4Hematologic SystemBone marrow contains the essential element in the hematologic system….The STEM CELL aka the pluripotential stem cell, meaning it has the ability to transform into more than one type of blood cell.Remember, every blood cell in the body arises from a stem cell.Although it’s fluid, blood is one of the body’s major tissues.
5Blood FormationIn utero, the process of blood formation, called hematopoiesis, occurs in the liver and spleen. These organs retain some hematopoietic ability throughout life.After birth, the red bone marrow becomes the main site of hematopoiesis.The stem cells contained in the red marrow create blast cells. These are precursors toRBCs, WBCs and PLTsIn infants and young children, all bones contain red bone marrow. And are therefore, capable of hematopoiesis. However, as the child approaches adolescence and bone growth stops, the bone marrow in many bones can’t form blood cells because the marrow has transformed to yellow bone marrow (fat deposits), although it can usually revert to red bone marrow during times of increased blood cell demand. Only the ribs, sternum, vertebra and pelvis continue to contain red bone marrow and produce blood cells.
6Blood Components Blood is composed on plasma and cells 90% water10% solutes, such as proteins, electrolytes, albumin, clotting factors, anticoagulants, antibodies and dissolved nutrients.3 main cell typesRBCs or erythrocytesWBC or leukocytesPlatelets, or thrombocytesSee Table 28-1 for normal pediatric values
7Red Blood Cells Carry O2 to the tissues, and CO2 away from tissues During times of hypoxia, a hormone from the kidneys (erythropoietin) stimulates the bone marrow to produce more RBCs.Synthetic forms now availableLife of RBC= 120 daysAn important waste product of RBC death is bilirubinBilirubin binds with albumin for transport to the liver cells to conjugate with glucuronide, forming direct bilirubin. Because unconjugated bili is fat-soluble and can’t be excreted in urine or bile, it may escape to extravascular tissue, especially fatty tissue and the brain, restulting in hyperbilirubinemiaO2 Is carried in the cell in a protein (globin) and iron (heme) structure known as hemoglobin. If adequate amounts of Iron aren’t available, the protein structure can’t be formed and RBCs cant carry their normal amount of oxygen.
8White Blood CellsFight different types of infection in our body; each type has it’s own role2 main categories of WBC’sGranular leukocytes (granulocytes)Neutrphils, decour invading microorganisms by phagocytosisEosinophils, act in allergic rxns, defend against parasites and lung and skin infectionsBasophils, release heparin and histamine, involved in inflammatory and infectious rxns, aka mast cells in body tissuesNongranular leukocytes (agranulocytes)Lymphocytes, which are the main cells that fight infections and include B and T cellsMonocytes, work with neutrophils to help devour invading organisms
10PlateletsAdhere to one another and plug holes in vessels or tissues where there’s bleeding.This action is part of a larger coagulation processPLTs also release serotonin at injury sitesSerotonin is a vasoconstrictor, decreases blood flow to injured areas
11Iron Deficiency Anemia A disorder of O2 transport in which the production of hgb is inadequate.Without sufficient iron, the body can’t produce the Hgb molecure, b/c the heme component is primarily iron
12Iron Deficiency Anemia The cause?Inadequate intake of iron in the diet, malabsorption of iron through the GI tract, or chronic blood lossLast trimester of pregnancy, the fetus draws what iron it needs for the next 6-12 monthsIf mother is deficient in iron orBaby is more than 4 weeks premature (32 weeks) may not have sufficient iron intakeAnemia will usually present in 2nd year of life
