Pericardiocentesis is the removal of fluid from the pericardial space. This is usually performed using a needle and syringe. A pericardial catheter can be placed for ongoing removal of fluid from within the pericardium. Pericardiocentesis may be performed to obtain pericardial fluid for analysis, to relieve the pressure of a pericardial effusion, to 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.1
Penetrating chest injuries and their subsequent outcomes have been described in the romantic and medical literature for centuries. Cardiac tamponade was first described by Riolanus as early as 1649, with pericardiocentesis described in 1827 by Thomas Jowett as an intervention for pericarditis.2-9 In 1829, Baron Larrey, Napoleon’s Surgeon, is reported to have performed the first successful pericardiocentesis.6 By 1939, Bigger had suggested that some patients with cardiac tamponade could be managed with pericardial tubes alone with prompt operation for recurrence.8
ANATOMY AND PATHOPHYSIOLOGY
ANATOMY OF THE HEART AND PERICARDIUM
The pericardium is an inverted cone-shaped sack surrounding the heart that sits atop the diaphragm (Figure 48-1).10 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. The outer fibrous layer blends superiorly with the sheath covering the great vessels. It attaches anteriorly to the posterior surface of the sternum. It is attached posteriorly to the thoracic vertebral column, esophagus, bronchi, and aorta.
The pericardium. A. Relationship of the pericardium to the major thoracic structures. B. Midsagittal section through the heart and pericardium. C. Cross-section through the thorax. AIA, anterior interventricular artery; RCA, right coronary artery. D. Sagittal section through the thorax. (Used with permission from reference 10.)
The pericardial cavity is a potential space between the visceral and parietal layers of the pericardium. It normally contains up to 50 mL of fluid that acts as a lubricant to the motion of the heart.11 There are a variety of conditions that result in excess fluid in the pericardial space, which require drainage. The estimated causes and relative frequencies of pericardial effusions are listed in Table 48-1.12-18
TABLE 48-1The Etiologies and Relative Frequencies of Pericardial Effusions