Chapter 49 BOOK 2

Function and Normal Blood Components

• The hematologic system directly or indirectly regulates most other body functions because blood is involved in every tissue and organ’s function.

• Blood is composed of two main portions:

  • Plasma (fluid portion)

  • Formed elements (cellular portion): red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes).

• Normal pediatric values (from Table 49–1):

  • Red blood cell (RBC): $3.8-5.5 \times 10^{12}/\mathrm{L}$

  • Hemoglobin (Hb): $11.5-14.5\ \mathrm{g/dL}$

  • Hematocrit (Hct): $33-43\%$

  • White blood cell (WBC): $4{,}000-12{,}000/\mu\mathrm{L}$

  • Platelets: $150{,}000-400{,}000/\mu\mathrm{L}$

• Leukopenia: a decrease in white blood cells, which can be caused by immune or bone marrow disorders.

• Thrombocytopenia: deficiency of platelets leading to bleeding disorders.

• Neonatal differences:

  • Platelet counts and many clotting factors are lower in newborns and rise with age.

• Sickle cell disease (SCD) as a focus in children is connected to genetic transmission and management of crises and complications.

Developmental Physiology of Hematopoiesis in Children

• Hematopoiesis timeline:

  • RBC production begins as early as the second week of gestation.

  • White blood cell and platelet production begin at 8 weeks gestation.

  • Early production occurs first in the yolk sac and liver; by 20–24 weeks, liver production declines as bone marrow becomes dominant.

• At birth:

  • Hematopoiesis primarily occurs in marrow of almost all bones.

  • Flat bones (sternum, ribs, pelvis, shoulder girdles, vertebrae, hips) retain most hematopoietic activity.

  • Newborns have elevated RBC counts due to high erythropoietin levels, stimulating red cell production.

  • When newborns begin breathing air and tissue oxygen increases, RBC production slows and RBC levels fall to about $9-11\ \mathrm{g/dL}$ by about 2–3 months, then rise toward adult levels.

  • Adolescent males typically have slightly higher RBC counts than females.

• WBC in newborns:

  • Highest at birth with large inter-individual variation; declines after birth and stabilizes by 1 week of age.

  • By 1 week, WBC values stabilize and remain stable until 1 year of age; then gradually decrease to adult values in adolescence.

• Platelets:

  • Newborns have lower platelet levels than older children and adults.

• Clinical relevance:

  • These developmental changes influence interpretation of complete blood counts in infants and children.

Anemias: Overview and Iron Deficiency Anemia (IDA)

• Anemia definition: a reduction in RBCs, hemoglobin quantity, and packed red cell volume below normal for age.

• Causes: loss or destruction of RBCs or decreased erythropoiesis; anemia can be a manifestation of an underlying disorder (e.g., lead poisoning, hypersplenism).

• Iron Deficiency Anemia (IDA):

  • Most common type of anemia and most common nutritional deficiency in children.

  • Etiology: blood loss, malabsorption, poor nutritional intake; increased physiologic demands during rapid growth; high-fat, vitamin-deficient adolescent diets; inadequate iron stores at birth (neonatal stores depleted by ~6 months if diet lacks iron).

  • Infant risk: not consuming iron-rich solids after 6 months if breast milk or iron-fortified formula alone; maternal iron deficiency or prematurity/multiples increases risk.

  • Screening and prevention: screen at ~12 months; re-screen if risk factors present; adolescent risk assessment annually; hematocrit or hemoglobin level used for screening; more detailed iron studies if abnormal.

  • Diet and management:

  • Dietary management is the long-term treatment: include iron-rich foods and foods rich in vitamin C to enhance iron absorption.

  • Infants >6 months: breast milk or iron-fortified formula and iron-fortified cereals; avoid cow’s milk in the first year to prevent GI blood loss contributing to anemia.

  • If older infant/toddler drinks large amounts of milk and avoids solids, restrict milk intake.

  • Adolescents: emphasize iron-rich foods and vitamin C (e.g., hamburgers with tomato).

