Table 3.
Variables associated with weaning failure in 246 mechanically ventilated patients (three patients could not be classified according to the international conference consensus definition)
| Variables | Weaning success (n = 173) | Weaning failure (n = 73) | p value |
|---|---|---|---|
| Male gender | 98 (57%) | 49 (67%) | 0.13 |
| Age (years) | 61 [52–73] | 69 [60–79] | 0.006 |
| Body mass index (kg/m2) | 26 [22–29] | 27 [22–32] | 0.07 |
| SAPS II at ICU admission | 49 [38–62] | 49 [39–65] | 0.73 |
| Comorbidities | |||
| COPD | 23 (13%) | 23 (32%) | 0.001 |
| Cardiac disease | 101 (58%) | 55 (75%) | 0.01 |
| Main reason for intubation | |||
| Coma | 54 (31%) | 9 (12%) | 0.002 |
| Acute respiratory failure | 48 (27%) | 39 (53%) | < 0.001 |
| Septic shock | 24 (14%) | 8 (11%) | 0.54 |
| Others | 47 (27%) | 17 (23%) | 0.53 |
| From ICU admission to first SBT | |||
| ARDS | 28 (16%) | 27 (37%) | < 0.001 |
| Neuromuscular blockade | 26 (15%) | 28 (38%) | < 0.001 |
| Septic shock | 61 (35%) | 39 (53%) | 0.01 |
| VAP | 17 (10%) | 16 (22%) | 0.01 |
| Supra-ventricular arrhythmias | 32 (19%) | 22 (30%) | 0.04 |
| Duration of MV before first SBT | 3 [2–6] | 6 [3–12] | < 0.001 |
| Dialysis | 22 (13%) | 8 (11%) | 0.70 |
| Fluid balance between ICU admission and first SBT (L) | 2.8 [0.9–6.4] | 5.7 [0.7–11.4] | 0.01 |
| Biological and ultrasound data at first SBT | |||
| PaO2/FiO2 ratio (mmHg) | 307 [242–385] | 247 [200–299] | < 0.001 |
| Moderate-to-large pleural effusion | 42 (24%) | 37 (51%) | < 0.001 |
| Drainable pleural effusion | 36 (21%) | 29 (40%) | 0.002 |
| Large pleural effusion | 21 (12%) | 25 (34%) | < 0.001 |
| Left ventricle ejection fraction (%, n = 205) | 60 [50–60] | 55 [40–60] | 0.06 |
| Outcome | |||
| Pleural effusion drainage during weaning | 0 | 4 (6%) | 0.01 |
| Prophylactic NIV post-extubation | 65 (38%) | 30 (44%) | 0.35 |
| Tracheotomy | 1 (1%) | 5 (7%) | 0.01 |
| VFD from first SBT to day 28 (days) | 23 [20–26] | 11 [0–21] | < 0.001 |
| Death in ICU | 5 (3%) | 19 (26%) | < 0.001 |
| Death at day 28 | 8 (5%) | 17 (23%) | < 0.001 |
Values are indicating number (%), or median [1st–3rd quartile]
SAPS II simplified acute physiology score, COPD chronic obstructive pulmonary disease, ARDS acute respiratory distress syndrome, VAP ventilator-associated pneumonia, SBT spontaneous breathing trial, NIV noninvasive ventilation, ICU intensive care unit, VFD ventilator-free days