This review gives an account of some of the factors affecting the transport of oxygen from the lungs until its final discharge in the tissues. The sequence of physiological and metabolic processes to be described may be considered collectively as the 'coarse adjust-ment' of oxygen transport. The 'fine adjustment' will be discussed in the succeeding chapter which surveys the local factors influe...

Coronary sinus oxygen saturation was measured continuously during incremental atrial pacing in 34 patients undergoing cardiac catheterisation. In eleven patients with normal coronary arteriograms, negative exercise tests, and no ST segment depression on the electrocardiogram, an increase in the rate of atrial pacing transiently decreased coronary sinus oxygen saturation but within 20 s oxygen s...

We report a case of rheumatic heart disease with severe mitral stenosis having cyanosis and low oxygen saturation on pulse oximetry. The findings of clinical examination and low values on pulse oximetry were inconsistent with the findings of normal partial pressure of oxygen and oxygen saturation on arterial blood gas analysis, leading to diagnostic dilemma. In such clinical scenario, the anest...

OBJECTIVES The purpose of this study was to test if venous blood drawn from femoral access can be used to estimate the central venous oxygen saturation and arterial lactate levels in critically ill patients. METHODS Bland-Altman analysis and Spearman correlations were used to compare the femoral venous oxygen saturation and central venous oxygen saturation as well as arterial lactate levels a...

background : mechanical ventilation is used for some infants in neonatal intensive care units (nicu) due to many physiological and clinical causes. since these patients have endotracheal tubes, cleaning and keeping the airways open through suctioning should be done to increase oxygenation. this study aimed to evaluate effect of open and closed suctioning methods on respiratory parameters of inf...

Pulse oximetry probes placed peripherally may fail to give accurate values of blood oxygen saturation when the peripheral circulation is poor. Because central blood flow may be preferentially preserved, we investigated the oesophagus as an alternative monitoring site. A reflectance blood oxygen saturation probe was developed and evaluated in 49 patients undergoing cardiothoracic surgery. The oe...

Normal inclividuals breathing pure oxygen obtain full saturation of their hemoglobin, whereas those with right to left shunts do not. Oxygen hemoglobin dissociation curves indicate that increases to full oxygen saturation of hemoglobin are accompanied by marked increases of the oxygen tension. WVhen breathing oxygen fails to produce full saturation, relatively little change in oxygen tension oc...

We combine two near-infrared diffuse optical techniques to study variations of blood flow, haemoglobin concentration, and blood oxygen saturation in the functioning rat brain. Diffuse correlation spectroscopy (or flowmetry) monitors changes in the cerebral blood flow, without the use of the principles of tracer clearance, by measuring the optical phase-shifts caused by moving blood cells. Near-...