  • Pharmacologic therapy:

  • Oral iron (elemental iron) typically as ferrous sulfate, dose about $3-6\ \mathrm{mg/kg/day}$.

  • Side effects: constipation, GI discomfort; encourage fluids and fiber; monitor for constipation.

  • Safety: store medicine safely to avoid accidental poisoning.

  • Expectation: increase iron intake and return hematocrit toward normal; reevaluate in ~6 months.

  • Special notes: nutritional screening often occurs in community settings (Head Start, WIC programs); when signs (low energy, pallor) appear, screen.

• Normocytic Anemia (brief):

  • Increased RBC destruction or decreased production; associated with inflammation/infection, renal failure, GI bleeding, G6PD deficiency, etc.; may present with hepatomegaly/splenomegaly; treatment targets underlying cause; may involve treating inflammation or infection and correcting iron stores if depleted.

• Clinical manifestations and diagnosis considerations for anemia: weight/height tracking, growth percentiles, developmental screening, and diet history.

Sickle Cell Disease (SCD)

• Genetics and pathophysiology:

  • SCD is a hereditary hemoglobinopathy with hemoglobin S (HbS) replacing normal Hb in RBCs.

  • HbS results from substitution of valine for glutamine at the beta-globin chain ( autosomal recessive ).

  • HbS polymerizes when deoxygenated, forming rod-like structures that sickle RBCs, causing vaso-occlusion, tissue ischemia, and infarction.

  • Sickled cells have shortened lifespan (≈ $120\ \mathrm{days}$) and are more fragile; chronic hemolysis leads to anemia.

• Epidemiology:

  • SCD affects about $100{,}000$ people in the United States; ~1 in 13 African Americans are carriers.

  • SCD trait (heterozygous) carriers usually asymptomatic except under extreme conditions.

  • If both parents have trait, the risk of an affected child is $25\%$ per pregnancy.

• Common genotypes:

  • HbSS (sickle cell anemia): most common; two HbS genes; crises common.

  • HbSC: one HbS and one HbC gene; milder anemia and crises about half as frequent as HbSS on average.

  • HbSβ+ and Hb0β (sickle beta-thalassemia): combinations with reduced or absent HbA; variable severity.

• Clinical features and organ involvement (pathophysiology of crises):

  • Painful vaso-occlusive crises (most common cause of hospitalization).

  • Splenic sequestration crisis (pooling of blood in spleen; can cause profound anemia, hypovolemia, shock).

  • Aplastic crises (often triggered by Parvovirus B19; temporary decreased RBC production).

  • Acute chest syndrome (ACS): new pulmonary infiltrate with fever and respiratory symptoms; life-threatening.

  • Cerebrovascular events (stroke) by age ~20; about 11% by age 20; cognitive impact possible.

  • Renal (enuresis, hematuria, inability to concentrate urine); priapism; bone/joint ischemia -> avascular necrosis; retinopathy; gallstones from chronic hemolysis.

• Clinical management overview:

  • Newborn screening for early diagnosis; confirmatory hemoglobin electrophoresis.

  • Acute crisis management: aggressive hydration, oxygenation, pain control; bed rest to reduce energy expenditure.

  • Analgesia: parenteral opioids (e.g., morphine, hydromorphone) around the clock or PCA; adjuncts include ketorolac or NSAIDs every 6 hours.

  • Infection prevention: prophylactic penicillin started in newborn period or upon diagnosis and continued until at least age 5 (and longer with splenectomy or pneumococcal sepsis history); ensure up-to-date vaccines (pneumococcal conjugate, Hib, HepB, influenza); children recommended pneumococcal vaccines (including 23-valent Pneumovax at ages 2 and 5 after first dose); meningococcal vaccination beginning at 2 months for those with asplenia.

  • Transfusions: blood transfusions improve tissue oxygenation, reduce sickling, correct anemia, and help prevent strokes; be mindful of iron overload from repeated transfusions; use iron chelation (deferoxamine or deferasirox) when needed.

