Table 1.
Characteristics of the study population of N = 312 mechanically ventilated children. Data are presented as median (25–75 interquartile range) or percentage (%) of total. Ventilator-free days (VFD) through day 28 were defined as the number of days within 28 days that a patient was alive and free of mechanical ventilation [16]. Patients were assigned 0 VFD if they remained intubated or died prior to day 28 without remaining extubated for more than 24 h. *Denotes p < 0.005 (Kruskal Wallis test). PRISM Pediatric Risk of Mortality; OI oxygenation index
| Patient stratification by Pediatric Mechanical Ventilation Consensus Conference category | ||||
|---|---|---|---|---|
| Normal respiratory system mechanics | Restrictive respiratory system mechanics (i.e., reduced compliance) | Mixed respiratory system mechanics (i.e., reduced compliance and increased resistance) | Cardiac (combination of normal and altered respiratory system mechanics) | |
| N = 84 | N = 69 | N = 78 | N = 81 | |
| Baseline patient characteristics | ||||
| Age (months) * | 49.3 (9.4–122.0) | 23.1 (8.0–46.0) | 2.0 (1.2–8.5) | 2.2 (0.5–6.7) |
| ≤ 12 months (%) | 29.78 | 39.1 | 84.6 | 84.0 |
| 13–60 months (%) | 20.2 | 34.8 | 11.5 | 6.2 |
| > 60 months (%) | 50.0 | 26.1 | 3.8 | 9.9 |
| Male gender (%) | 61.9 | 58.0 | 62.8 | 63.0 |
| Weight (kg) * | 16.5 (8.0–29.5) | 12.4 (8.5–17.5) | 5.0 (4.0–6.7) | 4.2 (3.6–6.9) |
| PRISM III 24 h score | 8.5 (5.0–14.0) | 10.0 (6.0–15.0) | 11.0 (8.0–15.0) | 12.0 (7.0–15.5) |
| PARDS (%) | 0.0 | 5.8 | 24.4 | 1.2 |
| Cstat (cmH2O/L/kg) * | 0.59 (0.43–0.78) | 0.55 (0.39–0.73) | 0.34 (0.28–0.44) | 0.5 (0.32–0.6) |
| Baseline ventilator settings | ||||
| PIP (cmH2O) * | 18 (16–22) | 20 (17–23) | 27 (24–29) | 20 (18–23) |
| Pplat (cmH2O) * | 16 (14–19) | 17 (15–21) | 24 (21–26) | 18 (16–21) |
| PEEP (cmH2O) * | 5 (5–6) | 5 (5–6) | 6 (5–7) | 5 (5–6) |
| Vt-exp (mL/kg) * | 7.6 (6.6–8.6) | 7.6 (6.5–8.5) | 6.6 (6.1–7.7) | 7.5 (6.8–8.3) |
| Inspiratory time (s) * | 0.75 (0.62–0.9) | 0.7 (0.6–0.75) | 0.55 (0.5–0.6) | 0.55 (0.5–0.6) |
| Mandatory breath rate (/min) * | 22 (17–30) | 23 (20–30) | 40 (32–40) | 35 (29–40) |
| Outcome data | ||||
| Ventilation time (h) * | 88.3 (42.5–163.4) | 69.8 (25.3–179.3) | 107.5 (78.0–152.2) | 91.5 (32.6–163.1) |
| VFD day 28 | 24 (20–26) | 24 (19–26) | 23 (21–24) | 24 (21–26) |
| PICU mortality (%) | 6.0 | 4.3 | 2.6 | 3.7 |