In adult mammals, arterial blood gases closely reflect lung gas composition, and arterial blood gases can, therefore, be effectively regulated through changes in ventilation. This is not the case among most ectothermic vertebrates, where the systemic and pulmonary circulations are not completely separated, resulting in central vascular shunts. In the presence of a right-to-left shunt (R-L shunt...

background: abnormal umbilical cord ph can be indicated a distress imposed of newborn and can also be useful in determining the prognosis of the newborn. there are different views about the effect of the neonatal delivery method on the blood gas analysis of the umbilical artery. this study aimed to determine the effect of the method of delivery on umbilical artery ph. methods: in this cross –se...

Although the naturally occurring atmospheric noble gases He, Ne, Ar, Kr, and Xe possess great potential as tracers for studying gas exchange in living beings, no direct analytical technique exists for simultaneously determining the absolute concentrations of these noble gases in body fluids in vivo. In this study, using human blood as an example, the absolute concentrations of all stable atmosp...

Gas bubbles of oxygen. carbon dioxide and nitrogen are injected into the degassed plasma and whole blood. The bubble size is measured at time intervals until the bubble is completely dissolved in the liquid. Physical quantities governing the dissolution of gas bubbles are identified and their effects are examined. The applications of the study include the dissolution of gas emboli in human body...

Two models of heparin coated, hollow fiber membrane oxygenators were tested in vitro to compare gas transfer and transoxygenator pressure drop using an established protocol. Oxygen and carbon dioxide transfer rates were measured at blood flows of 2.5 and 5.0 liters per minute with gas flow: blood flow ratios of 1:1 and 2:1 at both blood flows. All testing was performed under normothermic condit...

Considerable interest has been shown in recent years in the relative distributions of alveolar blood and gas flows under various conditions. During thoracic surgical procedures in the lateral position, with one hemithorax open and with controlled ventilation of the lungs, a severe degree of maldistribution of blood and gas may be expected. The upper lung may be freely expanded, retracted by the...

In 1953, the doctor draft interrupted Dr. Severinghaus' anesthesia and physiology training and sent him to the National Institutes of Health as director of anesthesia research at the newly opened Clinical Center. He developed precise laboratory partial pressure of carbon dioxide (PCO(2)) and pH analysis to investigate lung blood gas exchange during hypothermia. Constants for carbon dioxide solu...

Large differences between the concentrations of serum total carbon dioxide (TCO2) and blood gas bicarbonate (HCO3 (-)) were observed in two consecutive simultaneously drawn sets of samples of serum and arterial blood gases in a patient who presented with severe carbon dioxide retention and profound acidemia. These differences could not be explained by the effect of the high partial pressure of ...