  • Hydroxyurea: recommended for children with SCD starting around 9 months of age; increases fetal hemoglobin (HbF), which does not sickle, reducing crises and ACS frequency.

  • HSCT (hematopoietic stem cell transplantation): only known curative option; best outcomes in children with matched sibling donor; ~14% of affected children have a matched sibling; >90% 5-year survival rates after HSCT; eligibility depends on donor availability; long-term follow-up and risk of GVHD.

  • Newborn screening and early prophylaxis have improved life expectancy (median around 42 years for males, 48 years for females in some cohorts).

• Nursing assessment and care emphasis:

  • Thorough physiological assessment in known SCD patients; obtain detailed crisis history and precipitating events.

  • Monitor growth, development, and pain location/intensity; assess for dehydration and infection.

  • Ensure transfusion safety (two-RN check for ABO compatibility, saline infusion; avoid D5W in transfusion fluids).

  • Infection prevention and vaccination adherence; antibiotic prophylaxis; prompt antibiotic treatment when infection suspected.

  • Hydration and oxygenation to reduce crisis; educate families on hydration needs and trigger avoidance (heat, dehydration, high altitude, fever, stress).

  • Education for families on recognizing crisis triggers, managing pain at home, and when to seek care.

  • Discharge planning: home care teaching, recognizing signs of stroke, hydration management, school planning, and genetic counseling considerations.

• Special notes on HSCT in SCD:

  • Donor options: autologous (own marrow) or allogeneic (from matched donor: sibling, related or unrelated, cord blood possible).

  • Preparative conditioning includes chemotherapy and sometimes total body irradiation; isolation in a sterile unit; engraftment usually occurs within 2–4 weeks; pancytopenia lasts weeks; GVHD risk is a major late complication.

  • Post-discharge follow-up and education about signs of GVHD, infection risk, nutrition, and school reintegration.

Thalassemias

• Beta-thalassemias present as a spectrum:

  • Thalassemia minor/trait: mild anemia.

  • Thalassemia intermedia: moderate anemia; may require transfusions.

  • Thalassemia major: severe anemia requiring regular transfusions.

• General pathophysiology: defective synthesis of globin chains leads to abnormal RBCs with decreased lifespan; chronic anemia and compensatory hyperactivity of bone marrow.

• Diagnosis: hemoglobin electrophoresis shows decreased/absent one globin chain; ferritin and iron studies help manage iron overload risk from transfusions.

• Treatment and management:

  • Regular transfusions to maintain normal Hb/Hct; chronic transfusion programs are common for severe disease.

  • Iron chelation therapy (e.g., deferoxamine, deferasirox) to manage transfusional iron overload.

  • Splenectomy considered in splenomegaly with growth failure or significant anemia.

  • Hematopoietic stem cell transplantation (HSCT) as potential curative option in some cases.

• Nursing management: focus on transfusion safety, infection prevention, family support, and genetic counseling.

Hereditary Spherocytosis (HS)

• HS is a hemolytic disorder with spherical erythrocytes due to intrinsic membrane defects (spectrin deficiency common).

• Erythrocytes are sequestered and destroyed in the spleen; splenomegaly can occur.

• Clinical spectrum: asymptomatic to severe anemia requiring transfusions; gallstones and jaundice can occur.

• Management:

  • Folate supplementation; RBC transfusions as needed.

  • Splenectomy in severe disease or growth failure; prefer delaying until after age 6 to reduce infection risk.

• Nursing considerations: same care principles as anemia; monitor for splenic complications and infection risk.

Aplastic Anemia

• Aplastic anemia is a bone marrow failure resulting in deficiency of all blood cell types (pancytopenia).

• Etiology:

  • Often acquired (autoimmune) in ~80% of cases; can be congenital or drug/toxin-induced.

  • Viral triggers or exposure to radiation/chemotherapy can contribute.

• Symptoms: pallor, fatigue, dyspnea, infections (neutropenia), bleeding (thrombocytopenia).

• Diagnosis: CBC shows pancytopenia; bone marrow aspiration reveals fatty (yellow) marrow rather than red marrow.

