Comparison of extracorporeal and conventional cardiopulmonary resuscitation: A meta-analysis of 2 260 patients with cardiac arrest.

BACKGROUND: This meta-analysis aimed to determine whether extracorporeal cardiopulmonary resuscitation (ECPR), compared with conventional cardiopulmonary resuscitation (CCPR), improves outcomes in adult patients with cardiac arrest (CA). DATA RESOURCES: PubMed, EMBASE, Web of Science, and China Biological Medicine Database were searched for relevant articles. The baseline information and outcome data (survival, good neurological outcome at discharge, at 3-6 months, and at 1 year after CA) were collected and extracted by two authors. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using Review Manager 5.3. RESULTS: In six studies 2 260 patients were enrolled to study the survival rate to discharge and long-term neurological outcome published since 2000. A significant effect of ECPR was observed on survival rate to discharge compared to CCPR in CA patients (RR 2.37, 95%CI 1.63-3.45, P<0.001), and patients who underwent ECPR had a better long-term neurological outcome than those who received CCPR (RR 2.79, 95%CI 1.96-3.97, P<0.001). In subgroup analysis, there was a significant difference in survival to discharge favoring ECPR over CCPR group in OHCA patients (RR 2.69, 95%CI 1.48-4.91, P=0.001). However, no significant difference was found in IHCA patients (RR 1.84, 95%CI 0.91-3.73, P=0.09). CONCLUSION: ECPR showed a beneficial effect on survival rate to discharge and long-term neurological outcome over CCPR in adult patients with CA.

Performance of hybrid constructed wetland systems for treating septic tank effluent.

The integrated wetland systems were constructed by combining horizontal-flow and vertical-flow bed, and their purification efficiencies for septic tank effluent were detected when the hydraulic retention time (HRT) was 1 d, 3 d, 5 d under different seasons. The results showed that the removal efficiencies of the organics, phosphorus were steady in the hybrid systems, but the removal efficiency of total nitrogen was not steady due to high total nitrogen concentration in the septic tank effluent. The average removal rates of COD (chemical oxygen demand) were 89%, 87%, 83%, and 86% in summer, autumn, winter and spring, respectively, and it was up to 88%, 85%, 73%, and 74% for BOD5 (5 d biochemical oxygen demand) removal rate in four seasons. The average removal rates of TP (total phosphorous) could reach up to 97%, 98%, 95%, 98% in four seasons, but the removal rate of TN (total nitrogen) was very low. The results of this study also indicated that the capability of purification was the worst in winter. Cultivating with plants could improve the treated effluent quality from the hybrid systems. The results of the operation of the horizontal-flow and vertical-flow cells (hybrid systems) showed that the removal efficiencies of the organics, TP and TN in horizontal-flow and vertical-flow cells were improved significantly with the extension of HRT under the same season. The removal rate of 3 d HRT was obviously higher than that of 1 d HRT, and the removal rate of 5 d HRT was better than that of 3 d HRT, but the removal efficiency was not very obvious with the increment of HRT. Therefore, 3 d HRT might be recommended in the actual operation of the hybrid systems for economic and technical reasons.

[Metal removal from contaminated soil by co-planting phytoextraction and soil washing].

Combining the different soil remediation technologies can overcome the shortcoming of a single technique, for example, the combination of phyto-extraction with chemical washing can enhance the phytoextraction and build up an effective technology. In a pot experiment, the co-crop of Sedum alfredii and Zea mays was conducted, chemical washing was also applied with different mixtures of chelators (MC). Metals amounts washed by leaching, the uptake of metals by plants and the metals contents remained in soils were determined. Results showed that the co-crop combining with 10 mmol x L(-1) MC washing removed the highest amount of Zn and Cd,and after 2 crops, the removal rates reached 6.0% and 40.46% of the soil total metal respectively for Zn and Cd, which were higher than those for the only co-planting. Soil analysis showed that the two successive co-crops with MC washings decreased soil Cd,Zn and Pb by 27.8% - 44.6%,12.6% -16.5% and 3.6% - 5.7%, respectively. Chemical washing with 50 mmol x L(-1) MC affected the growth of S. alfredii and resulted in higher metal contents in thereafter leachate water than the other less concentrated washing agents. EDDS ([S, S]-ethylenediaminedisuccinic acid) enhanced the phytoextraction of Cd and Zn but did not effectively wash Pb. Zn and Cd removal mainly depended on phytoextraction while Pb removal relied on MC-washing in this combined technology, by which the multi-metals contamination problem could be resolved.