Compliance With Enoxaparin Dosing and Monitoring Guidelines and the Impact on Patient Length of Stay: A Pilot Study.

Background: To investigate the compliance of prescribers with the state-wide Queensland Health (QH) guidelines for dosing and monitoring of enoxaparin, and to examine the effect that compliance has on the patients' length of stay (LOS) in hospital.

Methods: A 4-week retrospective study of consecutive inpatients who were administered enoxaparin for the treatment of an embolic disease. Data collected included influential patient demographics such as weight, renal function; details of antifactor Xa (aXa) monitoring, and patient LOS. All dosing and monitoring for each patient was compared to the current QH guidelines for enoxaparin usage; a multidisciplinary consensus document. The reasons for noncompliance were quantified and explored.

Results: A total of 67 inpatients were recruited. The median (range) age, weight, and creatinine clearance of patients were 66 years (18-92), 78.5 kg (47.6-182), and 64 mL/min (16-180), respectively. Only 20 (30%) patients received enoxaparin in compliance with QH guidelines, leaving 47 (70%) noncompliant. The median (range) LOS was 7 (2-58) days for the compliant group versus 15 days (2-101) for the noncompliant (P = 0.06, Mann-Whitney U test). A total of 10 (15%) patients were monitored for aXa; none of whom were monitored correctly. Twenty-eight patients did not receive monitoring when indicated (moderate or severe renal impairment, weight >105 kg, or extended duration of therapy). In these patients, the median (range) LOS was 16.5 days (2-101).

Conclusions: Current prescribing of enoxaparin does not match state guidelines. Although not significant, there was a trend toward noncompliant patients having a greater LOS in hospital. The quality of aXa monitoring is suboptimal and barriers need to be explored. Larger studies are warranted.