Study On The Screening Of Lower Extremity DVT By D-Dimer Combined With RAPT Score Among Orthopedic Trauma Patients

BackgroundVenous thromboembolism(VTE)is one of common complications of orthopedic trauma patients,including deep vein thrombosis(DVT)and pulmonary embolism(PE).DVT occurs especially in the lower extremity deep veins but occasionally in other locations.Unfortunately,among orthopedic trauma patients with lower extremity DVT,only a small number of them are symptomatic.However,the thrombus,once shedding off,could enter the pulmonary circulation and cause severe PE,leading to immediate death and resulting in great difficulty in the treatment of PE.Hence it is important to early identify patients with DVT in lower extremities and introduce anticoagulant therapy,so as to radically prevent the development of pulmonary embolism.In the current clinical practice,the common approaches to identifying DVT in lower extremities mainly include DVT Risk Assessment Scale and D-dimer.However the generally poor sensitivity of DVT Risk Assessment Scale and poor specificity of D-dimer have caused great inconvenience in their clinical application,prompting us to seek a more efficient approach to identifying DVT in lower extremities.Objective:To evaluate the clinical values of RAPT score、plasm D-dimer and the combination of these two ways for screening the lower extremity deep venous thrombosis(DVT).To select an effective and accurate method for clinicians.MethodsThe RAPT score,plasm D-dimer and lower extremity venous ultrasonography examination report were collected from our department from July,2016 to December,2016;And the dates were analyzed retrospectively.Regarding the lower extremity venous ultrasonography examination report as the "golden standard" to determine the existence of lower extremity DVT.According to the ultrasonography examination report,patients were divided into DVT group and non-DVT group,and the RAPT score and plasm D-dimer between these two groups were compared to see if there is significant difference.Then,the clinical values of RAPT score、plasm D-dimer and the combination of these two ways for screening the lower extremity DVT were analyzed and evaluated.ResultsAmong the 197 patients enrolled into the study,96 patients were diagnosed with DVT,and 101 patients were not.There were no insignificant differences in age and gender between the two groups.The D-dimer level for DVT group and Non-DVT group was 2.35(1.10,4.13)ug/ml and 0.98(0.50,1.12)ug/ml,respectively.There were significant differences in D-dimer levels between the two groups(P<0.01).The RAPT score for DVT group and Non-DVT group was 10(6,12)and 4(3,9)respectively.There were significant differences in RAPT score between the two groups(P<0.01).The patients were divided into low-risk group(≤5 points)and high-risk group(>5 points)according to RAPT score.The diagnosis of DVT was ruled out for those patients in the low-risk group and further examination was needed for those patients in the high-risk group.The sensitivity and specificity of this method were were 78.12%and 56.44%,respectively.The area under the ROC curve of RAPT score was 0.723,which showed that RAPT was valuable in diagnosing DVT of lower extremities in the orthopedic trauma patients.ROC curve was used to analyze the patient’s D-dimer levels and the optimal diagnostic value was decided by Youden’ s index,which was 1.125μg/ml.The sensitivity and specificity of this method were were 86.46%and 57.43%,respectively,and the area under the ROC curve of RAPT score was 0.803.With 0.5μg/ml as the threshold of D-dimer to screen for lower extremity DVT,the sensitivity and specificity were 97.71%and 25.74%,respectively.The lower extremity DVT was screened by the combination of RAPT score and a new threshold of D-dimer,which means that,the diagnosis of the lower extremity DVT was to be excluded for the patients whose RAPT score was estimated to be low-risk and D-dimer was less than 1.125μg/ml,otherwise,a color Doppler ultrasound examination of veins of lower extremities was to be carried out.The sensitivity and specificity of this method were 96.88%and 42.57%,respectively,and the area under the ROC curve of this method was 0.812.ConclusionCompared with only using RAPT score or D-dimmer to screen lower extremity DVT,the combination of these two methods,took both the sensitivity and specificity into account better,which further improved the specificity while ensuring high sensitivity.Unnecessary imaging examination of some patients were reduced,therefore,it was this kind of screening method meeting the requirements of the clinician and the benefits of the patients.