Key Poinst Ch 30

Lewis: Medical-Surgical Nursing, 10th Edition Chapter 30 Hematologic Problems KEY POINTS ANEMIA Anemia is a deficiency in the number of erythrocytes (red blood cells [RBCs]), the quantity of hemoglobin, and/or the volume of packed RBCs (hematocrit). Anemia is not a specific disease; it is a manifestation of a number of pathologic processes. The various types of anemia can be grouped according to either a morphologic (cellular characteristic) or an etiologic (underlying cause) classification. The clinical manifestations of anemia are caused by the body’s response to tissue hypoxia. Hemoglobin (Hgb) levels are often used to determine the severity of anemia. Interventions may include blood or blood product transfusions, drug therapy, volume replacement, oxygen therapy, dietary modifications, and lifestyle changes. Correcting the cause of the anemia is ultimately the goal of therapy. ANEMIA CAUSED BY DECREASED ERTHYROCYTE PRODUCTION Iron-Deficiency Anemia Iron-deficiency anemia may develop from inadequate dietary intake, malabsorption, blood loss, or hemolysis. Also, pregnancy contributes to iron deficiency because of the diversion of iron to the fetus for erythropoiesis, blood loss at delivery, and lactation. The main goal of interprofessional care of iron-deficiency anemia is to treat the underlying disease that is causing reduced intake (e.g., malnutrition, alcoholism) or absorption of iron. It is important to recognize groups of individuals who are at an increased risk for the development of iron-deficiency anemia. Diet teaching, with an emphasis on foods high in iron and how to maximize absorption, is important for these patients. Thalassemia Thalassemia is a group of diseases that have an autosomal recessive genetic basis involving inadequate production of normal Hgb. An individual with thalassemia may have a heterozygous or homozygous form of the disease, based on the number of thalassemic genes that the individual has. Thalassemia minor requires no treatment because the body adapts to the reduction of Hgb. The symptoms of thalassemia major are managed with blood transfusions or exchange transfusions in conjunction with IV deferoxamine to reduce the iron overloading (hemochromatosis) that occurs with chronic transfusion therapy. Megaloblastic Anemias Megaloblastic anemias are a group of disorders caused by impaired deoxyribonucleic acid (DNA) synthesis and characterized by the presence of large RBCs. Macrocytic (large) RBCs are easily destroyed because they have fragile cell membranes. Two common forms of megaloblastic anemia are cobalamin deficiency and folic acid deficiency. Cobalamin (vitamin B12) deficiency is most commonly caused by pernicious anemia, which results in poor cobalamin absorption through the gastrointestinal (GI) tract. Parenteral or intranasal administration of cobalamin is the treatment of choice. No secretion of IF or no absorbtion of IF Folic acid (folate) deficiency can lead to megaloblastic anemia. Folic acid (folate) is required for DNA synthesis leading to RBC formation and maturation. Folic acid deficiency is treated by replacement therapy. Anemia of Chronic Disease Chronic inflammatory, autoimmune, infectious, or malignant diseases can lead to an underproduction of RBCs and mild shortening of RBC survival. The best treatment of anemia of chronic disease is correction of the underlying disorder. Aplastic Anemia Aplastic anemia is a disease in which the patient has peripheral blood pancytopenia (decrease of all blood cell types) and hypocellular bone marrow. Aplastic anemia, which are usually acquired, are idiopathic and thought to have an autoimmune basis. Management of aplastic anemia is based on identifying and removing the causative agent (when possible) and providing supportive care until the pancytopenia reverses. Immune therapies and bone marrow transplantation can be curative. ANEMIA CAUSED BY BLOOD LOSS Acute Blood Loss Acute blood loss occurs as a result of sudden hemorrhage (e.g., trauma, complications of surgery, and conditions or diseases that disrupt vascular integrity). Interprofessional care is initially concerned with replacing blood volume to prevent shock and identifying the source of the hemorrhage and stopping the blood loss. Chronic Blood Loss The sources of chronic blood loss are similar to those of iron-deficiency anemia (e.g., bleeding ulcer, hemorrhoids, menstrual and postmenopausal blood loss). Management of chronic blood loss anemia involves identifying the source and stopping the bleeding. Supplemental iron may be required. ANEMIA CAUSED BY INCREASED ERYTHROCYTE DESTRUCTION Sickle