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ANEMIA

ANEMIA

Anemia, per se, is not a specific disease state but a sign of an underlying disorder. It is by far the most common hematologic condition. Anemia, a condition in which the hemoglobin concentration is lower than normal, reflects the presence of fewer than normal RBCs within the circulation. As a result, the amount of oxygen delivered to body tissues is also diminished. There are many different kinds of anemia, but ll can be classified into three broad etiologic categories:

 

  • Loss of RBCs—occurs with bleeding, potentially from any major source, such as the gastrointestinal tract, the uterus, the nose, or a wound.

Decreased production of RBCs—can be caused by a deficiency in cofactors (including folic acid, vitamin B12, and iron) required for erythropoiesis; RBC production may also be reduced if the bone marrow is suppressed (eg, by tumor, medications, toxins) or is inadequately stimulated because of a lack of erythropoietin (as occurs in chronic renal disease)

 

• Increased destruction of RBCs—may occur because of an overactive RES (including hypersplenism) or because the bone marrow produces abnormal RBCs that are then destroyed by the RES (eg, sickle cell anemia). A conclusion as to whether the anemia is caused by destruction or by inadequate production of RBCs usually can be reached on the basis of the following factors:

 

• The marrow’s ability to respond to the decreased RBCs (as evidenced by an increased reticulocyte count in the circulating blood)

 

• The degree to which young RBCs proliferate in the bone marrow and the manner in which they mature (as observed on bone marrow biopsy)

 

• The presence or absence of end products of RBC destruction within the circulation (eg, increased bilirubin level, decreased haptoglobin level)

 

Classification of Anemias

Anemia may be classified in several ways. The physiologic approach is to determine whether the deficiency in RBCs is caused by a defect in their production (hypoproliferative anemia), by their destruction (hemolytic anemia), or by their loss (bleeding). In the hypoproliferative anemias, RBCs usually survive normally, but the marrow cannot produce adequate numbers of these cells. The decreased production is reflected in a low reticulocyte count. Inadequate production of RBCs may result from marrow damage due to medications or chemicals (eg, chloramphenicol, benzene) or from a lack of factors necessary for RBC formation (eg, iron, vitamin B12, folic acid, erythropoietin). Hemolytic anemias stem from premature destruction of RBCs, which results in a liberation of hemoglobin from the RBC into the plasma. The increased RBC destruction results in tissue hypoxia, which in turn stimulates erythropoietin production. This increased production is reflected in an increased reticulocyte count, as the bone marrow responds to the loss of RBCs. The released hemoglobin is converted in large part to bilirubin; therefore, the bilirubin concentration rises. Hemolysis can result from an abnormality within the RBC itself (eg, sickle cell anemia, glucose-6-phosphatedehydrogenase [G-6-PD] deficiency) or within the plasma (eg, immune hemolytic anemias), or from direct injury to the RBC within the circulation (eg, hemolysis caused by mechanical heart valve).

 

Clinical Manifestations

Aside from the severity of the anemia itself, several factors influence the development of anemia-associated symptoms:

 

• The speed with which the anemia has developed

• The duration of the anemia (ie, its chronicity)

• The metabolic requirements of the individual

• Other concurrent disorders or disabilities (eg, cardiopulmonary disease)

• Special complications or concomitant features of the condition that produced the anemia

 

In general, the more rapidly an anemia develops, the more severe its symptoms. An otherwise healthy person can often tolerate as much as a 50% gradual reduction in hemoglobin without pronounced symptoms or significant incapacity, whereas the rapid loss of as little as 30% may precipitate profound vascular collapse in the same individual. A person who has been anemic for a very long time, with hemoglobin levels between 9 and 11 g/dL, usually has few or no symptoms other than slight tachycardia on exertion and fatigue. Patients who customarily are very active or who have significant demands on their lives (eg, a single, working mother of small children) are more likely to have symptoms, and those symptoms are more likely to be pronounced than in a more sedentary person. A patient with hypothyroidism with decreased oxygen needs may be completely asymptomatic, without tachycardia or increased cardiac output, at a hemoglobin level of 10 g/dL. Similarly, patients with coexistent cardiac, vascular, or pulmonary disease may develop more pronounced symptoms of anemia (eg, dyspnea, chest pain, muscle pain or cramping) at a higher hemoglobin level than those without these concurrent health problems. Finally, some anemic disorders are complicated by various other abnormalities that do not result from the anemia but are inherently associated with these particular diseases. These abnormalities may give rise to symptoms that completely overshadow those of the anemia, as in the painful crises of sickle cell anemia.

