32 / 56
44
Chapter 2
•
Cardiovascular Care
INFECTIOUS/INFLAMMATORY DISORDERS
PERICARDIAL DISEASES
The pericardial space normally
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.
Pericardial tissue damaged by bacteria or other substances releases
chemical mediators of inflammation into the surrounding tissue.
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.
Endocardium Myocardium Epicardium Fibrous
pericardium
Inflamed
parietal
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