TABLE 1

Prone positioning in non-intubated, non-coronavirus disease 2019 patients

First author [ref.]	Patients n	Diseases	Respiratory device	PP regimen	Main results	Adverse event	Comments
Chaisupamongkollarp [19]	17	Pneumonia	Oxygen		Improve S_pO₂ Improve compliance		Paediatric
Tulleken [20]	1	Pneumonia	HFNC	20 h	Improve P_aO₂ Resolve opacities	0	Paediatric
Valter [21]	4	CHF, pneumonia, ARDS	0	1–5 h	Improve P_aO₂ Avoid intubation	0	1 death (CHF)
Feltracco [22]	2	Post-reimplantation syndrome	NIV	6–8 h per day, 8–10 days	Decrease F_IO₂ NIV removal	0
Feltracco [23]	3	Lung transplant respiratory complications	HFPV	1–3 h, 3–6 times per day	Improve secretions clearance Improve respiratory mechanic Attenuate graft infiltrates Improve gas exchange	0
Scaravilli [24]	15	Hypoxaemic acute respiratory failure (pneumonia, fascitis, sepsis)	HFNC, CPAP and NIV	3 h per day, 2 days	Improve P_aO₂	Intolerance (n=2)	Retrospective P_aO₂ return to baseline after resupination
Ding [25]	20	Infectious, moderate-to-severe ARDS (pneumonia, influenza)	NIV and HFNC	30 min twice per day, ≥3 days	Avoid intubation Improve P_aO₂/F_IO₂	Intolerance (n=2)	Intubation in 78% of severe ARDS patients
Pérez-Nieto [26]	6	Non-infectious, severe ARDS (thoracic trauma, lupus pneumonitis)	NIV and HFNC	2–3 h per 12 h, 2 days	Avoid intubation	0	Retrospective

PP: prone positioning; S_pO₂: oxygen saturation measured by pulse oximetry; HFNC: high-flow nasal cannula; P_aO₂: arterial oxygen tension; CHF: congestive heart failure; ARDS: acute respiratory distress syndrome; NIV: noninvasive ventilation; F_IO₂: inspiratory oxygen fraction; HFPV: high-frequency percussive ventilation; CPAP: continuous positive airway pressure.