• Treatment:

  • Supportive transfusions as needed.

  • Immunosuppressive therapy (e.g., ATG, cyclosporine) is effective in many children.

  • HSCT from an HLA-matched donor is the treatment of choice in many children with severe disease.

• Nursing management: infection prevention, transfusions, education, genetic counseling, and family support.

Bleeding Disorders: Hemophilia, Von Willebrand Disease, ITP, DIC

• Hemophilia A and B:

  • Hemophilia A: factor VIII deficiency; Hemophilia B (Christmas disease): factor IX deficiency.

  • X-linked recessive; predominantly affects males; carrier females may transmit the gene.

  • Clinical features: easy bruising, prolonged bleeding after circumcision or minor injuries, spontaneous joint bleeds (hemarthrosis) especially knees, ankles, elbows; deep muscle bleeds and intracranial hemorrhage possible.

  • Lab profile: low factor VIII (A) or IX (B); prolonged activated partial thromboplastin time (aPTT); normal PT, fibrinogen, and platelets.

  • Treatments:

  • Desmopressin (DDAVP) to release stored factor VIII in some mild/moderate hemophilia A cases.

  • Replacement therapy with recombinant factor VIII for Hemophilia A or IX for Hemophilia B.

  • Prophylaxis reduces bleeding episodes and joint damage.

  • Gene therapy research ongoing.

• Von Willebrand Disease (vWD):

  • Most common inherited bleeding disorder; autosomal dominant; deficiency or dysfunction of von Willebrand factor (vWF), carrier for factor VIII.

  • Clinical features: mucocutaneous bleeding (epistaxis, easy bruising), heavy surgical/dental bleeding; menorrhagia in teens.

  • Lab profile: decreased vWF antigen/activity; reduced ristocetin-induced platelet aggregation; variable aPTT.

  • Treatments: vWF concentrates; DDAVP to release stored vWF (often effective); factor VIII/vWF concentrates; supportive care.

• Immune Thrombocytopenic Purpura (ITP):

  • Autoimmune destruction of platelets; platelet count < $100{,}000/\mu\mathrm{L}$; commonly follows infection.

  • Management: steroids, IVIG, IV anti-D in selected cases; some cases become chronic (≥6 months).

• Disseminated Intravascular Coagulation (DIC):

  • Life-threatening acquired process with widespread clotting and subsequent bleeding.

  • Most common trigger is sepsis; other infections can trigger DIC.

  • Clinical manifestations: mucosal/gingival bleeding, petechiae, purpura, oozing from venipuncture, tachycardia, hypotension.

  • Management: treat underlying infection; replace platelets and clotting factors; careful use of heparin in some scenarios.

• Nursing considerations across bleeding disorders (patient-centered care):

  • Avoid rectal temperatures and unnecessary intramuscular injections; use subcutaneous injections when possible with firm pressure; schedule and perform injections with factor replacement ready; pressure for at least 5 minutes on puncture sites; avoid aspirin-containing products.

  • Encourage appropriate safe, noncontact activities; use protective equipment.

  • Educate families about recognizing bleeding, managing bleeding episodes, and when to seek care.

  • School planning and providing an individualized health plan; ensure coordination with teachers and school nurses.

Hematopoietic Stem Cell Transplantation (HSCT)

• HSCT basics:

  • Replacement of diseased or deficient marrow with healthy stem cells from bone marrow, cord blood, or peripheral blood.

  • Autologous HSCT: patient’s own marrow-derived cells; allogeneic HSCT: donor-derived (related or unrelated, sometimes matched cord blood).

• Donor matching:

  • HLA-matched sibling donor provides best outcomes; ~14% of children with SCD have a matched sibling donor.

  • Unrelated donors or cord blood options can be used when no match in family.

• Procedure overview:

  • Conditioning: chemotherapy with or without total body irradiation to eradicate diseased marrow and suppress the immune system.

  • Transplant infusion: donor stem cells infused intravenously; cells engraft in bone marrow within 2–4 weeks.

