Risk Of Postoperative Bleeding Complications After Tooth Extractions In Patients On Warfarin:A Meta-analysis

Background:In 1957,Ziffer et al.gave a report about postoperative bleeding complications after tooth extractions in patients on anticoagulants for the first time.Since then,the rational use of anticoagulant drugs in the perioperative period has confused many doctors.Warfarin is one of the most commonly used oral anticoagulant for the prevention and treatment of thromboembolic diseases such as deep vein thrombosis,pulmonary embolism,stroke,myocardial infarction,rheumatic heart disease.Clinically,the prothrombin time-international normalized ratio is used to quantify the safety of patients on warfarin after surgery.In general,the doctors recommend to stop taking warfarin or reduce the dose at least 2 days before surgery,and to ensure INR?2.0 before tooth extraction operations.For high-risk embolization,physicians recommend to stop taking warfarin before surgery,and to make a heparin or low molecular weight heparin bridge therapy,which could prevent perioperative embolization.However,a large number of studies have shown that if INR ? 4.0 on the day of tooth extraction,there is no need to stop taking warfarin,reduce the dose or make a heparin bridge therapy,postoperative packing material,suture,cotton and other operations could effectively stop bleeding.Objective:Due to the high risk of withdrawal or not,high quality randomized controlled trials are of great significance.If it is safe that continuing to take the anticoagulant before tooth extraction surgery,the extraction operation for patients is a time-saving and labor-saving process.The Meta-analysis was designed to compare the risk of bleeding after tooth extractions with stopped taking or reduction of warfarin,LMWH bridge therapy,and non-stopped taking.Methods:EMbase,MEDLINE,the Cochrane Library(Issue 9,2016),CNKI,VIP,Wanfang data,China food and drug administration and the ADR supervision system of FDA were electronically searched to collect randomized controlled trials(RCT)and cohort studies about the risk of postoperative bleeding complications after tooth extractions in patients on warfarin until September 30,2016.Two reviewers independently screened literature,extracted data and assessed the risk bias of included studies.Then,Meta-analysis was performed using RevMan 5.3 software.Results:A total of 8 studies were included,involving 3 RCTs and 5 cohort studies.The results of Meta-analysis showed that: In 3 RCTs,there was no statistically significant difference in the risk of postoperative bleeding complications after tooth extractions between treatment group and control group [RR=0.86,95%CI(0.49,1.51),P=0.60].In 5 cohort studies,there was no statistically significant difference in the risk of postoperative bleeding complications after tooth extractions between exposed group and unexposed group [RR=0.67,95%CI(0.45,1.01),P=0.06].According to subgroups analysis of 5 cohort studies,there was no statistically significant difference in the risk of postoperative bleeding complications after tooth extractions between exposed group and unexposed group [RR=0.69,95%CI(0.45,1.07),P=0.10].Conclusions:Current evidence indicates that there is no statistically significant correlation beteween whether discontinue warfarin and the risk of postoperative bleeding complications after tooth extractions.Due to the limited quantity and quality of included studies,the above conclusion needs to be further verified by more high quality studies.