Study of nasal cycles in children by acoustic rhinometry

Real-time observation of nasal cycle during sleep with polysomnography

PURPOSE

To investigate the nasal cycle (NC) during sleep in healthy individuals without nasal obstruction or obstructive sleep apnoea via a flexible wearable respiratory monitoring system in a continuous and real-time manner.

METHODS

NC during sleep was continuously measured in 30 healthy individuals (15 women, 15 men) via long-term sleep respiratory monitoring system, while sleep stage and body position were simultaneously recorded via polysomnography (PSG). The number of NC transitions and positional changes were documented each night. Additionally, time intervals between NC transitions and their closest positional changes during sleep were meticulously recorded to investigate potential correlations between them.

RESULTS

A total of 86.7% of the participants displayed the classic NC, with a mean duration of 6.43 ± 2.33 h. Nightly observations revealed an average occurrence of 2.19 ± 0.40 NC transitions, predominantly occurring during REM stage (68.4%), and 9.15 ± 7.77 postural changes. Analysis of the intervals between NC transitions and positional changes revealed an average absolute value of 27.72 ± 10.85 min, with a substantial 56.4% exceeding 30 min, indicating a non-obvious sequence order among them.

CONCLUSION

NC can be measured in a continuous and real-time manner, the transitions occur mainly during the REM stage. However, we have not identified a clear correlation between NC transition and positional change.

Integrating the Divided Nasal Cannula Into Routine Polysomnography to Assess Nasal Cycle: Feasibility and Effect on Outcomes

STUDY OBJECTIVES

Patients suspected to have sleep-disordered breathing underwent an overnight polysomnography using a divided nasal cannula to gain additional information about the nasal cycle during sleep.

METHODS

This was a prospective, observational cohort study replacing the undivided nasal cannula with a divided nasal cannula during routine polysomnography (n = 28).

RESULTS

Integration of the divided nasal cannula pressure transducer system into routine polysomnography was easy and affordable. Most patients (89%) demonstrated nasal cycle changes during the test. Nasal cycle changes tended to occur during body position changes (62%) and transitions from non-rapid eye movement sleep to rapid eye movement sleep (41%). The mean nasal cycle duration was 2.5 ± 2.1 hours. Other sleep study metrics did not reveal statistically significant findings in relation to the nasal cycle.

CONCLUSIONS

Replacing an undivided nasal cannula with a divided nasal cannula is easy to implement, adding another physiologic measure to polysomnography. Although the divided nasal cannula did not significantly affect traditional polysomnographic metrics such as the apnea-hypopnea index or periodic limb movement index based on this small pilot study, we were able to replicate past nasal cycle findings that may be of interest to sleep clinicians and researchers. Given the ease with which the divided nasal cannula can be integrated, we encourage other sleep researchers to investigate the utility of using a divided nasal cannula during polysomnography.

Mudança nas áreas nasais em crianças com respiração oral após a limpeza e massagem nasal

RESUMO A avaliação e quantificação das possíveis alterações da cavidade nasal são necessárias para o auxílio diagnóstico e tratamento de crianças que respiram predominantemente pela boca. O modo respiratório oral pode desencadear distúrbios da fala, deformidades da face, mau posicionamento dos dentes, postura corporal inadequada e alterações no sistema respiratório. Objetivo analisar as mudanças ocorridas na geometria das cavidades nasais, antes e depois da limpeza nasal por meio da aeração nasal e da rinometria acústica em crianças com respiração oral. Método Foram selecionadas 20 crianças com idade entre quatro e 12 anos. A coleta foi realizada no Laboratório Multifuncional do Departamento de Fonoaudiologia da Universidade Federal de Pernambuco. Foi aplicado o Índice de Identificação dos Sinais e Sintomas da Respiração Oral; marcação da aeração nasal por meio do espelho milimetrado de Altmann e o exame da geometria nasal por Rinometria Acústica. Depois da limpeza e massagem nasal com o soro fisiológico, foram realizados os mesmos procedimentos. Resultados Observaram-se mudanças significantes nas áreas relativas ao fluxo aéreo nasal em ambos os lados, após limpeza e massagem nasais. Quanto à geometria nasal, aferida por meio da rinometria acústica, o efeito da limpeza e massagem nasal mostrou-se discreto, quando feita a comparação entre as narinas. Conclusão As medidas de aeração nasal mostraram sensibilidade à técnica de limpeza e massagem e as medidas da geometria nasal confirmaram seu efeito sobre a fisiologia respiratória.

