Table 4.
Adjusted ORs for mortality, using EMS intervals (in minutes) among injury subgroups*
| Subgroup/Strata | n | Total EMS Interval | Activation Interval |
Response Interval |
On-Scene Interval |
Transport Interval |
|---|---|---|---|---|---|---|
| Ground | 3,498 | 1.00 (0.99-1.01) | 1.00 (0.95-1.05) | 1.00 (0.96-1.04) | 1.00 (0.98-1.01) | 1.00 (0.99-1.01) |
| Air | 158 | 0.97 (0.91-1.02) | 0.67 (0.25-1.79) | 1.00 (0.87-1.16) | 1.03 (0.97-1.09) | 0.93 (0.86-1.02) |
| Blunt | 2,716 | 1.00 (0.99-1.005) | 1.00 (0.95-1.05) | 1.01 (0.97-1.06) | 0.99 (0.98-1.01) | 0.99 (0.98-1.01) |
| Penetrating | 807 | 1.01 (0.99-1.04) | 1.01 (0.73-1.39) | 1.03 (0.94-1.13) | 1.02 (0.99-1.05) | 1.01 (0.96-1.06) |
| TBI (GCS score ≤8) | 1,145 | 0.99 (0.98-1.003) | 0.92 (0.82-1.03) | 0.98 (0.93-1.04) | 0.99 (0.98-1.01) | 0.99 (0.97-1.01) |
| Shock (SBP ≤70, or SBP 71-90 with pulse rate ≥108 beats/min) |
1,483 | 0.99 (0.98-1.01) | 0.86 (0.68-1.10) | 1.02 (0.95-1.09) | 1.00 (0.98-1.03) | 0.97 (0.94-1.001) |
| Advanced airway management | 945 | 0.99 (0.98-1.01) | 1.05 (0.95-1.16) | 0.97 (0.89-1.05) | 1.00 (0.98-1.02) | 0.98 (0.96-1.01) |
| Revised Trauma Score ≤2 | 79 | 1.01 (0.94-1.09) | 1.79 (0.49-6.50) | 1.32 (0.51-3.44) | 1.00 (0.93-1.08) | 1.09 (0.87-1.36) |
| BLS first arriving | 1,803 | 1.01 (0.99-1.02) | 1.03 (0.97-1.10) | 0.99 (0.94-1.05) | 1.01 (0.99-1.03) | 1.00 (0.997-1.003) |
| ALS first arriving | 1,853 | 0.99 (0.98-1.002) | 0.76 (0.60-0.96) | 1.01 (0.96-1.06) | 0.99 (0.97-1.01) | 0.99 (0.97-1.001) |
| Elders (≥65 y) | 472 | 1.00 (0.99-1.02) | 1.02 (0.96-1.07) | 0.98 (0.89-1.07) | 1.00 (0.97-1.03) | 1.03 (0.996-1.06) |
| United States | 2,610 | 0.99 (0.98-1.004)† | 1.04 (0.97-1.11) | 1.04 (0.98-1.09) | 0.99 (0.97-1.01) | 0.99 (0.97-1.01) |
| Canada | 1,046 | 1.00 (0.99-1.01) | 0.94 (0.85-1.04) | 0.97 (0.91-1.03) | 1.00 (0.98-1.02) | 1.00 (0.98-1.02) |
| Overall | 3,656 | 1.00 (0.99-1.01) | 1.00 (0.95-1.05) | 1.00 (0.97-1.04) | 1.00 (0.99-1.01) | 1.00 (0.98-1.01) |
TBI, Traumatic brain injury; BLS, basic life support; ALS, advanced life support.
*
In addition to interval, multivariable logistic regression models included the following covariates: age, sex, mode of transport, site, GCS score, SBP, respiratory rate, shock index, mechanism of injury, field intravenous or intraosseous fluid administration, tracheal intubation attempt, use of a rescue airway, field hemorrhage control, and hospital level. For each time interval point estimate, 95% confidence intervals are listed in parentheses.
†
Results for 2-step instrumental variable analyses for US trauma patients: OR 1.00 (95% CI 0.997 to 1.001).