Table 1.
Patient´s baseline characteristics
| Entire population n = 2341 |
Successfully extubated n = 1936 |
Reintubated n = 405 |
p | |
|---|---|---|---|---|
| General characteristics | ||||
| Male, n (%) | 1433 | 1170 (60.4) | 263 (64.9) | 0.361 |
| Age, mean (± SD) | 60 (20.0) | 60 (20.0) | 62 (19.0) | 0.004 |
| APACHE II at ICU admission, mean (± SD)a | 16 (6.0) | 16 (6.0) | 18 (8.0) | < 0.001 |
| SARS COVID-19, no. (%)b | 334 | 274 (14.2) | 60 (14.8) | 0.789 |
| High risk factors for extubation failure, no. (%)c | ||||
| Hypercapnia at the end of the SBT | 127 | 86 (4.4) | 41 (10.1) | < 0.001 |
| Airway patency problems | 140 | 109 (0.1) | 31 (7.6) | 0.148 |
| Respiratory secretions | 332 | 248 (12.8) | 84 (20.7) | < 0.001 |
| Not simple weaning | 602 | 446 (23.0) | 156 (38.5) | < 0.001 |
| APACHE II > 12 at extubationa | 493 | 358 (18.5) | 135 (33.3) | < 0.001 |
| BMI > 30d | 379 | 272 (14.0) | 107 (26.4) | < 0.001 |
| CHARLSON index ≥ 2e | 963 | 764 (39.5) | 199 (10.3) | < 0.001 |
| Prolonged mechanical ventilation | 584 | 446 (23.0) | 138 (34.1) | < 0.001 |
| Acute cardiac failure | 190 | 138 (7.1) | 52 (12.8) | 0.001 |
| At least moderate COPD | 239 | 179 (9.2) | 60 (14.8) | 0.001 |
| Age > 65 y | 713 | 572 (29.5) | 141 (34.8) | 0.042 |
| Comorbidities, no. (%)e | ||||
| Chronic heart disease | 489 | 401 (20.7) | 88 (21.7) | 0.697 |
| COPD | 241 | 190 (9.8) | 51 (12.6) | 0.113 |
| Other respiratory diseases | 561 | 449 (23.2) | 112 (27.6) | 0.064 |
| Vascular diseases | 114 | 84 (4.3) | 30 (7.4) | 0.013 |
| Hepatic diseases | 175 | 125 (6.5) | 50 (12.3) | < 0.001 |
| Other diseases | 324 | 254 (13.1) | 70 (17.3) | 0.033 |
| Diagnosis at ICU admission, no. (%)g | ||||
| Primary respiratory failure | 1346 | 1092 (56.4) | 254 (62.7) | 0.023 |
| Primary non-respiratory failure | 1376 | 1150 (59.4) | 226 (55.8) | 0.200 |
| Trauma | 294 | 243 (12.5) | 51 (12.6) | 1 |
| Surgical procedure | 781 | 656 (33.9) | 125 (30.8) | 0.265 |
| Screening strategy, no. (%)f | ||||
| Conservative strategy | 1980 | 1633 (84.3) | 347 (85.7) | 0.533 |
| Aggressive strategy | 361 | 303 (15.6) | 58 (14.3) | |
| SBT, no. (%) | ||||
| T-tube trial | 382 | 345 (17.8) | 37 (9.1) | < 0.001 |
| Pressure support 5 cm H2O | 517 | 445 (22.9) | 72 (17.8) | |
| Pressure support 7 cm H2O | 1075 | 843 (43.5) | 232 (57.3) | |
| Pressure support 8 + PEEP 5 cm H2O | 367 | 304 (15.7) | 63 (15.6) | |
| Postextubation preventive therapy, no. (%) | ||||
| COT | 263 | 231 (11.9) | 32 (7.9) | 0.015 |
| HFNC | 1600 | 1325 (68.4) | 275 (68.0) | |
| NIV | 478 | 380 (19.6) | 98 (24.2) | |
| Three factors model predicting extubation failure, no. (%) | ||||
| Low risk patients | 1016 | 866 (44.7) | 150 (37.0) | 0.007 |
| High risk patients | 1325 | 1070 (55.3) | 255 (63.0) | |
| Four factors model predicting extubation failure, no. (%) | ||||
| Low risk patients | 802 | 702 (36.3) | 100 (24.7) | < 0.001 |
| High risk patients | 1539 | 1234 (63.7) | 305 (75.3) | |
| Eleven factors model predicting extubation failure, no. (%) | ||||
| Low risk patients | 673 | 609 (31.5) | 64 (15.8) | < 0.001 |
| High risk patients | 1668 | 1327 (68.5) | 341 (84.2) | |
APACHE II Acute Physiology and Chronic Health Evaluation II; BMI body mass index; COPD chronic obstructive pulmonary disease; COT conventional oxygen therapy; HFNC high flow nasal cannula; NIV noninvasive ventilation; PEEP positive end-expiratory pressure; SARS COVID-19 severe acute respiratory syndrome secondary to coronavirus disease 2019; SBT spontaneous breathing trial
aAPACHE II score was calculated from 17 variables. Scores range from 0 to 71 points, with higher scores indicating more severe disease
bSevere hypoxemic respiratory failure secondary to RT-PCR-confirmed COVID-19 pneumonia
cDefined according to references [12, 13]
dBody mass index calculated as weight in kilograms divided by height in meters squared
eComorbidities were categorized based on the Charlson Comorbidity Index (detailed in the online supplement). Fully detailed in Table S1
fScreening strategy defined according to the protocol reported in reference [8]
gThere can be more than one diagnosis