Measuring and Characterizing the Human Nasal Cycle

Nasal airflow is greater in one nostril than in the other because of transient asymmetric nasal passage obstruction by erectile tissue. The extent of obstruction alternates across nostrils with periodicity referred to as the nasal cycle. The nasal cycle is related to autonomic arousal and is indicative of asymmetry in brain function. Moreover, alterations in nasal cycle periodicity have been linked to various diseases. There is therefore need for a tool allowing continuous accurate measurement and recording of airflow in each nostril separately. Here we provide detailed instructions for constructing such a tool at minimal cost and effort. We demonstrate application of the tool in 33 right-handed healthy subjects, and derive several statistical measures for nasal cycle characterization. Using these measures applied to 24-hour recordings we observed that: 1: subjects spent slightly longer in left over right nostril dominance (left = 2.63 ± 0.89 hours, right = 2.17 ± 0.89 hours, t(32) = 2.07, p < 0.05), 2: cycle duration was shorter in wake than in sleep (wake = 2.02 ± 1.7 hours, sleep = 4.5 ± 1.7 hours, (t(30) = 5.73, p < 0.0001). 3: slower breathing was associated with a more powerful cycle (the extent of difference across nostrils) (r = 0.4, p < 0.0001), and 4: the cycle was influenced by body posture such that lying on one side was associated with greater flow in the contralateral nostril (p < 0.002). Finally, we provide evidence for an airflow cycle in each nostril alone. These results provide characterization of an easily obtained measure that may have diagnostic implications for neurological disease and cognitive state.

Effects of radiofrequency thermal ablation on the nasal cycle measured using rhinomanometry

OBJECTIVE

This study was designed to research the effects of radiofrequency thermal ablation (RFTA) surgery on the nasal cycle, with anterior rhinomanometry being used for assessment.

METHODS

Thirty patients with inferior concha hypertrophy and 13 healthy volunteers were included in this study. An anterior rhinomanometry was performed on each of the patients before surgery and at 1 month and 6 months after surgery, and on the volunteers in the control group, simultaneously.

RESULTS

Nineteen of the 30 patients and 8 of the 13 healthy participants showed a distinct type of nasal cycle at different periods of measurement. The mean of the total nasal airflow of the patients was lower before RFTA surgery but increased at a rate of 71.07%, closer to the value of the control group, after RFTA surgery. After RFTA, the unilateral nasal airflow (fmin and fmax) values increased at ratios of 22.36% and 94.44%, respectively. The amplitude (fmax-fmin) showed a statistically significant decrease in the postoperative period (108.43 ± 54.37), when compared with that of the preoperative period (202.80 ± 81.24) (P < .01).

CONCLUSION

We conclude that the RFTA is a useful method for treating inferior concha hypertrophy, because it positively affects the nasal physiology, increasing the total nasal airflow without changing the nasal cycle time.

Nasal inflammatory mediators and specific IgE production after nasal challenge with grass pollen in local allergic rhinitis

BACKGROUND

Evidence exists of a new form of local allergic rhinitis (LAR) with local production of specific IgE (sIgE) and a positive response to nasal allergen provocation test (NAPT) in patients previously diagnosed with idiopathic rhinitis. However, the immunologic mechanisms involved are still poorly understood.

OBJECTIVE

We explored the involvement of nasal sIgE, eosinophil, and mast cell activation in the response to NAPT with grass pollen (NAPT-grass) in a group of patients already classified with LAR.

METHODS

Out-of-spring NAPT-grass was performed in 30 patients with LAR and 30 healthy controls. Nasal symptoms, acoustic rhinometry, and nasal lavage were performed at baseline and 15 minutes and 1, 6, and 24 hours post-NAPT. Tryptase, eosinophilic cationic protein (ECP), and total and sIgE to grass pollen were measured in nasal lavage by immunoassays.

RESULTS

NAPT-grass was positive in all patients with LAR. We detected significant increases of tryptase and ECP in 40% and 43%, respectively, at 15 minutes and 1, 6, and 24 hours post-NAPT compared with baseline (P < .05). sIgE was increased in 30%, with significant increases at 1 and 6 hours (P < .05) and 24 hours (P = .002) post-NAPT. The maximum release of tryptase was detected 15 minutes after NAPT, whereas the maximum release of ECP and sIgE was detected 24 hours after challenge. NAPT-grass was negative in all healthy controls, with no increase in tryptase, ECP, total IgE, or sIgE.

CONCLUSION

These results demonstrate that patients with LAR had local production of sIgE and mast cell/eosinophil activation induced by nasal exposure to grass pollen.