Effect of time of admission on compliance with deep vein thrombosis prophylaxis in a tertiary medical intensive care unit

Objective: We sought to evaluate deep vein thrombosis (DVT) prophylaxis compliance according to time of admission in a medical intensive care unit (MICU). Methods: This was a retrospective cohort study at a closedtertiary MICU. We classified patients into three groups (week days, weekends, and week nights), according to time of admission. An unweighted risk factor score (RFS) was calculated from 20 known risk factors. We defined DVT prophylaxis compliance as any type of prophylaxis (mechanical or pharmacologic) for RFS≤3 or both types of prophylaxis for RFS > 3. Non-compliance was defined as no prophylaxis or single-type prophylaxis for RFS > 3. Results: We analyzed 105 admissions. Eighty (76.19%) patients received compliant DVT prophylaxis, and 25 (23.81%) patients received non-compliant regimens of whom 11 (10.48%) were not on any prophylaxis. DVT prophylaxis compliance was not different across the three admission groups. The non-compliant DVT prophylaxis group had a higher RFS (3.48 ± 2.1 vs. 2.25 ± 1.5; P = 0.011), a trend towards fewer female patients (40% vs. 60%; P = 0.079), and a higher percentage of admissions by interns at the first postgraduate year (PGY) level (28% vs. 5.4%; P = 0.01). Logistic regression revealed that only RFS and PGY level were independent predictors for compliance (P= 0.015 and 0.005 respectively). Time of admission was not a significant factor. Conclusions: Time of admission did not influence DVT prophylaxis compliance. Compliance improved with higher PGY level and lower RFS. A higher level of knowledge probably explains the association with PGY level; however, we cannot explain the inverse relationship between RFS and compliance.