Table 1 Comparative baseline demographics of the two cohorts
Derivation cohort (n = 448) | Validation cohort (n = 199) | p value | |
|---|---|---|---|
Male gender, n (%) | 213 (47.5) | 147 (73.9) | < 0.001 |
Age (years, mean ± SD) | 71.7 ± 16.6 | 58.4 ± 19.1 | < 0.001 |
SOFA score (mean ± SD) | 6.1 ± 4.1 | 7.8 ± 3.4 | < 0.001 |
APACHE II score (mean ± SD) | 15.1 ± 7.4 | 17.1 ± 5.7 | 0.001 |
CCI (mean ± SD) | 4.1 ± 2.5 | 2.6 ± 1.7 | < 0.001 |
PaO2/FiO2 ratio (mean ± SD) | 298.8 ± 112.6 | 218.5 ± 98.0 | < 0.001 |
Mechanical ventilation, n (%) | 90 (20.1) | 199 (100) | < 0.001 |
Characteristics of MV population | |||
Tidal volume (ml/kg, mean ± SD) | 6.6 ± 0.9 | 6.5 ± 0.9 | 0.179 |
PEEP level (mmHg, mean ± SD) | 5.7 ± 0.9 | 6 ± 0.9 | 0.011 |
PaO2/FiO2 ratio (mean ± SD) | 252.7 ± 113.7 | 218.5 ± 98.0 | 0.020 |
Duration of MV (days, mean ± SD) | 14.5 ± 13.8 | 14.7 ± 10.4 | 0.346 |
Underlying infection, n (%) | |||
Acute pyelonephritis | 207 (46.2) | 0 (0) | NA |
Acute intra-abdominal infection | 162 (36.2) | 0 (0.0) | NA |
Primary Gram-negative bacteremia | 71 (15.8) | 0 (0.0) | NA |
Secondary Gram-negative bacteremia (other than urinary or intra-abdominal) | 8 (1.8) | 0 (0.0) | 0.107 |
Ventilator-associated pneumonia | 0 (0) | 199 (100.0) | NA |
Early (< 7 days of MV) | 84 (42.2) | ||
Late (> 7 days of MV) | 115 (57.8) | ||
Septic shock, n (%) | 88 (19.6) | 85 (42.7) | < 0.001 |
ARDS, n (%) | 136 (30.4) | 150 (75.4) | < 0.001 |
ICU admission, n (%) | 90 (20.1) | 198 (99.5) | < 0.001 |
ICU LOS (days, mean ± SD) | 45.3 ± 94.3 | 36.9 ± 34.4 | 0.317 |
Hospital LOS (days, mean ± SD) | 20.0 ± 47.6 | 51.7 ± 47.5 | < 0.001 |
For ICU-admitted population | 49.6 ± 98.9 | 51.7 ± 47.5 | 0.006 |
For non-ICU-admitted population | 12.6 1 ± 0.9 | NA | |
ICU mortality, n (%) | 49 (54.4) | 89 (44.9) | 0.162 |
Hospital mortality, n (%) | 123 (27.5) | 110 (55.3) | < 0.001 |
28-day mortality, n (%) | 102 (22.8) | 59 (29.6) | 0.075 |
90-day mortality, n (%) | 118 (26.3) | 153 (76.9) | < 0.001 |