1. Chapter 36
Hemolytic Disorders

2. Learning Objectives
Differentiate between physiologic and pathologic jaundice in the newborn.
Develop a nursing plan of care for preventing, identifying, and managing neonatal hyperbilirubinemia.
Compare Rh and ABO incompatibility and the implications for neonatal outcomes.
Explain nursing management to prevent the pathologic consequences of hyperbilirubinemia.
Review prenatal diagnosis of neonatal disorders.

3. Hyperbilirubinemia: Overview
Bilirubin level in blood is increased.
Characterized by yellow discoloration of the skin, mucous membranes, sclera, and various organs
Referred to as jaundice or icterus
Caused by an accumulation of unconjugated bilirubin and hemolyzed red blood cells (RBCs) under the skin

4. Hyperbilirubinemia Physiologic jaundice
Occurs in about 66% of healthy term newborns
Almost all preterm infants
Typically arises more than 24 hours after birth
Manifested by progressive increase in unconjugated bilirubin level in cord blood

5. Hyperbilirubinemia (Cont.)
Pathologic jaundice (Cont.)
Level of serum bilirubin that, if left untreated, can result in kernicterus
Acute bilirubin encephalopathy describes the acute central nervous system manifestations seen in the first weeks after birth.
Kernicterus is used to describe the chronic and permanent results of bilirubin toxicity.

6. Hyperbilirubinemia (cont)
Acute Bilirubin Encephalopathy
Caused by the deposition bilirubin in the brain, especially within the basal, ganglia, cerebellum, and hippocampus
Deposition can occur because unconjugated bilirubin is highly lipid soluble, making it capable of crossing the blood brain barrier if it is not bound by protein
Concentration of unconjugated bilirubin reaches toxic levels, it results in the yellowish staining of the brain tissue and the necrosis of neurons

7. Hyperbilirubinemia (cont)
Acute Bilirubin Encephalopathy (Kernicterus)
Clinical manifestations typically appear between 2 and 6 days after birth and go through several phases as the disease progresses:
First phase the newborn is hypotonic and lethargic and show a poor suck and depressed or absent Moro reflex
Appearance of a high-pitched cry, severe muscle spasm that causes the back to arch acutely, spasticity, hyperreflexia, and often by fever and seizures

8. Hyperbilirubinemia (cont)
Kernicterus
Irreversible chronic sequela of bilirubin toxicity
Over the first year of life
Characteristic findings of hypotonia
Active deep tendon reflexes,
Persistent tonic neck reflex

9. Hyperbilirubinemia (cont)
Kernicterus
Difficulty meeting developmental milestones
Fully developed encephalopathy include this
Treatment is supportive

10. Hyperbilirubinemia (Cont.)
Pathologic jaundice (Cont.)
Serum bilirubin concentrations of greater than 5 mg/dl in cord blood
Clinical jaundice evident within 24 hours of birth
Total serum bilirubin levels increasing by more than 5 mg/dl in 24 hours or increasing at a rate of 0.5 mg/dl/hr
A serum bilirubin level in a term newborn that exceeds 12.9 mg/dl at any time
A serum bilirubin level in a preterm newborn that exceeds 15 mg/dl at any time
Any case of visible jaundice that persists for more than 14 days of life in a term infant

11. Hyperbilirubinemia (Cont.)
Hemolytic Disease of the Newborn
RH Incompatibility
Occurs when an Rh-negative mother has an Rh-positive fetus who inherits the dominant Rh-positive gene from the father
The formation of fetal blood cells begins as early as the eighth week of gestation and these cells pass through the placenta into the maternal circulation
Fetus is Rh-positive and the mother is Rh-negative, the mother forms antibodies against the fetal blood cells
First IgM antibodies that are too large to pass through the placenta
Then later, IgG antibodies that can cross the placenta
Process of antibody formation is called maternal sensitization

12. Hyperbilirubinemia (Cont.)
Hemolytic disease of the newborn
Rh incompatibility (isoimmunization)
Rh-positive offspring of an Rh-negative mother are at risk
Mother forms antibodies against the fetal blood cells.
Erythroblastosis fetalis
Hydrops fetalis
Intrauterine transfusion

13. Hyperbilirubinemia (Cont.)
Rh Incompatibility
Severe Rh incompatibility results in marked fetal hemolytic anemia, because the fetal erythrocytes are destroyed by maternal Rh-positive antibodies
Erythroblastosis fetalis- fetus compensates for the anemia by producing large numbers of immature erythrocytes to replace those hemolyzed
Hydrops fetalis- is the most severe form of this disease
Fetus has marked anemia, together with cardiac compensation, cardiomegaly, and hepatosplenomegaly

14. Hyperbilirubinemia (Cont.)
Hemolytic disease of the newborn (Cont.)
ABO incompatibility
Fetal blood type is A, B, or AB, and the maternal type is O.
Naturally occurring anti-A and anti-B antibodies are transferred across the placenta to the fetus.
Exchange transfusions required occasionally

15. ABO Incompatibility
Is more common than Rh incompatibility but causes less severe problems in the affected infant
Occurs if the fetal blood type is A,B, or AB and the maternal type is O
Incompatibility arises because naturally occurring anti-A and anti-B antibodies are transferred across the placenta to the fetus
First born infants may be affected, because mothers with type O already have anti-A and anti-B antibodies in their blood

16. Hyperbilirubinemia: Care Management
Determine blood type of woman prenatally
Assessment for risk factors
Rho(D) immunoglobulin
Coombs’ test
Exchange transfusion