Home noninvasive positive pressure ventilation with built-in software in stable hypercapnic COPD: a short-term prospective, multicenter, randomized, controlled trial

Figures & data

Figure 1 Scatter plot of leak recorded in built-in software.

Abbreviations: MV, minute volume; Vt, tidal volume; BPM, breath per minuter; IT, inspiratory time.

Figure 2 Parameters recorded in built-in software.

Abbreviations: MV, minute volume; Vt, tidal volume; BPM, breath per minuter; IT, inspiratory time.

Table 1 Baseline demographic and clinical characteristics of patients

	NPPV + LTOT	LTOT
Male, n (%)	36 (80)	35 (77.78)
Age, years	66.91±7.10	68.47±6.57
BMI, kg/m^2	19.43±3.10	20.56±3.36
SaO2, %	90.80±4.61	92.44±3.11
IPAP, mmH2O	17.8±2.08	–
EPAP, mmH2O	4.2±0.1	–
ΔPS, mmH2O	12.29±2.08	–
pH	7.37±0.04	7.36±0.05
PaCO2, mmHg	57.78±2.88	58.07±3.50
PaO2, mmHg	69.76±15.83	73.99±27.85
FVC, L	1.60±0.65	1.48±0.53
FVC, % predicted	51.16±16.45	50.26±17.28
FEV1, L	0.55±0.19	0.62±0.22
FEV1, % predicted	23.34±7.48	28.02±11.97
FEV1/FVC, %	37.56±9.66	38.05±17.36

Notes: Data are mean ± SD, unless otherwise stated. ΔPS= IPAP-EPAP.

Abbreviations: BMI, body mass index; EPAP, expiratory positive airway pressure; FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; IPAP, inspiratory positive airway pressure; LTOT, long-term oxygen therapy; NPPV, noninvasive positive pressure ventilation; PaO₂, arterial oxygen pressure; PaCO₂, arterial carbon dioxide pressure; SaO₂, arterial oxygen saturation.

Figure 3 CONSORT flow diagram.

Abbreviations: CONSORT, consolidated standards of reporting trials; LTOT, long-term oxygen therapy; NPPV, noninvasive positive pressure ventilation.

Figure 4 Bland-Altman plots for absolute reliability of parameters estimation between the Flexo and LabChart.

Notes: (A) Bland–Altman plots for absolute reliability (means vs differences) of leak estimation between the Flexo and LabChart. (B) Bland–Altman plots for absolute reliability (means vs differences) of pressure estimation between the Flexo and LabChart.
Abbreviation: SD, standard deviation.

Table 2 6MWD

Group	6MWD change, n		Total
	Improved (Δd ≥54 min)	Unimproved (Δd <54 min)
LTOT	10	48	58
NPPV + LTOT*	21	36	57
Total	31	84	115

Note:

* Chi-square test, P=0.02.

Abbreviations: LTOT, long-term oxygen therapy; 6MWD, 6-min walk distance; NPPV, noninvasive positive pressure ventilation.

Table 3 Treatment period effect between two groups

	90 days change from baseline (95% confidence interval)		Difference	P-value
	NPPV + LTOT	LTOT
SaO2	1.2% (−0.8% to 3.2%)	0.3% (−0.8% to 1.5%)	0.9% (−0.6% to 2.4%)	0.15
FVC	6.6% (−6.4% to 18.6%)	6.7% (0.6% to 12.8%)	−0.1% (−5.6% to 23.1%)	0.20
FEV1	17.3% (−8.5% to 43.2%)	−1.4% (−7.7% to 5.0%)	18.7% (−5.4% to 33.6%)	0.10
pH	0.002 (0 to 0.003)	0.002 (0 to 0.004)	−0.001 (0.001 to 0.002)	0.56
PaCO2	−17.7% (−21.5% to −13.9%)	−7.2% (−9.7% to −5.7%)	−10.5% (−4.7% to −12.3%)	0.03
PaO2	4.3% (−4.6% to 13.2%)	−3.1% (−9.6% to 3.5%)	7.4% (−5.4% to 4.1%)	0.58
SRI	24.7% (15.3% to 34.1%)	5.5% (−0.9% to 11.9%)	19.2% (2.1% to 17.6%)	0.21
CAT	−14.7% (−21.3% to −10.2%)	−11.9% (−18.3% to −5.5%)	6.8% (−20.3% to −4.2%)	0.06
TDI	−6.9% (9.6% to −4.2%)	−9.4% (−11.9% to −6.9%)	2.5% (5.3% to −3.2%)	0.79

Abbreviations: CAT, COPD assessment test; FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; LTOT, long-term oxygen therapy; NPPV, noninvasive positive pressure ventilation; PaO₂, arterial oxygen pressure; PaCO₂, arterial carbon dioxide pressure; SaO₂, arterial oxygen saturation; SRI, Severe Respiratory Insufficiency; TDI, Transitional Dyspnea Index.