  • Post-transplant: pancytopenia lasts several weeks; risk of infection, anemia, and bleeding; risk of graft-versus-host disease (GVHD) is a major concern.

• Nursing considerations:

  • Strict isolation during conditioning and early engraftment; monitor organ function and hydration, nutrition, and infection signs.

  • Post-discharge: teach home care, medication administration, signs of GVHD, and when to seek care; coordinate follow-up and school reintegration.

  • Family support and psychosocial considerations are essential due to the lengthy, complex process.

• Major outcomes:

  • Goal is proper marrow function with normal blood cell production; overall success includes infection prevention, good nutrition, and prevention of GVHD.

Nutrition, Growth, and Development Considerations

• Growth monitoring: regular height/weight measurements; growth percentile tracking; nutritional assessment.

• Nutrition support across hematologic disorders: emphasize iron intake (for IDA), folate, vitamin C, and protein; monitor for constipation with iron therapy; hydration is critical in crises (especially SCD).

• Education needs: for families and school personnel; genetic counseling considerations for inherited disorders; ensure immunizations are up to date; newborn screening considerations; planning for long-term care and transitions to adulthood.

Focus Your Study: Key Points to Remember

• Erythrocytes carry oxygen from lungs to tissues; polycythemia is an excess of RBCs; anemia is a deficit.

• Leukocytes defend the body; five types with distinct functions; differential counts help identify causes (e.g., neutrophilia vs eosinophilia).

• Thrombocytes (platelets) are essential for coagulation; thrombocytopenia increases bleeding risk.

• Major childhood anemias include iron deficiency anemia, normocytic anemia, sickle cell disease, thalassemia, hereditary spherocytosis, and aplastic anemia.

• Sickle cell disease is a genetic autosomal recessive disease causing HbS and RBC sickling; crises include vaso-occlusive pain crises, splenic sequestration, aplastic crises, and acute chest syndrome; complications affect brain, eyes, bones, liver, spleen, kidneys, and gonads.

• Management of SCD includes newborn screening, hydration, oxygenation, pain control, infection prevention (including prophylactic penicillin and vaccines), hydroxyurea to raise HbF, and HSCT as potential cure in select cases.

• The thalassemias are inherited disorders of hemoglobin synthesis with varying severity; management includes transfusions and iron chelation; HSCT may be curative.

• Hereditary spherocytosis is a membrane defect causing hemolysis with splenomegaly; folate supplementation and splenectomy in select cases; infection risk management is important.

• Aplastic anemia is bone marrow failure with pancytopenia; immunosuppressive therapy and HSCT are key treatments; supportive care is essential.

• Bleeding disorders include Hemophilia A/B, von Willebrand disease, ITP, and DIC; management involves factor replacement, DDAVP where appropriate, avoidance of NSAIDs/aspirin, and infection control; genetic counseling and family support are important.

• HSCT offers potential cure for several hematologic diseases but requires careful donor matching, conditioning, infection prevention, and long-term follow-up.

• Nursing care emphasizes patient- and family-centered approaches, safety in transfusions, infection prevention, pain management, hydration, nutrition, growth monitoring, education, and psychosocial support.

Clinical Reasoning and Practice Questions

• Case-based considerations (SCD crisis management):

  • In a child like Michael with severe abdominal pain, prioritize pain control, hydration, oxygenation, and infection screening; assess for splenic sequestration or ACS as potential causes.

  • Transfusion decisions should account for anemia correction and potential for iron overload; monitor for transfusion reactions and ensure saline-based infusions.

• Questions for reflection:
  1) Besides correcting anemia, what is another reason a child with sickle cell disease would require a transfusion? (e.g., to improve tissue oxygenation, prevent stroke, manage acute crisis, or treat severe anemia.)
  2) What pathophysiological process could cause abdominal pain in a child with SCD (spleen-related sequestration, splenic infarction, ACS, or vaso-occlusion in abdominal vessels)?
  3) How does sickle cell disease affect multiple organ systems, and what are key organ-specific complications to monitor (brain/stroke, lungs/ACS, liver/hepatomegaly, spleen sequestration, kidneys, gonads, bones, eyes, etc.)?