Cell Disease Sickle cell disease is a group of inherited, autosomal recessive disorders characterized by the presence of an abnormal form of Hgb in the erythrocyte. The major pathophysiologic event of this disease is the sickling of RBCs. Sickling episodes are most commonly triggered by low oxygen tension in the blood. With repeated episodes of sickling, there is gradual involvement of all body systems, especially the spleen, lungs, kidneys, and brain. Interprofessional care for a patient with sickle cell disease is directed toward alleviating the symptoms from the complications of the disease and minimizing end target-organ damage. Acquired Hemolytic Anemia Extrinsic causes of hemolysis can be separated into three categories: (1) physical trauma, (2) antibodies (immune reactions), and (3) infectious agents and toxins. Physical destruction of RBCs results from the exertion of extreme force on the cells such as when they travel past prosthetic heart valves, through partially occluded vessels in TTP. Antibodies may destroy RBCs by the mechanisms involved in antigen-antibody reactions. Infectious agents foster hemolysis in four ways: (1) by invading the RBC and destroying its contents, (2) by releasing hemolytic substances, (3) by generating an antigen-antibody reaction, and (4) by contributing to splenomegaly as a means of increasing removal of damaged RBCs from the circulation. Hemochromatosis Hemochromatosis is an autosomal recessive disease characterized by increased intestinal iron absorption and, as a result, increased tissue iron deposition. The goal of treatment is to remove excess iron from the body and minimize any symptoms the patient may have. Polycythemia Polycythemia is the production and presence of increased numbers of RBCs. The increase in RBCs can be so great that blood circulation is impaired as a result of the increased blood viscosity and volume. Treatment is directed toward reducing blood volume/viscosity and bone marrow activity. Phlebotomy is the mainstay of treatment. PROBLEMS OF HEMOSTASIS Thrombocytopenia Thrombocytopenia is a reduction of platelets below 150,000/?L (150 × 109/L). Platelet disorders can be inherited, but the vast majority are acquired. The causes of acquired disorders include autoimmune diseases, increased platelet consumption, splenomegaly, marrow suppression, and bone marrow failure. The most common acquired thrombocytopenia is a syndrome of abnormal destruction and reduced production of circulating platelets termed immune thrombocytopenic purpura (ITP). Multiple therapies are used to manage the patient with ITP, such as corticosteroids, splenectomy, immunosuppressants, or thrombopoietin receptor agonists. One of the risks associated with the broad and increasing use of heparin is the development of the life-threatening condition called heparin-induced thrombocytopenia (HIT). Heparin must be discontinued when HIT is first recognized, which is usually if the patient’s platelet count has fallen 50% or more from its baseline or if a thrombus forms while the patient is on heparin therapy. The overall goals are that the patient with thrombocytopenia will (1) have no gross or occult bleeding, (2) maintain vascular integrity, and (3) manage home care to prevent any complications related to an increased risk for bleeding. Hemophilia and von Willebrand Disease Hemophilia is a sex-linked recessive genetic disorder caused by defective or deficient coagulation factor. The two major forms of hemophilia, which can occur in mild to severe forms, are hemophilia A and hemophilia B. von Willebrand disease is a related disorder involving a deficiency of the von Willebrand coagulation protein. Replacement of deficient clotting factors is the primary means of supporting a patient with hemophilia. In addition to treating acute crises, replacement therapy may be given before surgery and dental care as a prophylactic measure. The patient with hemophilia is usually managed in the home setting with careful teaching to recognize disease-related problems and learn which problems can be resolved at home and which require hospitalization. Disseminated Intravascular Coagulation Disseminated intravascular coagulation (DIC) is a serious bleeding and thrombotic disorder. It results from abnormally initiated and accelerated clotting. The subsequent consumption leads to decreases in circulating and available clotting factors and platelets, which may lead to uncontrollable hemorrhage. DIC is always caused by an underlying disease or condition. The underlying problem must be treated for the DIC to resolve. It is important to diagnose DIC quickly, stabilize