The indirect Coombs' test is done on a sample of the liquid part of the blood. It detects antibodies that are present in the bloodstream and could bind to certain red blood cells and destroy them. A Coombs' test involves taking a sample of blood.
It is placed in the middle of the chest or thoracic cavity (middle mediastinum), posterior to the body of sternum and the second to sixth costal cartilages and anterior to the fifth to the eighth thoracic vertebrae.
Where is my heart located exactly? The heart itself is only the size of a fist, and itâs exact location is behind the breastbone (sternum) and slightly to the left of center, as you can see in the diagram above. So if you are looking down at your body, place your hand right in the center of your chest.