Evaluation of Venous Thromboembolic Event Prophylaxis in Hospitalized Cancer Patients: A Single-Centered Retrospective Study

Objective: Venous thromboembolic events (VTEs) are one of the main causes of death in cancer patients. About one-third of newly diagnosed VTEs are later proved to be associated with cancers. Attempts have been made to prevent these events and reduce substantial burden on patient health. Previous studies have revealed underutilization of thromboprophylaxis in cancer patients. With respect to the high rate of enoxaparin prescription in our institute, irrational utilization of prophylactic measures was anticipated. This study aimed to evaluate the appropriateness of thromboprophylaxis in hospitalized cancer patients. Methods: Medical records of 199 cancer patients hospitalized in two oncology wards of a tertiary care teaching hospital were investigated retrospectively. Data extraction was performed by two clinical pharmacists. Appropriateness of thromboprophylaxis was determined using a local protocol prepared based on international guidelines. Findings: Forty-seven out of 199 prescriptions (23.5%) were appropriate according to the local protocol. About 76% (149/199) of patients did not have any acute medical illness or risk factors for thromboembolism and were admitted only to receive short-course chemotherapy. Enoxaparin was the drug used for 197 patients and unfractionated heparin was used for only 2 patients. Dose adjustment was not performed in three patients who needed dose modification with respect to renal impairment or obesity. Conclusion: This study has found that the frequency of thromboprophylaxis was considerably high in the study population. In the absence of an acute medical illness or other risk factors, hospitalization per se does not justify the administration of pharmacologic agents for thromboembolism prophylaxis. Implementation of local protocols prepared based on international guidelines seems necessary to rationalize thromboprophylaxis.