13Iron Deficiency Anemia Who knew? About 80% of iron used in building Hgb is actually reabsorbed in the GI tract from dead RBCs that have broken up.Therefore, problems w/ GI absorption causes iron deficiencyCow’s milk allergy (common in Blacks and Asians) causes inflammation of GI tractIn adolescents- fad diets
14Iron Deficiency Anemia Clinical Manifestations:Range from mild to severePale appearance and decreased activityToddlers may have h/o prematurity and poor weight gainOther sxs includeFatigue, inability to concentrate, palpitations, dyspnea on exertion, craving for nonnutritive substances such as ice, tachycardia, dry brittle nails, concave or “spoon-shaped fingernails
15Iron Deficiency Anemia lab values Tests: Hgb levels are routinely screened, and a CBC is typically done at 9-12 months and 24 month well-baby check-ups and at-risk populationsIron deficiency is a microcytic, hypochromic anemia, meaning the RBC’s are small and pale. RBCs w/ decreased iron appear bleached outB/c the cells are small, the Mean corpuscular volume (MCV), the Mean corpuscular hemoglobin (MCH) and the Mean corpuscular hemoglobin concentrations are low.Serum iron levels are decreased
16Iron deficiency anemia lab values HemoglobinHematocritReticulocyte count=Hemoglobin g/dL= Mild iron deficiencyHemoglobin g/dL= Moderate iron deficiency anemiaHemoglobin less than 8 g/dL= severe iron deficiency anemiaReticulocyte count= helps distinguish a hypoproductive anemia from a destructive processdecrease= indicates bone marrow disorders or aplastic crisisincrease= indicates hemolytic process or active blood loss
17Iron Deficiency Anemia So what is the greatest nutritional risk factor for developing iron deficiency anemia?Intro of cow’s milk in first year of life
18Iron Deficiency Anemia Complications Untreated, anemia can cause stress on all body tissues, w/ decreased oxygenation, especially respiratory and cardiovascular systemsDecreased ability to concentratePoor muscle developmentDecreased performance on developmental tests
19Iron Deficiency Anemia Treatment The AAP recommends if Hct less than 34% or Hgb less than 11.3 g/dL begin iron supplementationMain treatment:Treat underlying problemGI bleeding, chronic blood lossLack of iron from dietIron SupplementationORAL ferrous sulfate at 3-6 mg/kg/day for 4 weeks, then repeat Hgb/HctAdminister through a straw, nippleAdminister on empty stomachAdminister with source of vitamin CSES of iron administration include-black tarry stoolsConstipationGI discomfortFoul aftertaste
20Iron Deficiency Anemia Iron Rich FoodsIron fortified cereal and formulaEnriched breadDark green vegetablesLegumes (kidney and pinto beans)Figs, raisinsMeats, fish, poultryDried appricots
21Iron Deficiency Anemia Evaluation With tx, reticulocyte count increases w/in 3-5 days. Indicates + therapeutic responseHgb should normalize w/in 4-8 weeksWhen lab values are nml, wean from iron supplementsRepeat labs in 6 months, monitor wt/ development
23Sickle cell diseaseSickle cell anemia (SS) is an inherited, autosomal recessive genetic disease that affects the RBC’s, which become acutely sickle-shaped.Involves RBCs and their ability to carry oxygenPathophysiology of the diseaseResults from a single amino acid substitution (valine for glutamine) in position 6 of the beta globin chain of hemoglobinWhat does this mean?...an unstable RBC w/ a shortened survival that under stress becomes sickle shapedBackground: Sickle cell disease is an inherited disorder of hemoglobin synthesis. The resulting abnormality produces a normocytic, hemolytic anemia with multiple diversely shaped RBCs that are susceptible to morphologically changing into a sickle shape. The sickle cells produce thrombosis and obstruction in small vessels, leading to ischemia and necrosis of distal tissue.Pathophysiology: Sickle cell disease results from a single amino acid substitution (valine for glutamate) in position 6 of the beta-globin chain of hemoglobin. This genetic alteration yields an unstable RBC with a shortened survival that under stress becomes sickle shaped.
