Study | Study design | Study population | Primary outcome(s) | Location | Oxygen support | Prone protocol | Main finding(s) |
---|---|---|---|---|---|---|---|
Caputo et al.6 | Single-centre prospective cohort study | n = 50 Baseline Spo2 before PP: median 84% (IQR 75%–90%) | Change in oxygenation (Spo2), rate of intubation in first 24 h of presentation to ED | ED | NRB (38 of 50 patients, 76%) or HFNC (12 of 50 patients, 24%) | Five minutes of PP without change in oxygen delivery |
|
Elharrar et al.1 | Prospective before–after study, single centre | n = 24 Baseline Pao2: mean 72.8 (SD 14.2) mm Hg | Increase in Pao2 ≥ 20% of baseline | Medical ward | 16 of 24 patients (67%) on NC < 4 L/min; 8 of 25 patients (33%) on NC ≥ 4 L/min or HFNC | Single episode of PP; duration determined by comfort |
|
Sartini et al.3 | Single-centre cross-sectional study | n = 15 Baseline Pao2/Fio2: mean 157 (SD 43) mm Hg | Change in oxygenation and respiratory vital signs | Medical ward | NIV | Cycles of PP: median 2 (IQR 1–3) for a median duration of 3 (IQR 1–6) h | |
Coppo et al.24 | Single-centre prospective cohort study | n = 56 Baseline Pao2/Fio2: mean 180.5 (SD 76.6) mm Hg | Change in supine Pao2/Fio2 after episode of PP | Medical ward, ED, HDU | CPAP (44 of 56 patients, 79%), reservoir mask (9 of 56 patients, 16%), Venturi mask (3 of 56 patients, 5%) | Minimum 3 h, up to 8 h depending on comfort; 25 patients maintained > 3 h |
|
Winearls et al.25 | Single-centre retrospective cohort study | n = 24 Baseline Pao2/Fio2 on CPAP: mean 143 (SD 73) mm Hg | Change in respiratory vital signs, tolerance and duration of PP | HDU | CPAP | PP initiated median 30 (IQR 7–99) h after CPAP; mean duration of PP in first 24 h: 8 (SD 5) h, continued for 10 (SD 5) d |
|
Solverson et al.26 | Multicentre retrospective cohort study | n = 17 Baseline Pao2/Fio2: median 152 (IQR 97–233) mm Hg | Tolerance of PP, physiologic and clinical outcomes | Medical ward, ICU | NC, NRB, HFNC | Median no. of daily PP sessions 2 (IQR 1–6) with a median duration of 75 (IQR 30–480) min for first session |
|
Ferrando et al.27 | Multicentre prospective cohort study | n = 199; 144 patients received only HFNC and 55 received HFNC + PP | Physiologic and clinical outcomes, including intubation risk | ICU | HFNC | PP was considered only if duration was > 16 h/d, regardless of the no. of sessions |
|
Note: CPAP = continuous positive airway pressure, ED = emergency department, Fio2 = fractional concentration of oxygen in inspired air, HDU = high dependency unit, HFNC = high-flow nasal cannula, ICU = intensive care unit, IQR = interquartile range, NC = nasal cannula, NIV = noninvasive ventilation, NRB = nonrebreather high-flow oxygen mask, Pao2 = arterial partial pressure of oxygen, PP = prone positioning, RR = respiratory rate, SD = standard deviation, Spo2 = peripheral oxygen saturation of hemoglobin.
↵* Exact data not available.