Clinical risk factors for acute respiratory distress syndrome(ARDS) between cases, controls, survivors and nonsurvivors#
| Risk for ARDS | Development of ARDS | Mortality in ARDS | ||||
| Controls | Cases | p-value | Survivors | Nonsurvivors | p-value | |
| Subjects n | 441 | 212 | 114 | 98 | ||
| Sepsis syndrome | 167 (38) | 67 (32) | 0.1 | 44 (39) | 23 (23) | 0.03 |
| Pneumonia source | 87 (20) | 52 (25) | <0.001 | 33 (29) | 19 (19) | 0.6 |
| Extra-pulmonary source | 80 (18) | 15 (7) | 11 (10) | 4 (4) | ||
| Septic shock | 196 (44) | 115 (54) | 0.02 | 52 (46) | 63 (64) | 0.009 |
| Pneumonia source | 89 (20) | 79 (37) | <0.001 | 36 (32) | 43 (44) | >0.9 |
| Extra-pulmonary source | 107 (24) | 36 (17) | 16 (14) | 20 (20) | ||
| Trauma | 40 (9.0) | 9 (4) | 0.03 | 8 (7) | 1 (1) | 0.04 |
| Multiple transfusions | 51 (12) | 26 (12) | 0.8 | 13 (11) | 13 (13) | 0.7 |
| Aspiration | 34 (8) | 24 (11) | 0.1 | 13 (11) | 11 (11) | >0.9 |
| >1 Risk for ARDS | 48 (11) | 29 (14) | 0.3 | 16 (14) | 13 (13) | >0.9 |
| Direct pulmonary injury¶ | 211 (48) | 144 (68) | <0.001 | 79 (69) | 65 (66) | 0.7 |
| Indirect pulmonary injury+ | 230 (52) | 68 (32) | 35 (31) | 33 (34) | ||
Data are presented as n (%) or n, unless otherwise stated. #: the number of controls and cases with each risk adding up to >653 patients because of multiple risks in 77 patients; ¶: pneumonia, aspiration or pulmonary contusions were categorised as direct pulmonary injury; +: sepsis from an extra-pulmonary source, trauma without pulmonary contusions and multiple transfusions were categorised as indirect pulmonary injury. Patients (n = 69) with both direct and indirect pulmonary injuries were considered to have direct pulmonary injury.