the patient if needed (e.g., oxygenation, volume replacement), institute therapy that will resolve the underlying causative disease or problem, and provide supportive care for the manifestations resulting from the pathology of DIC itself. Neutropenia Neutropenia is a reduction in neutrophils, a type of granulocyte, and therefore is sometime referred to as granulocytopenia. Neutrophils are closely monitored as an indicator of a patient’s risk for infection. Neutropenia is a clinical consequence that occurs with a variety of conditions or diseases. It can also be an expected effect, a side effect, or an unintentional effect of taking certain medications. Occasionally the cause of the neutropenia can be easily treated (e.g., nutritional deficiencies). However, neutropenia can also be a side effect that must be tolerated as a necessary step in therapy (e.g., chemotherapy, radiation therapy). In some situations the neutropenia resolves when the primary disease is treated. Monitor the neutropenic patient for signs and symptoms of infection and early septic shock. Prompt initiation of antimicrobial therapy is a priority of care. Myelodysplastic Syndrome Myelodysplastic syndrome (MDS) is a group of related hematologic disorders characterized by a change in the quantity and quality of bone marrow elements. Although it can occur in all age groups, the highest prevalence is in men over 80 years of age. Supportive treatment consists of hematologic monitoring, antibiotic therapy, or transfusions with blood products. The overall goal is to improve hematopoiesis and ensure age-related quality of life. Leukemia Leukemia is the general term used to describe a group of malignant disorders affecting the blood and blood-forming tissues of the bone marrow, lymph system, and spleen. Classification of leukemia can be done based on acute versus chronic and on the type of WBC involved, whether it is of myelogenous origin or of lymphocytic origin. The onset of acute myelogenous leukemia (AML) is often abrupt and dramatic. AML is characterized by uncontrolled proliferation of myeloblasts, the precursors of granulocytes. Acute lymphocytic leukemia (ALL) is the most common type of leukemia in children. Acute myelocytic leukemia (AML) accounts for about 80% of the acute leukemias in adults. Its onset is often abrupt and dramatic. A patient may have serious infections and abnormal bleeding from the onset of the disease. Chronic myelogenous leukemia (CML) is caused by excessive development of mature neoplastic granulocytes in the bone marrow, which move into the peripheral blood in massive numbers and ultimately infiltrate the liver and spleen. The natural history of CML is a chronic stable phase, followed by the development of a more acute, aggressive phase referred to as the blastic phase. Chronic lymphocytic leukemia (CLL) is characterized by the production and accumulation of functionally inactive but long-lived, small, mature-appearing lymphocytes. The lymphocytes infiltrate the bone marrow, spleen, and liver, and lymph node enlargement is present throughout the body. Once a diagnosis of leukemia has been made, interprofessional care is focused on the initial goal of attaining remission. In some cases, such as asymptomatic patients with CLL, watchful waiting with active supportive care may be appropriate. Chemotherapy is the mainstay of the treatment for leukemia. Hematopoietic stem cell transplantation may be used. The overall nursing goals are that the patient with leukemia will (1) understand and adhere to the treatment plan; (2) experience minimal side effects and complications associated with both the disease and its treatment; and (3) establish realistic hope and goals, feeling supported during the periods of treatment, relapse, or remission. Lymphomas Lymphomas are malignant neoplasms originating in the bone marrow and lymphatic structures resulting in the proliferation of lymphocytes. There are two major types of lymphoma: Hodgkin’s lymphoma and non-Hodgkin’s lymphoma (NHL). Hodgkin’s Lymphoma Hodgkin’s lymphoma, also called Hodgkin’s disease, is a malignant condition characterized by proliferation of abnormal giant, multinucleated cells, called Reed-Sternberg cells, which are located in lymph nodes. Although the cause of Hodgkin’s lymphoma remains unknown, the main interacting factors include infection with Epstein-Barr virus, genetic predisposition, and exposure to occupational toxins. The incidence of Hodgkin’s lymphoma is increased among patients with human immunodeficiency virus. The nursing care for Hodgkin’s lymphoma is largely based on managing problems