Test Overview
Pericardial drainage (pericardiocentesis) is done to find the cause of
fluid buildup around the heart and to relieve pressure on the heart. The tissue
sac that surrounds the heart is called the
pericardium
. It protects the heart and parts of the
major blood vessels connected to the heart. Normally, there is a small amount
of fluid between this sac and the heart. This fluid surrounds and helps cushion
the heart. It helps reduce friction between the heart and other structures in
the chest when the heart beats.
Some diseases cause fluid to
collect within the pericardium (pericardial effusion). Excess fluid can
prevent normal filling of the heart, which can reduce the heart's ability to
pump blood (cardiac tamponade).
Pericardial drainage
may be done to find the cause of a pericardial effusion. During this test, a
needle is inserted under the breastbone and into the pericardium to remove a
sample of the fluid. The fluid is sent to a laboratory where it is measured and
checked for blood, microorganisms (such as bacteria,
fungi, or viruses),
white blood cells, sugar (glucose), and cancer cells.
In some cases, the pericardial fluid may be checked for other substances (such
as carcinoembryonic antigen, or CEA).
Pericardial drainage may
also be done to help relieve pressure on the heart. It is sometimes done in an
emergency if a serious injury has occurred, such as a gunshot or stab wound to
the chest or a massive
heart attack. In these circumstances, blood or fluid
can build up very rapidly in the
pericardium. An emergency pericardial drainage can be
done to remove the blood or excess pericardial fluid surrounding the
heart.