Wei Hongyan

GW24-e1268 A comparison of bi-level and continuous positive airway pressure noninvasive ventilation in acute cardiogenic pulmonary oedema; a systematic review

Objectives Whether bi-level positive airway pressure (BiPAP) is advantageous compared with continuous positive airway pressure (CPAP) in acute cardiogenic pulmonary oedema (ACPO) remains uncertain. The aim of the meta-analysis was to assess potential beneficial and adverse effects of CPAP compared with BiPAP in patients with ACPO. Methods Randomised controlled trials (RCTs) comparing the treatment effects of BiPAP with CPAP were identified from electronic databases and reference lists from January 1966 to July 2012. Two reviewers independently assessed study quality. Data were combined using Review Manager 4.3. Both pooled effects and 95% confidence intervals were calculated. Results Twelve RCTs with a total of 1433 ACPO patients were included. The hospital mortality (relative risk [RR] 0.86, 95% confidence interval [CI] 0.65 -1.14; P = 0.46; I 2 = 0%) and need for requiring invasive ventilation (RR 0.89, 95% CI 0.57 -1.38; P = 0.64; I 2 = 0%) were not significantly different between patients treated with CPAP and those treated with BiPAP. The occurrence of new cases of myocardial infarction (RR 0.95; 95% CI 0.77 -1.17; P = 0.53, I 2 = 0%) and length of hospital stay (RR 1.01, 95% CI -0.40 -2.41; P = 0.98; I 2 = 0%) were also not significantly different between the two groups. Conclusions There are no significant differences in clinical outcomes when comparing CPAP versus BiPAP. Based on the limited data available, there was an insignificant trend toward an increase in new onset acute myocardial infarction in patients treated with BiPAP.

GW24-e0338 The effects of activation of autophagy on the neuron injury after return of spontaneous circulation from ventricular fibrillation in Wistar rats

Objectives To investigate the effects of activation of Autophagy on cerebral injury after cardiopulmonary resuscitation (CPR) in Wistar rat. Methods First 36 healthy adult male Wistar rats were induced ventricular fibrillation (VF) by alternating current for 7 minutes and then received CPR. Before VF (0) and at 1, 2, 4, 8 and 12 hours after return of spontaneous circulation (ROSC), cerebral cortex were harvested to determine the expressions of beclin-1 and LC3II by Weston blot. Further 60 healthy adult male Wistar rats were used to observe the effects of Autophagy activator Rapamycine (Rapamycine group, 20), Autophagy inhibitor 3-Methyladenine (3-MA group, 20) and Normal saline (Control group, 20) on the expressions of beclin-1, LC3II and the formation of autophagic vacuole in the cerebral cortex after ROSC. The neurologic deficit score (NDS) was used to evaluate the neurologic function at 24, 48 and 72h respectively after ROSC. The numbers of viable neurons and apoptotic neurons in the parietal cortex were counted by H&E staining and TUNEL staining after 72h. One-way ANOVA was used for the expressions of beclin-1 and LC3II and neurons counting. Rank sum test was used for NDS. Results The expressions of beclin-1 and LC3 II were significantly lower at 2 and 4h after ROSC than the levels before VF (P < 0.05). The expressions of beclin-1 and the conversion of LC3 II in cerebral cortex at 2 and 4h after ROSC in the Rapamycine group were significantly higher than that in Control group and 3-MA group (P < 0.05). The numbers of autophagic vacuole in the Rapamycine group at 2 and 4h after ROSC were significantly higher than the Control and 3-MA group. The number of viable neurons at 72h after ROSC in the Rapamycine group was 19 ± 516 ± 4/400pixs, higher than 16 ± 4/400pixs in Control group and 15 ± 3/400pixs in 3-MA group (P < 0.05). The number of the TUNEL positive cells in the Rapamycine group was 12 ± 4/400pixs and was lower than 15 ± 6/400pixs in the Control group and 17 ± 5/400pixs in 3-MA group (P < 0.05). The NDS scores of animals in Control group and 3-MA group at 24, 48 and 72h after ROSC were inferior to Rapamycine group. Conclusions The Autophagy of neurons in the cerebral cortex was attenuated in Wistar rats after ROSC. The activation of Autophagy can decrease the number of apoptotic neurons, preserve viable neurons and improve neurologic function.

e0004 Hydrogen sulfide inhabits neurons apoptosis in rats after cardiopulmonary resuscitation

