Table 1.
Characteristics of subjects transported by HEMS and GEMS in the training set (2007–2009)
| HEMS n = 121,424 | GEMS n = 760,302 | p value | |
|---|---|---|---|
| Age [years; med (IQR)] | 38 (24, 52) | 45 (27, 66) | <0.01 |
| Sex [n (%) male] | 86097 (71.1) | 477568 62.9 | <0.01 |
| Insurance Status | <0.01 | ||
| Commercial [n (%)] | 60,532 (49.9) | 308,268 (40.5) | |
| Subsidized/None [n (%)] | 60,892 (50.1) | 452,034 (59.5) | |
| Race [n (%)] | <0.01 | ||
| Caucasian | 100,496 (81.6) | 536,079 (68.3) | |
| Non-Caucasian | 20,928 (18.4) | 224223 (31.7) | |
| Prehospital time [mins; med (IQR)] | 58 (47, 73) | 40 (31, 52) | <0.01 |
| ISS [med (IQR)] | 13 (6, 22) | 9 (4, 13) | <0.01 |
| Age >55 [n (%)] | 24,879 (20.5) | 266,595 (35.1) | <0.01 |
| Prehospital SBP<90mmHg [n (%)] | 6,787 (5.6) | 35,340 (4.6) | <0.01 |
| Prehospital RR<10 or >29bpm [n (%)] | 9,759 (8.0) | 33,901 (4.5) | <0.01 |
| Prehospital GCS≤13 [n (%)] | 32,788 (27.0) | 113,974 (15.0) | <0.01 |
| Penetrating injury [n (%)] | 9,235 (7.6) | 90,486 (11.9) | <0.01 |
| Unstable chest wall fractures [n (%)] | 8,006 (6.9) | 20,171 (2.7) | <0.01 |
| Open skull fracture [n (%)] | 2,376 (2.0) | 7,578 (1.0) | <0.01 |
| ≥2 proximal long bone fractures [n (%)] | 3,297 (2.7) | 11,186 (1.5) | <0.01 |
| Pelvic fracture [n (%)] | 14,716 (12.1) | 51,408 (6.8) | <0.01 |
| Crush injury [n (%)] | 860 (0.7) | 2,932 (0.1) | <0.01 |
| Amputation [n (%)] | 815 (0.7) | 1,116 (0.1) | <0.01 |
| Paralysis [n (%)] | 1,121 (0.9) | 2,198 (0.3) | <0.01 |
| Hemothorax or Pneumothorax [n (%)] | 21,692 (17.9) | 59,605 (7.8) | <0.01 |
| Cardiac injury [n (%)] | 1,270 (1.0) | 5,484 (0.7) | <0.01 |
| Multisystem injury [n (%)] | 1,761 (1.5) | 2,915 (0.4) | <0.01 |
| PHY + ANA injury [n (%)] | 11,598 (9.6) | 40,218 (5.3) | <0.01 |
| Survival [n (%)] | 111,778 (92) | 723,734 (95) | <0.01 |
HEMS, helicopter emergency medical services; GEMS, ground emergency medical services; SBP, systolic blood pressure; RR, respiratory rate; GCS, Glasgow Coma Scale; PHY + ANA, any one physiologic criterion plus any one anatomic criterion