LAUSR

Objectives: Subjective assessment of nasal obstruction with patient-reported outcome measures such as visual analogue scale and NOSE score may be limited in chronic mouth breathing subjects who are not consciously aware of nasal breathing difficulties. This study investigates a simple objective screening tool to assess the capacity for comfortable nasal breathing that is based on sealing the lips and mouth with tape and assessing whether the subject can breathe comfortably through the nose for up to three minutes. Method: Cross-sectional, multi-center cohort study with 663 participants (ages: 3-83 years, 50.5% female). Lips were gently sealed using MicroPore paper tape; timer was used to assess how long the participants were able to breathe comfortably through the nose for up to 180 seconds. Other measures included subjective rating of perceived difficulty with nasal breathing (VAS, 0-100) as well as self-assessed reports of mouth breathing. Results: There were 9.3% of patients with subjective reports of moderate to severe nasal obstruction (VAS> 50) and 17.2% of patients with predominance of self-reported mouth breathing in this series. Overall, 93.4% of participants successfully passed the nasal breathing test. Among patients with habitual mouth breathing, 83.5% (91/109) were able to breathe comfortably through the nose when instructed to do so for the entire 3-minute duration tested. Similarly, there were 67% (40/59) patients with VAS score >50 who could breathe comfortably through the nose for >180 seconds despite subjective reports of moderate to severe nasal obstruction. Participants unable to breathe exclusively through the nose for 180 seconds had increased likelihood of mouth breathing while awake (OR 4.12, 95% confidence interval 2.14-7.89, p<.0001) as well as increased odds of mouth breathing while asleep (OR 3.05, 95% confidence interval 1.61-5.72, p=0.0003). Conclusion: Objectively testing whether a subject can breathe through the nose with the lips and mouth taped for three minutes can identify patients at risk of mouth breathing and is a simple and effecting screening tool to distinguish organic nasal obstruction from functional mouth breathing habit and or nasal resistance.