Perioperative Coagulation Function Changes In High-risk Patients With Lower Extremity Venous Thromboembolism And Early Anticoagulant Drugs To Prevent Thrombosis

Objective: To investigate the changes of coagulation function in patients with high risk of venous thromboembolism and to compare and analyze the efficacy and safety of rivaroxaban and low molecular weight heparin in the prevention of deep venous thrombosis of lower extremity during perioperative period of general surgery.Methods: A total of 59 patients who received various general anesthesia operations in the Department of General Surgery of Baotou Central Hospital from December 2019 to January2021 were collected.According to Caprini score,the patients were divided into medium risk group(group A)and high risk group(group B,C).Group A had 17 patients,who were given perioperative physical measures to prevent thrombosis;Group B and C had 21 patients,respectively,who were given low molecular weight heparin and rivaroxaban anticoagulant therapy.Routine blood and coagulation indexes were collected from all patients on the day of admission,the first day after surgery and the seventh day after surgery.Coagulation parameters were compared among the groups,and the occurrence of postoperative DVT and bleeding events were observed among the groups.Results :(1)Comparison of blood indexes between groups: D-dimer(D-D)in the anticoagulant treatment group on the first day after surgery was significantly higher than that in the non-anticoagulant treatment group,with statistical significance(P<0.05).There was no statistical significance in the other indicators among the groups(P > 0.05).(2)Dynamic change trend of blood indexes: FIB and D-D after anticoagulant therapy were significantly higher than those before surgery,and Thrombin Time(TT)were significantly lower than those before surgery in the non-anticoagulant group,with statistical significance(P<0.05).Hemoglobin(Hb)and RBC in the anticoagulant group were significantly lower after surgery than before surgery,with statistical significance(P<0.05).There was no statistical significance in pairwise comparison among other time points(P > 0.05).With the treatment,D-D in the anticoagulant treatment group showed a downward trend,while there was no significant change in the non-anticoagulant treatment group,and the difference was not statistically significant(P > 0.05).(3)In the identification of high risk thrombus,the Area Under the Curve(AUC)of FIB was 0.668,95%CI(0.450-0.885).When the sensitivity was90.4% and the specificity was 42.9%,the maximum diagnostic index was 0.333,and the corresponding diagnostic cut-off point was 3.305g/L.The AUC of D-D was 0.644,95%CI(0.401-0.888),and the maximum diagnostic index was 0.319 when the sensitivity was 85.7%and the specificity was 46.2%,and the corresponding diagnostic cut-off point was 4.485g/L.The combined AUC of Prothrombin Time(PT),Activated Partial Prothrombin Time(APTT),TT,D-D,Platelet(PLT)and FIB was 0.834,95%CI(0.666-1.000),and the sensitivity and specificity were 71.4% and 92.3% respectively.Other indicators were not effective in assessing the high risk of thrombus.(4)Incidence of DVT: DVT occurred in 7 of 59 patients,all of which were peripheral type.The incidence of DVT was 11.8% in group A,11.9% in group B,and 9.5% in group C.There was no significant difference in the incidence of DVT among the three groups(P > 0.05).No symptomatic PE was found in all three groups.There was no DVT in the postoperative follow-up for one month.(5)Incentive rate of bleeding: one patient in all the patients,the rivaroxaban anticoagulant group,suffered from bleeding of digestive tract,while the other two groups did not have bleeding events.Conclusion:1.Patients with high risk of VTE in general surgery showed significantly more coagulation and fibrinolytic activation state than those with medium risk after surgery.Anticoagulant therapy can improve coagulation and fibrinolytic activation state and reduce the risk of VTE in patients.2.The combination of PT,APTT,TT,FIB,D-D and PLT has the best diagnostic efficacy for DVT of lower extremity,while D-D and FIB have better diagnostic efficacy for DVT of lower extremity.3.Rivaroxaban and LMWH are equally effective in preventing venous thrombosis during perioperative period in general surgery department,and the safety of rivaroxaban in preventing thrombosis still needs further large-scale clinical research.