Table 3.

Results of multivariate analyses for prediction of respiratory system compliance (A) and ventilatory ratio (B) at days 1 and 7

	CRS at day 1			CRS at day 7
	Estimate	Std. Error	p value	Estimate	Std. Error	p value
(A)
COVID-19 versus non-COVID-19	4.250	1.512	0.005	2.460	3.224	0.447
PEEP	0.726	0.180	< 0.001	0.671	0.300	0.027
PaO2/FiO2	0.020	0.009	0.020	0.057	0.018	0.002

	VR at day 1			VR at day 7
	Estimate	Std. Error	p value	Estimate	Std. Error	p value
(B)
COVID-19 versus non-COVID-19	− 0.691	0.117	< 0.001	− 0.135	0.263	0.608
PEEP	0.022	0.009	0.021	0.051	0.015	0.001
PaO2/FiO2	− 0.002	0.001	< 0.001	− 0.004	0.001	< 0.001
Heated humidifier versus HME	− 0.468	0.136	0.001	− 0.374	0.279	0.182

C_RS, respiratory system compliance; PEEP, positive end-expiratory pressure; VR, ventilatory ratio; PaO₂, partial pressure of arterial oxygen; FiO₂, fraction of inspired oxygen; HME, heat and moisture exchanger