Pharmacist recommendations for prophylactic enoxaparin monitoring and dose adjustment in trauma patients admitted to a surgical intensive care unit

BACKGROUND: There is limited information describing pharmacist participation in prophylactic enoxaparin monitoring in the surgical intensive care unit (SICU). OBJECTIVE: Our study sought to: 1) characterize pharmacist recommendations for enoxaparin monitoring in trauma patients admitted to the SICU, 2) describe the frequency that medical providers accept pharmacist recommendations for enoxaparin monitoring in trauma patients admitted to the SICU, and 3) illustrate the frequency that trauma patients admitted to our SICU service achieve anti-factor Xa trough concentrations (AFXa-TRs) of 0.11 - 0.20 IU/mL following pharmacist recommendation to adjust prophylactic enoxaparin dosing. METHODS: Adult patients who had an AFXa-TR drawn after at least three consecutive prophylactic enoxaparin doses between June 1, 2017 and March 1, 2018 were identified through chart review and included in this study. Patients were excluded based on the following criteria: 1) age less than 18 years, 2) anti-factor Xa (AFXa) level not representative of a trough concentration, 3) AFXa-TR not representative of steady state concentration, and 4) non-trauma based prophylactic enoxaparin dosing. This study was exempt from IRB review. RESULTS: The final analysis consisted of 42 patients. A pharmacist provided at least one recommendation in 97.6% (41/42) of trauma patients with enoxaparin monitoring during their SICU stay. In total, a pharmacist made 170 recommendations, mean of 4.2 (SD 1.8) recommendations per patient. Recommendations were: 1) obtain an AFXa-TR, n=90; 2) adjust enoxaparin dose based on AFXa-TR, n=58; and 3) maintain enoxaparin dose based on AFXa-TR, n=22. Medical providers accepted 89.4% (152/170) of pharmacist recommendations for enoxaparin monitoring. Dose adjustments were made in 33 patients following pharmacist recommendation; of these, 27 had a repeat AFXa-TR following at least one dose adjustment. Target AFXa-TRs were achieved in 19/27 patients, indicating 70.4% had recommended AFXa concentrations. CONCLUSIONS: Pharmacists provided recommendations for prophylactic enoxaparin monitoring and dose adjustment in trauma patients admitted to the SICU. Medical providers regularly accepted pharmacist recommendations and trauma patients commonly achieved target AFXa-TR following pharmacist recommendation for dose adjustment. Further research is required to identify the optimal enoxaparin dose for VTE prophylaxis in trauma patients.