Background: Serial blood draws for the assessment of a trauma patient’s hemoglobin (sHgb) and hematocrit (sHct) is standard practice. In the event of multiple casualties this process can be time consuming and lead to the inefficient use of valuable resources. A device that would allow for continuous real-time, non-invasive monitoring of hemoglobin and tissue perfusion would not only improve the...

Within individuals, critical power appears sensitive to manipulations in O2 delivery. We asked whether interindividual differences in forearm O2 delivery might account for a majority of the interindividual differences in forearm critical force impulse (critical impulse), the force analog of critical power. Ten healthy men (24.6 ± 7.10 years) completed a maximal effort rhythmic handgrip exercise...

2 Acclimatization to hypoxia requires time to complete the adaptation mechanisms that influence 3 oxygen (O2) transport and O2 utilization. Although decreasing hemoglobin (Hb) O2 affinity 4 would favor the release of O2 to the tissues, increasing Hb-O2 affinity would augment arterial O2 5 saturation during hypoxia. This study was designed to test the hypothesis that 6 pharmacologically increasi...

BACKGROUND Cerebral oximetry is a noninvasive bedside technology using near-infrared light to monitor cerebral oxygen saturation (Sco2) in an uncertain mixture of arteries, capillaries, and veins. The present study used frequency domain near-infrared spectroscopy to determine the ratio of arterial and venous blood monitored by cerebral oximetry during normoxia, hypoxia, and hypocapnia. METHOD...

Venturi masks (VMs) and nasal prongs (NPs) are widely used to treat acute respiratory failure (ARF) in chronic obstructive pulmonary disease (COPD). In this study, these devices were compared in terms of their potentiality to worsen respiratory acidosis and their capacity to maintain adequate (> 90%) arterial oxygenation (Sa,O2) through time (approximately 24 h). In a randomized cross-over stud...

To determine sleep effects on baro- and ventilatory responses to transient chemo- and barostimulation in African-Americans and Caucasians, 26 nonobese normotensive young subjects (13 African-Americans and 13 Caucasians) were studied awake and in non-rapid-eye movement (NREM) and rapid-eye-movement sleep during induced transient hypoxemia (N2), hypertension (phenylephrine, PE), and concomitant h...

The contribution of pH to exercise-induced arterial O2 desaturation was evaluated by intravenous infusion of sodium bicarbonate (Bic, 1 M; 200-350 ml) or an equal volume of saline (Sal; 1 M) at a constant infusion rate during a "2,000-m" maximal ergometer row in five male oarsmen. Blood-gas variables were corrected to the increase in blood temperature from 36.5 +/- 0.3 to 38.9 +/- 0.1 degrees C...

introduction: breathing rehabilitation techniques are designed to reduce symptoms, decrease disability, increase participation in physical and social activities, and improve the overall quality of life for individuals with chronic respiratory disease. however, the role of these techniques remains unclear. this study examined the effects of pursed-lip breathing (plb) education on the respiratory...

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...