Important Biologic and Therapeutic References to Note (as covered in the chapter)

• Newborn screening and early intervention improve outcomes in SCD (Minkovitz et al., 2016).

• Prophylaxis and vaccines are critical in SCD management (pneumococcal vaccines, Hib, HepB, influenza; meningococcal vaccine for asplenia).

• Transcranial Doppler ultrasound for stroke risk stratification in children with SCD aged 2–16 years; abnormal results indicate higher stroke risk and may lead to prophylactic transfusions (Barriteau & McNaull, 2018; Mack & Thompson, 2017).

• Hydroxyurea increases HbF and reduces vaso-occlusion and ACS frequency (Barriteau & McNaull, 2018; Mack & Thompson, 2017).

• HSCT cure potential is highest with HLA-matched siblings; long-term survival and GVHD risk require comprehensive planning (Kato et al., 2018; Wiebking et al., 2017).

• Iron chelation is necessary with chronic transfusion to prevent organ iron overload (e.g., deferoxamine, deferasirox) (Stanley, Friedman, et al., 2016).

• DDAVP is beneficial for some mild/moderate Hemophilia A patients and used to release stored factor VIII (Roman et al., 2018).

• DDAVP also used to manage von Willebrand disease in some cases (Williams & Lancashire, 2019).

• Aplastic anemia management hinges on HSCT when feasible; supportive care and immunosuppressive therapy are key components (Segel & Lichtman, 2016; Geng et al., 2018).

Quick Reference: Core Numerical and Conceptual Facts (LaTeX formatted)

• Hematopoiesis timeline: embryonic development begins RBC production by the second week; WBC and platelets by week 8; marrow becomes dominant by 20–24 weeks; newborn RBC elevation due to erythropoietin; RBC fall to $9-11\ \mathrm{g/dL}$ by 2–3 months; adult levels by adolescence.

• SCD genetics and risk: if both parents carry the trait, offspring risk of disease is $25\%$ per pregnancy.

• SCD prevalence and donor statistics: approximately $100{,}000$ individuals in the U.S. have SCD; about $14\%$ of affected children have a matched sibling donor.

• HSCT outcomes: >$90\%$ 5-year survival after HSCT in selected cases.

• Iron chelation therapy options: deferoxamine, deferasirox.

• Transfusion safety reminders: two-RN checks; use normal saline (not D5W) with transfusion; monitor for transfusion reactions.

• Age ranges for interventions: Penicillin prophylaxis from newborn period to at least age $5\,years$ (extend if asplenia or sepsis history); transcranial Doppler screening ages: $2-16\ years$.

End of Notes

Sickle Cell Disease (SCD)

• Genetics and Pathophysiology:

  • Hereditary hemoglobinopathy: hemoglobin S (HbS) replaces normal Hb in RBCs.

  • HbS results from substitution of valine for glutamine at the beta-globin chain (autosomal recessive).

  • HbS polymerizes when deoxygenated, forming rod-like structures that sickle RBCs, leading to vaso-occlusion, tissue ischemia, and infarction.

  • Sickled cells have shortened lifespan ($\approx 120\ \mathrm{days}$) and are more fragile; chronic hemolysis leads to anemia.

• Epidemiology:

  • Affects about $100{,}000$ people in the United States; $\approx$1 in 13 African Americans are carriers.

  • SCD trait (heterozygous) carriers are usually asymptomatic.

  • If both parents have trait, the risk of an affected child is $25\%$ per pregnancy.

• Common Genotypes:

  • HbSS (sickle cell anemia): most common; two HbS genes; frequent crises.

  • HbSC: one HbS and one HbC gene; milder anemia and crises about half as frequent as HbSS.

  • HbS$\beta$+ and Hb0$\beta$ (sickle beta-thalassemia): variable severity.

• Clinical Manifestations and Organ Involvement:

  • Painful vaso-occlusive crises (most common cause of hospitalization).

