Obstructive sleep apnea causes intermittent hypoxia (IH) during sleep and is associated with dysregulation of glucose metabolism. We developed a novel model of clinically realistic IH in mice to test the hypothesis that IH causes hyperglycemia, glucose intolerance, and insulin resistance via activation of the sympathetic nervous system. Mice were exposed to acute hypoxia of graded severity (21,...

Near-infrared spectroscopy (NIRS) is increasingly used as a non-invasive technique for monitoring cerebral oxygenation and haemodynamics . Simple continuous-wave (CW) NIRS systems utilising differential spectroscopy can measure quantitative changes in oxyand deoxyhaemoglobin (∆[O2Hb], ∆[HHb]) but only from an arbitrary baseline. Numerous studies of changes in cerebral oxygenation and haemodynam...

PURPOSE The aim of this study was to investigate the impact of exercise-induced hypoxaemia (EIH) developed at sea-level on exercise responses at moderate acute altitude. METHODS Twenty three subjects divided in three groups of individuals: highly trained with EIH (n = 7); highly trained without EIH (n = 8) and untrained participants (n = 8) performed two maximal incremental tests at sea-level...

58 patients who underwent on-pump coronary artery bypass graft surgery were evaluated for changes in regional cerebral oxygen saturation (rSO2) measured by near infrared spectroscopy (NIRS). If rSO2 during the operation fell to more than 20% under the baseline, standardized interventions were undertaken to maintain rSO2. Despite those interventions, in some cases we observed inability to mainta...

Obstructive sleep apnoea (OSA) is associated with oxygen desaturation to a varying degree. A patent foramen ovale (PFO) may allow interatrial right-to-left shunting. The hypothesis of the current study was that oxygen desaturation will occur more often, in proportion to the frequency of respiratory disturbances, in OSA subjects with PFO than in those without. In a group of 209 subjects diagnose...

OBJECTIVE The number of desaturations determined in recordings of pulse oximeter saturation (SpO2) primarily depends on the time over which values are averaged. As the averaging time in pulse oximeters is not standardized, it varies considerably between centers. To make SpO2 data comparable, it is thus desirable to have a formula that allows conversion between desaturation rates obtained using ...

STUDY OBJECTIVES Some respiratory patients exhibit oxygen desaturation during rehabilitative walking but not during maximal cardiopulmonary exercise testing (CPET). We evaluated exercise-induced desaturation during 6-min walk testing (6MWT) in comparison with CPET in patients with COPD and determined the reproducibility of the phenomenon. PATIENTS We tested 80 consecutive patients with COPD (...

Introduction: Standard monitoring of severe traumatic brain injury patients (TBI) by intracranial pressure (ICP) and cerebral perfusion pressure (CPP) monitoring fails to recognize episodes of cerebral oxygen desaturation. We found and characterized frequent episodes of desaturation of jugular venous oxygen (SjO2) in the face of normal ICP and CPP. Methods: Fifty six patients with severe TBI ha...

OBJECTIVE Altitude can affect the diagnostic accuracy of portable monitors used to diagnose suspected obstructive sleep apnea syndrome on the basis of oxygen desaturation measurements. The aim of this study was to determine agreement between the desaturation index measured by oximetry and the apnea-hypopnea index measured by polysomnography in Mexico City (2240 m above sea level). We also wishe...

BACKGROUND: The link between obstructive sleep apnea and difficult intubation needs to be fully investigated made clear. If a compromised airway can anticipated managed; it lessen the likelihood of adverse consequences. AIM: aim this study was investigate incidence, severity, possible association in individuals with unexpected endotracheal their associated clinical polysomnographic findings. ME...