Assessment of nasal and sinus nitric oxide output using single-breath humming exhalations

Abstract

Nasal nitric oxide (NO) levels increase greatly during humming compared to silent exhalation. In this study, the physiological and anatomical factors that regulate NO release during humming have been characterised in 10 healthy subjects and in a model of the sinus and the nose.Single-breath humming caused a large initial peak in nasal NO output, followed by a progressive decline. The NO peak decreased in a step-wise manner during repeated consecutive humming manoeuvres but recovered completely after a silent period of 3 min. Topical nasal application of an NO synthase inhibitor reduced nasal NO by w50% but had no effect on the increase evoked by humming. Silently exhaled nasal NO measured immediately after repeated humming manoeuvres was between 5-50% lower than basal silent NO exhalation, suggesting variable continuous contribution from the sinuses to nasal NO. Among the factors known to influence normal sinus ventilation, ostium size was the most critical during humming, but humming frequency was also of importance.In conclusion, humming results in a large increase in nasal nitric oxide, which is caused by a rapid gas exchange in the paranasal sinuses. Combined nasal nitric oxide measurement with and without humming could be of use to estimate sinus ventilation and to better separate nasal mucosal nitric oxide output from sinus nitric oxide in health and disease. Eur Respir J 2003; 22: 323-329. This study was supported by a grant from the Swedish Heart-Lung Foundation, the Swedish Research Council and by a grant from University Federico II "Progetto scambi internazionali".Nitric oxide (NO) is released into the airway lumen [1], in particular in the upper airways [2][3][4]. The exact origin of NO found in nasal air and the relative contribution from different sources within the nasal airways are not known. The paranasal sinuses are major sources of NO in adult healthy subjects [5] and the concentrations in a healthy sinus may be very high, ranging 5-20 parts per million (ppm) [5]. The sinuses communicate with the nasal cavity through the ostia and the rate of gas exchange between these cavities is dependent on several factors, such as the size of the ostia, the volume of the sinus, the nasal airflow and intra-nasal pressure [6,7]. Proper ventilation is essential for maintenance of sinus integrity, and blockage of the ostium is a central event in the pathogenesis of sinusitis [8,9]. During normal ventilation, the time required to exchange all air in the sinuses is y30 min, with large inter-individual variation [7,10]. Sinus ventilation is much slower in patients with sinus disorders [10].Recently, the current authors have shown that nasal NO levels increase greatly during humming compared to normal silent nasal exhalation, probably by speeding up the sinus gas exchange, thereby increasing nasal NO output [11]. In a twocompartment model of the nose and sinus the authors demonstrated that pulsating airflow, created by humming, causes a dramatic increase in gas exchange between these cavities [11].In the ...

Nasal Breathing Exercise and its Effect on Symptoms of Allergic Rhinitis

“…Though the study does not directly analyse the mechanism of NBE and its effects on AR, the author proposes a plausible explanation for the improvement in symptoms after NBE with the available literature on the subject. Various studies on nasal nitric oxide (nNO) in humans have revealed nitric oxide to be maximally produced from the nasal and paranasal sinus [11][12][13]. There have been also interesting analysis of humming and increased nNO as compared with normal quiet nasal exhalation suggesting improved paranasal sinus ventilation with this maneuver [14,15].…”

Nitric oxide in primary ciliary dyskinesia

“…The oscillation generated by the humming is thought to increase gas exchange across the osteomeatal complex [90,92]. During tidal breathing, it can take up to 30 min to completely clear sinus gases into the nasal cavity, but with humming, this occurs in one exhalation [93,94]. In healthy volunteers, humming leads to a 15-fold peak in nasal nitric oxide, compared with quiet exhalation [90].…”

Bronchoalveolar lavage, sputum and exhaled clinically relevant inflammatory markers: values in healthy adults

“…They include sex and sexual hormones, body weight and age, circadian changes of respiratory function in health and disease, caffeine and alcohol, meals rich in nitrate, genetic background for some enzymes, upper respiratory tract infection, exercise, drugs (including inhibitors of NO synthases) and of course smoking [46,[54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73]. Moreover, FeNO levels in healthy subjects are influenced by atopy, i.e.…”