 

Assessment and Diagnostic Findings

A variety of hematologic studies are performed to determine the type and cause of the anemia. In an initial evaluation, the hemoglobin, hematocrit, reticulocyte count, and RBC indices, particularly the mean corpuscular volume (MCV), are particularly useful. Iron studies (serum iron level, total iron-binding capacity [TIBC], percent saturation, and ferritin), as well as serum vitamin B12 and folate levels, are also frequently obtained. Other tests include haptoglobin and erythropoietin levels. The remaining CBC values are useful in determining whether the anemia is an isolated problem or part of another hematologic condition, such as leukemia or myelodysplastic syndrome (MDS). Bone marrow aspiration may be performed. In addition, other diagnostic studies may be performed to determine the presence of underlying chronic illness, such as malignancy, and the source of any blood loss, such as polyps or ulcers within the gastrointestinal tract.

 

Complications

General complications of severe anemia include heart failure, paresthesias, and confusion. At any given level of anemia, patients with underlying heart disease are far more likely to have angina or symptoms of heart failure than those without heart disease. Complications associated with specific types of anemia are included in the description of each type.

 

Medical Management

Management of anemia is directed toward correcting or controlling the cause of the anemia; if the anemia is severe, the RBCs that are lost or destroyed may be replaced with a transfusion of packed

RBCs (PRBCs). The management of the various types of anemia is covered in the discussions that follow.

 

NURSING PROCESS:

THE PATIENT WITH ANEMIA

Assessment

The health history and physical examination provide important data about the type of anemia involved, the extent and type of symptoms it produces, and the impact of those symptoms on the patient’s life. Weakness, fatigue, and general malaise are common, as are pallor of the skin and mucous membranes (sclera, oral mucosa). Jaundice may be present in patients with megaloblastic anemia or hemolytic anemia. The tongue may be smooth and red (in iron deficiency anemia) or beefy red and sore (in megaloblastic anemia); the corners of the mouth may be ulcerated (angular cheilosis) in both types of anemia. Individuals with iron deficiency anemia may crave ice, starch, or dirt (known as pica); their nails may be brittle, ridged, and concave.

The health history should include a medication history, because some medications can depress bone marrow activity or interfere with folate metabolism. An accurate history of alcohol intake, including the amount and duration, should be obtained. Family history is important, because certain anemias are inherited. Athletic endeavors should be assessed, because extreme exercise can decrease erythropoiesis and RBC survival in some athletes.

 

A nutritional assessment is important, because it may indicate deficiencies in essential nutrients such as iron, vitamin B12, and folic acid. Children of indigent families may be at higher risk for anemia because of nutritional deficiencies. Strict vegetarians are also at risk for megaloblastic types of anemia if they do not supplement their diet with vitamin B12. Cardiac status should be carefully assessed. When the hemoglobin level is low, the heart attempts to compensate by pumping faster and harder in an effort to deliver more blood to hypoxic tissue. This increased cardiac workload can result in such symptoms as tachycardia, palpitations, dyspnea, dizziness, orthopnea, and exertional dyspnea. Heart failure may eventually develop, as evidenced by an enlarged heart (cardiomegaly) and liver (hepatomegaly) and by peripheral edema.

Assessment of the gastrointestinal system may disclose complaints of nausea, vomiting (with specific questions as to the appearance of any emesis [eg, looks like “coffee grounds”]), melena or dark stools, diarrhea, anorexia, and glossitis (inflammation of the tongue). Stools should be tested for occult blood. Women should be questioned about their menstrual periods (eg, excessive menstrual flow, other vaginal bleeding) and the use of iron supplements during pregnancy.

The neurologic examination is also important because of the effect of pernicious anemia on the central and peripheral nervous systems. Assessment should include the presence and extent of peripheral numbness and paresthesias, ataxia, poor coordination, and confusion. Finally, it is important to monitor relevant laboratory test results and to note any changes over time.

 

Diagnosis

NURSING DIAGNOSES

Based on the assessment data, major nursing diagnoses for the anemic patient may include:

• Activity intolerance related to weakness, fatigue, and general malaise

• Imbalanced nutrition, less than body requirements, related to inadequate intake of essential nutrients

• Ineffective tissue perfusion related to inadequate blood volume or hematocrit

• Noncompliance with prescribed therapy

 

 

COLLABORATIVE PROBLEMS/ POTENTIAL COMPLICATIONS

Based on the assessment data, potential complications that may develop include:

• Heart failure

• Paresthesias

• Confusion

 

Planning and Goals

The major goals for the patient may include increased tolerance of normal activity, attainment or maintenance of adequate nutrition, maintenance of adequate tissue perfusion, compliance with prescribed therapy, and absence of complications.

 

Nursing Interventions

MANAGING FATIGUE

The most frequent symptom and complication of anemia is fatigue. This distressing symptom is too often minimized by health care providers. Fatigue is often the symptom that has the greater negative impact on the individual’s level of functioning and consequent quality of life. Patients describe the fatigue from anemia as oppressive. Fatigue can be significant, yet the anemia may not be severe enough to warrant transfusion. Fatigue can interfere with an individual’s ability to work, both inside and outside the home. It can harm relationships with family and friends. Patients often lose interest in hobbies and activities, including sexual activity.

