Analyzing The Risk Factors Of Deep Venous Thrombosis In The Lower Extremities Of Elderly Patients Undergoing Total Hip Replacement Under General Anesthesia

Objective:By investigating and analyzing the risk factors of deep venous thrombosis in the lower extremities of elderly patients undergoing total hip replacement under general anesthesia,the occurrence and risk factors of deep venous thrombosis in the lower extremities of elderly patients undergoing total hip replacement under general anesthesia were discussed.The ultimate aim is to provide evidence for reducing the incidence of deep venous thrombosis in lower extremities of elderly patients undergoing total hip replacement under general anesthesia.Methods:398 elderly patients undergoing total hip replacement under general anesthesia were randomly selected as the study subjects in Nanjing drum tower medical college and Nanjing Pukou hospital from January 2015 to June 2018.All patients met the inclusion and exclusion criteria.The inclusion criteria:(1)patients are over 60 years old;(2)patients undergoing total hip replacement under general anesthesia;(3)patients with complete medical records.The exclusion criteria:(1)patients had active bleeding,patients with a recent history of spontaneous intracranial hemorrhage;(2)patients with lower extremity deep venous thrombosis before surgery;(3)patients with combined malignant tumors;(4)patients treated with anticoagulant drugs;(5)patients with severe organic diseases of heart,brain,lung,liver and kinney;(6)other patients who may have influenced the result of the study.The incidence of deep venous thrombosis was observed,and color doppler ultrasound was performed on 5～10 days after operation.A retrospective analysis was made on the clinical medical records of the same group of qualified medical and nursing staff after unified training,including age,sex,height,weight,smoking history,history of hypertension,history of myocardial infarction,varicose veins of lower extremities,blood sugar,lipid status,D-dimer status,operation time,hip replacement status,and so on.Use of bone cement and multimode postoperative analgesia enhanced recovery post-operative ambulation.Statistical analysis of risk factors that may affect deep venous thrombosis in patients of hip arthroplasty were performed.Results:In 398 elderly patients with hip replacement,136 patients with deep venous thrombosis of the lower extremities were found,and the incidence was34.17%.Among 328 cases of unilateral total hip replacement,103 cases had lower extremity deep venous thrombosis;among 158 cases of left total hip replacement,50cases had left lower extremity deep venous thrombosis(28 cases had simple left lower extremity deep venous thrombosis,17 cases had simple right lower extremity deep venous thrombosis,5 cases had double lower extremity deep venous thrombosis);170cases had right total hip replacement.Among them,there were 53 cases of deep venous thrombosis of lower extremity(18 cases of simple deep venous thrombosis of left lower extremity,29 cases of simple deep venous thrombosis of right lower extremity and 6cases of deep venous thrombosis of both lower extremities).Among 70 patients undergoing bilateral simultaneous total hip replacement,33 had deep venous thrombosis(16 had simple left lower extremity deep venous thrombosis,14 had simple right lower extremity deep venous thrombosis and 3 had bilateral lower extremity deep venous thrombosis).In these elderly patients,age over 70,body mass index greater than25 kg/m~2,diabetes mellitus,myocardial infarction,varicose veins of lower extremities,triglyceride greater than or equal to 1.7 mmol/L,D-dimer greater than or equal to 500μg/L,operation time longer than 2 hours,bilateral simultaneous replacement,use of bone cement and 3 days after operation,still not getting out of bed,the incidence of deep venous thrombosis after hip replacement was higher than that of other patients(P<0.05).There was no significant correlation between gender,smoking or hypertension and the occurrence of deep venous thrombosis after operation(P>0.05).The results of logistic regression analysis showed:>70 years,body mass index>25kg/m~2,suffering from diabetes,triglyceride≥1.7mmol/L,the numerical value of D-Dimer≥500μg/L and the operation time>2h were the risk factors of deep venous thrombosis for the elderly patients of hip arthroplasty(OR>1,P<0.05).While without the use of bone cement,only unilateral replacement and out of bed activity within 3 days after operation were the protective factors of deep venous thrombosis for the elderly patients of hip arthroplasty(OR<1,P<0.05).Conclusion:The incidence of deep venous thrombosis of lower limbs in elderly patients undergoing total hip replacement under general anesthesia is higher.Older age,obesity,diabetes mellitus,triglyceride(>1.7mmol/L),D-dimer(>500μg/L)and longer operation time are closely related to the occurrence of deep venous thrombosis after total hip arthroplasty under general anesthesia.we can take intervention measures against the related risk factors.We should try to avoid bilateral simultaneous replacement and multimode postoperative analgesia,encourage patients to get out of bed early after surgery,and ultimaltely reduce the incidence of deep vein thrombosis in elderly patients undergoing total hip replacement under general anesthesia.