Interventions for Clients with Hematologic Problems

1. Interventions for Clients with Hematologic Problems RED BLOOD CELL DISORDERS

2. Disorders of the hematologic system can occur as a result of problems in the production, function, or normal destruction of any type of blood cell. • The type and severity of the specific disorder determine the degree of threat to the client's well-being

3. RED BLOOD CELL DISORDERS • The major cellular population of the blood consists of red blood cells (RBCs), or erythrocytes. • Adequate tissue oxygenation depends on maintaining the circulating number of RBCs within the normal range for the person's age and gender and ensuring that the cells can perform their normal functions. RBC disorders include problems in production, function, anddestruction. • These problems may result in an insufficient number or insufficient function of RBCs (anemia) or an excess of RBCs (polycythemia).

4. RED BLOOD CELL DISORDERS • Anemia is a reduction in either the number of RBCs, the quantity of hemoglobin, or the hematocrit (percentage of packed RBCs per deciliter of blood). • Anemia is a clinical sign, not a diagnosis, because it is a manifestation of a number of abnormal conditions. • Despite the many causes of anemia, the effects of anemia on the client and the corresponding nursing care are similar for all types of anemia

7. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • Sickle cell disease is a condition in which chronic anemia is one of many problems causing pain, disability, increased risk for disease, and early death. • Once considered a childhood disorder, clients with sickle cell disease who receive appropriate supportive care may live into their 30s and 40s. • In addition, there is great variation among clients in the severity of the disease and the onset of complications.

8. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Pathophysiology • Hereditary disorder - formation of abnormal beta chains in the hemoglobin molecule. • Thenormal hemoglobin molecule of adults is composed partially of the globin protein, consisting of two alpha chains and two beta chains of amino acids (hemoglobin A (HbA)). The total hemoglobin of normal healthy adults is usually 98% to 99% HbA, with a small percentage of a fetal form of hemoglobin (HbF). • In sickle cell disease, at least 40% of the total hemoglobin contains an abnormality of the beta chains, known as hemoglobin S (HbS).

9. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • HbS is sensitive to changes in the oxygen content of the RBC. When RBCs containing large amounts of HbS are exposed to conditions of decreased oxygen, the abnormal beta chains contract and pile together within the cell, distorting the overall shape of the RBC. • These cells assume a sickle shape, become rigid, clump together, and form clusters that block capillary blood flow. • Capillary obstruction leads to further tissue hypoxia (reduced oxygen supply) and more sickling, causing blood vessel obstructions and infarctions in the locally affected tissues. • Situations that lead to sickling include hypoxia, dehydration, infections, vascular stasis, low environmental or body temperatures, acidosis, strenuous exercise, and anesthesia

10. Red blood cell actions under conditions of low tissue oxygenation. (HbS, Hemoglobin S; HbA, hemoglobin A.)

11. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • Usually, sickled cells resume a normal shape when the precipitating condition is removed and proper oxygenation occurs. • The membranes of the cells become damaged over time, and cells become irreversibly sickled. • The membranes of cells with HbS are more fragile and more easily destroyed in the spleen and in other organs that have long, twisted capillary pathways. The average life span of an RBC containing 40% or more of HbS is approximately 20 days. This reduced life span is responsible for hemolytic (blood cell-destroying) anemia in clients with sickle cell disease.

12. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • The client with sickle cell disease experiences periodic episodes of extensive cellular sickling, or crises. • Repeated occlusions of progressively larger blood vessels have long-term negative effects on tissues and organs. Most effects are thought to occur as a result of capillary and blood vessel occlusion leading to tissue hypoxia, anoxia, ischemia, and cell death. • Tissues and organs begin tohave small infarcted areas that eventually destroy all healthy cells and lead to organ failure. • Tissues and organs most commonly affected in this way are the spleen, liver, heart, kidney, brain, bones, and retina

13. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Etiology • Sickle cell disease is a genetic disorder with an autosomal recessive pattern of inheritance. • The formation of the beta chains of the hemoglobin molecule is dependent on a pair of genes. • When the client inherits one abnormal gene of this pair, the condition is called sickle cell trait. • When the client inherits two abnormal genes, the condition is called sickle cell disease (formerly sickle cell anemia), and the client has severe manifestations of the disease even under relatively mild precipitating conditions. In addition, if the client has children, each child will inherit one of the two abnormal genes and at least have sickle cell trait

14. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Cultural considerations • Sickle cell disease occurs most often in African Americans, as well as in African, Mediterranean, Caribbean, Middle Eastern, and Central American populations. • Approximately 1 of every 12 African Americans has the sickle cell trait. • One of every 345 African-American infants inherits two abnormal genes (one from each parent) and has overt sickle cell disease

15. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease History • An adult with sickle cell disease has a long-standing diagnosis of the disorder. • The nurse asks the client about previous crises, including precipitating events, severity, and usual treatments. • Recent ac­tivities and situations are explored to determine the probable precipitating condition or event. • The nurse also reviews all activities and events during the previous 24 hours, including food and fluid intake, exposure to temperature extremes, types of clothing worn, medications taken, exercise, trauma, stress, and ingestion of alcohol or other recreational drugs. This activity review provides important information about fatigue, activity tolerance, and participation in activities of daily living (ADLs).

16. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • The client is asked about changes in sleep and rest patterns, ability to climb stairs, and any activity that induces shortness of breath. • Obtaining a subjective baseline assessment of the client's perceived energy level using a scale ranging from 0 to 10 (0 = not tired with plenty of energy; 10 = total exhaustion) can be useful in evaluating the degree of fatigue and the effectiveness of later treatments

17. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Physical assessment/clinical manifestations • Pain is the most common symptom experienced during sickle cell crisis. • Jaundice may also be present as a result of increased red blood cell (RBC) destruction and release of bilirubin. • Other clinical manifestations vary with the site of tissue damage. Cardiovascular assessment • Compare peripheral pulses, temperature, and capillary refill in all extremities • Extremities distal to blood vessel occlusion are cool to the touch with slow capillary refill and may have diminished or absent pulses. • The heart rate may be rapid and the blood pressure low to average, with a decreased pulse pressure because breakage of RBCs leads to anemia

18. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Integumentary assessment • The skin may be pale or cyanotic as a result of decreased perfusion and anemia. The nurse examines the lips, tongue, nail beds, conjunctivae, palms, and soles at regular intervals for subtle color changes. With cyanosis, the lips and tongue are gray, and the palms, soles, conjunctivae, and nail beds have a bluish tinge. • Jaundice. The nurse assesses for jaundice in clients with darker skin by inspecting the oral mucosa, especially the hard palate, for yellow discoloration. Inspection of the conjunctivae and adjacent sclera may be misleading because of normal deposits of subconjunctival fat that produce a yellowish hue when seen in contrast to the dark periorbital skin. Therefore the nurse examines the sclera closest to the cornea to diagnose jaundice more accurately. Jaundice from excessive bilirubin may also cause intense itching.

19. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Abdominal assessment • Abdominal organs are usually the first to be damaged as a result of multiple episodes of hypoxia and ischemia. The nurse inspects the abdomen for asymmetry or bulging areas, gently palpating it. Affected organs, such as the liver or spleen, may be firm and enlarged with a nodular texture in later stages of the disease Musculoskeletal assessment • Extremities are a common site of vascular occlusion among clients who have sickle cell disease. In addition, joints may be damaged from frequent hypoxic episodes and undergo necrotic degeneration. • The nurse inspects the extremities for symmetry and records any areas of swelling or color difference. Clients are asked to move all joints, and the nurse notes the range of motion and any accompanying pain

20. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Central nervous system assessment • During crises, clients may have a low-grade fever. If the CNS sustains infarcts or repeated episodes of hypoxia, they may have seizure activity or clinical manifestations of a stroke. Hand grasps are assessed bilaterally. The nurse assesses gait and coordination in those clients who are permitted to walk. Laboratory assessment • Large percentage of hemoglobin S (HbS) present on electrophoresis. A person who has sickle cell trait usually expresses less than 40% HbS, and the client with sickle cell disease may express 85% to 95% HbS. This percentage does not change during crises. • Another indicator of sickle cell disease is the percentage of RBCs showing irreversible sickling. This value is less than 1% among people who do not have sickle cell disease, is 5% to 50% among people with sickle cell trait, and may exceed 90% among clients with sickle cell disease

21. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • The hematocrit of clients with sickle cell disease is usually low (between 20% and 30%). This value decreases even more dramatically during vascular occlusive crises, or aplastic crises, when the bone marrow temporarily fails to produce cells during stressful periods (such as infection). • The reticulocyte count is elevated, indicating anemia of long duration. Often the mean corpuscular hemoglobin concentration (MCHC) and total bilirubin level are elevated in the client who has sickle cell disease. • The total white blood cell (WBC) count is usually above normal among clients who have sickle cell disease. It is thought that this elevation is related to chronic inflammation resulting from tissue hypoxia and ischemia

22. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Radiographic assessment • Bone changes occur as a result of chronically stimulated marrow and hypoxic bone tissue. The skull may show radiographic changes resulting from chronic bone surface resorption and regeneration, giving the skull a "crew cut" appearance. Joint necrosis and degeneration also are obvious on x-ray examination. Other diagnostic assessment • Electrocardiographic (ECG) changes document cardiac infarcts and tissue damage. • Ultra-sonography, computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI) may reveal soft-tissue and organ degenerative changes resulting from inadequate oxygenation and chronic inflammation

25. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease Interventions • PAIN DRUG THERAPY. Clients in acute sickle cell crisis often require at least 48 hours of parenteral analgesics. • Morphine and hydromorphone (Dilaudid) are the medications of choice • For sickle cell crisis, these agents should be administered intravenously on a routine schedule. Once relief is obtained, the intravenous (IV) dose can be tapered and then administered orally • Meperidine (Demerol) is also used for sickle cell crisis, but long-term use of this agent can cause neurologic symptoms, including anxiety and seizures • Intramuscular (IM) injections are avoidedbecause frequent injections lead to sclerosing of tissue (and absorption may be impaired by poor circulation). • Moderate pain may be treated with oral doses of codeine, morphine sulfate, or nonsteroidal antiinflammatory drugs (NSAIDs)

26. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • Complementary therapies and other nonpharmacologic measures, such as keeping the room warm, using distraction and relaxation techniques, proper positioning with support for painful areas, aroma therapy, therapeutic touch, and warm soaks or compresses, have all been useful in decreasing pain. • The nurse must not assume, however, that these methods alone will provide adequate pain relief. Analgesics are required to treat sickle cell pain

27. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • POTENTIAL FOR SEPSIS. The client with sickle cell disease is more susceptible to bloodborne infections and infection by encapsulated microorganisms, such as Streptococcus pneumoniae and Haemophilus influenzae, as a result of decreased spleen function. Interventions aim at preventing or halting the process of infection, controlling infection, and initiating early, effective treatment regimens for specific infections. • PREVENTION/EARLY DETECTION.Frequent, thorough handwashing is of the utmost importance. Any person with an upper respiratory tract infection who must enter the client's room wears a mask. Strict aseptic technique is used for all invasive procedures. • The nurse continually assesses the client for the presence of infection and monitors a daily complete blood count (CBC) with differential WBC count. The oral mucosa is inspected during every nursing shift for lesions indicating fungal or viral infection. The lungs are auscultated every 8 hours for crackles, wheezes, or diminished breath sounds. Each time the client voids, assistive nursing personnel inspect the urine for odor and cloudiness, and the client is asked about any sen­sation of urgency, burning, or pain during urination. Vital signs are taken at least every 4 hours to assess for fever

28. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • DRUG THERAPY.Prophylactic therapy with twice-daily administration of oral penicillin in the penicillin-tolerant client has resulted in dramatic reductions in the number of pneumonia and other streptococcal infections. Agents used depend on the sensitivity of the specific organism causing the infection, as well as the extent of the infection

29. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSSickle Cell Disease • POTENTIAL FOR MULTIPLE ORGAN DYSFUNCTION • The client in sickle cell crisis is admitted to the acute care hospital. The nurse assesses for adequacy of circulation to all body areas. Restrictive clothing is removed, and the client is in­structed to avoid keeping the hips or knees in a flexed position. • Dehydration perpetuates cell sickling and must be avoided. Nursing personnel assist the client in maintaining an adequate hydration status. The client in crisis requires an oral or parenteral intake of at least 200 mL/hr. • Oxygen is ordered, and the nurse ensures that oxygen therapy is delivered appropriately, including nebulization to prevent dehydration. • Transfusion therapy has been used to decrease the incidence of organ dysfunction and stroke. RBC transfusions are therapeutic because levels of hemoglobin A (HbA) are sustained, whereas levels of hemoglobin S (HbS) are diluted. Transfusions also suppress erythropoiesis, thereby decreasing the production of sickle cells. Transfusions may be administered in either the acute care or clinic setting by a registered nurse. The nurse monitors the client closely for complications of transfusion therapy • In some treatment centers, bone marrow transplantation is being performed to correct abnormal hemoglobin permanently. Because bone marrow transplantation is expensive and may result in chronic and life-threatening complications, its risks and benefits need to be seriously considered for each client

30. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSGlucose-6-Phosphate Dehydrogenase Deficiency Anemia Overview • Many forms of congenital hemolytic (blood cell-destroying) anemia result from defects or deficiencies of one or more enzymes within the red blood cell (RBC). More than 200 such disorders have been identified. Most of these enzymes are needed to complete some critical step in cellular energy production. The most common type of congenital hemolytic anemia is associated with a deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD). This disease is inherited as an X-linked recessive disorder and affects about 10% of all African Americans. • G6PD stimulates critical reactions in the glycolytic pathway. RBCs contain no mitochondria, so active glycolysis is essential for energy metabolism. Newly produced RBCs from clients with G6PD deficiency have relatively sufficient quantities of G6PD; however, as the cells age, the concentration diminishes drastically. Cells that have reduced amounts of G6PD are more susceptible to breaking during exposure to specific drugs (e.g., phenacetin, sulfonamides, aspirin [acetylsalicylic acid], quinine derivatives, thiazide diuretics, and vitamin K derivatives) and toxins. • After exposure to any of these agents, clients experience acute intravascular hemolysis lasting from 7 to 12 days. During this acute phase, anemia and jaundice develop. The hemolytic reaction is self-limited because only older erythrocytes, containing less G6PD, are destroyed

31. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSGlucose-6-Phosphate Dehydrogenase Deficiency Anemia Collaborative management • It is critical that the precipitating drug or the agent responsible for the hemolytic reaction be identified and totally removed. People should be screened for this deficiency before donating blood, because administration of cells deficient in G6PD can be hazardous for the recipient. • During and immediately after an episode of hemolysis, adequate hydration is essential to prevent precipitation of cellular debris and hemoglobin in the kidney tubules, which can lead to acute tubular necrosis. Osmotic diuretics, such as mannitol (Osmitrol), may assist in preventing this complication. Transfusion therapy is indicated when anemia is present and kidney function is normal

32. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSImmunohemolytic Anemia Overview • Increased RBC destruction through hemolysis can occur in response to many situations, including trauma, infection (especially malarial infections), and autoimmune reactions. All increase the rate at which RBCs are destroyed by causing lysis (breakage) of the RBC membrane. • In immunohemolytic anemia, immune system components attack a person's own RBCs. The exact mechanism that causes immune components to no longer recognize blood cells as self and to initiate destructive processes against RBCs is not known. Some hemolytic anemias are present with other autoimmune disorders (such as systemic lupus erythematosus) or lymphoproliferative disorders. Regardless of the cause, RBCs are viewed as non-self by the immune system and are destroyed.

33. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSImmunohemolytic Anemia • There are two types of immunohemolytic anemia: warm antibody anemia and cold antibody anemia. • Warm antibody anemia is usually associated with immunoglobulin G (IgG) antibody excess. These antibodies are most active at 98° F (37° C) and may be stimulated by drugs, chemicals, or other autoimmune problems. • Cold antibody anemia is associated with fixation of complement proteins on immunoglobulin M(IgM) and occurs best at 86° F (30° C). This problem is commonly associated with a Raynaud-like response in which the arteries in the distal extremities constrict profoundly in response to cold temperatures or stress

34. ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLSImmunohemolytic Anemia Collaborative management • Treatment depends on clinical severity. Steroid therapy for mild to moderate immunosuppression is the first line of treatment and is temporarily effective in most clients. Splenectomy and more intensive immunosuppressive therapy with cyclophosphamide (Cytoxan, Procytox) and azathioprine (Imuran) may be instituted if steroid therapy fails. Plasma exchange therapy to remove attacking antibodies is effective for clients who do not respond to immunosuppressive therapy

35. Indications for treatment with blood components

36. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSIron Deficiency Anemia Overview • The adult body contains between 2 and 6 g of iron, depending on the size of the person and the amount of hemoglobin in the cells. • Approximately two thirds of this iron is contained in hemoglobin; the other third is stored in the bone marrow, spleen, liver, and muscle. • If a person has an iron deficiency, the iron stores are depleted first, followed by the hemoglobin stores. As a result, RBCs are small (microcytic), and the client has relatively mild manifestations of anemia, including weakness and pallor. In iron deficiency anemia, serum ferritin values are less than 12 g/L. • Iron deficiency anemia is the most common type of anemia and can result from blood loss, increased energy demands, gastrointestinal malabsorption, and dietary inadequacy. • The basic problem of iron deficiency anemia is a decreased supply of iron for the developing RBC. Iron deficiency anemia can occur at any age but is more frequent in women, older adults, and people with poor diets

37. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSIron Deficiency Anemia Collaborative management • The primary treatment of clients with iron deficiency anemia is to increase the oral intake of iron from common food sources. • An adequate diet supplies a person with about 10 to 15 mg of iron per day, of which only 5% to 10% is absorbed in the stomach, duodenum, and upper jejunum. This amount is sufficient to meet the needs of healthy men and healthy women after childbearing age but is not sufficient to supply the greater needs of menstruating women and adolescents during growth spurts. • Fortunately, if iron intake is inadequate, or if bleeding or pregnancy occurs, the gastrointestinal tract is capable of increasing the absorption of iron to about 20% to 30% of the total daily intake. • When iron deficiency anemia is severe, iron preparations can be administered intramuscularly. Such preparations are administered using the Z-track best practice method

38. Common food sources of iron, vitamin b12, and folic acid

39. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSVitamin B12 Deficiency Anemia Overview • Proper production of RBCs depends on adequate desoxyribonucleic acid (DNA) synthesis in the precursor cells so that cell division and maturation into functional RBCs can occur. • All DNA synthesis requires adequate amounts of folik acid to ensure the availability of the nucleotide thymidine,which stimulates DNA synthesis. One function of vitamin B12 is to serve as a cofactor to activate the enzyme system responsible for transporting folic acid into the cell, where DNA synthesis occurs. • Thus a deficiency of vitamin B12 indirectly causes anemia by inhibiting folic acid transportation and limiting DNA synthesis in RBC precursor cells. • These precursor cells then undergo improper DNA synthesis and increase in size. Only a few are released from the bone marrow. This type of anemia is called megaloblastic (macrocytic) because of the large size of these abnormal cells.

40. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSVitamin B12 Deficiency Anemia • Vitamin B12 deficiency can result from inadequate intake (dietary deficiency). This can occur with strict vegetarian diets or diets lacking sufficient dairy products. • Conditions such as small bowel resection, diverticula, tapeworm, or overgrowth of intestinal bacteria can lead to poor absorption of vitamin B12 from the intestinal tract. • Anemia caused by failure to absorb vitamin B12(pernicious anemia) can also result from a deficiency of intrinsic factor (a substance normally secreted by the gastric mucosa), which is necessary for intestinal absorption of vitamin B12. • Vitamin B12deficiency anemia may be mild or severe, usually develops slowly, and produces few symptoms. Clients usually have pallor and jaundice, as well as glossitis (a smooth, beefy-red tongue), fatigue, and weight loss. • Because vitamin B12 also is necessary for normal nervous system functioning, especially of the peripheral nerves, clients with pernicious anemia may also have neurologic abnormalities, such as paresthesias (abnormal sensations) in the feet and hands and disturbances of balance and gait.

41. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSVitamin B12 Deficiency Anemia Collaborative management • When anemia is caused by a dietary deficiency, the client must increase the intake of foods rich in vitamin B12 (animal proteins, eggs, dairy products). • Vitamin supplements may be prescribed when anemia is severe. For clients who have anemia asa result of a deficiency of intrinsic factor, vitamin B12 must be administered parenterally on a regular schedule (usually weekly for initial treatment, then monthly for maintenance).

42. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSFolic Acid Deficiency Anemia Overview • Primary folic acid deficiency can also cause megaloblastic anemia. Clinical manifestations are similar to those of vitamin B12 deficiency without the accompanying nervous system manifestations, because folic acid does not appear to affect nerve function. • The absence of neurologic problems is an important diagnostic finding to differentiate folic acid deficiency from vitamin B12 deficiency. The disease develops slowly, and symptoms may be attributed to other problems or diseases. • The three common causes of folic acid deficiency are poor nutrition, malabsorption, and drugs. Poor nutrition, especially a diet lacking green leafy vegetables, liver, yeast, citrus fruits, dried beans, and nuts, is the most common cause. Chronic alcohol abuse and parenteral alimentation without folic acid supplementation are other dietary causes. • Malabsorption syndromes, such as Crohn's disease, are the second most common cause. • Specific drugs impede the absorption and conversion of folic acid to its active form and can also lead to folic acid deficiency and anemia. Such drugs include methotrexate, some anticonvulsants, and oral contraceptives

43. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSFolic Acid Deficiency Anemia Collaborative management • Prevention of folic acid deficiency anemia is aimed at identifying high-risk clients, such as older, debilitated clients with alcoholism; clients prone to malnutrition; and those with increased folic acid requirements. • A diet high in folic acid and vitamin B12 prevents a deficiency. • By routinely including assessment of dietary habits in a health history, the nurse can determine which clients are at risk for diet-induced anemias and provide appropriate follow-up. • For the client diagnosed with this type of anemia, management includes oral folic acid 1 mg daily or intramuscular administration of folic acid for clients with absorption problems.

44. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSAplastic Anemia Overview • Aplastic anemia is a deficiency of circulating erythrocytes resulting from arrested development of RBCs within the bone marrow. It is caused by an injury to the hematopoietic precursor cell, the pluripotent stem cell. • Although aplastic anemiasometimes occurs alone, it is usually accompanied by agranulocytopenia (a reduction in leukocytes) and thrombocytopenia (a reduction in platelets). • These three problems occur at the same time because the bone marrow produces not only RBCs but also white blood cells (WBCs) and platelets. • Consequently, if the bone marrow is abnormal for any reason or if it has been exposed to a toxic substance that can damage bone marrow cells, production of erythrocytes, leukocytes, and thrombocytes slows greatly. Pancytopenia (a deficiency of all three cell types) is common in aplastic anemia.

45. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSAplastic Anemia • The onset of aplastic anemia may be insidious or rapid. • The development of aplastic anemia, although relatively rare, is associated with chronic exposure to several toxic agents. In about 50% of cases, the cause of aplastic anemia is unknown. Aplastic anemia may occur as an aftermath of viral infection, but the mechanism of bone marrow damage is unknown

46. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSAplastic Anemia Collaborative management • Blood transfusions are the mainstay of treatment for clients with aplastic anemia. • Transfusion is indicated only when the anemia causes real disability or when bleeding is life threatening because of thrombocytopenia. • Unnecessary transfusion, however, increases the opportunity for the development of immune reactions to platelets, shortens the life span of the transfused cell, and may increase the rate of rejection of trans­planted marrow cells. Thus transfusions are discontinued as soon as the bone marrow begins to produce RBCs.

47. ANEMIAS RESULTING FROM DECREASEDPRODUCTION OF RED BLOOD CELLSAplastic Anemia • Because clients with some types of aplastic anemia have a disease course similar to that of autoimmune problems, immunosuppressive therapy may be helpful. Agents that selectively suppress lymphocyte activity, such as antilymphocyte globulin (ALG), antithymocyte globulin (ATG), and cyclosporine (Sandimmune), have brought about partial or complete remissions. In more severe cases, general immunosuppressive agents, such as prednisone and cyclophosphamide (Cytoxan, Procytox), have been effective. • Splenectomy (removal of the spleen) is considered in clients with an enlarged spleen that is either destroying normal RBCs or suppressing their development. • Bone marrow trans­plantation, which replaces defective stem cells, has also resulted in a cure for some clients. Cost, availability, and complications limit this technique for treatment of aplastic anemia, however

48. POLYCYTHEMIA • In polycythemia, the number of red blood cells (RBCs) in whole blood is greater than normal. • The blood of a client with polycythemia is hyperviscous (thicker than normal blood). • The problem may be temporary (occurring as a result of other conditions) or chronic. One type of polycythemia, polycythemia vera, is fatal if left untreated.

49. Polycythemia Vera Overview • Polycythemia vera (PV) is characterized by a sustained increase in blood hemoglobin concentration to 18 g/dL, an RBC count of 6 million/mm3, or a hematocrit increase to 55% or greater. • PV is a cancer of the RBCs with three major hallmarks: continuous production of massive numbers of RBCs, excessive leukocyte production, and overproduction of thrombocytes. Extreme hypercellularity (cell excess) of the peripheral blood occurs in people with PV • The skin, especially facial, and mucous membranes have a dark, flushed (plethoric) appearance. These areas may appear purplish or cyanotic because the blood in these tissues is incompletely oxygenated. Most clients experience intense itching related to vasodilation and variation in tissue oxygenation.

50. Polycythemia Vera • Blood viscosity is also greatly increased, causing a corresponding increase in peripheral resistance. • Superficial veins are visibly distended. Blood moves more slowly through all tissues and thus places increased demands on the pumping action of the heart, resulting in hypertension. In some highly vascular areas, blood flow may become so slow that vascular stasis occurs. Vascular stasis causes thrombosis (clot formation) within the smaller vessels to the extent that the vessels are occluded and the surrounding tissues experience hypoxia, progressing to anoxia and further to infarction and necrosis. Tissues most prone to this complication are the heart, spleen, and kidneys, although infarction with loss of tissue and organ function can occur in any organ or tissue