Double-chamber plethysmography is a well established noninvasive method of assessing airflow obstruction in small lab animals. It allows measurement of the specific airway resistance (sRaw), which unlike enhanced pause (Penh), is a meaningful airway mechanics parameter. Since sRaw is measured in spontaneously breathing mice, a limitation of the method is the inability to exclude nasal resistanc...

Mouth breathing may cause changes in muscle activity, because an upper airway obstruction leads may cause a person to extend his/her head forward, demanding a higher inspiratory effort on the accessory muscles (sternocleidomastoids). This purpose of this study is to compare, using electromyography (EMG), the activity pattern the sternocleidomastoid and upper trapezius muscles in mouth breathing...

The interaction between oral-facial structural growth and muscle activity starts early in development and continues through childhood. Chronic oral breathing is an important clinical marker of orofacial muscle dysfunction, which may be associated with palatal growth restriction, nasal obstruction, and/ or a primary disorder of muscular or connective tissue dysfunction. It is easily documented o...

An association between mouth breathing during sleep and increased propensity for upper airway collapse is well documented, but the effect of treatment for nasal obstruction on mouth breathing during sleep and simultaneous obstructive sleep apnoea (OSA) severity has not been described previously. A randomised single blind placebo- and sham-controlled crossover study of treatment (topical deconge...

We examined the effect of oral breathing on respiratory movements, including the number of respirations and the movement of the thoracic wall at rest and while chewing gum. Forty normal nose breathers were selected by detecting expiratory airflow from the mouth using a CO2 sensor. Chest measurements were recorded using a Piezo respiratory belt transducer, and electromyographic (EMG) activity of...

introduction: a reduction or cessation of the ability to breathe through the nose can affect a person's overall health. nasal passage blockage can also result in snoring. difficulty in breathing through the nose after rhinoplasty is a serious problem and patient dissatisfaction can be significant even when cosmetic results are excellent. long-term impacts on the quality of life and contrib...

1. Sympathetic activation in congestive heart failure indicates a poor prognosis. Haemodynamic correlates of increased sympathetic nerve traffic to muscle (MSNA) and to the heart have been well characterized, but these account for only 50 to 60% of the variance in sympathetic activity between patients.2. In healthy subjects, breathing pattern modulates MSNA and positive airway pressure consiste...

Correlations between breathing mode and craniofacial morphology were investigated in 47 children at the ages of 6-15 years (average, 9.9 years). Apart from history and clinical examination, nasal endoscopy, rhinomanometry and measurements of cephalometric radiographs were included in the analysis. After separating the patients into a "normal face" group and a "long face" group by measuring the ...

OBJECTIVE High-flow humidified nasal cannula is often used to provide noninvasive respiratory support in children. The effect of high-flow humidified nasal cannula on effort of breathing in children has not been objectively studied, and the mechanism by which respiratory support is provided remains unclear. This study uses an objective measure of effort of breathing (Pressure. Rate Product) to ...

We investigated the airway responses evoked by nasal wood smoke in anesthetized Sprague-Dawley rats. Wood smoke (5 ml, 1.4 ml/s) was delivered into an isolated nasal cavity while animals breathed spontaneously. In study 1, nasal wood smoke triggered either an apneic response (n = 26) or a sniff-like response (n = 16) within 1 s after smoke exposure in 42 normal rats. Both airway responses were ...