Table 1 Patient characteristics by quartile of the timing of tracheostomy
|  | Q1 Tracheostomy ≤ 6 days (n = 446) | Q2 Tracheostomy 7–10 days (n = 405) | Q3 Tracheostomy 11–14 days (n = 323) | Q4 Tracheostomy > 14 days (n = 364) | p value |
|---|---|---|---|---|---|
Age, years | 70 (60–77) | 70 (62–78) | 70 (59–78) | 70 (60–77) | 0.658 |
Sex, male | 308 (69.1%) | 259 (64.0%) | 207 (64.1%) | 231 (63.5%) | 0.277 |
Body mass index, kg/m2 | 21.6 (18.7–24.6) | 21.8 (19.0–24.3) | 22.0 (19.3–25.0) | 22.1 (19.5–25.0) | 0.176 |
Comorbidity | |||||
 Chronic heart failure | 5 (1.1%) | 5 (1.2%) | 5 (1.5%) | 14 (3.8%) | 0.035 |
 Chronic respiratory failure | 26 (5.8%) | 15 (3.7%) | 11 (3.4%) | 8 (2.2%) | 0.065 |
 Chronic liver disease | 7 (1.6%) | 6 (1.5%) | 4 (1.2%) | 5 (1.4%) | 0.991 |
 Malignancy | 24 (5.4%) | 23 (5.7%) | 17 (5.3%) | 22 (6.0%) | 0.971 |
 Immunodeficiency | 40 (9.0%) | 37 (9.1%) | 43 (13.3%) | 43 (11.8%) | 0.158 |
 Maintenance dialysis | 12 (2.7%) | 14 (3.5%) | 25 (7.7%) | 26 (7.1%) | 0.001 |
Emergency admission | 384 (86.1%) | 360 (88.9%) | 283 (87.6%) | 299 (82.4%) | 0.063 |
Surgical type of admission | 172 (38.6%) | 158 (39.0%) | 124 (38.4%) | 177 (48.6%) | 0.010 |
Systematic diagnosis for ICU admission | |||||
 Cardiac | 63 (14.1%) | 80 (19.8%) | 88 (27.2%) | 162 (44.5%) |  < 0.001 |
 Respiratory | 142 (31.8%) | 109 (26.9%) | 65 (20.1%) | 77 (21.2%) | |
 Gastrointestinal | 38 (8.5%) | 51 (12.6%) | 39 (12.1%) | 49 (13.5%) | |
 Neurological | 133 (29.8%) | 103 (25.4%) | 66 (20.4%) | 33 (9.1%) | |
 Sepsis | 8 (1.8%) | 11 (2.7%) | 13 (4.0%) | 10 (2.7%) | |
 Trauma | 37 (8.3%) | 41 (10.1%) | 27 (8.4%) | 17 (4.7%) | |
 Other diagnosis | 25 (5.6%) | 10 (2.5%) | 25 (7.7%) | 16 (4.4%) | |
APACHE II score | 22 (17–28) | 23 (19–29) | 24 (19–31) | 22 (18–28) | 0.003 |
Data within 24Â h after ICU admission | |||||
 Incidence of AKI | 20/446 (4.5%) | 23/404 (5.7%) | 43/323 (13.3%) | 43/363 (11.8%) | < 0.001 |
 Lowest PaO2:FiO2 | 226 (154–320) | 199 (133–293) | 194 (125–291) | 172 (117–236) | < 0.001 |
 GCS score | 12 (6–15) | 11 (6–15) | 13 (6–15) | 15 (10–15) | < 0.001 |
Length of hospital stay before ICU admission, days | 1 (0–6) | 1 (0–4) | 1 (0–6) | 1 (0–5) | 0.686 |