Cardiac tamponade, also known as pericardial tamponade, is when fluid in the pericardium (the sac around the hea) builds up, resulting in compression of the hea.Onset may be rapid or gradual. Symptoms typically include those of cardiogenic shock including shoness of breath, weakness, lightheadedness, and cough. Other s relate to the underlying cause Cardiac tamponade is caused by a large or uncontrolled pericardial effusion, i.e. the buildup of fluid inside the pericardium.This commonly occurs as a result of chest trauma (both blunt and penetrating), but can also be caused by myocardial rupture, cancer, uremia, pericarditis, or cardiac surgery, and rarely occurs during retrograde aoic dissection,or while the person is taking anticoagulant therapy.The effusion can occur rapidly (as in the case of trauma or myocardial rupture), or over a more gradual period of time (as in cancer). The fluid involved is often blood, but pus is also found in some circumstances. Causes of increased pericardial effusion include hypothyroidism, physical trauma (either penetrating trauma involving the pericardium or blunt chest trauma), pericarditis (inflammation of the pericardium), iatrogenic trauma (during an invasive procedure), and myocardial rupture. Surgery One of the most common settings for cardiac tamponade is in the first 24 to 48 hours after hea surgery. After hea surgery, chest tubes are placed to drain blood. These chest tubes, however, are prone to clot formation. When a chest tube becomes occluded or clogged, the blood that should be drained can accumulate around the hea, leading to tamponade Ref Davidson 23rd edition pg 460