Nur 264 Unit 3 Hyperbilirubinemia

Front 1

How is hyperbilirubinemia defined?

Back 1

Bilirubin level in blood is increased

Characterized by jaundice of the skin, mucous membranes, sclera, and various organs

Caused primarily by elevated levels of unconjugated bilirubin in the skin

Front 2

What is the pathophysiology of normal bilirubin transport?

Back 2

RBCs are destroyed by macrophages in the spleen and bone marrow, releasing hemoglobin, which splits into heme & globin. The heme portion is converted into unconjugated bilirubin (insoluble) and transported to the liver. There it is conjugated & becomes water soluble bilirubin for excretion in the bile. It is then delivered into the small & large intestine where it is excreted as urobilinogen, urobilin and stercobilin, which gives normal urine, feces color respectively.

Front 3

Define total serum bilirubin.

Back 3

Sum of direct and indirect bilirubin

Front 4

Define Direct Coomb's test.

Back 4

Performed to determine if jaundice is due to hemolytic disease

Measures amount of Rh positive OR type A or B antibodies in baby's blood

Front 5

Define Indirect Coomb's test.

Back 5

Measures amount of Rh positive antibodies in mother's blood

Front 6

What is physiologic jaundice and how often does it occur?

Back 6

Occurs in about half of healthy term newborns

80% of preterm infants

Typically arises more than 24 hours after birth

Manifested by progressive increase in unconjugated bilirubin level in cord blood

Front 7

What are the bilirubin levels for physiologic jaundice?

Back 7

Normal cord blood
(Average bilirubin level 2 mg/dL)

Peaks between 60-72 hours in term infants
(5-6 mg/dL)
(Decreases to 2 mg/dL by day 5)

In Native Americans & Asians peaks 72-120 hours
(10-14 mg/dL)
(Decreases to 2 mg/dL by day 7-10)

Peaks around day 5 in preterm babies
(10-12 mg/dL and will take lower to correct due to immature liver)

Front 8

What is pathologic jaundice and when can it occur?

Back 8

Level of serum bilirubin that, if left untreated, can result in kernicterus

Develops in the first 24 hours & can persist for more than 1-2 weeks

Most common cause is Hemolytic Disease of the Newborn

Front 9

What are the signs and symptoms of pathologic jaundice?

Back 9

4 mg/dL bili in cord blood

Clinical jaundice within 24 hours of birth

Total serum bilirubin levels increase more than 5 mg/dL in 24 hours

Serum bili exceeding 15 mg/dL in term at any time; 10 mg/dL in preterm

Visibile jaundice continues at 10 days old for term and 21 days for preterm

Front 10

What is Rh incompatibility?

Back 10

Mother forms antibodies against the fetal blood cells

Rh-positive offspring of an Rh-negative mother is at risk

Front 11

Define erythroblastosis fetalis.

Back 11

Fetus is overcompensating for the anemia by producing large numbers of immature erythrocytes to replace those hemolyzed

Front 12

What are the signs of hydrops fetalis?

Back 12

Marked anemia, hypoxia

Cardiac compensation

Cardiomegaly

Hepatosplenomegaly

Front 13

What causes ABO incompatibility?

Back 13

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

Front 14

How does acute bilirubin encephalopathy occur?

Back 14

Bilirubin deposits in the brain producing cerebral damage and usually death

Unconjugated bilirubin is highly lipid soluble, crossing the blood brain barrier when not bound to protein

Can develop in newborns who show no apparent signs of clinical jaundice

Associated with acute and long-term symptoms of neurological damage

Never present at birth

Front 15

What are the symptoms of acute bilirubin encephalopathy in phase 1?

Back 15

Hypotonic

Lethargic

Poor suck

Depressed or absent Moro reflex

Front 16

What are the symptoms of acute bilirubin encephalopathy in phase 2?

Back 16

High-pitched cry

Opisthotonos
(severe muscle spasm causing back to arch acutely)

Spasticity

Hyperreflexia

Fever

Seizures

Front 17

What is kernicterus and what conditions arise with this disease?

Back 17

Describes chronic & permanent results

Those that don't die may have mental retardation, cerebral palsy, or high-frequency deafness

Front 18

What are the predisposing factors to kernicterus?

Back 18

Hypoxia

Acidosis

Hypothermia

Hypoglycemia

Rh or ABO incompatibility

Front 19

What is the treatment for hyperbilirubinemia?

Back 19

Goal: prevent bilirubin neurotoxic effects

Early feedings promote stooling

Primary: Phototherapy
(application of fluorescent light to exposed skin, which promotes bilirubin excretion)

Fiberoptic blanket

Pharmacological management: Phenobarbital

Exchange transfusion

Front 20

What nursing interventions are involved with phototherapy?

Back 20

Place infant under lights nude (cover genetalia), repositioning frequently to expose all body surfaces to light

Eye shields are mandatory
(if disappears around eyes but not extremities, readjust eye shields)

Accurately chart times that phototherapy is started and stopped;
Proper shielding of eyes;
Type of lamp;
Number of lamps;
Distance between surface of lamps and infant (should be <18 inches);
Any side effects

Frequent loose stools may indicate accelerated bilirubin removal
(Assess for perianal irritation, keeping skin clean and dry)
(Monitor for dehydration: I&Os)

Once discontinued, observe for rebound effect which is usually transient and will resolve without resuming therapy

Front 21

When is exchange transfusion used?

Back 21

When phototherapy is unsuccessful at reducting the unconjugated bilirubin levels

Front 22

What is exchange transfusion?

Back 22

Alternately remove a small amount of infant's blood and replace it with small amount of donor blood

Purpose: Prevent accumulation of bilirubin in the blood above a dangerous level

O negative blood is used

Front 23

What complications can arise from exchange transfusion?

Back 23

Hypervolemia

Hypovolemia

Air emboli

Front 24

What parental teaching should be given for the fiberoptic blanket?

Back 24

As much of infant skin on lighted section of pad

Can be discontinued for brief periods of time without harm

Call if:
Change in activity level
Temperature not maintained at 97-100
Feeding poorly
Not voiding 6 times per day or none in 6 hrs
Infant vomiting of feeding 2 or more times

Front 25

When and how is the RhoGAM shot administered to Rh sensitive mothers?

Back 25

300 mcg, IM

Give at 28 weeks gestation and
Within 72 hours after birth if baby is Rh positive

Front 26

What causes hyperbilirubinemia?

Back 26

A variety of factors, including maternal-fetal Rh and ABO incompatibility

Front 27

What does erythroblastosis fetalis lead to?

Back 27

Anemia

Edema

The cytotoxic effects of unconjugated bilirubin

Front 28

What does the injection of RhoGAM do to the Rh-negative and Coomb's test-negative woman?

Back 28

Bestows passive immunity and also minimizes the possibility of isoimmunization (Rh incompatibility)

Front 29

What does exchange transfusion do to the infant?

Back 29

Treats anemia and acidosis

Removes bilirubin, maternal antibodies, and fetal RBCs that are beginning to hemolyze