Table 1.
Baseline characteristics
| Variables | Overall (N = 202) |
Non-Survivors (N = 63; 31%) |
Survivors (N = 139; 69%) |
p-value |
|---|---|---|---|---|
| Age (years) | 59.0 [43.0, 71.0] | 69.00 [52.0, 76.5] | 56.0 [39.0, 67.0] | < 0.001 |
| Male—N (%) | 127 (62.9) | 38 (60) | 89 (64) | 0.73 |
| APACHE IIa | 19.0 [15.0, 23.0] | 21.0 [17.0, 24.0] | 18.0 [15.0, 23.0] | 0.15 |
| Non-respiratory SOFA score | 8.00 [5.00, 10.0] | 8.00 [7.0, 11.0] | 7.0 [4.0, 9.5] | 0.03 |
| Admission source–N (%) | ||||
| Emergency | 145 (71.8) | 46 (73) | 99 (71) | 0.92 |
| Elective | 11 (5.4) | 3 (4.8) | 8 (6) | 1.00 |
| Medical | 89 (44.1) | 27 (43) | 62 (45) | 0.94 |
| Surgical | 71 (35.1) | 26 (41) | 45 (32) | 0.29 |
| ARDS severity—N (%) | ||||
| Mild | 78 (38.6) | 25 (39.7) | 53 (38.1) | 0.809 |
| Moderate | 90 (44.6) | 29 (46.0) | 61 (43.9) | |
| Severe | 34 (16.8) | 9 (14.3) | 25 (18.0) | |
| ARDS risk factor—N (%) | ||||
| Trauma | 36 (17.8) | 8 (13) | 28 (20) | 0.28 |
| Pneumonia | 140 (69.3) | 44 (70) | 96 (69) | 1.00 |
| Non-pulmonary sepsis | 36 (17.8) | 14 (22) | 22 (16) | 0.37 |
| Oxygenation parameters | ||||
| PaO2 (kPa) {mmHg} | 11.1 [9.7, 13.5] | 11.6 [10.0, 14.1] | 11.0 [9.5, 12.8] | 0.09 |
| {83.3 [72.8, 101.3]} | {87 [75, 105.8]} | {82.5 [71.3, 96.0]} | ||
| FiO2 | 0.5 [0.4, 0.8] | 0.5 [0.4, 0.7] | 0.5 [0.4, 0.8] | 0.61 |
| P/F ratio (kPa) {mmHg} | 23.9 [16.2, 31.0] | 24.7 [18.2, 34.2] | 23.5 [15.4, 30.0] | 0.11 |
| {179.3,[121.5, 232.5]} | {185.3 [136.5, 256.5]} | {176.3 [115.5, 225.0]} | ||
| SaO2 (%)b | 97.4 [95.5, 98.5] | 97.7 [96.0, 98.8] | 97.3 [95.3, 98.2] | 0.27 |
| Ventilation parameters | ||||
| Tidal volume (ml/kg PBW) | 7.1 [6.3, 8.4] | 7.3 [6.4, 8.6] | 7.1 [6.3, 8.3] | 0.32 |
| PEEP (cmH2O) | 8.0 [5.0, 10.0] | 7.0 [5.0, 8.0] | 8.0 [5.0, 10.0] | 0.05 |
| Mean airway pressure (cmH2O)d | 13.0 [9.0, 16.0] | 13.0 [9.0, 15.0] | 12.0 [10.0, 16.0] | 0.57 |
| Lactate (mmol/L) | 1.2 [0.8, 1.8] | 1.4 [1.0, 2.0] | 1.1 [0.8, 1.6] | 0.02 |
| Vasopressor use—N (%)* | 114 (56.4) | 41 (65) | 73 (52) | 0.13 |
| Adjunctive therapies# | ||||
| Neuromuscular blockade—N (%) | 62 (30.7) | 14 (22) | 48 (35) | 0.11 |
| Nitric oxide—N (%) | 25 (12.4) | 9 (14) | 16 (11) | 0.75 |
| Prone positioning—N (%) | 14 (6.9) | 5 (8) | 9 (6) | 0.94 |
Data are presented as median [IQR] unless otherwise stated
Values of oxygenation are presented in kPa, and the corresponding values in mmHg is presented in italics
APACHE II, Acute physiology and chronic health evaluation II; SOFA, Sequential organ failure assessment score; PaO2, partial pressure of arterial oxygen; FiO2,Fraction of inspired oxygen; P/F ratio, partial pressure of arterial oxygen to fraction of inspired oxygen ratio; SaO2, Saturation of arterial oxygen; PBW, predicted body weight; PEEP, Positive end-expiratory pressure
*At time of ARDS diagnosis
#Use within first 7 days of ARDS diagnosis
a12.9% of patients with missing data (17 survivors, 9 non-survivors)
b4.0% of patients with missing data (4 survivors, 4 non-survivors)
c7.4% of patients with missing data (9 survivors. 6 non-survivors)