24Sickle cell disease How is the individual affected? Short Hgb life spanChronically anemicSickle cells risk being destroyed by the spleen…? ImplicationsDamage to the spleenw/o normal functioning spleen at risk for infectionsSickle cells only live for about 15 days, while normal hemoglobin can live up to 120 days. Also, sickle cells risk being destroyed by the spleen because of their shape and stiffness. The spleen is an organ that helps filter the blood of infections and sickled cells get stuck in this filter and die. Due to the decreased number of hemoglobin cells circulating in the body, a person with sickle cell disease is chronically anemic. The spleen also suffers damage from the sickled cells blocking healthy oxygen carrying cells. Without a normal functioning spleen, these individuals are more at risk for infections. Infants and young children are at risk for life-threatening infections.
25Sickle cell disease Age: Hematologic changes evident as early as 10 weeks, though usually delayed until age 6-12 months--? Why do you think this isBeta-chain (adult) hemoglobin is not prominent until the age of 3 monthsAge:Hematologic changes indicative of the disorder are evident as early as the age of 10 weeks, though symptoms are usually delayed until the age of 6-12 months….why do you think this is?? because of high levels of circulating fetal hemoglobin.Beta-chain (adult) hemoglobulin is usually not prominent until the age of 3 months.After infancy, erythrocytes of patients with sickle cell anemia contain approximately 90% hemoglobin S (HbS), 2-10% hemoglobin F (HbF), a normal amount of minor fraction of adult hemoglobin (HbA2), and no hemoglobin A (HbA).
26Difference in Hgb Normal Hgb cells Live for 120 days Round Smooth Flexible, like a letter “o” so they can move through vessels easilySickle Hgb cellsLive for about 15 daysStiffStickyForm into the shape of a sicle, or the letter “C”, when they loose OxygenCluster together…what would this lead to in the body?Sickle cell disease involves the red blood cells, or hemoglobin, and their ability to carry oxygen. Normal hemoglobin cells are smooth, round, and flexible, like the letter "O," so they can move through the vessels in our bodies easily. Sickle cell hemoglobin cells are stiff and sticky, and form into the shape of a sickle, or the letter "C," when they lose their oxygen. These sickle cells tend to cluster together, and cannot easily move through the blood vessels. The cluster causes a blockage and stops the movement of healthy, normal oxygen-carrying blood. This blockage is what causes the painful and damaging complications of sickle cell disease.
28Sickle Cell Anemia Sickling Triggered by fever, emotional stress, physical stressStates of hypoxiaHigh altitudesHypoventilationPoorly pressurized aircraftsDehydrationCold
29Sickle Cell Crisis SS crisis are acute exacerbations of the disease Vary in severity and frequencyThree most common typesVaso-occlusive crisisSequestration crisisAplastic crisis
30Vaso-occlusive Crisis “Pain Crisis” Aka thrombotic crisisMost common type of crisisPrecipitated by dehydration, exposure to cold, acidosis or localized hypoxemiaExtremely painfulCaused by stasis of blood w/ clumping of cells in the microciruclation, ischemia and infarctionThrombosis and infarction of tissue may occur if crisis not reversedClinical manifestations include fever, pain, tissue engorgement, swelling of joints, hands and feet, priapism and severe abdominal pain
31Splenic Sequestration Life-threatening crisis: death can occur w/in hours; high mortality (up to 50%)Caused by pooling of blood in the spleenSpleen can hold up to 1/5th of body’s blood supply at one time—leads to CV collapseClinical manifestations include profound anemia, hypovolemia and shockOccurs b/t 4 months-3 yearsTx- blood transfusions, emergent splenectomy
32Aplastic CrisisDiminished erythropoiesis and increased destruction of RBCs(bone marrow depression resulting from a viral infection)Triggered by viral infection or depletion of folic acidClinical manifestations include profound anemia, pallor, fatigue
33Acute Chest SyndromeThis is similar to pneumonia, with symptoms such as difficulty breathing, chest pain and fever.It can be caused by an infection or by blocked blood vessels in the lung.This potentially life-threatening disorder should be treated in the hospital.Treatments may include antibiotics, blood transfusions, pain medications, oxygen and medicines that help open up blood vessels and improve breathing.
