We refer to the recent study by OOSTVEEN et al. [1] on bronchodilator response in 4-yr-old children with different wheezing phenotypes. The forced oscillation technique is particularly suited to 2–7-yr-old children, and its suitability to assess bronchodilator responsiveness is still being investigated. Thus, the study is of great clinical relevance and, though of a narrow age range, is a welco...

The human pharyngeal airway during sleep is conventionally modeled as a Starling resistor. However, inspiratory flow often decreases with increasing effort (negative effort dependence, NED) rather than remaining fixed as predicted by the Starling resistor model. In this study, we tested a major prediction of the Starling resistor model--that the resistance of the airway upstream from the site o...

The temporal origins of childhood asthma are incompletely understood. We hypothesize that allergen sensitization which begins in early infancy causes IgE-mediated airway and vascular remodeling, and airway hyper-responsiveness. Mice were sensitized with ovalbumin (OVA) without or with anti-IgE antibody from postnatal day (P) 10 through P42. We studied airway resistance in response to Methacholi...

Using the forced oscillation technique, we tracked airway resistance continuously during quiet breathing (QB) and deep inspiration (DI), thus observing fluctuations in resistance that may reflect mechanisms of airway stretch and renarrowing. After DI, however, the resistance may be depressed for a period not related to volume changes. We hypothesized that this gradual increase in resistance aft...

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification of chronic obstructive pulmonary disease (COPD) does not always match with other clinical disease descriptors such as exacerbation frequency and quality of life, indicating that forced expiratory volume in 1 s (FEV(1)) is not a perfect descriptor of the disease. The aim of this study was to find out whether changes...

Superior vena cava syndrome (SVCS) patients sometimes show signs of obstructive sleep apnea (OSA). However, the mechanism causing hypoxia during sleep in SVCS patients is still uncertain. The aim of this study was to elucidate 1) the changes in central and peripheral respiratory resistance with SVCS; and 2) interpret the mechanism underlying the development of hypoxia during sleep in patients w...

We studied eight heavy snorers with upper airway resistance syndrome to investigate potential effects of sleep on expiratory airway and lung resistance, intrinsic positive end-expiratory pressure, hyperinflation, and elastic inspiratory work of breathing (WOB). Wakefulness and non-rapid-eye-movement sleep with high- and with low-resistance inspiratory effort (H-RIE and L-RIE, respectively) were...

The isolated upper airway pressure and flow changes during electrical stimulation of the genioglossus muscle in spontaneously breathing anesthetized dogs were measured at given pressures in the inspiratory direction. Upper airway resistance was maximal during no stimulation and decreased rapidly with stimulation at frequencies up to about 40 Hz.