Differences in respiratory oscillometry measurements using mouthpiece, mouth, and nasal mask in healthy adults

• Published in: Journal of applied physiology (1985) Vol. 134; no. 1; pp. 142 - 146
• Main Authors: Alshlowi, Malak, Hakizimana, Ali, Alraimi, Afnan, Devani, Pooja, Lundblad, Lennart K A, Beardsmore, Caroline S, Gaillard, Erol A
• Format: Journal Article
• Language: English
• Published: United States 01.01.2023
• Subjects: Adult; Airway Resistance; Female; Humans; Lung; Mouth; Oscillometry - methods; Prospective Studies; Spirometry; asthma; lung function; wheeze; airway resistance
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00491.2022

Airway resistance measurements using oscillometry provide a potential alternative to spirometry in assessing airway obstruction and dynamics due to measurements taken during tidal breathing. Oscillometry typically requires participants to form a tight seal around a mouthpiece that can prove challenging for some people. To address this challenge, we conducted a prospective study to evaluate the effect of different interfaces like mouthpiece, mouth mask, and nasal mask on respiratory impedance results from oscillometry in a cohort of healthy adults. Ten healthy adults [7 females; mean age: 38.9 yr (SD ±15.5)] underwent oscillometry using each of the three interfaces. We measured resistance at 5 Hz (Rrs ), frequency dependence of resistance at 5-20 Hz (Rrs ), and reactance area (Ax). Rrs was not different when using the mouthpiece compared with the mouth mask [mean 2.98 cmH O/L/s (SD ±0.68) vs. mean 3.2 cmH O/L/s (SD ±0.81); = 0.92; 95% CI -0.82 to +0.38], respectively. Nasal mask Rrs measurements were significantly higher than mouthpiece measurements (mean 7.31 cmH O/L/s; SD ±2.62; < 0.01; 95%CI -6.91 to -1.75). With Ax , we found a mean of 4.01 cmH O/L (SD ±2.04) with the mouth mask compared with a mean of 4.02 cmH O/L (SD ±1.87; = 1.0 95% CI -1.86 to +1.87) for the mouthpiece, however, we found a significant difference between the mouthpiece and nasal mask for Ax (mean = 10.71; SD ±7.0 H O/L; = 0.04, 95% CI -12.96 to -0.43). Our findings show that oscillometry using a mouth mask may be just as effective as using a mouthpiece in assessing airway dynamics and resistance. This is the first study to compare the use of different interfaces: mouthpiece, mouth mask, and nasal mask, for oscillometry in an adult population. We report that using a mouth mask in oscillometry may provide a valid alternative to a mouthpiece in cohorts who may struggle to form the required tight seal that is typically required in oscillometry or spirometry.