Final answer:
We take samples of Pa and Ao saturation during a right heart cath to assess the heart's function and the lungs' ability to oxygenate the blood, which is important for diagnosing heart conditions. These measurements help detect shunts and problems with oxygen exchange, providing essential information beyond what non-invasive methods like pulse oximetry can offer.
Step-by-step explanation:
We take samples of pulmonary artery (Pa) and aortic (Ao) saturation during a right heart catheterization to assess the levels of oxygen in different parts of the heart and lungs. This is important to diagnose and manage various heart conditions. Using a device known as a pulse oximeter, we can monitor the percent saturation of oxygen in the blood. However, this non-invasive method may not always provide the complete picture. Therefore, during a right heart cath, direct measurements of oxygen saturation from blood samples are taken, which provide more accurate and specific information about the heart's function and the lungs' ability to oxygenate the blood.
During right heart catheterization, blood samples from the right side of the heart (pulmonary artery) and from the systemic arterial blood (aorta) can help detect shunts (abnormal passages of blood between the cardiac chambers or vessels) or problems with oxygen exchange in the lungs. For instance, a detection of a higher oxygen saturation in the pulmonary artery than what is expected can suggest a left-to-right shunt. The differentiation of Pa and Ao saturations can be crucial for planning treatment or surgery.
Normal oxygen saturation levels, measured as partial pressure of oxygen (pO2), are essential to ensure that the tissues receive adequate oxygen. Lower percentages indicate hypoxemia or low blood oxygen level, which can lead to a state of hypoxia where the body's tissues are oxygen-deprived.