Demographic, injury, and VTE risk factors by chemoprophylaxis regimen
| sCP | sCP+A | Total | P value | |
| (n=8646) | (n=1886) | (n=10,532) | (sCP vs sCP+A) | |
| Age (years)* | 42 (27, 59) | 56 (35, 72) | 44 (28, 62) | <0.001 |
| Sex (% male) | 5879 (68) | 1264 (67) | 7143 (68) | 0.21 |
| Mechanism (% blunt) | 7695 (89) | 1697 (90) | 9392 (89) | 0.17 |
| Admission GCS score | 15 (14, 15) | 15 (14, 15) | 15 (14, 15) | 0.18 |
| Morbid obesity (%)* | 2009 (23) | 491 (26) | 2500 (24) | 0.03 |
| ISS* | 11 (9, 18) | 13 (9, 21) | 12 (9, 19) | <0.001 |
| Lower extremity fracture (%)* | 2013 (23) | 472 (25) | 2485 (24) | 0.10 |
| Length of stay (days) | 5 (3, 10) | 10 (5, 18) | 6 (3, 11) | <0.001 |
| Ventilator (days) | 0 (0, 0) | 0 (0, 1) | 0 (0, 0) | <0.001 |
| Prolonged ventilation (%)* | 865 (10) | 296 (16) | 1161 (11) | <0.001 |
| TESS | 4 (2, 5) | 4 (2, 6) | 4 (2, 5) | <0.001 |
| Admission TEG maximum amplitude | 64 (59, 68) | 64 (59, 68) | 64 (59, 68) | 0.81 |
| Admission TEG maximum amplitude >65 (%) | 3692 (43) | 868 (46) | 4560 (43) | 0.11 |
| Admission TEG maximum amplitude >72 (%) | 830 (10) | 202 (11) | 1010 (10) | 0.42 |
| Preadmission anticoagulant or antiplatelet therapy (%) | 338 (4) | 217 (12) | 555 (5) | < 0.001 |
| Heparinoid (any dose) (%) | 0.1 | 0.3 | 0.1 | 0.09 |
| Antiplatelet (%) | 2 | 7.2 | 2.9 | < 0.001 |
| Vitamin K antagonist (%) | 1.4 | 3.2 | 1.7 | < 0.001 |
| Direct Xa inhibitor (%) | 0.2 | 0.3 | 0.2 | 0.25 |
| Direct thrombin inhibitor (%) | 0.2 | 0.2 | 0.2 | 0.89 |
| Other risk factors (%) | ||||
| Operation >2 hours | 3248 (38) | 971 (52) | 4219 (40) | < 0.001 |
| Central venous line | 799 (9) | 744 (22) | 1210 (12) | <0.001 |
| Major venous injury/repair | 222 (3) | 123 (7) | 345 (3) | <0.001 |
| Blood products, >4 units | 614 (7) | 212 (11) | 826 (8) | < 0.001 |
| IVC filter placement | 222 (3) | 123 (7) | 345 (3) | < 0.001 |
| Spine fracture | 2326 (27) | 597 (32) | 2923 (28) | < 0.001 |
| Spinal cord injury | 136 (2) | 43 (2) | 179 (2) | 0.03 |
| Pelvis fracture | 1150 (13) | 250 (13) | 1400 (13) | 0.88 |
| Cardiovascular disease | 2561 (30) | 935 (50) | 3496 (33) | < 0.001 |
| COPD | 193 (2) | 87 (5) | 280 (3) | < 0.001 |
| Smoker | 1989 (23) | 343 (18) | 2332 (22) | < 0.001 |
| Malignancy (active or history of) | 53 (0.6) | 14 (0.7) | 67 (0.6) | 0.52 |
Risk factors for VTE in patients with standard chemoprophylaxis compared with patients with adjunctive aspirin. All values are reported as raw numbers with percentages as indicated or median values with associated interquartile ranges.
Morbid obesity defined as body mass index of greater than 35 kg/m2.
Heparinoid includes unfractionated heparin or low molecular weight heparin.
*Included in TESS.
COPD, Chronic Obstructive Pulmonary Disease; GCS, Glasgow Coma Scale; ISS, Injury Severity Score; IVC, Inferior Vena Cava; sCP, standard chemoprophylaxis; TEG, thromboelastography; TESS, Trauma Embolic Scoring System. A TESS of 6 or higher is predictive of a higher risk of VTE; VTE, venous thromboembolism.