  • Splenic sequestration crisis (pooling of blood in spleen; profound anemia, hypovolemia, shock).

  • Aplastic crises (often triggered by Parvovirus B19; temporary decreased RBC production).

  • Acute chest syndrome (ACS): new pulmonary infiltrate with fever and respiratory symptoms; life-threatening.

  • Cerebrovascular events (stroke) by age $\approx$20 ($11\%$ by age 20); cognitive impact possible.

  • Renal (enuresis, hematuria, inability to concentrate urine); priapism; bone/joint ischemia ($\to$ avascular necrosis); retinopathy; gallstones.

• Clinical Therapy and Management:

  • Newborn screening for early diagnosis; confirmatory hemoglobin electrophoresis.

  • Acute crisis management: aggressive hydration, oxygenation, pain control; bed rest.

  • Analgesia: parenteral opioids (e.g., morphine, hydromorphone) around the clock or PCA; adjuncts (ketorolac or NSAIDs).

  • Infection prevention: prophylactic penicillin from newborn period until at least age $5\ \mathrm{years}$ (longer with splenectomy or pneumococcal sepsis history); up-to-date vaccines (pneumococcal conjugate, Hib, HepB, influenza); 23-valent Pneumovax at ages 2 and 5; meningococcal vaccination at 2 months for asplenia.

  • Transfusions: improve tissue oxygenation, reduce sickling, correct anemia, prevent strokes; monitor for iron overload; use iron chelation (deferoxamine or deferasirox) when needed.

  • Hydroxyurea: recommended for children with SCD starting around 9 months of age; increases fetal hemoglobin (HbF), reducing crises and ACS frequency.

  • Hematopoietic Stem Cell Transplantation (HSCT): only known curative option; best outcomes with matched sibling donor; >$90\%$ 5-year survival rates.

• Nursing Management:

  • Thorough physiological assessment, detailed crisis history and precipitating events.

  • Monitor growth, development, pain location/intensity; assess for dehydration and infection.

  • Transfusion Safety: two-RN check for ABO compatibility, saline infusion (avoid D5W).

  • Infection prevention, vaccination adherence, prompt antibiotic treatment.

  • Hydration and oxygenation to reduce crisis.

  • Family Education: hydration needs, trigger avoidance (heat, dehydration, high altitude, fever, stress), recognizing crisis triggers, managing pain at home, when to seek care.

  • Discharge Planning: home care teaching, recognizing signs of stroke, hydration management, school planning, genetic counseling.

Blood Transfusion Reactions

• The note emphasizes monitoring for transfusion reactions as a critical nursing action.

• Safety: Ensure two-RN check for ABO compatibility, use normal saline for infusion (avoid D5W).

Bleeding Disorders

• Hemophilia A and B:

  • Types: Hemophilia A (factor VIII deficiency); Hemophilia B (Christmas disease) (factor IX deficiency).

  • Genetics: X-linked recessive; predominantly affects males; carrier females transmit the gene.

  • Clinical Features: Easy bruising, prolonged bleeding (post-circumcision or minor injuries), spontaneous joint bleeds (hemarthrosis – knees, ankles, elbows), deep muscle bleeds, intracranial hemorrhage.

  • Lab Profile: Low factor VIII (A) or IX (B); prolonged activated partial thromboplastin time (aPTT); normal PT, fibrinogen, and platelets.

  • Treatments: Desmopressin (DDAVP) for some mild/moderate Hemophilia A (releases stored factor VIII); replacement therapy with recombinant factor VIII (Hemophilia A) or IX (Hemophilia B); prophylaxis to reduce bleeding and joint damage; gene therapy research.

• Von Willebrand Disease (vWD):

  • Most common inherited bleeding disorder; autosomal dominant.

  • Pathophysiology: Deficiency or dysfunction of von Willebrand factor (vWF), which carries factor VIII.

  • Clinical Features: Mucocutaneous bleeding (epistaxis, easy bruising), heavy surgical/dental bleeding; menorrhagia in teens.