The distress from fatigue is often related to an individual’s responsibilities and life demands as well as the amount of assistance and support received from others.

Nursing interventions can focus on assisting the patient to prioritize activities and to establish a balance between activity and rest that is realistic and feasible from the patient’s perspective. Patients with chronic anemia need to maintain some physical activity and exercise to prevent the deconditioning that results from inactivity.

 

MAINTAINING ADEQUATE NUTRITION

Inadequate intake of essential nutrients, such as iron, vitamin B12, folic acid, and protein can cause some anemias. The symptoms associated with anemia (eg, fatigue, anorexia) can in turn interfere with maintaining adequate nutrition. A healthy diet should be encouraged. Because alcohol interferes with the utilization of essential nutrients, the nurse should advise the patient to avoid alcoholic beverages or to limit their intake and should provide the rationale for this recommendation. Dietary teaching sessions should be individualized, including cultural aspects related to food preferences and food preparation. The involvement of family members enhances compliance with dietary recommendations.

Dietary supplements (eg, vitamins, iron, folate, protein) may be prescribed as well.

Equally important, the patient and family must understand the role of nutritional supplements in the proper context, because many forms of anemia are not the result of a nutritional deficiency.

In such cases, excessive intake of nutritional supplements will not improve the anemia. A potential problem in individuals with chronic transfusion requirements occurs with the indiscriminate use of iron. Unless an aggressive program of chelation therapy is implemented, these individuals are at risk for iron overload from their transfusions alone. The addition of an iron supplement only exacerbates the situation.

 

MAINTAINING ADEQUATE PERFUSION

Patients with acute blood loss or severe hemolysis may have decreased tissue perfusion from decreased blood volume or reduced circulating RBCs (decreased hematocrit). Lost volume is replaced with transfusions or intravenous fluids, based on the symptoms and the laboratory findings. Supplemental oxygen may be necessary, but it is rarely needed on a long-term basis unless there is underlying severe cardiac or pulmonary disease as well. The nurse monitors vital signs closely; other medications, such as antihypertensive agents, may need to be adjusted or withheld.

 

PROMOTING COMPLIANCE WITH PRESCRIBED THERAPY

For patients with anemia, medications or nutritional supplements are often prescribed to alleviate or correct the condition. These patients need to understand the purpose of the medication, how to take the medication and over what time period, and how to manage any side effects of therapy. To enhance compliance, the nurse can assist patients in developing ways to incorporate the therapeutic plan into their lives, rather than merely giving the patient a list of instructions. For example, many patients have difficulty taking iron supplements because of related gastrointestinal effects. Rather than seeking assistance from a health care provider in managing the problem, some of these patients simply stop taking the iron.

Abruptly stopping some medications can have serious consequences, as in the case of high-dose corticosteroids to manage hemolytic anemias. Some medications, such as growth factors, are extremely expensive. Patients receiving these medications may need assistance with obtaining needed insurance coverage or with exploring alternatives for obtaining these medications.

 

MONITORING AND MANAGING

POTENTIAL COMPLICATIONS

A significant complication of anemia is heart failure from chronic diminished blood volume and the heart’s compensatory effort to increase cardiac output. Patients with anemia should be assessed for signs and symptoms of heart failure. A serial record of body weights can be more useful than a record of dietary intake andoutput, because the intake and output measurements may not be accurate. In the case of fluid retention resulting from congestive heart failure, diuretics may be required. In megaloblastic forms of anemia, the significant potential complications are neurologic. A neurologic assessment should be performed for patients with known or suspected megaloblastic anemia. Patients may initially complain of paresthesias in their lower extremities. These paresthesias are usually manifested as numbness and tingling on the bottom of the foot, and they gradually progress. As the anemia progresses and damage to the spinal cord occurs, other signs become apparent. Position and vibration sense may be diminished; difficulty maintaining balance is not uncommon, and some patients have gait disturbances as well. Initially mild but gradually progressive confusion may develop.

 

Evaluation

EXPECTED PATIENT OUTCOMES

Expected patient outcomes may include:

1. Tolerates activity at a safe and acceptable level

a. Follows a progressive plan of rest, activity, and exercise

b. Prioritizes activities

c. Paces activities according to energy level

2. Attains and maintains adequate nutrition

a. Eats a healthy diet

b. Develops meal plan that promotes optimal nutrition

c. Maintains adequate amounts of iron, vitamins, and protein from diet or supplements

d. Adheres to nutritional supplement therapy when prescribed

e. Verbalizes understanding of rationale for using recommended nutritional supplements

f. Verbalizes understanding of rationale for avoiding non recommended nutritional supplemen