Determining the etiology of an event arguably holds greater relevance to the patient’s diagnosis than simply tabulating numbers and measuring event duration. It might be suggested that the term “central” is somewhat vague, and that a more meaningful way to describe an event is whether or not it is associated with a closed airway. Examining respiratory tracings alone is insufficient for this pur...

This study was designed to evaluate the importance of sympathoadrenal activation in the acute cardiovascular response to apneas and the role of hypoxemia in this response. In addition, we evaluated the contribution of the vagus nerve to apnea responses after chemical sympathectomy. In six pigs preinstrumented with an electromagnetic flow probe and five nonpreinstrumented pigs, effects of period...

The within-breath modulation of muscle sympathetic nerve activity (MSNA) is well established, with greater activity occurring during expiration and less during inspiration. Whether ventilation per se affects the longer-term (i.e., minute-to-minute) regulation of MSNA has not been determined. We sought to define the specific role of ventilation in regulating sympathetic activation during chemore...

Schagatay, Erika, Johan P. A. Andersson, Magnus Hallén, and Birger Pålsson. Selected Contribution: Role of spleen emptying in prolonging apneas in humans. J Appl Physiol 90: 1623–1629, 2001.—This study addressed the interaction between short-term adaptation to apneas with face immersion and erythrocyte release from the spleen. Twenty healthy volunteers, including ten splenectomized subjects, pa...

BACKGROUND Obstructive apnea is a sleep disorder characterized by pauses in breathing during sleep: breathing is interrupted by a physical block to airflow despite effort. The purpose of this study was to test if osteopathy could influence the incidence of obstructive apnea during sleep in infants. METHODS Thirty-four healthy infants (age: 1.5-4.0 months) were recruited and randomized in two ...

The aim of this study was to investigate the effects of short repeated apneas on breathing pattern and circulatory response in trained (underwater hockey players: UHP) and untrained (controls: CTL) subjects. The subjects performed five apneas (A1-A5) while cycling with the face immersed in thermoneutral water. Respiratory parameters were recorded 1 minute before and after each apnea and venous ...

In this study we test the hypothesis that aortic nerve traffic is responsible for the pressor response to periodic apneas. In nine intubated, sedated chronically instrumented pigs, periodic obstructive apneas were caused by occlusion of the endotracheal tube for 30 s, followed by spontaneous breathing for 30 s. This was done under control (C) conditions, after section of the aortic nerve (ANS),...

Apnea of prematurity (AOP) is one of the most common diagnoses in preterm infants. Severe and recurrent apneas are associated with cerebral injury and adverse neurodevelopmental outcome. Despite pharmacotherapy and respiratory support to prevent apneas, a proportion of infants continue to have apneas and often need tactile stimulation, mask, and bag ventilation and/or extra oxygen. The duration...

BACKGROUND There is concern that opioid-based analgesia will worsen sleep-related respiratory insufficiency in patients with obstructive sleep apnea (OSA), resulting in serious morbidity or mortality. However, there are no studies that directly address the merit of this concern. Consequently, the authors designed this study as the first prospective, double-blind, placebo-controlled investigatio...

Obstructive sleep apnea is associated with sustained elevation of muscle sympathetic nerve activity (MSNA) and altered chemoreflex control of MSNA, both of which likely play an important role in the development of hypertension in these patients. Additionally, short-term exposure to intermittent hypoxic apneas can produce a sustained elevation of MSNA. Therefore, we tested the hypothesis that 20...