Table 3.

 Predictors of two year survival for patients with acute lung injury

Predictors	Crude hazard ratio (95% CI)	P value*	Adjusted hazard ratio (95% CI)	P value*
No of ventilator settings adherent to lung protective ventilation	1.02 (1.01 to 1.04)	<0.001	0.97 (0.95 to 0.99)	0.002
Duration of mechanical ventilation	1.02 (1.01 to 1.02)	<0.001	1.01 (1.00 to 1.02)	0.182
Age	1.03 (1.02 to 1.03)	<0.001	1.03 (1.02 to 1.04)	<0.001
Male sex	1.01 (0.80 to 1.27)	0.924	0.89 (0.69 to 1.16)	0.386
Underweight (body mass index <18.5)	1.43 (0.92 to 2.23)	0.103	1.30 (0.77 to 2.18)	0.321
Overweight or obese (body mass index ≥25)	0.88 (0.70 to 1.11)	0.274	0.93 (0.71 to 1.22)	0.606
Charlson comorbidity index	1.10 (1.06 to 1.15)	<0.001	1.07 (1.02 to 1.12)	0.006
APACHE II score	1.05 (1.04 to 1.07)	<0.001	1.00 (0.98 to 1.01)	0.647
Non-pulmonary sepsis as risk factor for acute lung injury	2.04 (1.61 to 2.58)	<0.001	1.47 (1.11 to 1.95)	0.006
Admission to medical intensive care unit	1.46 (1.03 to 2.08)	0.030	1.38 (0.90 to 2.11)	0.131
Admission to intensive care unit from emergency department	0.82 (0.65 to 1.04)	0.091	0.74 (0.56 to 0.98)	0.033
Mean daily sequential organ failure assessment score	1.22 (1.18 to 1.25)	<0.001	1.20 (1.16 to 1.25)	<0.001
Days of delirium in intensive care unit	1.04 (1.03 to 1.06)	<0.001	1.02 (0.99 to 1.05)	0.160
Days of deep sedation in intensive care unit	1.04 (1.02 to 1.06)	<0.001	1.01 (0.98 to 1.04)	0.508
Days of corticosteroid use	1.04 (1.03 to 1.04)	<0.001	1.01 (0.99 to 1.03)	0.329
Cumulative dose of prednisone, per 50 mg†	1.01 (1.00 to 1.01)	0.028	1.00 (0.99 to 1.01)	0.984
Days of neuromuscular blockade	1.16 (1.07 to 1.26)	<0.001	1.16 (1.01 to 1.33)	0.036
Cumulative dose of vecuronium, per 5 mg	1.00 (1.00 to 1.01)	0.119	1.01 (0.99 to 1.02)	0.288
Cumulative fluid balance in intensive care unit, per litre	1.03 (1.02 to 1.03)	<0.001	1.02 (1.01 to 1.03)	<0.001
High frequency oscillatory ventilation, No of ventilator settings	1.04 (1.00 to 1.07)	0.022	0.93 (0.88 to 0.97)	0.002
Airway pressure release ventilation, No of ventilator settings	1.00 (0.99 to 1.02)	0.689	0.98 (0.96 to 0.99)	0.005
Mean daily positive end expiratory pressure, per 1 cm H2O	1.12 (1.07 to 1.16)	<0.001	1.10 (1.05 to 1.16)	<0.001
Mean daily PaO2:FiO2, per 10 units	1.00 (0.99 to 1.01)	0.358	1.00 (1.00 to 1.01)	0.146
No with arterial pH <7.25‡	1.12 (1.09 to 1.15)	<0.001	1.04 (0.99 to 1.10)	0.077
Mean daily static compliance of respiratory system, per 10 mL/cm H2O	0.97 (0.90 to 1.05)	0.421	0.96 (0.87 to 1.05)	0.321
Mean daily respiratory rate, per 1 breath/min	1.04 (1.03 to 1.06)	<0.001	1.02 (0.99 to 1.04)	0.162
Second year of study enrolment	1.28 (1.01 to 1.60)	0.033	1.30 (0.96 to 1.77)	0.086
Third year of study enrolment	0.88 (0.68 to 1.13)	0.305	1.17 (0.83 to 1.64)	0.357
Study site 2	1.05 (0.82 to 1.34)	0.698	1.30 (0.92 to 1.84)	0.133
Study site 3 and 4§	0.76 (0.59 to 0.98)	0.030	1.23 (0.85 to 1.77)	0.257

APACHE II=acute physiology and chronic health evaluation II; PaO₂=partial pressure of arterial oxygen; FiO₂=fraction of inspired oxygen.

*From Cox proportional hazards regression model.

†Corticosteroid dose presented as prednisone-equivalent; conversions done using standard methods.⁴³

‡From arterial blood gas measurements abstracted from medical records twice daily, when available.

§Sites were combined for analysis as site 4 had a small sample size and shared all intensive care unit physicians with site 3.