INTRODUCTION Bronchial challenge tests by inhalation of aerosolized methacholine (MCH) are commonly used in the clinical diagnosis of airway hyperresponsiveness (AHR). While the detection of airway narrowing relies on the patient's cooperation performing forced spirometry, body plethysmographic measurements of airway resistance are less depending on the patient's cooperation and do not alter th...

BACKGROUND Percutaneous dilational tracheostomy is normally a bronchoscope-guided procedure. The insertion of a bronchoscope into an endotracheal tube (ETT) affects resistance, flow, and alveolar pressure. To improve airway management and ventilation during percutaneous tracheostomy, we developed a double lumen endotracheal tube (DLET). The aim of this in vitro study was to compare the linear c...

childhood. Am J Respir Crit Care Med 2004; 169: 1209–1216. 4 Klug B, Bisgaard H. Measurement of lung function in awake 2–4-year-old asthmatic children during methacholine challenge and acute asthma: a comparison of the impulse oscillation technique, the interrupter technique, and transcutaneous measurement of oxygen versus whole-body plethysmography. Pediatr Pulmonol 1996; 21: 290–300. 5 Van No...

BACKGROUND Asthma is a chronic disease that is characterized by airway hyperresponsiveness and airway remodeling. The underlying mechanisms that mediate the pathological processes are not fully understood. Abl is a non-receptor protein tyrosine kinase that has a role in the regulation of smooth muscle contraction and smooth muscle cell proliferation in vitro. The role of Abl in airway hyperresp...

Background: The most important and complex phenomenon of respiratory function of the nose is related to different nasal anatomy. The differences in facial anatomic structure between different races may also be reflected in nasal resistance and airflow. Caucasians has different facial anatomic structure which is the reflection of intranasal resistance or consequence of airflow. The active anteri...

Introduction: One of the major concerns in laryngeal laser surgery is the risk of airway fire. The introduction ofwrapped tubes and metal tubes has reduced the fire hazards. However, these tubes are expensive and do not provide convenient access to the surgical field. There are few laboratory studies addressing the resistance of polyvinylchloride tubes against ignition in the given circum...

The upper airway (UA) of adult animals is known to contain carbon dioxide-sensitive receptors and UA CO2 reflexly affects breathing, UA dilator muscle activity and UA resistance. These effects may function in the control of UA patency. There is evidence that some UA reflexes are stronger in young than in adult animals, but it is not known whether CO2-sensitive receptors are present in the UA of...

It has been demonstrated that methacholine (MCh) challenge produces a greater increase in lung resistance in immature than in mature rabbits (R. S. Tepper, X. Shen, E. Bakan, and S. J. Gunst. J. Appl. Physiol. 79: 1190-1198, 1995). To determine whether this maturational difference in the response to MCh was primarily related to changes in airway resistance (Raw) or changes in tissue resistance,...