Perception of dyspnea during histamine- and methacholine-induced bronchoconstriction.

Background: Perception of dyspnea is poorly related to bronchoconstriction and may be influenced by distinct psychophysiologic stimuli.

Objective: This study compared the perceived psychophysiologic changes during histamine- and methacholine-induced bronchoconstriction using verbal as well as nonverbal assessment techniques.

Methods: Perception of dyspnea was studied during induced bronchoconstriction in 40 atopic subjects randomly ascribed to either histamine (n = 20) or methacholine (n = 20) bronchial challenge.

Memory deficits at 0.6 MPa ambient air pressure.

We investigated the effects of an elevated ambient air pressure of 0.6 MPa on verbal memory performance. Twenty-four experienced divers were compressed in a dry hyperbaric chamber to pressures equivalent to 0.

Atopy, airway reactivity and compressed air diving in males.

A decline in expiratory flow rates in divers has recently been attributed to chronic exposure to hyberbaric air. Airway hyperresponsiveness (AHR) to stimuli due to a hyperbaric environment may play a certain role in this context. The aim of this study was to determine the prevalence of AHR in compressed air divers and to assess the value of bronchial challenges for prediction of fitness to dive.