Figures
- FIGURE 1
CONSORT flow chart.
- FIGURE 2
Comparison of mean individual raw data for diffusing capacity of the lung for nitric oxide (DLNO), diffusing capacity of the lung for carbon monoxide (DLCO), alveolar volume (VA), and permeability factor for NO (κNO) and permeability factor for CO (κCO) between MasterScreen and HypAir in 35 subjects measured sequentially in random order (HypAir-MasterScreen (HA-MS) or MasterScreen-HypAir (MS-HA)).
Tables
- TABLE 1
Participant characteristics stratified by test period
Variables MasterScreen-HypAir HypAir-MasterScreen Overall Participants, n (%) 22 (63) 13 (37) 35 (100) Sex, n (%) Male 11 (50) 6 (46) 17 (49) Female 11 (50) 7 (54) 18 (51) Age years 40.8±2.9 38.8±5.2 40.0±15.5 Height cm 175.5±2.5 172.8±2.7 174.5±10.1 Weight kg 73.2±11.3 63.5±12.1 69.6 ±12.4 BMI kg·m−2 23.7±2.7 21.1±2.2 22.7±2.8 Heart rate beats·min−1 71.6±11.2 68.5±10.9 70.5±11.0 SpO2 % 97.7±0.9 97.3±1.2 97.5±1.0 FEV1 MasterScreen z-score −0.01±0.91 −0.38±0.63 −0.15±0.82 FVC MasterScreen z-score 0.55±0.92 −0.02±0.61 0.34±0.85 FEV1 HypAir z-score 0.20±0.92 −0.22±0.70 0.04±0.86 FVC HypAir z-score 0.64±0.87 0.11±0.59 0.44±0.81 Data are presented as mean±sd, unless otherwise stated. BMI: body mass index; SpO2: oxygen saturation measured by pulse oximetry; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity.
- TABLE 2
Descriptive analysis of primary and secondary end-points between MasterScreen and HypAir
Variables MasterScreen HypAir Per cent difference Primary end-point DLNO mL·min−1·mmHg−1 121.30 (110.13 to 132.48) 145.73 (132.04 to 159.41) −16.5 (−17.8 to −15.1) Secondary end-points DLCO mL·min−1·mmHg−1 28.47 (25.81 to 31.13) 28.15 (25.46 to 30.84) 1.4 (−0.1 to 2.9) Alveolar volume L 5.80 (5.38 to 6.21) 6.28 (5.85 to 6.71) −8.0 (−8.9 to – 7.0) Breath-hold time s 6.28 (6.17 to 6.39) 5.93 (5.81 to 6.05) 6.2 (4.6 to 7.8) Inspiratory volume L 4.66 (4.28 to 5.04) 4.68 (4.31 to 5.05) −0.5 (−1.7 to 0.7) κNO s−1 −6.13 (−6.25 to −6.00) −7.23 (−7.44 to −7.02) −14.6 (−17.3 to −11.9) κCO s−1 −0.018 (−0.019 to −0.018) −0.022 (−0.022 to −0.021) −15.8 (−17.2 to −14.4) KNO mL·min−1·mmHg−1·L−1 20.8 (19.7 to 21.9) 23.1 (21.8 to 24.4) −9.3 (−10.4 to −8.1) KCO mL·min−1·mmHg−1·L−1 4.9 (4.6 to 5.1) 4.5 (4.2 to 4.7) 10.2 (8.6 to 11.9) ΔFANO ppm −38.3 (−38.9 to −37.7) −42.8 (−44.1 to −41.5) −9.4 (−12.8 to −6.0) ΔFACO % −0.11 (−0.12 to −0.11) −0.13 (−0.13 to −0.13) −10.9 (−12.4 to −9.4) NO, expired/inspired ratio 0.117 (0.107 to 0.127) 0.100 (0.090 to 0.110) 19.2 (13.9 to 24.6) O2, expired/inspired ratio 0.877 (0.870 to 0.884) 0.887 (0.873 to 0.900) −1.4 (−2.7 to −0.01) CO, expired/inspired ratio 0.470 (0.458 to 0.481) 0.475 (0.464 to 0.468) 1.3 (−0.2 to 2.8) He, expired/inspired ratio 0.737 (0.718 to 0.756) 0.683 (0.665 to 0.702) −10.1 (−10.9 to −9.3) Data are presented as mean (95% CI). DLCO: diffusing capacity of the lung for CO; DLNO: diffusing capacity of the lung for NO; κCO: permeability factor for CO; κNO: permeability factor for NO; KNO: transfer coefficient of the lung for NO; KCO: transfer coefficient of the lung for CO; FACO: fractional concentration of CO in the alveolar space; FANO: fractional concentration of NO in the alveolar space; ΔFACO (expired–inspired CO concentration); ΔFANO (expired–inspired NO concentration). Ratios of expired to inspired gas concentrations are also shown.
