Baseline characteristics of patients in group P and group S
| Group P (n=21) | Group S (n=19) | p-value | |
| Male [n (%)] | 13 (62%) | 0 (0%) | <0.001 |
| Age (y) | 63 [55; 75] | 49 [42; 55] | <0.001 |
| Suspected infection [n (%)] | 15 (71%) | 0 (0%) | <0.001 |
| Pulmonary infection | 12 (57%) | 0 (0%) | <0.001 |
| Abdominal infection | 1 (5%) | 0 (0%) | 0.347 |
| Urinary infection | 4 (19%) | 0 (0%) | 0.050 |
| Sepsis/septic shock | 5 (24%) | 0 (0%) | 0.027 |
| Other infection | 4 (19%) | 0 (0%) | 0.050 |
| Steroid treatment at EI [n (%)] | 6 (29%) | 18 (95%) | <0.001 |
| Antibiotic treatment at EI [n (%)] | 11 (52%) | 6 (32%) | 0.139 |
| Ventilatory parameters at EBC collection | |||
| Respiratory frequency (min−1) | 13 [12; 15] | 12 [12; 12] | 0.001 |
| Tidal volume (mL·kg−1) | 8.0 [7.4; 8.2] | 7.4 [7.3; 7.7] | 0.023 |
| FiO2 (%) | 100 [85; 100] | 97 [96; 97] | 0.008 |
| PEEP (cm H2O) | 10 [10; 10] | 10 [10; 10] | 0.046 |
| Peak pressure (cm H2O) | 23 [22; 25] | 20 [19; 21] | 0.002 |
| Time from EI to EBC collection (h) | 10.9 [4.9; 18.3] | 0.0 [0.0; 0.0] | <0.001 |
Data are shown as median [IQR] or n (%). EBC: exhaled breath condensate; EI: endotracheal intubation; FiO2: fraction of oxygen in inspired air; IQR: interquartile range; PEEP: positive end-expiratory pressure.