Objective To investigate the effects of hydrogen sulfide (H2S) on brain injury after cardiopulmonary resuscitation (CPR) in rats by examining neurons apoptosis. Methods The 40 male SD rats were randomly divided into experimental and control groups equally. In control group, CPR was performed with Utstein mode at 6 min after CA. On this basis, sodium hydrosulfide was administrated to the rats after restoration of spontaneous circulation in experimental group. On seventh day after CPR, neurons apoptosis was examined using terminal deoxynucleotidyl transferase mediated dUTP biotin nick end labelling (TUNEL) staining and the expression of caspase-3 was detected by the immunohistochemical strepto avidin biotinperoxidase complex (SABC) method in cortex, hippocampus CA1 region and cerebellum of the rats. Results 1. There were 12 and 10 rats completed the experiment in the experimental and control group respectively. Their fate between the two groups was no significant difference (χ2=0.404, p=0.376). 2. On seventh day after CPR, The serum concentrations of H2S was 9.12±3.17 μmol/l in the experimental group and the contrast was 3.72±1.05 μmol/l, the difference between the two groups had statistic significance (t=5.136, p=0.000). 3. Compared with the control group, the experimental groups neurons apoptosis index and the sum of integrated optical density (IOD) of caspase-3 in cortex, hippocampus CA1 region and cerebellum were obviously reduced (p<0.05). Conclusion After CPR, H2S can inhabit neurons apoptosis and its mechanism may be through caspase-3 pathway. It may play a role in the treatment of the brain injury after CA.

e0006 Effects of neotype peritoneal cooling on the injured of intestinal mucous after cardiopulmonary resuscitation in rabbits

Objective To explore whether the peritoneal cooling after cardiopulmonary resuscitation could improve the injured of intestinal mucous in rabbits. Methods 36 adult New Zealand rabbits were induced ventricular fibrillation by AC current. After the restore of spontaneous circulation (ROSC), rabbits were randomly divided into three groups according to the way of body temperature controlling, that is, nomothermia group (NT), surface cooling group (SC) and peritoneal cooling group (PC). The changing of tympanic temperature and peritoneal temperature were observed after ROSC. The animals were sacrificed by over anaesthesia after ROSC for 12 h, the end ileum was removed and fixed in formalin, the histological injured and the expression of TNF-a and VCAM-1 in ileum were observed by H.E staining and immune chemical methods. Results 12 animals in each group, 9 in group NT, 10 in group SC and 9 in group PC were successfully resuscitated; all animals were on mechanical ventilation for 2 to 4 h. 5, 6 and 8 animals in each group respectively survived to the end of the experiment. The temperatures of tympanic and peritoneal cavity of animals in group NT were maintained in normal range. The tympanic temperature of animals in group SC and PC was arrived target temperatures at 29±6.55 min and 62±8.27 min. During the stage of maintenance of hypothermia, the tympanic and peritoneal temperatures of animals in group SC were in range 33 to 35°C, while the peritoneal temperatures of animals in group PC were in range 31 to 34°C, 1 to 2°C lower than the tympanic temperature. The scores of histological injured of ileum were 1.43±0.53 in group PC, 3.4±0.55 in group NT and 3.17±0.41 in group SC. The differences among them were significantly, PC versus SC, p<0.000; PC versus NT, p<0.000; while SC versus NT, p=0.30. The expression of TNF-a in ileum was 9.98±1.79% in group NT, 5.87±1.43% in group SC and 3.78±0.53% in group PC, the differences among them were significantly. The phenomenon of the expression of VCAM-1 was little like the TNF-a, 3.78±0.53% in group PC was significantly from the 8.53±1.53% in group NT and 5.92±1.06% in group SC. Conclusion The neotype peritoneal cooling can improve the injured of ileum mucous beside quickly induce hypothermia after ROSC in rabbits.

e0005 Model of cardiac arrest in rats by transcutaneous electrical epicardium stimulation

Objective To establish a new model of Cardiac Arrest (CA) in rats by transcutaneous electrical epicardium stimulation. Methods Two acupuncture needles connected to the anode and cathode of a stimulator were transcutaneously inserted into the epicardium as electrodes. The stimulating current was steered to the epicardium and the stimulation was maintained for 3 min to induce CA. Cardiopulmonary resuscitation (CPR) was performed at 6 min after a period of nonintervention. Results The success rate of induction was 12/20 at the current intensity of 1 mA; and reached 20/20 when the current intensity was increased to 2 mA. The average time from the electrical stimulation to CA induction was 5.10 (±2.81) s. When the electrical stimulation stopped, 18/20 rats had ventricular fibrillation and 2/20 rats had pulseless electrical activity. CPR was performed for averagely 207.4 (±148.8) s. The restoration of spontaneous circulation was 20/20. The death rate within 4 h after CA was 5/20, and the 72-h survival rate was 10/20. There were only two cases of complications, a minor muscle contraction and a minor lung lobe injury. Conclusion The model of CA in rats induced by transcutaneous electrical epicardium stimulation is a stable model that requires low-intensity current and has fewer complications.