CONGESTIVE HEART FAILURE
Congestive heart failure (CHF) is an example of decompensation, or severeheart disease. Heart failure is caused by conditions that damage the heart muscle, including coronary artery disease (CAD), heart attack, cardio-myopathy, valve disease, heart defects present at birth, diabetes mellitus,and chronic renal disease. Heart failure can also occur if several diseases or conditions are present. In this situation, when damage is extreme and the heart cannot provide adequate circulation, the amount of oxygen taken in is insufficient for body needs. Shortness of breath is common, and chest pain can occur on exertion.
Because of the reduced circulation, tissues retain fluid that would normally be carried off by the blood. Sodium builds up, and more fluid is retained, resulting in edema. In an attempt to compensate for this pumping deficit, the heart beats faster and enlarges. This adds to the heart’s burden. In advanced cases when edema affects the lungs, death can occur.
With the inadequate circulation, body tissues do not receive sufficient amounts of nutrients. This insufficiency can cause malnutrition and under-weight, although the edema can mask these problems. In some cases a fluid restriction may be ordered.
Diuretics to aid in the excretion of water and sodium and a sodium-restricted diet are typically prescribed. Because diuretics can cause an excessive loss of potassium, the client’s blood potassium should be carefully monitored to prevent hypokalemia, which can upset the heartbeat. Fruits, especially oranges, bananas, and prunes, can be useful in such a situation because they are excellent sources of potassium and contain only negligible amounts of sodium (Table 18-4). When necessary, the physician will prescribe supplemen-tary potassium.