 ). There was a statistically significant difference of infection rate of hepatitis E between different occupational populations (χ2 = 98.262,P = 0.000),the slaughterman had the highest positive rate (81.53%), followed by the livestock and meat salesperson (79.37%),food service population (30%),supermarket population (11.21%)and others (9.03%).Conclusion:The hepatitis E infection rate is high among the public health practitioners in Xinjiang region,and occupation,age and gender are the major influencing factors of hepatitis E infection rate.

Objective Two different transthoracic impedances were made with an adjustable impedance instrument to compare the success rate of defibrillation,heart and skin damage in a porcine model.Methods A total of sixteen pigs were randomly (random number) divided into two groups:low impedance group (about 50 Ω,n =8) and high impedance group (about 100 Ω,n =8).Defibrillation (recommended 150 J) was first attempted at 15 s after induction of ventricular fibrillation (VF).If spontaneous circulation was not recovered,2-minute chest compression and subsequent defibrillation attempts (maximum 200 J) were attempted.Model animal kept stabilization for 30 min after return of spontaneous circulation before induction of the next episode of VF,which was induced five episodes in each pig.Results In the low impedance group,VF was induced 39 times,39 of 43 attempted defibrillations were successful.In the high impedance group,VF was induced 40 times,40 of 70 attempted defibrillations were successful.The current and success rate of the first defibrillation were (34.9 ±3.2) A and 94.9％ respectively in the low impedance group,while those of the high impedance group were (19.1 ±2.1) A and 50％ respectively (both P ＜ 0.05).There were no significant differences in skin damage between two groups,but myocardial injury was lighter in the high impedance group.Conclusions Success rate of the first defibrillation with recommend 150 J obviously decreases with the increase of transthoracic impedance.The main factor of myocardial injury is current instead of the numbers of defibrillation.

Objective Amiodarone was diluted to release the side effect of hypotension in clinic, but this maybe unsuitable during cardiopulmonary resuscitation (CPR). This study was designed to observe the effects of undiluted amiodarone, diluted amiodarone, and CPR alone on ventricular fibrillation (VF) in a pig model. MethodsVF was induced in 21 pigs. The animals were randomly (random mumber) divided into 3 groups after VF 3 min.① CPR group ( n= 7): standard CPR; ② undiluted amiodarone group ( n= 7): undiluted amiodarone (5 mg/kg)bolus within 3 s, then 20 mL saline flush into the peripheral vein, CPR was started after observed 30 s; ③ diluted amiodarone group ( n = 7): amiodarone was dissolved in 20 mL saline and bolus with 30 s. Defibrillation was attempted at VF 5 min. Results The restoration of spontaneous circulation (ROSC) of CPR and undiluted amiodarone groups were higher than diluted group (85.7％ vs. 71.4％ vs. 42.9％), but the differences were not significant (all P ＞0.05). The defibrillation energy and timesof CPR group were higher than that of undiluted amiodarone (P= 0.009) and diluted group ( P = 0. 170). The mean arterial pressure of undiluted amiodarone were lower than diluted and CPR groups at ROSC 10 min (all P ＜0.05), but the differences of undiluted and diluted groups were not significant after ROSC 0.5 h. Conclusions In this study, undiluted amiodaronecan effectively reduced the defibrillation times and energy. Although diluted amiodaronecan release the side effect of hypotension which was transient, it didn't significantly improved cardiac electric activity and delayed to start CPR.

Objective To reveal the changes of catecholamine and lactate levels in myocardial interstitial fluid during cardiopulmonary resuscitation in order to prove the protective effects of sildenafil pretreatment on post-resuscitation myocardial function in swine model of ventricular fibrillation (VF).Methods Twenty-four swine were randomly (random number) divided into three groups:saline group,sildenafil group and shame operation group.Sildenafil in dose of 0.5 mg/kg dissolved in 40 mL of saline was given to swine once intraperitoneally 40 min prior to VF in sildenafil group.The equivalent volume of saline (0.9％ NaC1) alone was administered instead in saline groups.There was no treatment in shame operation group.After ventricular fibrillation untreated for 8 min,open-chest cardiopulmonary resuscitation was initiated.The hemodynamic variables were recorded at baseline,4 min,1 h and 6 h after restoration of spontaneous circulation (ROSC).The interstitial fluid from the left ventricle wall was collected by using the microdialysis tubes at given intervals,in which the levels of dopamine,norepinephrine,epinephrine,and lactate were measured.The samples for pathological examination were taken at 24 hours after ROSC.Results The levels of catecholamine and lactate in the sildenafil group were lower than those in saline group at all different intervals (P ＜ 0.05 or P ＜ 0.01).The cumulative defibrillation energy was lower in the sildenafil group than that in the saline group (P ＜ 0.05).The hemodynamic changes and myocardial histological damage in sildenafil group were milder than those in saline group (P ＜ 0.05).The pathologic changes of myocardium and mitochondria in saline group were more severe than those in sildenafil group.Conclusions Sildenafil pretreatment prior to VF can effectively reduce endogenous catecholamine secretion and lactate levels in myocardial tissue,protecting the myocardium and improving post-resuscitation myocardial function.

