Table 3. Serial changes in physiological variables after HFNC therapy between SF₄₈-improved group and SF₄₈-nonimproved group.

Variables	SF48-improved group, n=44					SF48-nonimproved group, n=47
	Baseline	At 12h	At 24h	At 48h		Baseline	At 12h	At 24h	At 48h
Respiratory rate (breaths/min)	26.91±6.01	24.11±4.87*	23.11±5.27*	23.20±4.33*		26.30±6.00	26.06±4.64	26.66±5.14	25.94±6.27
Heart rate (beats/min)	102.55±20.99	98.32±20.89*	95.84±17.10*	92.68±17.80*		102.77±20.56	98.51±18.87	103.28±23.64	103.57±22.01
SpO2/FiO2 ratio	141.77±37.47	146.64±39.62	155.61±39.04*	175.77±46.37*		157.34±39.93	144.34±29.98*	131.06±27.70*	121.94±33.10*

*, P<0.05: significant change from baseline values. HFNC, high-flow nasal cannula.