This study aimed to assess the effects of bone-borne and tooth-borne surgically assisted rapid maxillary expansion on the volumes of the nose and nasal airway 2 yr after maxillary expansion. This prospective cohort study included 32 patients with transverse maxillary hypoplasia. Expansion was performed with a tooth-borne distractor (Hyrax) in 19 patients and with a bone-borne distractor [transp...

JAMA 1981; 245:2414-18 6 Rotman HH, Liss HP, Weg JG. Diagnosis of upper airway obstruction by pulmonary function testing. Chest 1975; 68:79699 7 Shore ET, Millman RE Abnormalities in the flow-volume loop in obstructive sleep apnea sitting and supine. Thorax 1984; 39: 775-79 8 Chaudhary BA, Elguindi AS, Giacomini K, Speir WA. Diagnosis of sleep apnea by flow-volume loops [abstract]. Am Rev Respi...

Lung volume dependence of pharyngeal airway patency suggests involvement of lung volume in pathogenesis of obstructive sleep apnea. We examined the structural interaction between passive pharyngeal airway and lung volume independent of neuromuscular factors. Static mechanical properties of the passive pharynx were compared before and during lung inflation in eight anesthetized and paralyzed pat...

BACKGROUND Obstructive sleep apnoea (OSA) is commonly associated with obesity and can be improved by weight loss. Changes in upper airway size related to regional fat loss may mediate the improvement in OSA. This study aimed to assess changes in upper airway size and regional facial and abdominal fat with weight loss and their association with OSA improvement. METHODS Middle-aged obese men wi...

Tidal airway closure occurs when the closing volume exceeds the end-expiratory lung volume, and it is commonly observed in general anaesthesia, particularly in obese patients. Animal studies suggest that tidal airway closure causes injury to peripheral airways, characterized histologically by rupture of alveolar-airway attachments, denuded epithelium, disruption of airway smooth muscle and incr...

1. Airway resistance was measured close to functional residual capacity before and after a full inhalation of total lung capacity, as well as before and after a full exhalation to residual volume. 2. The effects of these volume manoeuvres upon airway resistance (and associated lung volume) were determined in four resting normal male subjects and in six normal men during experimentally induced b...

BACKGROUND Active sodium absorption is the dominant mechanism of ion transport in airway epithelium, but its role in pulmonary physiology and airway host defense is unknown. To address this question, we studied the function of airway epithelial cells and determined the frequency of pulmonary symptoms in patients with systemic pseudohypoaldosteronism, a salt-losing disorder caused by loss-of-fun...

5-HT2 receptor activity in the hypoglossal nucleus and hypercapnia is associated with airway dilation. 5-HT neurons in the medullary raphe and hypercapnia are responsible for tidal volume change. In this study, the effects of 5-HT2 receptors in the dorsomedial medulla oblongata (DMM), which receives projections from the medullary raphe, and hypercapnia on airway resistance and respiratory varia...

Independent of airway pressure, pulmonary resistance is known to fall with increasing tidal volumes, traditionally thought to result from radial traction on the airways. R. C. Anafi and T. A. Wilson (J Appl Physiol 91: 1185-1192, 2001) recently presented a model of a single terminal airway that explains the tidal volume-associated fall in resistance with an additional mechanism pertinent to nar...

Vascular congestion could play an important role in causing airway narrowing in asthma. However, the effects of altered bronchial vascular volume and blood flow on airway morphology and pulmonary resistance have not been studied. The aim of this study was to measure airway calibre and vascular volume during inhalation of reputed dilators and constrictors of the airway vasculature in sheep. Afte...