IPLab:Lab 4:Pulmonary Congestion and Edema

Clinical Summary

This 69-year-old white male with well-controlled Type I diabetes mellitus (insulin-dependent) presented with upper abdominal and lower chest pain of four hours duration and accompanied by shortness of breath and diaphoresis. An electrocardiogram revealed multiple premature ventricular contractions (PVCs). The hospital course was characterized by recurrent pulmonary edema and oliguria. The terminal event was cardiac arrest.

Autopsy Findings

Significant findings at postmortem examination were old and recent myocardial infarctions and evidence of congestive heart failure. The right and left lungs weighed 950 grams and 750 grams, respectively, and were reddish-brown.

Images

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  This is a gross photograph of lungs that are distended and red. The reddish coloration of the tissue is due to congestion. Some normal pink lung tissue is seen at the edges of the lungs (arrows).
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  This is a gross photograph of lung demonstrating acute pulmonary congestion and edema. A frothy exudate fills the bronchus (arrow).
• 
  This gross photograph demonstrates the frothy exudate that is being extruded from the lung tissue.
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  This is a low-power photomicrograph of lung from this case. The lung section has a pale-red color indicating proteinaceous material within the lung.
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  This is a higher-power photomicrograph of lung. The edema fluid within the alveoli is visible at this higher magnification (arrows). The thickened pleura (1) is on the left.
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  This is a higher-power photomicrograph showing edema-filled alveoli in the right portion of this section (arrows).
• 
  This high-power photomicrograph illustrates the edema fluid within the alveoli (1) and the congestion (RBCs) in the alveolar capillaries (arrows).

Study Questions

• Name two types of edema fluid.

Inflammatory edema has a higher protein content (specific gravity > 1.020) and is associated with an inflammatory reaction. Noninflammatory edema is caused by alterations in hemodynamic forces across the capillary wall (hemodynamic edema).

• Define the following:

• anasarca

Anasarca: severe and generalized edema which includes marked swelling of the subcutaneous tissues.

• hydrothorax

Hydrothorax: fluid build-up in the thorax.

• hydropericardium

Hydropericardium: fluid build-up in the pericardial sac.

• hydroperitoneum

Hydroperitoneum: fluid accumulation in the abdominal cavity--also referred to as ascites.

• What is the most common cause of pulmonary edema?

Left-sided heart failure.

Shortness of breath is a common clinical manifestation of heart failure.

Diaphoresis is a profuse perspiration often seen during a myocardial infarction.

Premature ventricular contractions (PVCs) are a common cardiac arrhythmia. They are present even in healthy individuals, for whom no treatment is indicated. However, in patients with heart disease, PVCs can be significant indicators of disease processes. For example, increased numbers of PVCs are common following an acute myocardial infarction.

Pulmonary edema refers to the accumulation of fluid in the pulmonary alveolar and tissue spaces as a result of changes in capillary permeability and/or increases in capillary hydrostatic pressure.

Oliguria is the occurrence of decreased urine output.

Cardiac arrest is the sudden standstill of cardiac function.

A normal right lung weighs 450 grams (range: 360 to 570 grams.

A normal left lung weighs 375 grams (range: 325 to 480 grams).

Pulmonary congestion is the engorgement of pulmonary vessels with blood. The increased pressure caused by this engorgement leads to transudation of fluid through the capillary walls and into the alveolar and interstitial spaces.