• Pediatrics
  • Clinicals

Neonatal Jaundice: Physiological and Pathological Jaundice

  • Reading time: 4 minutes, 55 seconds
  • 1542 Views
  • Revised on: 2022-11-01

Neonatal jaundice is the term used when a newborn has an excessive amount of bilirubin in the blood. Bilirubin is a yellowish-red pigment that is formed and released into the bloodstream when red blood cells are broken down.

Jaundice comes from the French word jaundice, which means yellow; thus a jaundiced baby is one whose skin color appears yellow due to bilirubin.

Bilirubin level of more than 85 umol/l (5 mg/dL) manifests clinical jaundice in neonates whereas in adults a level of 34 umol/l (2 mg/dL) would look icteric.

Predisposing causes of Neonatal Jaundice

A newborn baby has a hemoglobin (Hb) level of 18-19g/dl. This is necessary during fetal life to
facilitate oxygen-carrying capacity.

As soon as the baby is born and able to breathe oxygen the high Hb level is not needed and starts
to drop.

In the first week of life, the baby’s Hb will drop to about 11g/dl and this breakdown of the fetal
RBC’s may cause bilirubin to exceed the plasma carrying capacity of the blood. Therefore causing Physiological jaundice.

What is bilirubin??

Bilirubin is a product of hemoglobin breakdown. Hemoglobin is contained in the red blood cells and it’s most important function is to carry oxygen to the tissues. When a red blood cell reaches the end of its life, the reticuloendothelial system takes it out of circulation. This consists of the liver and spleen.

The hemoglobin is broken down into its two constituents: Haem and Globin.

The globin is a protein that is re-used by the body.
The Haem is an iron compound and so can’t be re-used. It is broken down to be excreted.
Bilirubin is a product of this last process and the accumulation in the blood causes yellow staining on the skin.

Bilirubin toxicity

Bilirubin can cross the blood/brain barrier and stain the basal ganglia, hippocampus, cranial nerve nuclei, cerebellar nuclei, and inferior olivary nuclei. This staining is permanent,  which is why high serum bilirubin levels are so dangerous. Original yellow deposits fade leaving dead neurons resulting in permanent brain injury.

Types of Neonatal Jaundice

• Physiological Jaundice
• Pathological Jaundice

Physiological jaundice

Physiological jaundice occurs in the first few days after birth and will have cleared by day 10.

It occurs because of physiological changes taking place during the transition from intrauterine to neonatal life. This type of jaundice is the consequence of immature liver enzymes and high red cell mass.

Other Factors which may increase Physiological Jaundice
Prematurity
• Bruising
Polycythemia
• Breastfeeding

Pathological jaundice

Pathological jaundice refers to jaundice that arises from factors that alter the usual process involved in bilirubin metabolism in the liver. It is significant in the first 24 hours of life especially if there is Rhesus incompatibility.

It may persist more than 2 weeks in some conditions when the baby will be jaundice all over and may appear a muddy yellow color.

These conditions include:-

• Group incompatibility (Haemolytic Disease of the Newborn) Rhesus factor, ABO incompatibility
• Hypoxemia
• Sepsis
• Endocrine or metabolic disorders and bile duct obstruction
• Hypoglycemia

Management of neonatal Jaundice

The aim of the management of neonatal Jaundice is:-

To prevent bilirubin encephalopathy (kernicterus) developing as a result of high levels of serum bilirubin.
Treatment of underlying conditions.
Maintenance of hydration and nutrition.

Start investigations if:-

• Jaundice is significant in the first 24 hours
• Jaundice persists after 10 days
• If the SBR is above 250umol/l or less in preterm babies
• If Jaundice is present in a baby who is already ill.
• Ascertain mother's blood group for compatibility and rhesus antibody status.

Coombs's antibody status should be obtained from mothers' notes.
Check baby’s blood group for Rhesus status, and Hb in case the jaundice is caused by hemolysis causing anemia

Check baby for Infection

If the baby’s SBR is above the treatment line (depending on which charts your unit uses) Phototherapy can commence.

Phototherapy

The goal of phototherapy is to avoid concentrations that may result in kernicterus. Its effectiveness is related to the area exposed, radiant energy and wavelength 400-500 nanometers.

Blue light range Acts on unconjugated bilirubin converts it to biliverdin (more soluble and readily excreted in bile)

Phototherapy is indicated in:

  • Jaundice within 24hrs
  • Deep jaundice involving palms and soles
  • Prematurity and jaundice
  • Jaundice due to hemolysis

What are the adverse effects of Phototherapy?

  • Dehydration
  • Increased insensible water loss
  • loose stools
  • Irritability or lethargy
  • Skin rashes
  • Overheating
  • Retinal injury
  • Adverse effect on cell growth
  • Oxidize essential fatty acids, decreases vitamins and calcium in premature infants
  • Tanning/Bronze Baby Syndrome

You may need to increase the baby’s fluid depending on your unit's policy. (you need to be familiar with unit policy)

Indomethacin dislodges Bilirubin from its plasma binding site so it increases SBR levels.
You may require I.V. access.
You may need to pass an Ng/Og tube.

Once Phototherapy has commenced you need to take an SBR at regular intervals the frequency depending on how high it is.

If the therapy that is being given isn’t reducing the SBR you may need to consider an Exchange
Transfusion.

The decision to exchange transfuse is not just determined by the level but by the rate of which the increase, which is why it is so important to plot SBR result on a time/SBR level graph.

Consider at serum unconjugated bilirubin concentrations of 400-430 umol/L.

Exchange transfusion involves slow removal of aliquots (10mls) from an artery and simultaneous injection into a vein 2. Serial withdrawal and injection of aliquots (5-20 ml) through umbilical vein.

Therefore after a few days of treatment, jaundice will subside and the treatment can be discontinued.

Phenobarbital Accelerates metabolic pathways for bilirubin clearance
Tin-mesoporphyrin inhibits heme oxygenase
IV gamma globulin inhibits hemolysis
Activated Charcoal binds bilirubin in the intestine


Article Details

Free Plan article
  • Clinicals
  • Pediatrics
  • 0.50 Points
  • Free
About The Author
author

Dan Ogera

Chief Editor

Most Popular Posts

Slide Presentations