Table 2.

Multivariable logistic regression model evaluating the association between total out-of-hospital time and 28-day mortality among the shock cohort (n = 778).^*

	Unadjusted		Adjusted
Modeled variables†	Odds Ratio	95% CI	Odds Ratio	95% CI
Total EMS time (minutes)
≤ 30 (n=172)	1.00	reference	1.00	reference
30-45 (n=271)	0.94	(0.61, 1.45)	0.97	(0.52, 1.82)
45-60 (n=161)	0.85	(0.52, 1.39)	0.69	(0.33, 1.46)
> 60 (n=174)	0.96	(0.59, 1.54)	1.16	(0.51, 2.65)
Age
per 5-year increment for age < 45	0.96	(0.88, 1.06)	1.02	(0.89, 1.16)
per 5-year increment for age ≥ 45	1.17	(1.06, 1.29)	1.45	(1.25, 1.68)
Male	0.86	(0.59, 1.26)	0.84	(0.49, 1.46)
Penetrating injury	0.60	(0.42, 0.84)	3.31	(1.79, 6.12)
Injury severity score (ISS)	1.06	(1.04, 1.07)	1.06	(1.04, 1.07)
Qualifying SBP range (mmHg)
≤ 50	4.57	(2.74, 7.61)	6.58	(3.06, 14.16)
51-60	2.26	(1.21, 4.24)	4.55	(1.89, 10.94)
61-70	1.45	(0.82, 2.55)	3.32	(1.48, 7.45)
71-80	1.30	(0.70, 2.44)	2.61	(1.13, 6.01)
81-90	1.00	reference	1.00	reference
Highest heart rate (beats/m)
< 50	24.88	(5.50, 112.45)	6.90	(1.16, 40.94)
50-110	1.00	reference	1.00	reference
> 110	1.15	(0.81, 1.65)	1.61	(0.95, 2.72)
Initial GCS (per increment of 1)	0.76	(0.73, 0.80)	0.83	(0.78, 0.88)
Advanced airway attempted	7.67	(5.31, 11.07)	5.02	(2.58, 9.77)
Air transport	1.14	(0.80, 1.63)	0.49	(0.24, 0.99)

Abbreviations: CI, confidence interval; EMS, emergency medical services; GCS, Glasgow Coma Scale; SBP, systolic blood pressure.

^*Site was included in the model as a fixed effects term to account for clustering.

^†The polytomous time variable is presented for clarity and detail across segments of time. We used multiple imputation for the following variables (counts): age (1), ISS (31), heart rate (4), and GCS (1). Partial Abbreviated Injury Scale (AIS) data were available for all patients missing ISS score. Age modeled as spline with one knot specified at 45 years.