PSHP 2026 Residency Conference

The purpose of this research project is to evaluate current dosing practices and identify opportunities to improve safety in underweight and overweight patients through development and implementation of a dosing guideline.


A retrospective chart review was conducted to evaluate adult patients from January to June 2025 who received venous thromboembolism (VTE) prophylaxis with enoxaparin and unfractionated heparin (UFH) and qualified for dosing adjustments instead of standard prophylaxis dosing. Inclusion criteria were adult patients weighing ≤ 45 kg (or with a body mass index (BMI) ≤ 18.5 kg/m2) or weighing ≥100 kg (or with a BMI ≥30 kg/m2) who received VTE prophylaxis for at least 48 hours. The primary outcome was incidence of VTE. Secondary outcomes include major bleeding events, duration of therapy, change in VTE prophylaxis regimen during the same admission period, and length of stay. A dosing guideline was developed and approved by the appropriate committees followed by staff education.  Post guideline implementation data was collected from January to March 2026 to assess guideline compliance. This quality improvement project received IRB exemption.


Pre-guideline data (n=299 total) resulted in underweight patients with standard dose UFH having a 9.1% post-discharge bleeding rate and 4.5% VTE rate, while reduced-dose recipients had none for both. Standard-dose enoxaparin had an 11.8% VTE rate versus none with reduced dosing. Among overweight patients, standard-dose UFH had a 2% inpatient bleeding rate and 2% VTE rate. Post-guideline data (n=123 total) showed 88% and 86% guideline compliance in underweight and overweight patients, respectively. Underweight patients with reduced-dose UFH had one VTE event and reduced-dose enoxaparin had one inpatient bleeding event. Overweight patients receiving dose-adjustments had 9.1% and 7.9% bleeding rates with UFH and enoxaparin, respectively.


Preliminary data suggests greater awareness of dose adjusting enoxaparin compared to heparin. In overweight patients, dosing remained more conservative than dosing in underweight patients. After the implementation of a weight-based VTE prophylaxis guideline, VTE events were reduced. Bleeding events persisted in some dose-adjusted groups, which highlights the importance of continued monitoring and further study with a larger sample size.