The Application Value of the D-Dimer Critical Value in Diagnosing Deep Vein Thrombosis in Patients with Bone Trauma.

Background: D-dimer is used as a clinical indicator to predict venous thromboembolism, and some hospitals have included it in the critical value project. We aimed to evaluate whether the setting of a D-dimer critical value is helpful in the diagnosis of deep vein thrombosis in patients with bone trauma and to explore the rationality of setting a D-dimer critical value limit.
Methods: The clinical data of 4,897 bone trauma patients, hospitalized from April 1, 2022, to March 31, 2023, were retrospectively analyzed. Our hospital set the critical value limit for when the D-dimer value was greater than 15.0 mg/L, and Bayesian model was used to evaluate the relationship between deep vein thrombosis and the D-dimer limit.
Results: During this period, 199 times the D-dimer detection value was greater than 15.0 mg/L, and the critical value was reported and accounted for 4.06%. The predicted probability of lower limb venous thrombosis in patients who triggered the critical value of D-dimer was 40.21%, and the actual incidence was 34.67%. There were 376 patients with lower limb venous thrombosis during hospitalization, and 81.38% of the D-dimer value did not reach the critical value limit.
Conclusions: The role of D-dimer as a critical value item in predicting DVT in patients with orthopedic trauma is small. Whether to list D-dimer as a critical value item can be comprehensively considered according to the own situation of medical institutions and the recommendations of clinicians. The same can be applied for the setting of critical value boundaries.