Pericardial Disease in the Intensive Care Setting

Pericardial disease commonly occurs in the intensive care setting, but its timely diagnosis may be missed. The normal pericardium serves as a lubricated sac within which the heart may beat with minimal friction. The effect of the pericardium on cardiac filling at normal diastolic pressures is not clear; however, it may limit cardiac dilation in states of acute volume overload such as mitral regurgitation and right ventricular infarction.

Pericardial disease may be divided into two catego ries : those cases that result from inflammation of the pericardium (pericarditis), and those cases in which a pericardial effusion or the thickened pericardium itself causes hemodynamic changes (tamponade and constric tion). Simple pericarditis should not lead to any hemo dynamic alteration other than tachycardia. In both tam ponade and constriction, the jugular venous pressure is elevated with low forward cardiac output; tamponade typically shows pulsus paradoxus, whereas constric tion more frequently shows Kussmaul's sign.

The electrocardiogram may show diffuse ST segment elevation with PR segment depression in pericarditis; a large pericardial effusion, even with early tamponade, may not by itself cause any changes in the electrocar diogram. The echocardiogram is invaluable in diagnos ing the presence of a pericardial effusion and recogniz ing tamponade physiology (diastolic collapse of the right ventricular outflow tract and invagination of the right atrium).

In selected patients, simple pericarditis may be managed outside of the hospital. Anyone suspected of having a hemodynamically significant pericardial effu sion should be hospitalized, usually in an intensive care unit. Pericardiocentesis should be performed under op timal monitoring conditions, although in an emergency, blind pericardiocentesis may be attempted. Recognition of the cause of the pericardial process will guide its treatment. Management of selected pericardial syn dromes is discussed later in this review.