related to the disease (e.g., pain caused by tumor), pancytopenia, and other side effects of therapy. Non-Hodgkin’s Lymphomas Non-Hodgkin’s lymphomas (NHLs) are a heterogeneous group of malignant neoplasms of primarily B-, T-, or NK-cell origin, affecting all ages. A variety of clinical presentations and courses are recognized from indolent (slowly developing) to rapidly progressive disease. NHLs can originate outside the lymph nodes, the method of spreading can be unpredictable, and the majority of patients have widely disseminated disease at the time of diagnosis. Treatment for NHL involves chemotherapy and sometimes radiation therapy. Nursing care is largely based on managing problems related to the disease (e.g., pain caused by the tumor, spinal cord compression, tumor lysis syndrome), pancytopenia, and other side effects of therapy. Multiple Myeloma Multiple myeloma, or plasma cell myeloma, is a condition in which neoplastic plasma cells infiltrate the bone marrow and destroy bone. Multiple myeloma develops slowly and insidiously. The patient often does not manifest symptoms until the disease is advanced. Multiple myeloma is rarely cured, but treatment can relieve symptoms, produce remission, and prolong life. Chemotherapy is usually the first treatment recommended for multiple myeloma. Maintaining adequate hydration is a primary nursing consideration to minimize problems from hypercalcemia and potential renal failure. Because of the potential for pathologic fractures, care must be taken when moving and ambulating the patient. Disorders of the Spleen The spleen can be affected by many illnesses, which can cause varying degrees of splenomegaly (enlargement of the spleen). With splenomegaly, there is an increased filtering and sequestering capacity, lowering the number of circulating blood cells. Splenomegaly is generally well tolerated. There may be complaints of abdominal pain and early satiety. An enlarged spleen is easily palpable on physical examination. A splenectomy may be indicated for the evaluation or treatment of splenomegaly. It may also be performed if the spleen ruptures from trauma. BLOOD COMPONENT THERAPY Blood component therapy is frequently used in managing hematologic diseases. However, blood component therapy only temporarily supports the patient until the underlying problem is resolved. When the blood or blood components have been obtained from the blood bank, positive identification of the donor blood and recipient must be made. Improper product-to-patient identification causes most hemolytic transfusion reactions. The blood should be administered as soon as it is brought to the patient. It should not be refrigerated on the nursing unit. Autotransfusion, or autologous transfusion, consists of removing whole blood from a person and transfusing that blood back into the same person. The problems of incompatibility, allergic reactions, and transmission of disease can be avoided. A blood transfusion reaction is an adverse reaction to blood transfusion therapy that can range in severity from mild symptoms to a life-threatening condition. Blood transfusion reactions can be classified as acute or delayed. Acute Transfusion Reactions The most common cause of hemolytic reactions is transfusion of ABO-incompatible blood. Febrile reactions are most commonly caused by leukocyte incompatibility. Many individuals who receive five or more transfusions develop circulating antibodies to the small amount of WBCs in the blood product. Allergic reactions result from the recipient’s sensitivity to plasma proteins of the donor’s blood. These reactions are more common in an individual with a history of allergies. An individual with cardiac or renal insufficiency is at risk for developing circulatory overload. This is especially true if a large quantity of blood is infused in a short period, particularly in an older patient. Transfusion-related acute lung injury (TRALI) is characterized by the sudden development of noncardiogenic pulmonary edema (acute lung injury). An acute complication of transfusing large volumes of blood products is termed massive blood transfusion reaction. Massive blood transfusion reactions can occur when replacement of 10 or more units of RBCs are transfused within 24 hours. Delayed Transfusion Reactions Delayed transfusion reactions include delayed hemolytic reactions, infections, and iron overload. Infectious agents transmitted by blood transfusion include hepatitis B and C viruses, human immunodeficiency virus, human herpesvirus type 6, Epstein-Barr virus, human T-cell leukemia virus, type 1 (HTLV-1), cytomegalovirus, and malaria.