Clinical Study On The Occurrence And Outcome Of Deep Vein Thrombosis In Patients With Lower Extremity Fracture Within 1 Month After Surgery

Objective: 1.To investigate the occurrence and outcome of deep vein thrombosis(DVT)in patients with lower limb fracture within 1 month after surgery.2.Independent risk factors for DVT occurrence and incomplete dissolution within 1month after surgery were analyzed.Methods: The clinical data of 730 patients with lower limb fracture admitted to the Affiliated Honghui Hospital of Xi ’an Jiaotong University(Bone Trauma Hospital)from September 2018 to December 2020 were retrospectively analyzed.During the period of hospitalization,the patients were rechecked the venous ultrasound of both lower limbs preoperative,postoperative and before discharge,After discharge from hospital(1 month after surgery),the outpatient department rechecked the venous ultrasound of both lower limbs.The occurrence and outcome of DVT were observed and recorded.All patients in the study received intravenous blood tests for D-dimer during hospitalization and 1 month after surgery The new DVT was observed in patients who did not develop DVT during hospitalization,According to the results of ultrasound review,they were divided into DVT group and non-DVT group;The outcome of DVT was observed in patients with DVT during hospitalization,According to the results of ultrasonic review,they were divided into dissolving and dissipating group and undissolving and dissipating group.The differences of patients’ age,gender,D-dimer results,operative duration,postoperative anticoagulation duration,fracture site,body mass index(BMI)and other related factors,Whether functional exercise,whether multiple fractures,whether combined with medical diseaseswere analyzed and compared.The variables with statistical significance(P <0.05)in the above differences were further analyzed by multivariate Logistic regression.Risk factors for the occurrence and outcome of DVT after discharge(1month after surgery)were analyzed.Results: A total of 1150 patients with lower extremity fractures were included in this study,of whom 420 patients dropped out of the study due to poor compliance or loss of follow-up.Of the 730 patients who fully participated in this study,371 patients did not have DVT during hospitalization.75 cases(20.2%)showed new DVT by ultrasonography within 1 month after operation.One 32-year-old man with multiple fractures developed pulmonary embolism(PE)3 weeks after surgery;A 64-year-old woman with an intertrochanteric fracture developed a fatal PE 4 weeks after surgery.Among the 75 DVT cases,3 cases had proximal thrombus,65 cases had distal thrombus,and 7 cases had mixed thrombus.The incidence of DVT was 22.4%(39/174)in patients with fractures near the knee,18.2%(16/88)in patients with fractures near the knee,and 16.9%(20/118)in patients with fractures far from the knee.There were statistically significant differences in age,anticoagulation duration,D-dimer 1 day after surgery,D-dimer at discharge,Whether coronary heart disease,whether multiple fractures,whether functional exercise between the newly diagnosed DVT group and the non-diagnosed DVT group 1 month after surgery(P < 0.05).Multivariate Logistic regression analysis showed that age > 65 years old[OR=1.094,95%CI(0.379,3.158),P=0.010],no anticoagulant therapy after discharge[OR=6.630,95%CI(1.361,32.287),P=0.019],multiple fractures[OR=5.679,95%CI(1.998,16.142),P=0.001],no functional exercise[OR=3.316,95%CI(1.146,9.589),P=0.027],high D-dimer at discharge[OR=1.064,95%CI(1.004,1.126),P=0.036]were independent risk factors for post-discharge DVT;For 359 patients with DVT during hospitalization,One month after surgery,ultrasound reexamination showed that DVT dissolved and disappeared in 161 patients,198 patients were not completely dissolved and disappeared.There were statistically significant differences in age,occurrence time of DVT,diameter of DVT,number of DVT,D-dimer 1 month after surgery,after discharge whether anticoagulation and whether multiple fractures between the vanishing DVT group and the incomplete vanishing DVT group(P <0.05).Multivariate analysis showed that DVT diameter > 7mm[OR=2.354,95%CI(1.473,9.131),P <0.001],DVT occurred before surgery[OR=3.978,95%CI(1.978,8.000),P<0.001],and D-dimer height 1 month after surgery [OR=1.792,95%CI(0.687,1.914),P=0.001]were independent risk factors for insoluble DVT in patients with lower limb fracture after discharge.Conclusion: 1.The overall incidence of DVT in patients with lower extremity fracture within 1 month after surgery was 20.2%,Although the incidence of DVT is lower than that of perioperative DVT,PE may occur even after discharge.Distal thrombus was the main type of new DVT within 1 month after operation.There was no statistical significance in the incidence of DVT among different fracture sites.2.The overall dissolution and recirculation rate of DVT within 1 month after surgery was 44.8%.The dissolution rate of DVT was the highest in patients with fractures far from the knee joint,but the dissolution of DVT was not related to the fracture site(P > 0.05).3.Most of the DVTs that were not completely dissolved and recanalized within 1 month after surgery tended to be improved under conventional anticoagulant therapy.About 17% of DVTs showed a worsening trend,And the increase of DVT is the main form of expression.4.Age > 65 years old,multiple fractures,no regular functional exercise 1 month after surgery,no anticoagulant therapy,high D-dimer at discharge were independent risk factors for DVT 1 month after surgery.5.Preoperative DVT,> 7mm diameter of DVT and high D-dimer 1 month after surgery were independent risk factors for incomplete dissolution of DVT 1 month after surgery.In clinical work,we should not only pay attention to the occurrence,prevention and treatment of DVT during hospitalization,but also pay attention to the occurrence and outcome of DVT after discharge.More attention should be paid to patients with lower limb fractures who have the risk factors mentioned above.