Lipp Vis Nursing ChaptLWBK1630_C02_p013-068

44  Chapter 2 • Cardiovascular Care

INFECTIOUS/INFLAMMATORY DISORDERS PERICARDIAL DISEASES The pericardial space normally

Pericardial tissue damaged by bacteria or other substances releases chemical mediators of inflammation into the surrounding tissue.

contains 50 mL of thin, clear, straw colored fluid in the pericardial sac, which lubricates the layers of the heart and reduces friction when the heart contracts. Pericarditis is an inflammation of the pericardium, the membranous sac enveloping the heart. Pericarditis is the most common disease of the pericardium encountered in clinical practice. Diseases of the pericardium present clinically in one of several ways: • Acute, subacute pericarditis • Chronic, recurrent pericarditis • Pericardial effusion • Cardiac tamponade • Constrictive pericarditis • Effusive-constrictive pericarditis • Cardiac masses Clinical Manifestations of Pericarditis • Pleuritic chest pain • Pericardial rubs • Widespread ST-segment elevation • Pericardial effusion Treatment of Pericarditis • Targeted at the specific cause as much as possible. • Aspirin or a nonsteroidal anti- inflammatory drug (NSAID) should be considered as first-line therapy in most cases. PERICARDIAL EFFUSION Pericardial effusion is an abnormal accumulation of fluid in the pericardial cavity. Since there is limited space in the pericardial cavity, fluid accumulation leads to an increased pressure which can negatively affect heart function. Pericardial disorders include any process that inflames, injures, or reduces lymphatic drainage of the pericardium. The prognosis for individuals with pericardial effusion depends on the cause and size.

Friction occurs as the inflamed pericardial layers rub against each other.

Histamines and other chemical mediators dilate vessels and increase vessel permeability.

Fluids and proteins (including fibrinogen) leak into the tissue causing extracellular edema. Macrophages, neutrophils, and monocytes in the tissue begin to phagocytose the invading bacteria.

Gradually, the space fills with an exudate composed of necrotic tissue, dead neutrophils, and macrophages. These products are eventually absorbed into healthy tissue.

Inflamed parietal pericardium

Endocardium Myocardium Epicardium Fibrous pericardium

Clinical Manifestations • Chest pain—Typically sharp and pleuritic, improved by sitting up and leaning forward • Pericardial friction rub • ECG changes—New widespread ST elevation or PR depression • Pericardial effusion

Nursing Considerations • Stress the importance of adequate rest and rest periods in between activities of daily living. • To reduce anxiety, allow the patient to express his concerns about the effects of activity