34Acute chest syndromeThe acute chest syndrome (ACS) in sickle cell disease (SCD) can be defined as:a new infiltrate on chest x-rayassociated with one or more NEW symptoms: fever, cough, sputum production, dyspnea, or hypoxia..A past history of an ACS is associated with early mortality compared to those who have never had an episode.The disorder is most common in the 2 to 4 year age group and gradually declines in incidence with age.ACUTE CHEST SYNDROME - when sickling is in the chest. This can be a life-threatening complication of sickle cell disease. It often occurs suddenly, when the body is under stress from infection, fever, or dehydration. The sickled cells stick together and block the flow of oxygen in the tiny vessels in the lungs. It resembles pneumonia and can include fever, pain, and a violent cough. Multiple episodes of acute chest syndrome can cause permanent lung damage.The acute chest syndrome (ACS) in sickle cell disease (SCD) can be defined as:a new infiltrate on chest x-rayassociated with one or more NEW symptoms: fever, cough, sputum production, dyspnea, or hypoxia.Recent data from the Clinical Course of Sickle Cell Disease Cooperative Study indicate that this complication occurs with an incidence of 10,500/100,000 patients/year(2). ACS occurs most often as a single episode, but certain patients have multiple episodes. A past history of an ACS is associated with early mortality compared to those who have never had an episode. The disorder is most common in the 2 to 4 year age group and gradually declines in incidence with age. It is believed that Hb F exerts a protective effect on those less than 2 years of age. Furthermore, the decline observed in older age groups is partially related to at least two other factors: (a) excess mortality in the group which had an ACS, and (b) fewer viral episodes in adults due to acquired immunity.
35Nursing Dx: Pain r/t sickling of RBCs Pain can occur in any organ or joint in the bodyPain can be reversedOxygenationHydrationPain ManagementRestMild pain episodes can be treated w/ OTC pain meds (tylenol, ibuprofen) and heating padsMore severe episodes require hospitalization and IV pain medsHydroxyurea1998 FDA approved this drug for use in tx of SCDPain episodes. This is the most common symptom of sickle cell disease. Some affected individuals have one or fewer pain episodes a year, while others may have 15 or more.1,2 Pain episodes usually last a few hours to a few days, but they may sometimes last for weeks. Pain can occur in any organ or joint in the body, wherever sickle-shaped cells pile up and block blood vessels. Mild pain episodes can be treated at home with over-the-counter pain medications (such as acetaminophen and ibuprofen) and heating pads. But some pain episodes may be severe and need to be treated in the hospital with strong pain-killing drugs given intravenously (in a vein). Until recently, there was no effective treatment to prevent the sickling that causes a pain crisis other than blood transfusions. A 1995 study reported that treatment with a drug called hydroxyurea reduced the number of pain episodes in some of the severely affected adults by about 50 percent.3 In 1998, the Food and Drug Administration (FDA) approved the use of this drug in patients over 18 years of age who have had at least three painful episodes in the previous year. A 2003 study that followed the same patients for nine years also found that treatment with hydroxyurea reduced deaths by 40 percent.4Several smaller studies have found that hydroxyurea is effective and well tolerated in children in the short term. However, the drug is not yet routinely recommended in children because it is not known whether it has any adverse effects on growth and development. Researchers continue to study the long-term safety of the drug in children.
