The regulation of respiration during sleep and anesthesia

During the 1976 Fall Meeting of the American Physiological Society Dr. Lahiri and I learned that no plans were being formulated for holding a symposium on Respiratory Control during the 1977, International Congress. Not to hold such a symposium, we felt, would be the loss of a unique opportunity for us "regulationists" to exchange ideas viva voce with our international colleagues. It would also break a tradition most recently enjoyed at Srinagar, India in 1974 and at Warsaw, Poland in 1971. After a time-consuming false start we had the good fortune to get advice from Dr. Pierre Dejours to make our plans known to Dr. Henry Gautier. This we did. There resulted an excellent three days of discussion and hospitality at the Faculte de Medecine Saint-Antoine in Paris immediately preceding the International Congress. The aim of the co-chairmen was to gather an international mixture of both the younger and more senior experts to discuss, argue, and maybe even agree on a point or two arising from their current investigations. We wanted to feature, however, recent research trying to determine the influence of sleep and anesthesia on the regulation of respiration. That the sessions were lively and presumably profitable was never more in evidence than when on the second day at 6:15 p.m. after fully nine hours of discussion, argumentation, and some agreement I counted 78 participants still participating. The symposium's proceedings which follow are divided into four sections. The first section treats the influence of Sleep and Anesthesia on the regulation of respiration. Fifteen papers examine this influence on many systems--muscles of respiration, central neural components, mechanical responses of the organism to the classical stimuli of hypercapnia and hypoxia. The second section treats the influence of Brain Acid-Base Environment on respiratory regulation. Here seven papers discuss the response of brain fluid composition to changes in the acid-base composition of the plasma compartment under such conditions as the hypocapnic hypoxia of altitude acclimatization, transient hypercapnia, and metabolic derangement. Respiration both determines and is determined by this fluid. The third section treats the influence of Peripheral Input on the regulation of respiration. These thirteen papers investigate influences on the shape and size of the stimulus to the peripheral chemoreceptors, various aspects of the chemoreceptors' dynamic response, the role of time of central arrival of such activity on ventilation. New information on airway receptors is presented as well. The fourth and final section treats the influence of Central Interaction on the regulation of respiration. Six papers focus on respiratory phase switching and the interplay between peripheral and central chemoreceptor input.