- TABLE 3
Mixed linear models on differences in DLNO and secondary end-points between MasterScreen and HypAir devices
Variables Coefficient 95% CI p-value Primary end-point DLNO mL·min−1·mmHg−1 24.0 21.7 to 26.3 <0.0001 Secondary end-points DLCO mL·min−1·mmHg−1 −0.03 −0.57 to 0.12 0.20 Alveolar volume L 0.48 0.45 to 0.52 <0.0001 Breath-hold time s −0.33 −0.42 to −0.24 <0.0001 Inspiratory volume L 0.008 −0.028 to 0.026 0.66 κNO s−1 −1.08 −1.21 to −0.94 <0.0001 κCO s−1 −0.0035 −0.004 to −0.003 <0.0001 KNO mL·min−1·mmHg−1·L−1 2.2 1.9 to 2.5 <0.0001 KCO mL·min−1·mmHg−1·L−1 −0.41 −0.46 to −0.37 <0.0001 ΔFANO ppm −4.40 −5.15 to −3.66 <0.0001 ΔFACO % −0.015 −0.016 to −0.013 <0.0001 NO, expired/inspired ratio −0.017 −0.012 to −0.014 <0.0001 O2, expired/inspired ratio 0.012 0.005 to 0.019 0.0014 CO, expired/inspired ratio −0.007 −0.012 to −0.002 0.0063 He, expired/inspired ratio −0.054 −0.058 to −0.050 <0.0001 Data are presented as mean (95% confidence interval). Positive coefficients means that HypAir gave larger measurements than MasterScreen. DLCO: diffusing capacity of the lung for CO; DLNO: diffusing capacity of the lung for NO; κCO: permeability factor for CO; κNO: permeability factor for NO; KNO: transfer coefficient of the lung for NO; KCO: transfer coefficient of the lung for CO; FACO: fractional concentration of CO from the alveolar space; FANO: fractional concentration of NO from the alveolar space; ΔFACO (expired–inspired CO concentration); ΔFANO (expired–inspired NO concentration). Ratios of expired to inspired gas concentrations are also shown.
- TABLE 4
Intrasession variability characteristics for MasterScreen and HypAir
Variables MasterScreen HypAir Measurement error# Repeatability¶ CV % ICC Measurement error# Repeatability¶ CV % ICC DLNO mL·min−1·mmHg−1 6.76 18.73 4.89 0.972 (0.952–0.985) 5.97 16.52 4.05 0.962 (0.934–0.979) DLCO mL·min−1·mmHg−1 1.16 3.22 3.80 0.986 (0.975–0.992) 0.97 2.70 3.38 0.981 (0.968–0.990) VA L 0.11 0.30 1.77 0.995 (0.992–0.997) 0.11 0.31 1.79 0.993 (0.987–0.996) Data were measured at a target breath-hold time of 5 s. CV: coefficient of variation; ICC: intraclass correlation coefficient; DLNO: diffusing capacity of the lung for NO; DLCO: diffusing capacity of the lung for CO; VA: alveolar volume. #: the measurement error (or within-subject standard deviation, SDws) was calculated by the root mean square method; ¶: repeatability of gas diffusing measurements was calculated as the SDws from all three single-breath tests separately and multiplied by 2.77 (95% level of confidence).
Supplementary Material
Please note: supplementary material is not edited by the Editorial Office, and is uploaded as it has been supplied by the author.
Supplementary material 00193-2021.SUPPLEMENT
