Analysis Of Risk Factors Of Venous Thromboembolism After Operation Of Urological Malignant Tumor

Objective: VTE(venous thromboembolism)including DVT(deep venous thrombosis)and PE(pulmonary embolism)is a common non-operative complication in urological surgery.It is also one of the most common causes of death within 30 days after operation of urinary malignant tumor.The purpose of this study is to explore the risk factors of VTE by summarizing the clinical data of postoperative patients with urological malignant tumors in our hospital,which is aimed to provide clinical evidence support for the establishment of a more accurate and suitable risk assessment method for postoperative VTE in patients with urinary malignant tumors in our country.Methods: A retrospective analysis was made on patients with malignant tumors who were hospitalized in the Second Affiliated Hospital of Dalian Medical University from September 2019 to November 2020 who underwent radical nephrectomy,partial nephrectomy,radical nephroureterectomy,radical cystectomy or radical prostatectomy.A total of 79 patients were divided into VTE group(n = 10)and non-VTE group(n = 69)according to the diagnosis of VTE after operation.Clinical data of patients was collected,including general data(age,sex,body mass index(BMI),smoking history,hypertension history,diabetes history,atrial fibrillation history,other medical disease history,VTE history,ASA classification),preoperative and postoperative coagulation function and infection indexes(platelet,plasma prothrombin time,partial activated thromboplastin time,international standardized ratio,fibrinogen,white blood cell,neutrophil count),operation-related data(operation method,operation area,operation lateral position,lymph node resection,operation time,intraoperative blood loss,perioperative blood transfusion,postoperative bed rest time),VTE-evaluation-related data(preoperative Caprini score,Khorana score,preoperative plasma D-dimer,postoperative Caprini score,plasma D-dimer on the day of operation and the first day after operation).The statistical analysis was carried out.The risk factors of VTE were analyzed by binary logistic regression,and the Receiver Operating Characteristic Curve(ROC curve)was drawn to evaluate the independent risk factors and the predictive value of the prediction model.Results: The total incidence of VTE was 13%(10/79).The incidence of VTE in laparoscopic radical nephrectomy,partial nephrectomy,radical nephroureterectomy,radical cystectomy and radical prostatectomy was 0,9%,29%,20% and 6%,respectively.Calf intermuscular venous thrombosis was found in all VTE patients,and asymptomatic VTE accounted for 90%.Age,≥75 years old,female,operation time,preoperative Caprini score≥5,postoperative Caprini score ≥7,plasma D-dimer levels on the day of operation and the first day after operation were all risk factors for postoperative VTE of urological malignant tumors.The independent risk factors of VTE after operation of urological malignant tumor were age ≥75 years old(OR=200.787,95%CI=2.713-14859.831,P=0.016),female(OR=26.952,95%CI=1.579-460.038,P=0.023),the time of operation(OR=1.021,95%CI=1.000-1.043,P=0.047),the level of plasma D-dimer on the first day after operation(OR=2.483,95%CI=1.028-5.999,P=0.043).According to the results,the risk prediction model of VTE after urological malignant tumor operation was put forward:X1=age≥75 years old;X2=female;X3=operation time(minutes);X4=the level of Ddimer on the first day after operation(μg/ml);Y=-12.174+5.302×X1+3.294×X2+0.021×X3+0.909×X4.ROC curve showed that when X3,X4 and Y were 167.5,1.795 and 0.11,the AUC of X1,X2,X3,X4 and Y were 0.757,0.757,0.820,0.880 and 0.970,respectively,the sensitivity was 0.6,0.6,1,0.9,1,and the specificity was 0.913,0.913,0.623,0.739 and 0.884,respectively.Conclusion:(1)The incidence of asymptomatic VTE and calf intermuscular vein thrombosis is high,which should be paid more attention.The necessity of routine reexamination of lower extremity vein ultrasound before discharge and outpatient clinic is worth discussing.(2)The predictive efficacy of Caprini score was stronger than that of Khorana score when predicting the risk of postoperative VTE in patients with urological malignant tumors,(3)If the patient is old,female,or the operation time is long,or the plasma D-dimer is high on the first day after operation,we should pay more attention to the occurrence of VTE.