2025 Southeastern Residency Conference

Title: Evaluation of Pharmacist-Initiated Dose Adjustment of Prophylactic Enoxaparin in Low Body Weight Patients 
 
Authors: 

• Cody Seward
• Breanne Wofford
• Kimberly Keller
• Brooke Brown
• Kaylee Behal
• Shaun Rowe
• Sarah Crowell
• Miller Hadley
• Ava Mosadegh

 
Objective: Compare the impact of a Pharmacy & Therapeutics (P&T) committee-approved protocol for pharmacist-driven adjustment of prophylactic enoxaparin dosing among low body weight patients pre- and post-protocol.  
 


Background:

• Enoxaparin is commonly used for venous thromboembolism (VTE) prevention in acutely ill patients; however, low body weight may increase the risk of bleeding with standard dosing (40 mg daily). Low-dose enoxaparin (30 mg daily) has shown similar VTE prevention with lower bleeding rates. This study evaluates the impact of a pharmacist-initiated Pharmacy & Therapeutics (P&T) protocol on enoxaparin dosing adjustments in low body weight patients. 

Methods:

• This quasi-experimental study, approved by the institutional review board, included 205 patients from September 1, 2022, to September 1, 2024. The P&Tprotocol allowing pharmacists to reduce enoxaparin doses for low body weight patients was implemented on October 31, 2023. Inclusion criteria were patients aged ≥ 18 years, receiving either enoxaparin 30 mg twice daily or 40 mg daily, with a BMI ≤18 or body weight ≤45 kg. Exclusion criteria included Creatinine Clearance <30 mL/minute at the time of enoxaparin initiation (Cockroft-Gault using adjusted body weight), therapeutic anticoagulation indication, acute thrombus on admission, active bleeding on admission, pregnant or peripartum, admitted or transferred to any ICU service, platelets < 50,000 cells/microliter, and patients with neuraxial catheters.Patients were required to receive at least two doses of enoxaparin to be included. Pre- and post-protocol groups were compared in accordance with when the P&T protocol was implemented. The primary outcome was whether or not the enoxaparin dose was appropriately adjusted to the reduced dose. Secondary outcomes included the title of the person initiating dose changes, time until adjustment, and bleeding incidence (defined by ISTH criteria). 

Results:

• The analysis included 115 pre-protocol and 90 post-protocol encounters. The post-protocol group had significantly more appropriate enoxaparin dose adjustments to 30 mg daily (40 [33.0%] vs 75 [77.9%], p < 0.0001). Of those that received dose adjustments, pharmacists were the providers more commonly making dose adjustments (70 [77.9%] vs 4 [4.4%], p < 0.0001). The length of hospital stay was similar in both groups (4.9 days vs 5.2 days, p = 0.2582). There were no significant differences in the time to appropriate dosing (0 [0,0] days vs 0 [0,1] days, p = 0.0676). Additionally, there were no major differences ineither major (0% in pre-protocol vs 0% in post-protocol) or minor bleeding incidence (0% in pre-protocol vs 1.1% in post-protocol, p = 0.439) between the groups. 

Conclusions:

• A pharmacist-initiated P&T-approved dose-adjustment protocol resulted insignificantly more appropriate dose adjustments of enoxaparin by pharmacists, with no difference in bleeding events. The lack of bleeding events in either group may be a result of the low number of patients included in this study compared to other similar studies. The relatively short length of stay may also have contributed to the lack of bleeding events, as the follow-up period lasted only until hospital discharge; patients who experienced bleeding events after hospital discharge would not have had the event recorded in this study. Further study is needed with a larger sample size to fully understand the safety benefits of a pharmacist-initiated dose adjustment protocol of enoxaparin and whether such a protocol should be considered for broader implementation to enhance clinical outcomes in low body weight hospitalized patients at risk for VTE.