Control of the expiratory flow in a lung model and in healthy volunteers with an adjustable flow regulator: a combined bench and randomized crossover study

Table 3 Breathing characteristics of the volunteers

	Baseline (Mean ± STD)	Medium flow regulation (Mean ± STD)	High flow regulation (Mean ± STD)	Effect size medium flow regulation (MD, 95% CI)		Effect size high flow regulation (MD, 95% CI)		p
EFmax [ml·s⁻¹]	− 574 ± 131	− 395 ± 71	− 266 ± 58	180	[154, 205]	309	[283, 334]	< 0.001
R_AW [cmH₂O·L⁻¹·s⁻¹]	1.9 ± 0.2	8.5 ± 3.1	23.1 ± 9.3	6.6	[4, 9.1]	21.2	[18.6, 23.7]	< 0.001
P_AW mean [cmH₂O]	0.6 ± 0.1	2.9 ± 1.4	5.4 ± 2.4	2.2	[1.6, 2.9]	4.7	[4.1, 5.4]	< 0.001
P_AW max [cmH₂O]	1.1 ± 0.3	4.8 ± 2.4	7.7 ± 2.9	3.8	[2.9, 4.6]	6.7	[5.8, 7.5]	< 0.001
V_T [ml]	1050 ± 360	1100 ± 420	1080 ± 460	60	[− 40, 150]	40	[− 60, 130]	0.47
MV [L·min⁻¹]	11.6 ± 2.1	10.8 ± 2.1	9.1 ± 2.2	− 0.9	[− 0.3, − 1.4]	− 2.6	[− 2, − 3.1]	0.004
RR [min⁻¹]	12 ± 4	11 ± 4	10 ± 4	− 1	[− 2, 0]	− 3	[− 3, − 2]	0.011
T_In [s]	2.3 ± 1.0	2.3 ± 1.1	2.1 ± 1.0	0	[− 0.1, 0.2]	− 0.3	[− 0.4, − 0.1]	0.053
T_Ex [s]	3 ± 0.9	3.7 ± 1.3	5 ± 2.1	0.7	[0.3, 1.1]	2	[1.5, 2.4]	0.004
∆EELV [ml]	n.a	31 ± 458	320 ± 681	31	[− 159, 222]	320	[130, 511]	0.033

MD mean difference; CI confidence interval; EFmax maximal expiratory flow; R_AW airway resistance; P_AW airway pressure; V_T tidal volume; MV minute volume; RR respiratory rate; T_In inspiratory time; T_Ex expiratory time; ∆EELV change of the end-expiratory lung volume

ISSN: 1465-993X