Table 1.
Demographic and clinical characteristics according to the presence or absence of pneumothorax
| Variable | No pneumothorax | Pneumothorax | p value |
| Number of patients (%) | 36 (88) | 5 (12) | |
| Gender (male/female) | 26/10 | 4/1 | 1 |
| Age, years | 76.3 ± 10.4 | 68.8 ± 18.0 | 0.46 |
| Body weight, kg | 58.5 ± 12.4 | 57.0 ± 18.2 | 0.98 |
| APACHE II score | 20.7 ± 6.6 | 26.0 ± 11.8 | 0.41 |
| Pre-existing comorbidities | |||
| Chronic renal insufficiency | 4 | 0 | 1 |
| Congestive heart failure | 9 | 2 | 0.59 |
| Diabetes mellitus | 15 | 2 | 1 |
| Chronic obstructive pulmonary disease | 5 | 0 | 1 |
| Pulmonary tuberculosis | 2 | 2 | 0.06 |
| Cerebrovascular disease | 17 | 1 | 0.37 |
| On ICU admission | |||
| Baseline lung injury score | 1.27 ± 1.04 | 1.59 ± 0.59 | 0.35 |
| Baseline respiratory rate | 25.32 ± 7.53 | 36.00 ± 5.10 | 0.006 |
| Baseline PaO2/FiO2 ratio | 289.9 ± 172.9 | 272.6 ± 140.8 | 0.87 |
| Baseline PaCO2 | 35.7 ± 9.3 | 49.4 ± 23.0 | 0.20 |
| During hospitalization | |||
| Highest lung injury score | 1.59 ± 1.10 | 2.51 ± 0.29 | 0.09 |
| Highest respiratory rate | 34.65 ± 5.19 | 40.80 ± 7.08 | 0.06 |
| Lowest PaO2/FiO2 ratio | 210.1 ± 123.8 | 65.8 ± 24.3 | 0.02 |
| Highest PaCO2 | 49.9 ± 17.4 | 80.1 ± 12.3 | 0.004 |
| ALI/ARDS (%) | 24 (66%) | 4 (80%) | 1 |
| Liberation from ventilator (%) at 30 days | 11(31) | 0 | 0.29 |
Data are presented as mean ± standard deviation. ALI, acute lung injury; APACHE, Acute Physiology and Chronic Health Evaluation; ARDS, acute respiratory distress syndrome; FiO2, fraction of inspired oxygen; ICU, intensive care unit; PEEP, positive end-expiratory pressure.