Table 2.

“Do-not-intubate” orders in patients receiving noninvasive respiratory support in different studies

				“Do-not-intubate” orders criteria
Study	Pt. overall NIV/CPAP/HFNC (n)	Pt. DNI (%)	Setting	Clinical judgment	Patient refusal	Low predicted probability of hospital survival	Frailty	Comorbidity	Age	Disease severity
Franco et. [27]	678	4.1	PU	X	X
Aliberti et al.[28]	157	41.4	HDU		X	X	X	X
Di Domenico et al.[29]	90	30.0	RICU/ED					X	X	X
Faraone et al.[30]	50	50.0	CCU				X	X	X
Vaschetto et al.[31]	537	26.1	RICU		X		X	X
Menzella et al.[32]	79	22.8	PU					X	X
Ramirez et al.[33]	159	23.9	INCU					X	X
Messina et al.[25]	74	41.8	HDU		X		X	X		X

CCU, COVID-19 care unit; ED, emergency department; HDU, high-dependency unit; INCU, intermediate care unit; Pt, patients; PU, pulmonology unit; RICU, respiratory intermediate care unit.