Preventive Effect Of Anticoagulation Timing On Perioperative DVT In Elderly Patients With Hip Fracture And Analysis Of Risk Factors

Objective: 1.To explore the influence of anticoagulation timing on the incidence of perioperative deep venous thrombosis in elderly patients with hip fracture and how to prevent the formation of perioperative deep venous thrombosis in elderly patients with hip fracture to the greatest extent,so as to reduce the mortality rate;2.To analyze the risk factors of perioperative deep venous thrombosis in elderly patients with hip fracture.Methods: A retrospective analysis was made of the data of 179 elderly patients with hip fracture admitted to the lower extremity trauma and orthopaedics ward of Xi’an Honghui Hospital from July 2017 to December 2018.There were 78 males and 103 females,aged 60-95 years,with an average age of 79.5 years.There were 63 femoral neck fractures and 116 femoral intertrochanteric fractures.119 cases were treated with internal fixation and 60 cases with hip replacement.All patients underwent venous ultrasound,blood routine and coagulation examination before and after operation.Due to the continuous renewal of the concept of thrombosis prevention,individual differences in clinical practice and social factors,not all patients received regular preventive anticoagulation therapy immediately after injury or admission.However,all patients in this study stopped taking drugs 12 hours before operation and continued using drugs 8-12 hours after operation.For research purposes 1,we divided patients into three groups according to the time from injury to admission.74 patients in anticoagulation group 1(time from injury to admission is less than 24 hours),36 patients in anticoagulation group 2(time from injury to admission is less than 48 hours),and 69 patients in anticoagulation group 3(time from injury to admission is less than 12 hours before admission)were evaluated by statistical analysis.The incidence of deep venous thrombosis in perioperative period was compared among the three groups,and then the difference analysis was used to compare the two groups.P < 0.05 showed that there was significant difference.For research purpose 2,according to the results of venous ultrasonography of lower limbs before and after operation,patients with thrombosis during perioperative period were included in thrombosis group,and patients without thrombosis were included in non-thrombosis group.The risk factors of thrombosis group were screened by univariate analysis of age,sex,fracture type,operation method and medical diseases,and then multivariate factors were used.Logistic regression analysis identified the main independent risk factors,P < 0.05 that the difference was statistically significant.Results: 1.Of all the patients,84 had deep venous thrombosis(DVT)during the perioperative period,with an incidence of 46.93%.2.There were 20 cases of deep venous thrombosis(DVT)in perioperative period in anticoagulant group 1(27.03%);17 cases of DVT in anticoagulant group 2(47.22%)and 47 cases of DVT in anticoagulant group 3(68.12%).3.Comparison of perioperative deep venous thrombosis in three anticoagulant groups(test statistics = 24.206,P < 0.001).The results showed that there was significant difference in the overall deep venous thrombosis in three anticoagulant groups during perioperative period.The comparison among the three groups: comparison between anticoagulant group 1 and anticoagulant group 2,comparison between anticoagulant group 1 and anticoagulant group 3,comparison between anticoagulant group 2 and anticoagulant group 3,the statistical results showed that the ratio between the three groups was significant.Compared with the incidence of DVT,there were significant differences(P < 0.05),that is,the incidence of DVT in three groups showed an increasing trend during the perioperative period.4.Age(OR = 1.366,95% CI: 1.229-1.518),coronary atherosclerotic heart disease(OR = 6.606,95% CI: 2.468-17.681)and post-operative D-dimer(OR = 1.270,95% CI: 1.103-1.463)are independent risk factors for perioperative DVT in elderly hip fracture patients.Conclusion: 1.The incidence of DVT in elderly patients with hip fracture is still high even if thrombosis prevention measures are actively adopted during the perioperative period.2.The incidence of perioperative DVT was different in the three anticoagulation groups.The incidence of perioperative DVT was increasing in the three groups: anticoagulation group 1(the anticoagulation time from injury to admission was less than 24 hours),anticoagulation group 2(24 hours < the anticoagulation time from injury to admission was less than 48 hours),anticoagulation group 3(48 hours < the anticoagulation time from injury to admission < 12 hours before admission).That is to say,the incidence of perioperative DVT was increasing in the three groups.The earlier the time of post-anticoagulation,the lower the incidence of perioperative thrombosis.3.Regular prophylactic anticoagulation therapy can effectively reduce the incidence of perioperative DVT in elderly patients with hip fracture.4.Age,coronary atherosclerotic heart disease and post-operative D-dimer are independent risk factors for perioperative DVT in elderly patients with hip fracture.