Table 3. Severity, clinical characteristics and hospital course of trauma patients according to the type of transport.

	Direct transportation (n = 4031)	Secondary transfer (n = 381)	p
Severity of injuries
SOFA (day 1)	1 [0–4]	0 [0–2]	0.02
SAPS II (day 1)	17 [10–31]	15 [10–25]	0.03
ISS	11 [5–22]	14 [9–22]	< 0.001
Major trauma ISS ≥ 16	1557 (39%)	147 (48%)	0.001
Head and neck AIS ≥ 3	900 (22%)	103 (27%)	0.04
Face AIS ≥ 2	468 (12%)	29 (8%)	0.02
Thorax AIS ≥ 3	1148 (29%)	120 (32%)	0.23
Abdomen AIS ≥ 3	408 (10%)	76 (20%)	< 0.001
Extremities pelvis AIS ≥ 3	1115 (29%)	58 (15%)	< 0.001
At admission
SAP (mmHg)	129 (27)	128 (24)	0.63
Hemoglobin (g/dL)	13.3 (2.1)	13.0 (2.0)	0.04
Lactate (mmol/L)	2.5 (2.2)	2.1 (1.5)	0.01
Prothrombin rate (%)	82 (18)	83 (15)	0.12
Surgery in the first 24h	1941 (48%)	152 (40%)	0.01
Specific characteristics
Hemorrhagic shock	266 (7%)	14 (4%)	0.03
Severe head trauma	405 (10%)	4 (1%)	< 0.001
Spine trauma	451 (11%)	85 (22%)	< 0.001
Medullary injury	116 (3%)	22 (6%)	1
Evolution and outcome
Infection	176 (23%)	16 (14%)	0.03
ICU LOS (days)	2 [2–5]	3 [2–7]	< 0.001
Hospital LOS (days)	7 [2–17]	9 [5–16]	< 0.001
Discharge from ICU			< 0.001
Ward	2938 (79%)	326 (88%)
Home	697 (19%)	34 (9%)
Other ICU	7 (0%)	4 (1%)
Rehabilitation	82 (2%)	7 (2%)
Day 30 mortality	269 (7%)	9 (2%)	0.001
Mortality over hospital stay	289 (7%)	9 (2%)	0.001
Predicted mortality by TRISS (%)	8.8%	4.7%	0.001

Qualitative variables expressed as n (%) and quantitative variables as mean (SD) or median [quartile1, 3] according to the distribution.

SOFA: sequential organ failure assessment, SAPS II: simplified acute physiologic score, ISS: injury severity score, AIS: abbreviated injury scale, SAP: systolic arterial blood pressure, ICU: intensive care unit, LOS: length of stay, TRISS: trauma related injury severity score.

Hemorrhagic shock: receiving ≥ 4 packed red blood cells concentrate within 6 hours.

Severe head trauma: Glasgow coma scale ≤ 8 and head AIS > 1.