RESUMO
BACKGROUND: Obese patients experience a higher risk of venous thromboembolism (VTE) than their nonobese counterparts, which may warrant a more aggressive approach to thromboprophylaxis in this population. OBJECTIVE: The purpose of this study was to compare rates of nosocomial VTE in obese patients treated with high-dose versus conventional-dose subcutaneous unfractionated heparin sodium (UFH) for thromboprophylaxis. METHODS: A retrospective, single-center, cohort study was conducted to evaluate obese, adult, hospitalized patients admitted between April 2011 and April 2014 who received heparin 5,000 or 7,500 units subcutaneously every 8 hours for thromboprophylaxis. The primary outcome assessed the rate of nosocomial VTE in obese patients treated with high-dose heparin (7,500 units subcutaneously q 8 h) versus conventional-dose heparin (5,000 units subcutaneously q 8 h). Additionally, a secondary outcome assessed safety by quantifying bleeding events. RESULTS: Nosocomial VTE occurred in 2/196 (1.02%) patients who received high-dose heparin thromboprophylaxis and in 5/2,182 (0.23%) patients who received conventional-dose heparin (p = .05). Bleeding occurred in 0/196 (0%) patients in the high-dose heparin group and in 2/2,182 (0.09%) patients in the conventional-dose heparin group (p = .67). All bleeding events were minor. CONCLUSIONS: This study failed to demonstrate a statistically significant reduction in the rate of nosocomial VTE in obese patients who received high-dose heparin thromboprophylaxis. Despite receiving a higher heparin dose, no increased risk of bleeding was observed in the high-dose group. Further investigation is needed to identify the optimal heparin dose for thromboprophylaxis in obese patients.
RESUMO
PURPOSE: Results of an investigation of the pharmacodynamic effect of rivaroxaban anticoagulation, as measured by prothrombin time (PT), on bleeding risk and other outcomes in hospitalized patients are reported. METHODS: In a single-center retrospective cohort study, adult inpatients who had a PT measured within 24 hours after rivaroxaban administration during a designated 23-month period were identified. Patients who experienced in-hospital bleeding events were compared with those who did not. A multivariable logistic regression model was used to quantify the association between PT and bleeding events while adjusting for albumin levels and use of nonsteroidal antiinflammatory drugs and/or antiplatelet agents. Thromboembolic events were assessed as a secondary outcome. RESULTS: A total of 199 patients met the criteria for inclusion in the analysis; 41 experienced a bleeding event. Among patients with a PT of ≥30 seconds versus a PT of <30 seconds, the overall rate of bleeding events was significantly higher (38.7% versus 17.3%, p = 0.0067). Results of multivariable regression modeling showed that a PT of ≥30 seconds correlated with an approximately 3-fold higher bleeding risk (odds ratio, 3.25; 95% confidence interval, 1.09-9.66). Hypoalbuminemia was also a positive predictor of bleeding risk. There was no significant between-group difference in thromboembolic events. CONCLUSION: In hospitalized patients receiving rivaroxaban who had coagulation tests performed, a PT of ≥30 seconds was associated with a higher risk of bleeding. Hypoalbuminemia was also associated with bleeding in this population.