Table 1.
Cohorts characteristics
| Training | Validation | ||||
| Variables | MV non-COVID-19 cohort | MV non-COVID-19 (training) cohort | Non-COVID-19 (validation) cohort | COVID-19 cohort | MV COVID-19 subcohort |
| n | 3905 | 3124 | 781 | 5672 | 803 |
| Age, year, mean±SD | 65.0±14.7 | 65.0±14.8 | 65.3±14.4 | 60.80±17.2 | 62.1±13.9 |
| Gender | |||||
| Male, n (%) | 1741 (44.6) | 1437 (46) | 328 (42) | 2665 (47) | 319 (40) |
| Female, n (%) | 2164 (55.4) | 1686 (54) | 452 (58) | 3006 (53) | 484 (60) |
| Race or ethnicity | |||||
| White, n (%) | 1015 (26) | 749 (24) | 249 (32) | 623 (11) | 177 (22) |
| Black, n (%) | 1718 (44) | 1405 (45) | 320 (41) | 2495 (44) | 345 (43) |
| Other, n (%) | 1171 (30) | 968 (31) | 210 (27) | 2552 (45) | 281 (35) |
| ARDS determination | |||||
| PaO2/FiO2 ratio ≤300, n (%) | 3211 (82.2) | 2579 (82.6) | 632 (80.9) | 617 (10.9) | 617 (77) |
| CXR interpretation | |||||
| Yes (consistent with ARDS), n (%) | 1333 (34.1) | 35.4 (35.4) | 260 (33.3) | 565 (10) | 565 (82) |
| Indeterminant, n (%) | 313 (8.0) | 7.1 (7.1) | 60 (7.7) | 18 (.3) | 18 (2.2) |
| No (not consistent with ARDS), n (%) | 2259 (57.8) | 57.6 (57.6) | 461 (59) | 34 (.6) | 34 (4.2) |
| Risk factors | |||||
| Aspiration, n (%) | 407 (10.4) | 10.3 (10.3) | 86 (11) | ||
| Shock, n (%) | 1520 (38.9) | 39.2 (39.2) | 299 (38.3) | ||
| Pneumonia, n (%) | 1530 (39.2) | 39.8 (39.8) | 288 (36.9) | 5672 (100) | 803 (100) |
| Sepsis, n (%) | 1885 (48.3) | 48.8 (48.8) | 362 (46.4) | ||
| Pancreatitis, n (%) | 42 (1.1) | 1.1 (1.1) | 9 (1.2) | ||
| Burn, n (%) | 3 (0.1) | 3 (0.1) | 0 (0) | ||
| Overdose, n (%) | 98 (2.5) | 2.5 (2.5) | 21 (2.7) | ||
| Transfusion, n (%) | 1191 (30.5) | 30.7 (30.7) | 232 (29.7) | ||
| Congestive heart failure, n (%) | 914 (23.4) | 23.6 (23.6) | 178 (22.8) | ||
| Presence of at least one risk factor, n (%) | 2739 (70.1) | 70.6 (70.6) | 362 (46.4) | 5672 (100) | 803 (100) |
| Clinical outcomes | |||||
| Mechanically ventilated, n (%) | 3905 | 3124 | 781 | 803 (14.2) | 803 |
| ARDS, n (%) | 1646 (42.2) | 1326 (42.4) | 320 (41.0) | 583 (10.3) | 583 (72.6) |
| In-hospital mortality, n (%) | 1033 (26.5) | 848 (27.1) | 185 (23.7) | 907 (16.0) | 418 (52.1) |
| ARDS or in-hospital mortality, n (%) | 2044 (52.3) | 1655 (53.0) | 389 (49.8) | 1235 (21.9) | 746 (92.9) |
ARDS, acute respiratory distress syndrome; CXR, chest X-ray; FiO2, fractional inspired oxygen; MV, mechanically ventilated; PaO2, arterial oxygen tension.