Table 2. Risk factors for 60-day mortality.
| ARDS | Non-ARDS | All | ||||||||
| Total | Death | 75% survival | p | Total | Death | 75% survival | p | p | ||
| n | n (%) | Day | n | n (%) | Day | |||||
| Gender | 0.362 | 0.945 | 0.461 | |||||||
| Male | 56 | 25 (45) | 29 | 69 | 25 (36) | 38 | ||||
| Female | 19 | 6 (32) | 17 | 34 | 13 (38) | 14 | ||||
| Age | 0.053 | 0.023 | 0.004 | |||||||
| Smoking status | 0.745 | 0.24 | 0.321 | |||||||
| Non-smoker | 55 | 23 (42) | 27 | 81 | 32 (40) | 25 | ||||
| Smoker | 20 | 8 (40) | 17 | 21 | 5 (24) | - | ||||
| Diabetes | 0.707 | 0.988 | 0.717 | |||||||
| Non-diabetic | 59 | 22 (37) | 20 | 80 | 29 (36) | 17 | ||||
| Diabetic | 16 | 9 (56) | 39 | 23 | 9 (39) | 28 | ||||
| Baseline severity of illness (1st 24 hours of ICU admission) | ||||||||||
| APACHE II* | 0.048 | 0.0002 | <0.0001 | |||||||
| Systolic blood pressure | 0.364 | 0.527 | 0.951 | |||||||
| ≥90 mmHg | 52 | 20 (38) | 29 | 70 | 27 (39) | 25 | ||||
| <90 mmHg | 21 | 10 (48) | 11 | 33 | 11 (33) | 19 | ||||
| Heart rate | 0.278 | 0.093 | 0.55 | |||||||
| ≤100 beats/min | 15 | 8 (53) | 31 | 20 | 4 (20) | 57 | ||||
| >100 beats/min | 57 | 22 (39) | 17 | 82 | 34 (41) | 17 | ||||
| Respiratory rate | 0.403 | 0.019 | 0.23 | |||||||
| ≤30 breaths/min | 41 | 18 (44) | 20 | 74 | 23 (31) | 45 | ||||
| >30 breaths/min | 31 | 12 (39) | 29 | 27 | 15 (56) | 11 | ||||
| Creatinine | 0.997 | 0.004 | 0.028 | |||||||
| ≤2.0 mg/L | 53 | 22 (42) | 20 | 66 | 18 (27) | 60 | ||||
| >2.0 mg/L | 22 | 9 (41) | 27 | 37 | 20 (54) | 12 | ||||
| Bilirubin | 0.895 | 0.296 | 0.45 | |||||||
| ≤2.0 mg/dL | 53 | 23 (43) | 24 | 59 | 20 (34) | 42 | ||||
| >2.0 mg/dL | 21 | 8 (38) | 11 | 35 | 14 (10) | 11 | ||||
| Thrombocytopenia | 0.022 | 0.436 | 0.024 | |||||||
| Platelet >80×109/L | 46 | 15 (33) | 34 | 77 | 27 (35) | 19 | ||||
| Platelet ≤80×109/L | 28 | 16 (57) | 9 | 26 | 11 (42) | 21 | ||||
| Albumin | 0.59 | 0.071 | 0.297 | |||||||
| ≥25 g/dL | 59 | 22 (37) | 20 | 75 | 31 (41) | 18 | ||||
| <25 g/dL | 16 | 9 (56) | 25 | 25 | 6 (24) | - | ||||
| Arterial pH | 0.208 | 0.149 | 0.051 | |||||||
| ≥7.33 | 47 | 16 (34) | 31 | 67 | 21 (31) | 42 | ||||
| <7.33 | 28 | 15 (54) | 13 | 36 | 17 (47) | 12 | ||||
| Predisposing conditions for ARDS | ||||||||||
| Sepsis | 0.959 | 0.831 | 0.959 | |||||||
| No sepsis | 6 | 2 (33) | 19 | 23 | 7 (30) | 17 | ||||
| Sepsis | 69 | 29 (42) | 24 | 80 | 31 (39) | 22 | ||||
| Septic shock | 0.014 | 0.273 | 0.486 | |||||||
| No septic shock | 44 | 13 (29) | 34 | 56 | 22 (39) | 17 | ||||
| Septic shock | 31 | 18 (58) | 10 | 47 | 16 (34) | 28 | ||||
| Pneumonia | 0.382 | 0.001 | 0.002 | |||||||
| No pneumonia | 46 | 17 (37) | 19 | 68 | 19 (28) | 42 | ||||
| Pneumonia | 29 | 14 (48) | 24 | 35 | 19 (54) | 12 | ||||
| Pancreatitis | 0.01 | 0.967 | 0.061 | |||||||
| No pancreatitis | 63 | 30 (48) | 17 | 92 | 34 (37) | 25 | ||||
| Pancreatitis | 12 | 1 (8) | - | 11 | 4 (36) | 8 | ||||
| Trauma | 0.163 | 0.241 | 0.071 | |||||||
| No trauma | 72 | 31 (43) | 20 | 100 | 38 (38) | 19 | ||||
| Trauma | 3 | 0 (0) | - | 3 | 0 (0) | - | ||||
| Multiple transfusions | 0.629 | 0.365 | 0.311 | |||||||
| No multiple transfusions | 70 | 29 (41) | 24 | 93 | 36 (39) | 19 | ||||
| Multiple transfusions | 5 | 2 (40) | 46 | 10 | 2 (20) | - | ||||
| Aspiration | 0.92 | 0.434 | 0.856 | |||||||
| No aspiration | 65 | 27 (42) | 24 | 101 | 38 (38) | 19 | ||||
| Aspiration | 10 | 4 (40) | 7 | 2 | 0 (0) | - | ||||
| Pulmonary injury† | 0.812 | 0.003 | 0.013 | |||||||
| Direct pulmonary injury | 36 | 14 (39) | 17 | 67 | 19 (28) | 42 | ||||
| External pulmonary injury | 39 | 17 (44) | 29 | 36 | 19 (53) | 12 | ||||
ARDS = acute respiratory distress syndrome; APACHE = Acute Physiology and Chronic Health Evaluation; ICU = intensive care unit.
*APACHE II score was calculated with all components within 24 hours of ICU admission;
†
Pneumonia, aspiration, pulmonary contusions, or sepsis from lower pulmonary source were categorized as direct pulmonary injury; sepsis from an extrapulmonary source, trauma without pulmonary contusions, and multiple transfusions were categorized as external pulmonary lung injury. Patients with both direct and external pulmonary injuries were considered to have direct lung injury.