We observed the response of vascular resistance and venous oxygen (O2) saturation to sinusoidally modulated continuous exercise of the isolated dog calf. Stimulus frequency was varied sinusoidally between 0.5 Hz and 1 Hz with modulation frequencies ranging from 0.005 Hz to 0.05 Hz. Venous O2 responses were corrected for dispersion due to vascular and catheter transit. As modulation frequency wa...

OBJECTIVE Wet cupping is a traditional bloodletting method recommended for controlling of respiratory disease complications. This study aimed to compare the efficacy of wet cupping vs. venesection on arterial O2 saturation level of smokers. METHODS This is a randomized controlled clinical trial which started with simple sampling of smokers. After administering spirometery, participants (N = 1...

BACKGROUND AND PURPOSE Sleep-disordered breathing (SDB) represents a risk factor for cardiovascular morbidity after a cerebral ischemic event (acute ischemic event, ischemic stroke, or transient ischemic attack). In the present study, endothelial function and arterial stiffness were analyzed in patients who experienced a postacute ischemic event with relation to SDB, sleep disruption, and noctu...

Background To clarify the efficiency of mask O2 and high-flow O2 (HFO) treatments following cardiopulmonary bypass (CPB) in obese patients. Methods During follow-up, oxygenization parameters including arterial pressure of oxygen (PaO2), peripheral oxygen saturation (SpO2), and arterial partial pressure of carbon dioxide (PaCO2) and physical examination parameters including respiratory rate, h...

a significant reduction in arterial blood oxygen saturation during fiberoptic bronchoscopy has been proved but it is not yet known whether all patients need supplemental oxygen during this procedure. the aim of study is to examine the relationship between peak expiratory flow rate (pefr) before bronchoscopy and oxygen desaturation during bronchoscopy. measurement of pefr (% predicted) performed...

The aim of the present study was to evaluate the accuracy, in comparison with a reference method, of the Nellcor N-20P pulse oximeter in the assessment of oxyhaemoglobin saturation (Sa,O2). Sa,O2 was monitored at rest by the Nellcor N-20P pulse oximeter in 100 subjects (82 males, mean age 68+/-12 yrs) consecutively enroled. At the same time, an arterial blood sample was collected for the measur...

It is known that Cys beta 93 in hemoglobin A reacts with sulfhydryl reagents more rapidly in the oxy than in the deoxy form. In this study, the reaction of the residues toward 4,4'-dithiodipyridine was measured at various degrees of saturation with O2. Analysis of initial rates of the reaction revealed that an intermediate, which reacts even more rapidly than the oxy form, occurs in the course ...

To investigate the contribution of the peripheral chemoreceptors to the susceptibility to posthyperventilation apnea, we evaluated the time course and magnitude of hypocapnia required to produce apnea at different levels of peripheral chemoreceptor activation produced by exposure to three levels of inspired P(O2). We measured the apneic threshold and the apnea latency in nine normal sleeping su...

Considerable interindividual differences in the Q˙-V˙O2 relationship during exercise have been documented but implications for submaximal exercise tolerance have not been considered. We tested the hypothesis that these interindividual differences were associated with differences in exercising muscle deoxygenation and ratings of perceived exertion (RPE) across a range of submaximal exercise inte...

INTRODUCTION Physiological and emotional stressors increase symptoms of concussion in recently injured individuals and both forms of stress-induced symptoms in people recovering from mild traumatic brain injury (mTBI), but who are asymptomatic when not stressed or are at rest. METHODS Healthy asymptomatic adults (25.0 ± 5.1 years) with a history of mTBI (n = 36) and matched healthy controls (...