Effects of carbon monoxide inhalation in the exergy behaviour of the human body

The present study aimed to evaluate the effects of carbon monoxide inhalation in the behavior of the respiratory system. It is relevant, because carbon monoxide is one of the most common atmospheric pollutants in large urban centers. And an increased rate of exergy destruction can be associated with a shorter life expectancy. In order to do so, a previously developed model for the human respiratory system was used. This model evaluates the concentrations of oxygen, carbon dioxide and carbon monoxide in different respiratory system tissues. There were three main cases of study: an average man adapted to different altitudes, the effect of the different severities of anemia and a pregnancy. In the latter case, the gas exchange that occurs in the placenta was modeled. Three models for exergetic analysis were proposed. One of them considered that the gases contained in the blood are fully dissolved and that they behave as ideal gases. This method resulted in greater efficiency with the increase of carbon monoxide concentration in the atmosphere. The second analysis considered the carrying methods of the gases and it evaluated the exergy associated. The exergy destruction rate increased with CO poisoning. A third analysis were performed, considering just the gas pressures in the different compartments and evaluating the intrinsic entropy production of a gas exchange with finite pressure difference. This analysis led to an increase in the rate of exergy destruction in the presence of monoxide. It is interesting to verify that the last two analysis give similar results, probably being more appropriate (AU)