Table 4. Multivariate analysis of prognostic factors associated with intubation.

	sHR	95% CI	p
Number of pulmonary quadrants on chest X-ray	1.73	[1.46–2.06]	<0.001
FiO2 >60% at HFNC initiation	3.12	[2.06–4.74]	<0.001
SAPS II at ICU admission	1.03	[1.02–1.05]	<0.01
Sp02 < 95% with FiO2 = 100% 15 minutes after HFNC initiation	2.05	[1.32–3.18]	0.0014
Absence of sepsis	0.32	[0.12–0.74]	0.0087

Allo-HSCT: allogenic hematopoietic stem cell transplantation, CI: confidence interval, HFNC: high flow nasal cannula, sHR: subdistribution Hazard ratio, SAPS II: simplified acute physiology score II.