Table 2. Performance of the automated stretching system on human bronchi.

	Overall duration of cyclic stretching	n	Differences between measured and preset values
			g	%
Tbaseline
	5 min	9	0.47±0.09**	178±28
First series	20 min	10	0.58±0.09**	164±12
	40 min	10	0.52±0.09**	161±12
	60 min	10	0.37±0.09**	156±21
Second series (validation)	60 min	79	0.42±0.05**	160±10
Tmax
	5 min	9	-0.53±0.27*	87±10
First series	20 min	10	-0.19±0.29	96±11
	40 min	10	0.00±0.21	109±8
	60 min	10	0.23±0.26	115±10
Second series (validation)	60 min	79	0.06 ±0.06	106±3
Tension variation (Tmax—Tbaseline)
	5 min	9	0.84±0.12**	43±9
First series	20 min	10	0.35±0.15*	52±9
	40 min	10	0.15±0.22	58±12
	60 min	10	0.13±0.21	88±21
Second series (validation)	60 min	79	0.14±0.13	55±5

Data are shown as the mean ± SEM. The imposed tension was measured every 0.1 sec with a dedicated software package (IOX, version 2.4.2, EMKA Technologies, Paris, France). The magnitude of the stretch generated by the system corresponded to the difference between 80% T_max and T_baseline (Fig 2). The expected tension variation generated by the device (80% T_max—T_baseline) was compared to the observed values generated by the bronchial rings (maximum tension—minimum tension) in response to the forces imposed by the device (Fig 2).

*P <.01

**P <.001 when comparing measured and preset values.