Hyperbilirubinemia Flashcards
What is hyperbilirubinemia?
Elevated total serum bilirubin level
What defines hazardous hyperbilirubinemia?
TSB > 30 mg/dL
What is bilirubin?
A byproduct of RBC destruction which releases heme-containing proteins
What is jaundice?
Yellow color caused by the deposit of bilirubin in the skin
What is acute bilirubin encephalopathy?
Bilirubin toxicity with direct correlation to elevated levels of unconjugated bilirubin and symptoms
What are the phases of acute bilirubin encephalopathy?
- Phase 1: lethargy, hypotonia
- Phase 2: fever, retrocollis, hypertonia, opisthotonos, high pitched cry
- Phase 3: shrill cry, hearing and visual impairment, athetosis, apnea, seizures, coma, death
What is kernicterus?
Irreversible, chronic sequelae of bilirubin toxicity
What is unconjugated bilirubin?
Indirect bilirubin, fat soluble, produced by RBC destruction
What is conjugated bilirubin?
Direct bilirubin, transformed by liver to water soluble form
What is free bilirubin?
Indirect bilirubin which is not bound to albumin
What is the normal bilirubin production rate in neonates?
8 – 10 mg/kg/day
What is the binding capacity of bilirubin?
Bilirubin binds reversibly to albumin, with each molecule capable of binding ~ 2 molecules of bilirubin
What enzyme converts bilirubin in the intestine?
β-glucuronidase
What is the significance of G6PD deficiency in hyperbilirubinemia?
Recognized as one of the most important causes of hazardous hyperbilirubinemia in the US and worldwide
What are risk factors for developing significant hyperbilirubinemia?
- Lower gestational age
- Jaundice in the first 24 hours after birth
- Family history of phototherapy or exchange transfusion
- Exclusive breastfeeding with suboptimal intake
What characterizes physiologic (non-pathologic) jaundice?
- Otherwise healthy infant
- Direct coombs negative
- Develops at > 24 hours of age
- Total bilirubin < 12 mg%
What characterizes pathologic or hazardous jaundice?
- Appears at < 24 hours of age (term)
- Persists beyond normal time frame
- Rate of rise > 0.2-0.3 mg% per hour
What is RhoGAM?
Anti-D human gamma globulin given to mothers to prevent maternal production of anti-Rh(D) antibodies
What is the role of phototherapy in treating hyperbilirubinemia?
Begins based on gestational age, TSB, and presence of neurotoxicity risk factors
What are the three types of chemical reactions that occur during phototherapy?
- Photoisomerization
- Structural isomerization
- Photo-oxidation
What are the side effects of phototherapy?
- GI hypermotility: loose stools
- Lethargy or irritability
What is the recommended feeding support to prevent hyperbilirubinemia?
Exclusive breastfeeding and feeding upon demand at least 8 times in 24 hours
What is the significance of bilirubin levels in treatment decisions?
Decisions are guided by gestational age, TSB, and neurotoxicity risk factors
What is the purpose of the direct antiglobulin test (DAT)?
To determine if an infant has antibodies that could cause hemolytic disease
Fill in the blank: Kernicterus is caused by the transfer of _______ bilirubin into brain cells.
free (unbound and unconjugated)
True or False: Phototherapy is ineffective for lowering bilirubin levels.
False
What factors can influence bilirubin levels in infants?
- Gestational age
- Weight
- Infection
- Feeding
What is essential to ensure for a newborn’s health?
Adequate hydration
Hydration helps prevent complications related to hyperbilirubinemia.
What should be followed to monitor newborn health?
Bilirubin level
Monitoring bilirubin levels is crucial in detecting and managing jaundice.
What is a recommended practice to protect a newborn’s eyes during phototherapy?
Protect eyes with patches
Eye protection is necessary to prevent damage from phototherapy lights.
What is important to monitor in terms of a newborn’s intake?
Weight, voids, stools
Monitoring these factors helps assess the newborn’s wellbeing and hydration status.
What should be avoided when feeding a newborn with jaundice?
Sterile water or glucose water
These should not be used as they do not provide adequate nutrition.
What are some side effects of phototherapy?
Loose stools, lethargy, retinal damage, photosensitivity
These side effects can occur due to the effects of light therapy.
When can phototherapy be discontinued?
When TSB has decreased by at least 2 mg/dL below the threshold
This is a guideline for safely stopping phototherapy.
What is rebound hyperbilirubinemia defined as?
TSB concentration reaching the phototherapy threshold within 72-96 hours after discontinuation
Monitoring for rebound is important to prevent complications.
What is the escalation of care threshold for bilirubin levels?
2 mg/dL below the exchange transfusion threshold
This level indicates a need for urgent medical intervention.
What should be done if signs of bilirubin encephalopathy are present?
Urgent exchange transfusion
This procedure is critical to prevent permanent damage.
What is required for discharge planning for neonates?
Follow-up within 24 to 48 hours after discharge
This ensures monitoring of the newborn’s health post-discharge.
What should be documented at discharge?
Discharge exam, feeding, stooling, instructions
Documentation is essential for continuity of care.
Fill in the blank: _______ should be consulted for breastfeeding management.
Lactation consult
This helps ensure proper feeding practices for jaundiced infants.
What should be checked 12-24 hours after discontinuing phototherapy?
Bilirubin levels
This helps to assess for any rebound in bilirubin concentration.
