Total (N=163) | TBI (n=41) | Non-TBI (n=122) | P value | |
Time to initiate enoxaparin, median d | 2 (1–6) | 7.5 (3–10) | 1.5 (1–4) | <0.01 |
Days to first anti-Xa level drawn, median d | 4 (2–7) | 9 (5–11.5) | 3 (2–6) | <0.01 |
Within goal at first measure, n (%) | 63 (38.7) | 15 (36.6) | 48 (39.3) | 0.75 |
Days to reach goal (from admission), median d | 6 (6–13) | 11 (7–16) | 5 (2–10) | <0.01 |
Dose adjustments to reach goal, median n | 1 (0–1) | 1 (0–2) | 1 (0–1) | 0.61 |
Optimal dose based on anti-Xa levels (mg), median | 40 (30–40) | 40 (30–50) | 40 (30–40) | 0.73 |
Patients given prophylactic unfractionated heparin prior to enoxaparin, n (%) | 33 (20.2) | 19 (46.3) | 14 (11.5) | <0.01 |
Days to initiate prophylactic unfractionated heparin, median d | 3 (1–3) | 3 (2–4) | 1 (0–3) | 0.01 |
Patients who underwent IVC filter placement, n (%) | 8 (4.9) | 4 (9.8) | 4 (3.3) | 0.11 |
Duplex ultrasonography ordered based on clinical suspicion, n (%) | 50 (30.7) | 13 (31.7) | 37 (30.3) | 0.87 |
Days to first duplex ultrasonography performed, median d | 7.5 (5–12) | 10 (6.5–13) | 6 (4–11) | 0.07 |
Chest CT angiography ordered, n (%) | 22 (13.5) | 6 (14.6) | 16 (13.1) | 0.81 |
Days to first chest CT angiography based on clinical suspicion, median d | 8 (5–18) | 16.5 (8–22) | 7 (5–12) | 0.25 |
IVC, inferior vena cava; TBI, traumatic brain injury.