The fetal lungs are collapsed, and blood passes from the right atrium directly into the left atrium through the foramen ovale: an open conduit between the paired atria, or through the ductus arteriosus: a shunt between the pulmonary artery and the aorta.
By Deborah Leader, RN. Updated January 21, 2016. Hypercapnia is a condition that occurs when there is too much carbon dioxide in the blood. While it is sometimes caused by things such as hypoventilation or a narcotic drug overdose, a much more common cause is COPD. If you have COPD, it's important to know the hypercapnia symptoms, as well as the treatments available.
On the other hand, carbon monoxide is the result of incomplete combustion in the carâs engine which in turn can cause high levels of oxygen. Common Reasons. There are certain causes of gas related smog check failures for each of these gases. Common causes of high levels of NOx or Nitrogen Oxides include advance timing and a faulty EGR system. The EGR System or Exhaust Gas Recirculation System is the main component in the exhaust gas recirculation system.