Initiative to improve thromboprophylactic enoxaparin exposure in hospitalized patients with renal impairment

PURPOSE: The impact of a quality-improvement (QI) initiative to decrease the risk of bleeding in renally impaired patients receiving enoxaparin prophylaxis for venous thromboembolism (VTE) was evaluated. METHODS: A retrospective cohort with a before-and-after study design was employed. Inclusion criteria included age over 40 years, hospitalization exceeding six days, treatment with enoxaparin or unfractionated heparin (UFH), and acute or chronic renal insufficiency. Major bleeding included fatal bleeding, symptomatic bleeding requiring hemodynamic support or causing a decrease of 2 g/dL or more in hemoglobin concentration, or bleeding leading to the transfusion of at least 2 units of packed red blood cells. The QI intervention restricted enoxaparin use in patients with a creatinine clearance (CL(cr)) concentration of <30 mL/min and recommended UFH instead. RESULTS: The rate of major bleeding in the preintervention group was 13.5% with enoxaparin compared with 4.1% with UFH (p = 0.005). The relative risk (RR) of bleeding with enoxaparin compared with UFH was 3.21 (95% confidence interval [CI], 1.40-7.34). In patients with a CL(cr) concentration of <30 mL/min, the RR of bleeding with enoxaparin compared with UFH was 4.68 (95% CI, 1.06-20.59). The rate of major bleeding in the postintervention period was 9.5% with enoxaparin or 4.5% with UFH (p = 0.15). The RR of bleeding in the postintervention period was 0.64 (95% CI, 0.37-1.12). CONCLUSION: A QI initiative that eliminated the use of enoxaparin for prophylaxis of VTE in patients with renal impairment resulted in lower rates of major bleeding associated with pharmacologic prophylaxis. No differences in the rate of in hospital VTE as a result of the intervention were observed.