Objective To evaluate the effects of ulinastatin (UTI) on brain protection after cardiopulmonary resuscitation in a porcine model.Methods A total of 20 female swine were induced to make ventricular fibrillation (VF) by programmed stimulation method,and CPR was stared after 8 mins after VF.Swine after ROSC (return of spontaneous circulation) were randomly (random number) divided into two groups,namely UTI group and control group.In UTI group,UTI was administered slowly in a dose of 100 000 U dissolved in 5 ml saline immediately after resuscitation and then given every 3 h until 24 h after CPR (UTI not given at the time of 24 h) ; and 5 ml saline was used instead in control group.Venous blood samples were taken separately before VF,immediate after resuscitation and 3 h,12 h and 24 h after ROSC for detecting levels of TNF-o and IL-1β.Cerebral performance category (CPC) scores were assessed 24 h after ROSC,and subsequently the swine were sacrificed to get brain specimens for histopathological and ultrastructural examination under ordinary light microscope.Results Fifteen of twenty domestic swine were successfully rescued 8 mins after ventricular fibrillation.Swine of UTI group (n =8) and control group (n =7) were all survived over 24 h.Both TNF-α and IL-1β levels were significantly lower in UTI group than those in control group at intervals of 3 h,12 h and 24 h after ROSC (P ＜0.05).Twenty-four hours after ROSC,CPC scores of swine were higher in UTI group than those in control group (P ＜ 0.05).The brain injury 24 h after ROSC was significantly attenuated in UTI group than that in control group.Conclusions UTI can reduce the injury of brain tissue and improve the recovery of cerebral function after CPR.

ObjectiveTo study the role of catecholamine in genesis of myocardium injury after organophosphorus poisoning (OP) in order to elucidate the underlying mechanisms of OP-induced cardiotoxicity.Methods Of 92 patients with severe acute dichlorvos poisoning,41 were consecutively enrolled for study and followed up for three months. The levels of serum creatine kinase isoenzyme myocardium (CK-MB),cardiac troponin Ⅰ (cTnI),acetylcholinesterase (AChE),acetylcholine (Ach),epinephrine and norepinephrine were assayed on the 1st,3rd and 5th days after admission and on the day of discharge.Electrocardiography was recorded every day after admission.ResultsOf them,37 (90.2％ )patients survived and four ( 9.8％ ) patients died during treatment.Sinus tachycardia was found in 37 (90.2％ ) patients and ST-T changes in 33 (80.4％ ) patients.CK-MB and cTnI levels peaked 3 days after admission,and then decreased to normal levels.Serum Ach,epinephrine and norepinephrine peaked on the 1st day after admission and then decreased.ConclusionsSevere acute dichlorvos poisoning is associated with myocardial dysfunction likely caused by increase in catecholamine levels.

AIM:To explore the effect of atorvastatin on the function of carotid artery after adventitia removal in SHR.METHODS:16-week old male SHR(n=36) with left carotid artery adventitia removed were randomly divided into 3 groups(n=12,each):SHR control group,atorvastatin group,valsartan group and the half rats of each group were put to death at the 4th and 8th weeks respectively.The systolic blood pressure(SBP) was assessed before and after treatment with atorvastatin every 2 weeks.The velocity of carotid artery was detected by electromagnetic rheometer while vasotension changes to NE was measured using a force transducer connected with a polygraph.RESULTS:Compared with SHR control group,the SBP of atorvastatin group began declining at the 4th week,and was reduced significantly at the 6th and 8th weeks(P0.05).Vasotension to NE of carotid artery was reduced significantly after adventitia removal(P

Objective Gasp was defined as a pathology respiration during cardiac arrest. This study was to investigate its effect on hemodynamics during CPR. Method Twelve domestic pigs, weighening (30 ± 1) kg,were anaesthetized. After tracheal intubation and mechanical ventilation, continuous respiratory variables were recorded. An artery catheter was inserted for reference blood samples and measuring aortic artery pressure (AOP).Right atrial pressure (RAP) and cardiac output (CO) were detected by Swan-Ganz catheter. Ventricular fibrillation (VF) was induced by programmed electrical stimulation instruments. After 4 minutes untreated VF, standard 30:2 CPR was done for 12 minutes and the parameters were recorded. Results pH, PaCO2 and lactic acid increased and PaO2 decreased progressively during CPR, whereas PaO2 was up to 50mmHg during the whole protocol. Gasps were observed in 10 animals, but weaken gradually; the left 2 animals with no gasp did not restore of spontaneous circulation (ROSC). Standard CPR could produce passive ventilation more than dead space (VD), but its tidal volume decreased gradually, which led to the percentage of rescue ventilation increased progressively. Positive correlations were found between CO, coronary perfusion pressure (CPP) and minute ventilation of gasps (MVg) (r was 0.736 and 0.721 respectively, both P ＜0.01); negative correlation were found between RAP and MVg (r= -0. 744, P ＜ 0.01). Conclusions Standard CPR could maintain 12 minutes oxygenation of body; compressions could produce enough passive ventilation more than VD; gasps were benefit to ROSC by increasing CO, CPP and decreasing RAP.