36Nursing Dx: Risk for Infection Infants and young children w/ SCD are especially vulnerable to serious bacterial infectionsMajor cause of death in children w/ SCD Daily prophylactic Pen VK 125 mg BID from 2 months- 5 years of ageErythromycin for children w/ PCN allergies
37Nursing Dx: Risk for Infection Important to receive regular childhood vaccinations (Hib and PCV 7)In addition children w/ SCD should also receive a yearly flu shot (influenza) beginning at 6 mos of ageAnother type of pneumoccocal vaccine (PCV 23)—protects against additional bacteria b/t 2-5 years of ageMeningococcal vaccine (protects against meningitis at age 5 and beyond)It is important for babies and children with sickle cell disease to receive regular childhood vaccinations. The Hib (Hemophilus influenzae b) vaccine and the pneumococcal vaccine (Prevnar) help protect against potentially life-threatening bacterial infections. These vaccines are recommended for all babies starting at 2 months of age. Children with sickle cell disease should receive additional vaccinations. These include a yearly flu (influenza) shot, beginning at 6 months of age; another type of pneumococcal vaccine (23-valent pneumococcal vaccine), which protects against additional types of bacteria at 2 and 5 years of age; and the meningococcal vaccine, which protects against meningitis, at age 5.1
38Treatment for Sickle Cell Anemia Treatment consists of sx managementThe primary focus being on prevention of sickle cell crisisEducationBlood transfusionsHydration: Drinking plenty of water daily(8 to 10 glasses) or receiving fluid intravenously (to prevent and treat pain crises)Pain Managementhydroxyurea (a medication recently developed that may help reduce the frequency of pain crises and acute chest syndrome; it may also help decrease the need for frequent blood transfusions. The long-term effects of the medication are unknown.)
39Medications for SS anemia Hydroxyurea mg/kg/day to start and increase until therapeutic response (not more than 35 mg/kg)A chemotherapeutic drug used in CA txShown to decrease the number and severity of crisesIncreases production of Hemoglobin FSide effects include bone marrow supression, HA’s dizziness, N/V
40Clotting Disorders Hemophilia A (Factor VIII deficiency) Von Willerbrand DiseaseDisseminated Intravascular Coagulation (DIC)Idiopathic Thrombocytopenic Purpura (ITP)
41Hemophilia AHereditary bleeding disorder, that result from deficiency of specific clotting factorsHemophilia A aka Factor VIII is most common type80% of people w/ hemophiliaX-linked recessive traits, which manifests as affected males, and carrier females30% of cases are new mutationsRange of manifestations of disease from mild to severe
42Hemophilia A Clinical Manifestations Children usually do not manifest sxs until after 6 months of age (begin moving around, loosing teeth)Spontaneous bleedingHemarthrosis (bleeding into joint space)Deep tissue hemorrhageNosebleedsEasy bruising (ecchymosis)HematuriaLife-threatening bleeding includes:Head/ intracranialNeck and throatAbdominal/GIIliopsoas muscle with decrease hip ROM
43Hemophilia A Complications from bleeding include: Bone changes ContracturesDisabling deformities result from immobility and from bleeding into joint spacesMuscle contracturesJoint arthritisChronic painMuscle atrophyCompartment syndromeNeurologic impairment
44Hemophilia A Treatment: Factor Replacement Therapy Goal to control bleeding by replacing the missing clotting factor and prevent complicationsFactor Replacement TherapyOn demandProphyllaxisIV infusions consist ofFresh frozen plasmaCryoprecipitateFactor VIII
45Treatment of Hemophilia A Prophylaxis:Scheduled infusions of factor 2-3 X/ weekDDAVP (Desmopressin acetate)An analog of vasopressin, causes a 2-4 fold increase in factor VIIINot to be confused w/ DDAVP for nocturnal enuresisSynthetic vasopressinMOA: release of stores from endothelial cells raising factor VIII and vWD serum levelsAdministered IV, sub-Q or nasally (stimate)
46Treatment of Hemophilia A Amicar (epsilon amino caproic acid)AntifibrinolyticUses:Mucocutaneous bleedingmg/kg q 6 hoursContraindications:hematuria
47Hemophilia A Complications of Treatment: Inhibitors/antibody developmentIgG antibody to infused factor VIII concentrates which occurs after exposure to the extraneous VIII protein20-30% of pts w/ severe hemophilia ABlood-borne illnessesHep A,B and CHIV
