The effects of full lung inflation on respiratory conductance (Grs) and reactance (Xrs) were measured in 15 subjects with moderate to severe chronic obstructive pulmonary disease (COPD) and 11 matched healthy control subjects. Airway distensibility was estimated from the ratio of the difference of Grs between functional residual capacity and total lung capacity to the relevant changes in lung v...

Surgery patients in Japan undergo routine spirometry testing prior to general anesthesia. The use of a flow sensor during general anesthesia has recently become common. However, it is not certain whether the information derived from flow-volume curves is being adequately used for mechanical ventilation management during general anesthesia. So far, there have been no attempts to calculate airway...

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...

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...

A method for quantitative measurement of gas volume changes in upper airway is presented in this paper. The aim of this study is to assess the feasibility of a novel Cone Beam Computerized Tomography (CBCT) technique for quantitative measurement of gas volume in upper airway. Our application is defining and tracking minute volume changes (a few milliliters) of airways caused by surgery, such as...

BACKGROUND Oral breathing and maxillary deficiency are often associated with steep mandibular plane angle, and retrognathic mandible compared with the faces of healthy controls. Some studies suggested that after rapid maxillary expansion, improvement in nasal breathing and repositioning of mandible with transitory increasing of facial height and, in some cases, spontaneous forward repositioning...

BACKGROUND The purpose of this retrospective study was to develop a two- and three-dimensional analysis of the airway using cone-beam computed tomography (CBCT) and to determine whether the airway space would be changed in mandibular prognathism after bimaxillary surgery involving maxillary posterior impaction. METHODS Patients requiring orthognathic surgery from 2012 to 2014 were recruited f...

Background : As the basic biological relationship of form and function, changes in the normal pattern of nasopharyngeal space can profoundly affect the development of the craniofacial growth. The lateral cephalogram, part of the patient's normal records for orthodontic treatment, may show some of these changes either at the initial examination or later during treatment. The validity of the info...

BACKGROUND Human patient simulators and airway training manikins are widely used to train airway management skills to medical professionals. Furthermore, these patient simulators are employed as standardized "patients" to evaluate airway devices. However, little is known about how realistic these patient simulators and airway-training manikins really are. This trial aimed to evaluate the upper ...