A reduction in the mass of circulating red blood cells. People are considered anemic when their hemoglobin levels are more than two standard deviations below the mean level in their hospital's laboratory. The diagnosis of anemia is influenced by variables such as the patient's age (neonates are anemic at levels of hemoglobin that would be considered polycythemic in some adults), gender (men have higher hemoglobin levels than women), pregnancy status (hemodilution in pregnancy lowers measured hemoglobin), residential altitude, and ethnic or racial background. anemic (ă-nē′mik), adj. anemically (ă-nē′mi-k(ă-)lē), adv. Symptomatic anemia exists when hemoglobin content is less than that required to meet the oxygen-carrying demands of the body.
If anemia develops slowly, however, there may be no functional impairment even though the hemoglobin is less than 7 g/100/dL of blood.Anemia is not a disease but rather a symptom of other illnesses. It is classified on the basis of mean corpuscular volume as microcytic (80), normocytic (80-94), and macrocytic (>94); on the basis of mean corpuscular hemoglobin as hypochromic (27), normochromic (27-32), and hyperchromic (>32); and on the basis of etiological factors.
- Anemia may be caused by bleeding, e.g., from the gastrointestinal tract or the uterus; vitamin or mineral deficiencies, esp. vitamin B12, folate, or iron; decreases in red blood cell production, e.g., bone marrow suppression in kidney failure or bone marrow failure in myelodysplastic syndromes; increases in red blood cell destruction as in hemolysis due to sickle cell anemia; or increases in red blood cell sequestration by the spleen (as in portal hypertension), or administration of toxic drugs (as in cancer chemotherapy).
- Anemic patients may experience weakness, fatigue, lightheadedness, breathlessness, palpitations, angina pectoris, and headache. Signs of anemia may include a rapid pulse or rapid breathing if blood loss occurs rapidly. The chronically anemic may have pale skin, mucous membranes, or nail beds and fissures at the corners of the mouth.
- Treatment of anemia must be specific for the cause. The prognosis for recovery from anemia is excellent if the underlying cause is treatable.
Anemia due to excessive blood loss: For acute blood loss, immediate measures should be taken to stop the bleeding, to restore blood volume by transfusion, and to combat shock.
Chronic blood loss usually produces iron-deficiency anemia.
Anemia due to excessive blood cell destruction: The specific hemolytic disorder should be treated.
Anemia due to decreased blood cell formation: For deficiency states, replacement therapy is used to combat the specific deficiency, e.g., iron, vitamin B12, folic acid, ascorbic acid. For bone marrow disorders, if anemia is due to a toxic state, removal of the toxic agent may result in spontaneous recovery.
Anemia due to renal failure, cancer chemotherapy, HIV, and other chronic diseases: Erythropoietin injections are helpful.
- PATIENT CARE
- The patient is evaluated for signs and symptoms, and the results of laboratory studies are reviewed for evidence of inadequate erythropoiesis or premature erythrocyte destruction. Prescribed diagnostic studies are scheduled and carried out. Rest: The patient is evaluated for fatigue; care and activities are planned and regular rest periods are scheduled. Mouth care: The patient's mouth is inspected daily for glossitis, mouth lesions, or ulcers. A sponge stick is recommended for oral care, and alkaline mouthwashes are suggested if mouth ulcers are present. A dental consultation may be required. Diet: The patient is encouraged to eat small portions at frequent intervals. Mouth care is provided before meals. The nurse or a nutritionist provides counseling based on type of anemia. Medications: Health care professionals teach the patient about medication actions, desired effects, adverse reactions, and correct dosing and administration. Patient education: The cause of the anemia and the rationale for prescribed treatment are explained to the patient and family. Teaching should cover the prescribed rest and activity regimen, diet, prevention of infection, including the need for frequent temperature checks, and the continuing need for periodic blood testing and medical evaluation.