Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
29 Cards in this Set
- Front
- Back
How is hyperbilirubinemia defined?
|
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 |
|
What is the pathophysiology of normal bilirubin transport?
|
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.
|
|
Define total serum bilirubin.
|
Sum of direct and indirect bilirubin
|
|
Define Direct Coomb's test.
|
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 |
|
Define Indirect Coomb's test.
|
Measures amount of Rh positive antibodies in mother's blood
|
|
What is physiologic jaundice and how often does it occur?
|
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 |
|
What are the bilirubin levels for physiologic jaundice?
|
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) |
|
What is pathologic jaundice and when can it occur?
|
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 |
|
What are the signs and symptoms of pathologic jaundice?
|
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 |
|
What is Rh incompatibility?
|
Mother forms antibodies against the fetal blood cells
Rh-positive offspring of an Rh-negative mother is at risk |
|
Define erythroblastosis fetalis.
|
Fetus is overcompensating for the anemia by producing large numbers of immature erythrocytes to replace those hemolyzed
|
|
What are the signs of hydrops fetalis?
|
Marked anemia, hypoxia
Cardiac compensation Cardiomegaly Hepatosplenomegaly |
|
What causes 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 |
|
How does acute bilirubin encephalopathy occur?
|
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 |
|
What are the symptoms of acute bilirubin encephalopathy in phase 1?
|
Hypotonic
Lethargic Poor suck Depressed or absent Moro reflex |
|
What are the symptoms of acute bilirubin encephalopathy in phase 2?
|
High-pitched cry
Opisthotonos (severe muscle spasm causing back to arch acutely) Spasticity Hyperreflexia Fever Seizures |
|
What is kernicterus and what conditions arise with this disease?
|
Describes chronic & permanent results
Those that don't die may have mental retardation, cerebral palsy, or high-frequency deafness |
|
What are the predisposing factors to kernicterus?
|
Hypoxia
Acidosis Hypothermia Hypoglycemia Rh or ABO incompatibility |
|
What is the treatment for hyperbilirubinemia?
|
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 |
|
What nursing interventions are involved with phototherapy?
|
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 |
|
When is exchange transfusion used?
|
When phototherapy is unsuccessful at reducting the unconjugated bilirubin levels
|
|
What is exchange transfusion?
|
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 |
|
What complications can arise from exchange transfusion?
|
Hypervolemia
Hypovolemia Air emboli |
|
What parental teaching should be given for the fiberoptic blanket?
|
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 |
|
When and how is the RhoGAM shot administered to Rh sensitive mothers?
|
300 mcg, IM
Give at 28 weeks gestation and Within 72 hours after birth if baby is Rh positive |
|
What causes hyperbilirubinemia?
|
A variety of factors, including maternal-fetal Rh and ABO incompatibility
|
|
What does erythroblastosis fetalis lead to?
|
Anemia
Edema The cytotoxic effects of unconjugated bilirubin |
|
What does the injection of RhoGAM do to the Rh-negative and Coomb's test-negative woman?
|
Bestows passive immunity and also minimizes the possibility of isoimmunization (Rh incompatibility)
|
|
What does exchange transfusion do to the infant?
|
Treats anemia and acidosis
Removes bilirubin, maternal antibodies, and fetal RBCs that are beginning to hemolyze |