Pulse oximetry is a simple, cheap, and noninvasive procedure used to measure the level of oxygen (or oxygen saturation) in the blood. Oxygen saturation should always be above 95 percent. However, oxygen saturation may be lower if you have a respiratory disease or congenital heart disease.
Definition of pericardium. plural. pericardia. play \-dÄ-É\. 1 : the conical sac of serous membrane that encloses the heart and the roots of the great blood vessels of vertebrates. 2 : a cavity or space that contains the heart of an invertebrate and in arthropods is a part of the hemocoel.
The pericardium is a fibroserous double-walled sac that encloses the heart, the pericardial fluid and the roots of the great vessels and is situated within the middle mediastinum.