Objective:To evaluate the effect of blunt separation method on peripherally inserted central venous catheters.Methods:The randomized controlled trials regard to the effect of blunt separation method on peripheral central venous catheters were retrieved from CNKI, Wan fang Data Knowledge Service Platform, CQVIP, CBM, Cochrane, PubMed, EMBASE and Web of science from January 2010 to March 2021, two researchers performed quality assessments and extracted data according to Cochrane evaluation manual standards. RevMan 5. 4 software was used for statistical analysis.Results:A total of 11 randomized controlled trials were analyzed, including 1379 participants. The meta-analysis results showed that there was no statistical difference in the successful rate of one-time sheath delivery ( OR=1.62, 95% CI 0.92-2.86, P>0.05). However, patients in blunt separation group showed lower blood loss ( OR=0.24, 95% CI 0.11-0.50, P<0.05), lower the incidence of seepage at puncture site ( OR=0.18, 95% CI 0.09-0.37, P<0.05) than those in traditional skin expansion group at 24h after catheterization, and less the time of maintenance within 7 days after catheterization ( MD=-0.95, 95% CI-1.78--0.11, respectively, P<0.05). Conclusions:Blunt separation method can significantly reduce the incidence of complications and the time of catheter maintenance. Due to the limited quality of included studies, more high quality studies are needed to verify the conclusions.

Objective: To explore prognostic factors of acute paraquat poisoning (APP) , analyze the correlation between base excess (BE) and plasma concentration of paraquat (C-PQ) and discuss BE level in evalua-tion of prognosis of acute paraquat poisoning patients. Methods: We retrospectively selected 84 APP patients who admitted to Emergency Intensive Care Unit (EICU) of our hospital from 2009.9.1 to 2015.8.31.Clinical data from 84 APP patients were analyzed. BE、C-PQ、time of gastric lavagesince ingestion、time of hemoperfusion since ingestion、severity index of paraquat poisoning (SIPP) 、white blood cell (WBC) 、percentage of neutrophils (N%) 、hemoglobin (HB) 、creatinine (Cr) 、alanine aminotransferase (ALT) 、aspartate aminotransferase (AST) 、partial pressure of oxygen (PaO₂) 、partial pressure of carbon dioxide (PaCO₂) and other laboratory parameters were measured. A total of 41 patients in non-survivors died during the 30 days after admission and 43 patients in survivors survived during the 30 days. The factors of prognosis in paraquat poisoining and the role of BE in evalu-ating prognosis was analyzed, as well as the correlation between BE and C-PQ. Results: 1.Logistic regression analyses showed BE、C-PQ、ALT、AST、Cr was of prognostic significance[odds ratio (OR) of BE: 0.511, 95%CI 0.267, 0.978; C-PQ:-=0.999, 95%CI 0.999, 1.000; both P<0.05] ; 2.The area under the receiver operating characteristic curve (ROC curve) of BE、C-PQ and prognosis were 0.775、0.927 respectively, BE≤-1.7 mmol/L was the best cut-off value, the sensitivity、specificity for predicting were 82.9%、62.8%, the evaluation value was lower to C-PQ>3 273.935 ng/ml (AUC 0.927, 78.0%、95.3%) ; 3.BE negative correlated with C-PQ[-1.100 (-4.100, -0.200) , -5.900(-8.650, -2.500) , both P<0.05]. (r=-0.4, P<0.01). Conclusion These results suggest that BE may be useful for the prediction of prognosis in PQ poisoning and BE negative correlated with C-PQ.