Meta Analysis Of The Effects Of Preoperative Anemia And Blood Transfusion On Patients With Colorectal Cancer

Objectives Through Meta analysis,the existing literatures at home and abroad related to postoperative complications,long-term survival rate and treatment of anemia in patients with colorectal cancer were analyzed,in order to clarify the harmfulness and importance of preoperative anemia,provide evidence for the necessity and method choice of correcting preoperative anemia,and provide new ideas for strengthening perioperative treatment and improving prognosis of patients with colorectal cancer.Methods 8 databases were searched,including 4 Chinese databases(CBM,CNKI,VIP,Wan fang)and 4 English databases(Web of Science,Cochrane library,Pub Med,Embase).The search period of the database was limited to November 2020,and the related literatures about preoperative anemia of colorectal cancer were obtained.Set up inclusion and exclusion criteria and include qualified literature accordingly,all of which are cohort studies.Document management is carried out through Endnote X9.According to the different types of literature studies,different quality evaluation methods need to be selected,and the cohort study was conducted with the Newcastle-Ottawa scale.After the relevant data were identified and extracted from the literature,the relevant software was used for Meta analysis(Review Manager5.3).According to the heterogeneity of the data,different models need to be used for analysis.Using the fixed effect model requires relatively small data heterogeneity,that is,P≥0.1,I~2<50%;otherwise,the random effect model must be selected,and the results of the modified model are relatively conservative,and if the conditions are consistent,through sensitivity analysis to find the source of heterogeneity.Funnel plots can be used to evaluate literature publication bias.There are the data collected in this experiment:the incidence of postoperative complications(including anastomotic fistula and infectious complications)and 5-year survival of patients with colorectal cancer complicated with anemia before operation;the 5-year survival of anemic patients treated by blood transfusion and the demand for blood transfusion after iron supplementation.Results 52 cohort studies were included.The results are as follows:Preoperative anemia increases the incidence of postoperative complications,infectious complications and anastomotic leakage.Preoperative anemia can lead to a decrease in the overall 5-year survival rate of patients.Perioperative blood transfusion can lead to a decrease in 5-year overall survival rate in patients with colorectal cancer.Intravenous iron in the treatment of anemia does not reduce the perioperative demand for blood transfusion in patients with colorectal cancer.Conclusions Preoperative anemia increases the incidence of postoperative compliations,infectious complications and anastomotic leakage and reduce the overall 5-years survival rate.It is necessary to treat anemia in the preoperative period.Perioperative blood transfusion can reduce the 5-years overall survival probability of patients with colorectal cancer,and the use of blood products should be avoided when treating anemia.Oral or intravenous iron supplementation has no significant difference in reducing the demand for perioperative blood transfusion,which can be selected as appropriate.Figure 20;Table 12;Reference 216...