Breathing 100% O2 at 1 atmosphere absolute (ATA) is known to be associated with a decrease in cerebral blood flow (CBF). It is also accompanied by a fall in arterial Pco2 leading to uncertainty as to whether the cerebral vasoconstriction is totally or only in part caused by arterial hypocapnia. We tested the hypothesis that the increase in arterial Po2 while O2 was breathed at 1.0 ATA decreases...

PURPOSE The purpose of this study was to determine arterial blood gases, the mechanical limits for generating expiratory flow and the work performed by the respiratory muscles during treadmill exercise in Kenyan runners. METHODS Kenyan runners (10 men and 4 women; mean ± SD age = 25.2 ± 1.3 yr) were instrumented with a radial artery catheter, an esophageal balloon-tipped catheter, and an esop...

The effect of acute or short-term hypoxia on fetal cardiovascular hemodynamics has been well known; however, little is known about the effect of long-term hypoxemia. To determine the fetal hemodynamic responses to this stress we studied two groups of animals: 1) pregnant ewes (n = 20) at 110-115 days of gestation subjected to hypoxia for up to 28 days and 2) pregnant ewes (n = 4) that served as...

Tonsils are located in the upper airway.serious complications may threaen the patients during and following surgical operations in this area.this study was done to assess the effectiveness of local lidocaine infiltration for redusing complications of tonsillectomy.in this study,74 patients were randomly selected.37 patients received local lidocaine infiltration(2ml of 2% lidocaine)in the tonsil...

Several publications have reported effects of hypobaric conditions in patients with chronic obstructive pulmonary disease. To the current authors' knowledge, similar studies concerning patients with restrictive lung disease have not been published. The effect of simulated air travel in a hypobaric chamber on arterial blood gases, blood pressure, and cardiac frequency during rest and 20 W exerci...

OBJECTIVE To reproduce the surgery for correction of pulmonary valve anomalies using right heart bypass and a new bicaval cuffed venous cannula for minimal access surgery. METHODS Fifteen Large-White pigs were used for this study. The standard technique model was established with the first five pigs, the experiment was done with nine animals by sternotomy, and one was submitted to a minimally...

conclusions closed suction caused fewer disturbances in patients’ hemodynamic condition, took shorter time, and is more economical. therefore, this method can replace open suction method in caring of severely critically ill patients. results no significant differences were observed between the two suctioning methods in terms of mean systolic blood pressure (p = 0.075), diastolic blood pressure ...

The effect of sustained moderate hypoxia on renal blood flow and renal function was studied in the ovine fetus (123-129 days). The experiments consisted of 48 h of isocapnic hypoxia, not resulting in acidemia, but sufficient to produce redistribution of blood flow in favor of the brain at the expense of the carcass. Hypoxemia was induced by maternal nitrogen inhalation. Fetal arterial O2 satura...

Nielsen, H. B., R. Boushel, P. Madsen, and N. H. Secher. Cerebral desaturation during exercise reversed by O2 supplementation. Am. J. Physiol. 277 (Heart Circ. Physiol. 46): H1045–H1052, 1999.—The combined effects of hyperventilation and arterial desaturation on cerebral oxygenation (ScO2) were determined using near-infrared spectroscopy. Eleven competitive oarsmen were evaluated during a 6-min...

The objective with this study is to develop and calibrate an invasive data logger to measure muscle O2 saturation in large, freely diving whales. We intend to use this data logger to measure muscle O2 saturation and determine how blood flow to muscle is altered during diving. These data will be important to determine if muscle blood flow is reduced during diving, and important to estimate how t...