The pathogenesis of cystic fibrosis (CF) airways infection is unknown. Two hypotheses, "hypotonic [low salt]/defensin" and "isotonic volume transport/mucus clearance," attempt to link defects in cystic fibrosis transmembrane conductance regulator-mediated ion transport to CF airways disease. We tested these hypotheses with planar and cylindrical culture models and found no evidence that the liq...

Ischemic tracheal complications due to the ETT cuff occur in approximately 10 percent of mechanically ventilated critically ill patients despite the use of high-volume, low-pressure ETT cuffs. Using a laboratory model, we studied the effects of airway pressure on three different ETT cuff designs, including two "low pressure" designs. Positive airway pressure acted on the "low pressure" cuffs to...

asthma and chronic obstructive pulmonary disease (copd) are highly prevalent chronic diseases in the general population. both are characterized by similar mechanisms: airway inflammation, airway obstruction, and airway hyperresponsiveness. however, the distinction between the two obstructive diseases is not always clear. multiple epidemiological studies demonstrate that in elderly people with o...

The mechanism by which deep inspirations protect against increased airway responsiveness in nonasthmatic subjects is not known. The aim was to investigate the role of airway closure and airway narrowing in deep inspiration bronchoprotection. Twelve nonasthmatic and nine asthmatic subjects avoided deep inspirations (DI) for 20 min, then took five DI expired to functional residual capaciy (DI-FRC...

The aim of this study was to evaluate the oropharyngeal (OP) and nasal passage (NP) volumes along with various airway variables of patients with normal nasorespiratory functions having different dentofacial skeletal patterns and to evaluate the correlations between different variables and the airway. One hundred and one patients (57 males and 44 females, aged 14-18 years) having pre-treatment c...

How normal airway dimensions change with lung volume is of great importance in determining flow limitation during the normal forced vital capacity maneuver as well as in the manifestation of obstructive lung disease. The literature presents a confusing picture, with some results suggesting that airway diameter increases linearly with the cube root of lung volume and others showing a highly nonl...

Airway relaxation in response to isoprenaline, sodium nitroprusside (SNP) and electrical field stimulation (EFS) was compared under static and dynamic conditions. The capacity of relaxants to reduce airway stiffness and, thus, potentially contribute to bronchodilation was also investigated. Relaxation responses were recorded in fluid filled bronchial segments from pigs under static conditions a...

INTRODUCTION The aim of the study was to determine the most accurate threshold value for airway volume quantification based on specific experimental conditions. METHODS Ten scans from the airway prototype were obtained by using cone-beam computed tomography. The volume from each scan was measured with 8 values (25, 50, 70, 71, 72, 73, 74, and 75) of the threshold tool from the Dolphin softwar...

The mechanisms underlying not well-controlled (NWC) asthma remain poorly understood, but accumulating evidence points to peripheral airway dysfunction as a key contributor. The present study tests whether our recently described respiratory system reactance (Xrs) assessment of peripheral airway dysfunction reveals insight into poor asthma control. The aim of this study was to investigate the con...