  • Lab Profile: Decreased vWF antigen/activity; reduced ristocetin-induced platelet aggregation; variable aPTT.

  • Treatments: vWF concentrates; DDAVP (releases stored vWF, often effective); factor VIII/vWF concentrates; supportive care.

• Immune Thrombocytopenic Purpura (ITP):

  • Pathophysiology: Autoimmune destruction of platelets, typically following a viral infection, leading to a platelet count below $\approx 100{,}000/\mu\mathrm{L}$.

  • Clinical Manifestations: Petechiae, purpura, bruising, nosebleeds. Often acute onset.

  • Clinical Therapy/Management: Observation for mild cases, intravenous immunoglobulin (IVIG), anti-D antibody, corticosteroids. Splenectomy is reserved for severe, unresponsive cases.

• Disseminated Intravascular Coagulation (DIC):

  • Pathophysiology: A life-threatening disorder characterized by widespread activation of the coagulation system, leading to simultaneous excessive clotting and bleeding. Triggered by severe underlying conditions (e.g., sepsis, trauma, malignancy).

  • Clinical Manifestations: Petechiae, purpura, bleeding from multiple sites, signs of organ dysfunction due to microclot formation.

  • Clinical Therapy/Management: Urgent treatment of the underlying cause, supportive care including blood product transfusions (platelets, fresh frozen plasma, cryoprecipitate).

Hematopoietic Stem Cell Transplantation (HSCT)

• Basics: Replacement of diseased or deficient marrow with healthy stem cells from bone marrow, cord blood, or peripheral blood.

• Types:

  • Autologous HSCT: Uses the patient’s own marrow-derived cells.

  • Allogeneic HSCT: Uses donor-derived cells (related or unrelated, sometimes matched cord blood).

• Donor Matching: HLA-matched sibling donor provides best outcomes ($\approx 14\%$ of children with SCD have a matched sibling); unrelated donors or cord blood are options when no match in family.

• Procedure Overview:

  • Conditioning: Chemotherapy with or without total body irradiation to eradicate diseased marrow and suppress the immune system.

  • Transplant Infusion: Donor stem cells infused intravenously; cells engraft in bone marrow within 2–4 weeks.

  • Post-transplant: Pancytopenia lasts several weeks; risk of infection, anemia, and bleeding; graft-versus-host disease (GVHD) is a major concern.

• Nursing Considerations:

  • Strict isolation during conditioning and early engraftment.

  • Monitor organ function and hydration, nutrition, and infection signs.

  • Post-discharge: Teach home care, medication administration, signs of GVHD, and when to seek care; coordinate follow-up and school reintegration.

  • Family support and psychosocial considerations are essential.

• Outcomes: Goal is proper marrow function with normal blood cell production; overall success includes infection prevention, good nutrition, and prevention of GVHD.

Growth and Development (and Safety Alerts)

• Developmental Physiology of Hematopoiesis:

  • RBC production begins as early as the second week of gestation; WBC and platelet production by 8 weeks gestation.

  • Early production in yolk sac and liver; bone marrow becomes dominant by 20–24 weeks.

  • Newborns have elevated RBC counts due to high erythropoietin levels; RBC levels fall to about $9-11\ \mathrm{g/dL}$ by 2–3 months, then rise toward adult levels.

  • Newborns have lower platelet levels than older children and adults.

• Growth Monitoring: Regular height/weight measurements, growth percentile tracking, nutritional assessment.

• Safety Alerts and Considerations:

  • Medication Safety: Store medications (e.g., oral iron) safely to avoid accidental poisoning.

  • Infection Prevention: Critical in conditions like SCD and during HSCT.

  • Hydration: Emphasize critical role in managing crises (especially SCD).

  • Genetic counseling for inherited disorders.

  • Importance of newborn screening and immunizations.

  • Safe practices for transfusions (two-RN check, appropriate fluid use).

  • Education for families and school personnel on long-term care and transition to adulthood. The developmental changes in hematologic values influence interpretation of complete blood counts in infants and children.