Abstract

Background: Venous thromboembolism (VTE) is the third leading cause of cardiovascular mortality in developed countries. Patients undergoing major lower extremity orthopedic surgeries, such as total hip arthroplasty, total knee arthroplasty, and femoral fracture fixation, are at high risk, with an estimated incidence of deep vein thrombosis ranging from 40% to 60% in the absence of prophylaxis. Optimal use of anticoagulant 220 TẠP CHÍ Y DƯỢC HUẾ - HUE JOURNAL OF MEDICINE AND PHARMACY ISSN 3030-4318; eISSN: 3030-4326 therapy is essential due to the risk of bleeding and the narrow therapeutic window. Objective: To evaluate the utilization, appropriateness of pharmacological prophylaxis for VTE according to the 2022 Vietnam National Heart Association (VNHA 2022) guidelines, and associated factors in patients undergoing lower extremity orthopedic surgery at Da Nang Hospital. Methods: A cross-sectional descriptive study was conducted on 150 medical records of patients aged ≥ 18 years who underwent lower extremity orthopedic surgery and received pharmacological VTE prophylaxis from May 2024 to April 2025. Results: The most commonly used agents were rivaroxaban (57.3%), enoxaparin combined with rivaroxaban (32.0%), enoxaparin alone (4.7%), and other combinations (6.0%). The mean total duration of prophylaxis was 16.3 ± 7.1 days. The appropriateness rates according to VNHA 2022 guidelines were: drug selection 46.7%, dosage 86.7%, timing of initiation 50.7%, and total duration of use 42.0%. Multivariable logistic regression analysis revealed that: (1) patients classified as having moderate (high or low) VTE risk according to VNHA 2022 had a 20.789- fold higher risk of inappropriate drug selection (p < 0.001); (2) fracture diagnosis (OR = 3.911), initiation with rivaroxaban (OR = 29.581), and high VTE risk according to VNHA 2022 (OR = 3.254) were significantly associated with inappropriate timing of initiation (p < 0.05); (3) male gender (OR = 2.722) and age ≥ 60 years (OR = 4.655) were significantly associated with inappropriate total duration of prophylaxis (p < 0.05). Conclusion: According to the VNHA 2022 recommendations, the appropriateness of pharmacological VTE prophylaxis was highest for the dosing criterion, with a rate of 86.7%. In contrast, the appropriateness rates for drug selection, timing of initiation, and duration of therapy remained limited. Therefore, strengthening the review, updating, and standardization of prescribing protocols is necessary to improve treatment effectiveness as well as ensure patient safety in VTE prophylaxis.