Table 1 Characteristics of the studies included in the meta-analysis
Study | Design | Sample size | Age (years) | Type of patients | PaO2/FiO2 at baseline (mmHg) | MV before randomization (h) | Intervention | Comparator | APRV initial setting | Primary outcome |
|---|---|---|---|---|---|---|---|---|---|---|
Putensen et al. [13] | RCT | 30 | APRV: 40 ± 19 CV: 42 ± 23 | Trauma with acute respiratory failure | 250 | APRV: 6 ± 3.9 CV: 6 ± 3.9 | APRV | PCV | Ph = ↓UIP Vt < 7 ml/kg Pl = LIP + 2 cmH2O Tl = flow 0 | Effects on cardiorespiratory function |
Varpula et al. [10] | RCT | 58 | APRV: 50 (38.5–60.5) CV: 44 (35.5–53) | ALI/ARDS P/F < 200 mmHg MV < 72 h | APRV: 150 ± 8 CV: 164 ± 7 | 39.1 ± 17.5 | APRV | SIMV-PC/PS | Ph = ↓UIP Pl = ↑LIP Th = 4 s Tl = 1 s | Ventilator-free days at day 28 |
Li et al. [12] | RCT | 52 | APRV: 54.3 ± 8.4 CV: 53.6 ± 9.5 | Moderate/severe ARDS | APRV: 119 ± 35 CV: 118 ± 36 | Not reported | APRV | SIMV (LTV) | Ph = 30 cmH2O Pl = 0 Th = 4–8 s Tl = 0.4–0.8 s | Unclear |
Zhou et al. [11] | RCT | 138 | APRV: 51.5 ± 15 CV: 52 ± 15.1 | ARDS P/F < 250 mmHg MV < 48 h | APRV: 122 ± 47 CV: 138 ± 56 | APRV: 24.6 ± 12.6 CV: 22.1 ± 13.5 | APRV | LTV | Ph = Pplat Pl = 5 cmH2O Tl > 50% PEFR RR 10–14 bpm MVst = 30% of MVtot | Ventilator-free days at day 28 |
Hirshberg et al. [16] | RCT | 52 | APRV: 57 ± 16 APRV-LTV: 57 ± 15 VC-LTV: 51 ± 14 | Hypoxemic respiratory failure MV < 24 h | APRV: 109 ± 67 CV: 121 ± 50 | Not reported | APRV/APRV-LTV | VC-LTV | Ph = Pplat Pl = 5 cmH2O Th = 4–6 s Tl = 50–75% PEFR | P/F at day 3 |