The cerebral metabolic rate of oxygen (CMRO2) is a physiological parameter closely linked to neural activation as well as to various disease states. Hypercapnic calibration is used to calibrate the BOLD-CBF-CBV relationship under the assumption of iso-metabolic blood flow increase during CO2 inhalation [1]. At the same time, simultaneous measurements of cerebral blood volume (CBV), hemoglobin o...

background: various studies are seeking to find new methods to improve techniques of laryngeal mask airway (lma) insertion and reduce possible complications. in this study, we embarked on a clinical study to investigate the advantages of a new insertion method of laryngeal mask and to compare it with the classic method. materials and methods: two hundred patients aged 20-60 years old in 2012 we...

BACKGROUND The authors examined the notion that a reduction in succinylcholine dose from 1 mg/kg to approximately 0.6 mg/kg would allow a faster recovery of spontaneous ventilation and reduction in the incidence of hemoglobin desaturation during the period of apnea in simulated complete upper airway obstruction situations. METHODS This prospective, randomized, double-blind study involved 60 p...

Since Van Slyke (1) originally described a gasometric method for the determination of hemogIobin by analysis of the oxygen-combining power of blood, it has been the practice to saturate the blood with air at atmospheric pressure in a separate vessel and to transfer a sample of the aerated blood to the gas analyzing apparatus. A method is described here which requires less time, material, and ap...

Ascites syndrome (AS) is manifested in flocks of contemporary broilers that are allowed to fully manifest their genetic potential for rapid growth. After successful selection, a pair of divergent lines was established, AS-susceptible (AS-S) and AS-resistant (AS-R). These lines facilitate comparisons between genetically resistant and susceptible healthy young broilers when reared under standard ...

OBJECTIVES to study the physiological changes, as well as the psychosedative and analgesic effects of nitrous oxide, in experimental conditions. STUDY DESIGN 101 dental students volunteers participated in a single nitrous oxide sedation session without dental treatment. Signs and symptoms were registered during and after the procedure. Pulse rate and hemoglobin oxygen saturation were monitore...

STUDY OBJECTIVES To analyze gender differences in the oxygen transport system at peak exercise with particular emphasis on the difference in systemic arteriovenous oxygen extraction and in mixed venous oxygen saturation. PATIENTS AND METHODS Cardiopulmonary graded exercise testing and hemodynamic assessment were performed on a cycle ergometer in 64 hypertensive patients (32 female and 32 male...

PURPOSE Glaucoma may involve disturbances in retinal oxygenation and blood flow. The purpose of this study was to measure the effect of glaucoma filtration surgery on retinal vessel oxygen saturation. METHODS A noninvasive spectrophotometric retinal oximeter was used to measure hemoglobin oxygen saturation in retinal arterioles and venules before and after glaucoma filtration surgery. Twenty-...

OBJECTIVE Previous work has found cerebral oxygen extraction to decrease during hypothermic cardiopulmonary bypass in children. To elucidate cardiopulmonary bypass factors controlling cerebral oxygen extraction, we examined the effect of perfusate temperature, pump flow rate, and hematocrit value on cerebral hemoglobin-oxygen saturation as measured by near infrared spectroscopy. METHODS Forty...

The polarographic current of whole blood is in excess of that given by plasma at the same oxygen tension. The magnitude of this difference depends on (a) the oxygen content of the sample and thus is determined by the red blood cell content and by the state of oxygen saturation of hemoglobin, and (b) on the rate of dissociation of oxyhemoglobin and therefore is influenced by changes in pH, pCO(2...