Background
Methods
Study design and participants
Weaning procedure
Clinical assessment of ICU-acquired weakness
Outcome
Statistical analysis
Results
Study population
Factors associated with extubation failure
Variables | Extubation success (N = 288) | Extubation failure (N = 56) | p value |
---|---|---|---|
Characteristics of the patients at admission | |||
Age, years | 67 ± 14 | 70 ± 12 | 0.1068 |
Male sex, n (%) | 172 (60%) | 37 (66%) | 0.3733 |
Body-mass index, kg/m2 | 28 ± 7 | 27 ± 5 | 0.4739 |
SAPS II at admission, points | 47 ± 18 | 55 ± 20 | 0.0042 |
Underlying chronic cardiac disease, n (%) | 153 (53%) | 24 (43%) | 0.1595 |
- Ischemic cardiopathy, n | 83 | 15 | |
- Left ventricular dysfunction, n | 66 | 12 | |
- Atrial fibrillation, n | 58 | 11 | |
- History of cardiogenic pulmonary edema, n | 29 | 4 | |
Underlying chronic lung disease, n (%) | 84 (29%) | 15 (27%) | 0.7188 |
- Chronic obstructive pulmonary disease, n | 58 | 13 | |
- Non-obstructive pulmonary disease, n | 26 | 2 | |
Main reason for intubation | 0.9180 | ||
- Acute respiratory failure, n (%) | 130 (45%) | 27 (48%) | |
- Coma, n (%) | 56 (19%) | 8 (14%) | |
- Shock, n (%) | 36 (13%) | 8 (14%) | |
- Cardiac arrest, n (%) | 12 (4%) | 2 (4%) | |
- Surgery, n (%) | 54 (19%) | 11 (20%) | |
Characteristics at time of extubation | |||
SBT performed using T-piece, n (%) | 148 (51%) | 30 (54%) | 0.7649 |
SBT performed using low levels of pressure-support, n (%) | 140 (49%) | 26 (48%) | 0.7649 |
Median duration of MV prior to extubation, days | 6 [3–12] | 8 [5–15] | 0.0208 |
Duration of MV > 7 days prior to extubation, n (%) | 125 (43%) | 30 (54%) | 0.1617 |
MRC (Medical Research Council) score, points | 49 ± 13 | 41 ± 16 | < 0.001 |
Limb weakness (MRC sum-score < 48), n (%) | 99 (34%) | 31 (55%) | 0.0036 |
- Moderate limb weakness (36 ≤ MRC sum-score < 48), n (%) | 53 (18%) | 12 (21%) | 0.5966 |
- Severe limb weakness (MRC sum-score < 36), n (%) | 46 (16%) | 19 (34%) | 0.0022 |
Ineffective cough, n (%) | 16 (6%) | 11 (20%) | 0.0008 |
Abundant secretions, n (%) | 87 (30%) | 25 (45%) | 0.0301 |
Patients with effective cough and without ICU-acquired weakness, n (%) | 184 (64%) | 24 (43%) | < 0.001 |
Prophylactic non-invasive ventilation after extubation, n (%) | 173 (60%) | 40 (71%) | 0.1035 |
Outcomes | |||
- Median duration of mechanical ventilation, days | 6 [3–12] | 18 [13–28] | < 0.001 |
- Median length of ICU stay, days | 11 [6–18] | 24 [16–37] | < 0.001 |
- ICU mortality, n (%) | 6 (2%) | 26 (26%) | < 0.001 |
Multivariate analysis
Variables | Adjusted odds ratio* [95% confidence interval] | p value |
---|---|---|
Model A entering MRC sum-score as continuous variable (R2 = 0.079) | ||
SAPS II at admission—for each point increase | 1.02 [1.01–1.04] | 0.0233 |
Ineffective cough | 2.72 [1.11–6.62] | 0.0281 |
MRC sum-score—for each point lost | 1.03 [1.01–1.05] | 0.0067 |
Model B entering MRC according to MRC sum-score < 48 (ICU-acquired weakness) or ≥ 48 (reference) (R2 = 0.069) | ||
SAPS II at admission—for each point increase | 1.02 [1.01–1.04] | 0.0121 |
Ineffective cough | 3.04 [1.27–7.29] | 0.0127 |
ICU-acquired limb weakness (MRC sum-score < 48) | 1.89 [1.02–3.48] | 0.0426 |
Model C entering MRC according to moderate, severe or no weakness (MRC sum-score ≥ 48 as reference) (R2 = 0.071) | ||
SAPS II at admission—for each point increase | 1.02 [1.01–1.04] | 0.0164 |
Ineffective cough | 2.90 [1.19–7.00] | 0.0187 |
Moderate weakness (48 < MRC sum-score ≥ 36) | 1.60 [0.74–3.47] | 0.2342 |
Severe weakness (MRC sum-score < 36) | 2.19 [1.06–4.54] | 0.0351 |