48Hemophilia A Nursing Considerations Factor replacement given on timeLab monitoring as orderedIncrease metabolic states will increase factor requirementsFactor coverage for invasive proceduresDocument- infusion and response to txNO NSAIDSNO HEATNO IM injectionsUtilize Hemophilia Center staff for ???s
49Hemophilia A Nursing Considerations Avoid taking temperatures rectally or giving suppositoriesCheck Bp by cuff as little as possibleAvoid IM or subcutaneous injectionsUse only paper or silk tape for dressingsPerform mouth care w/ glycerin swabLimit venipuncturesDo not give aspirin
50Hemophilia A Psychosocial Issues GuiltChallenge of hospitalizationsControl issuesFinancial/ insurance challengesFeeling different/ unable to do certain activitiesCounseling needsRefer for genetic counseling after dx
51Von Willebrand Disease A hereditary bleeding disordervWF Involved w/ platelet adhesionMost common form of disorder is autosomal dominant traitDisease can occur in both males and females equallyManifestations:Easy bruisingEpistaxis
52Von Willebrand Disease Other clinical manifestations include:Gingival bleedingEcchymosisIncreased bleeding w/ lacerations or during surgery and dental extractionsMenorrhagia (increased menstrual bleeding)GI bleedingChildren w/ wWD usually do not have hemarthrosis
53Von Willebrand Disease Treatment:Similar to Hemophila ARestore clotting factor and prevent complications associated w/ bleedingInfusion of vWB protein concentrateDDAVPAmicar for mucous membrane bleedingNursing Management:Similar to Hemophilia A
54Disseminated Intravascular Coagulation (DIC) Life-threatening process which occurs as complication of other serious illnesses in infants and childrenMost common cause of DIC is infectionAn acquired pathologic process in which the clotting system is abnormally activated, resulting in widespread clot formation in the small vessels throughout the body.These changes slow blood circulation, cause tissue hypoxia and results in tissue necrosis.The circulating fibrin also interfere w/ clotting process and bleeding and hemmorrhage result
55DIC The sequence of events for DIC Clinical Manifestations: Treatment: – please see p 1027Clinical Manifestations:see chart on page 1028Treatment:Controlling bleeding, identifying and correcting the primary cause of the disorder, and preventing further activations of clotting mechanisms
56DIC Nursing Assessment and Diagnosis: Involves all body systems, so frequent thorough assessment of entire body is criticalObserve for petechiae, ecchymoses, and oozing every 1-2 hoursObserve for pooling of blood in dependent areasAssess IV site Q 15 minutes for oozingExamine stool for presence of bloodAssess extremities for cap refill, warmth and pulsesFrequently assess VS and LOCI’s and O’sMonitor O2 sat and ABG’sID family’s coping strategies and support systems
57Idiopathic Thrombocytopenic Purpura (ITP) Aka autoimmune thrombocytopenic purpuraMost common bleeding disorder in childrenOccurs in children 2-10 years-old, peaks b/t 2-5 y.oA disorder characterized by increased destruction of platelets in the spleen, even though plt production in the bone marrow is normalAutoimmunePlts are destroyed as a result of the binding of autoantibodies to PLT antigensAfter a viral illness
58ITP Clinical Manifestations: Multiple ecchymoses Petechiae Purpura (purplish areas where blood has collected d/t bleeding from blood vessels)Bleeding from gumsnosebleedsHematuriaheme in stools
59ITP Dx is made by Hx and PE and lab findings Tx: depends on PLT counts and clinical presentationCorticosteroidsIVIGPLT administration only if hemorrhage occursIf no response to therapy in 6mos-1 year, splenectomy may be tx of choiceSpontaneous remission in 90% of cases
60Nursing Care of the Child with a Hematologic Disorder Based on the DisorderRBC’sOxygenationCirculationFluidNutritionPain Management
61Nursing Care of a Child with a Hematologic Disorder Based on the DisorderWBC’sInfectionOxygenationNutritionPlatelets and bleeding disordersBleedingCirculationInjury Prevention
62Collaborative Care for a Child with a Hematologic Disorder Team ApproachFamily InvolvedDecisions w/ family and child