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Pericardiocentesis is the removal of fluid from the pericardial space surrounding the heart. The fluid is usually aspirated with a needle and syringe. Occasionally, a catheter is placed within the pericardium or a surgical approach is used. This may be performed for diagnosis, to obtain pericardial fluid; to relieve a pericardial effusion and improve cardiac output; or as a lifesaving measure to relieve a cardiac tamponade. The technique is relatively simple to perform yet has a significant rate of complications.
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Since humanity's earliest times, penetrating cardiac injuries have held a dramatic place in both romantic and medical literature.1–8 In 1649, Riolanus first described pericardial tamponade.3 He noted that an abundance of moisture is collected therein [the pericardium], which causes suffocation, and overwhelms the heart. In 1827, Thomas Jowett described the first use of pericardiocentesis as an intervention for pericarditis.4 In 1829, Baron Larrey, Napoleon's Surgeon, is reported to have performed the first successful pericardiocentesis.5 By 1939, Bigger had suggested that some patients with cardiac tamponade could be managed with pericardial tubes alone, with prompt operation for recurrence.7
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Anatomy of the Heart and Pericardium
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The pericardium is an inverted cone-shaped sack surrounding the heart and lying on top of the diaphragm (Figure 36-1). The inner portion, or visceral pericardium, is a single layer of mesothelial cells covering the epicardium. The outer layer is composed of a dense outer fibrous tissue with an inner layer of mesothelial cells known as the parietal pericardium. The fibrous pericardium is attached to the central tendinous portion of the diaphragm inferiorly. Superiorly, the outer fibrous layer blends with the sheath covering the great vessels. Anteriorly, it attaches to the posterior surface of the sternum. Posteriorly, it is attached to the thoracic vertebral column, esophagus, bronchi, and aorta.
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The heart is contained within the pericardial sac (Figure 36-1B). Numerous portions of the heart are exposed behind the anterior chest wall (Figure 36-2). This includes the right ventricle, left ventricle, right atrium, left atrium, aorta, pulmonary artery, and inferior vena cava (IVC). These structures are vulnerable to injury behind the anterior chest wall9,10 (Table 36-1). The surface area that each of these structures contributes to the anterior cardiac silhouette is also listed in this table. These numbers reflect, roughly, the anatomic incidence of injury with cardiac trauma.11 Traumatic injury to any of these structures can result in a pericardial effusion and cardiac tamponade.
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