What is Jaundice?
Jaundice is a visible yellowing of the skin and eyes that occurs when bilirubin is deposited in tissues below the skin and in the sclera. Bilirubin is an orange­yellow coloured pigment of bile, formed when haemoglobin in red blood cells is broken down.

Some other useful definitions:
• Hyperbilirubinaemia:​High blood levels of bilirubin.
• Unconjugated hyperbilirubinaemia: ​Bilirubin in the blood that has not been metabolised properly by the body and is unable to be excreted from the body in urine/faeces. It can result in dangerous neurotoxic effects on the baby’s body. Neurotoxicity can lead to bilirubin encephalopathy, a condition which can cause seizures, coma, cerebral palsy, hearing impairments and developmental delay.
• Conjugated hyperbilirubinaemia: ​The bilirubin is metabolised but high levels of it have built up in the blood, usually because of some liver dysfunction.

Aspects of Initial Assessment in Neonatal Jaundice
History/Risk Factors for Neonatal Jaundice:
• When was jaundice first noticed? (Under 48 hours of age suggests haemolysis, after 3 days suggests a pathological cause.)
• Birth complications (e.g. cephalohaematoma).
• Prematurity
• Difficulties with breastfeeding
• Delayed passage of meconium
• Family history of diseases that cause haemolysis (e.g. spherocytosis, G6PD deficiency).
• Siblings who also had neonatal jaundice
• Maternal diseases (e.g. if mother has hepatitis).
• Ethnicity (e.g. African, Mediterranean, East Asian).

Examination:
• Pale­coloured stools or dark urine – seen in biliary obstruction.
• Unwell sick­looking infant – jaundice can be a result of sepsis and gastrointestinal obstruction.
• Plethora (reddish­purple colouring) – seen in polycythaemia.
• Enlarged liver on palpation – seen in hepatitis and certain metabolic problems.
• Hydration status – dehydration may exacerbate jaundice.

Investigations
Useful blood tests:
• Serum bilirubin level (can measure both unconjugated and conjugated bilirubin)
• FBP, UEC, LFTs, CRP, venous blood gas, glucose, TFTs, G6PD, alpha 1­antitrypsin levels
• Blood cultures (as part of a septic screen)
• Viral serology
• Group + hold, Coombs test

Other investigations that may be needed:
• Abdominal USS (particularly to look at the liver/gallbladder/biliary tract)
• Urine M/C/S

Management Options
Treat the cause – some examples include:
• Sepsis (severe infection):​Give antibiotic therapy.
• Biliary Atresia​(a disease where the baby’s bile ducts are absent or blocked): Needs surgery (Kasai procedure).
• Breastfeeding failure:​This occurs when babies aren’t getting enough breast milk, and thereby lose a lot of weight, which causes increased concentrations of bilirubin. This should be managed by trying to increase the mother’s milk supply, increase the frequency of feeds, and improve the baby’s latching onto the breast (to enable good sucking). Adequate breast milk/formula aids elimination of bilirubin in urine/faeces.

Phototherapy
• The act of using visible light (normally blue­green coloured) to treat severe neonatal jaundice.
• Purpose: To help prevent neurotoxicity from high levels of unconjugated bilirubin in the blood.
• How: Exposing the skin to the blue­green light results in conversion of unconjugated bilirubin, making it water soluble and able to be excreted from the body.
• Safe and effective – potential problems which need monitoring for include: overheating, diarrhoea, rash and damage to the retina.
• Babies should continue breastfeeding during this time.
• Decreases the chance of needing to give exchange transfusions (see below).
• Note: This is not the same as sunlight exposure, which is NOT advised for the treatment of neonatal jaundice. Sunlight is a source of multiple light wavelengths, and only a limited amount of such is suitable for managing jaundice. Sunlight also carries the risk of sunburn.

Exchange Transfusion
• The process of removing part of the baby’s blood and replacing it with donor blood.
• Purpose: To remove toxins or abnormal blood components (in this case, excess bilirubin).
• The Consultant Neonatologist will decide if an exchange transfusion should be performed, based on serum bilirubin level trends, the clinical symptoms of the baby, and any other underlying conditions.
• Potential complications: Low or high blood pressure, low or high blood sugar levels, hyperkalaemia, hypocalcaemia, thrombosis, air emboli, haemorrhage, arrhythmias, bradycardia, necrotising enterocolitis, septicaemia, hypo­ or hyperthermia, bronze
baby syndrome.

Follow­up
All babies with jaundice will need to be re­examined by a health care professional (e.g. a doctor, visiting midwife or child health nurse) a few days post­discharge from hospital. Assessment will include the following:
• Baby’s growth chart/rate of weight gain
• How much milk or formula the baby has been drinking each day
• Urine/bowel habits and the colour of urine/faeces
• Whether or not jaundice is still present
• May or may not need blood bilirubin level re­checked


Sources
• http://www.rch.org.au/clinicalguide/guideline_index/Jaundice_in_Early_Infancy/
• http://www.rch.org.au/rchcpg/hospital_clinical_guideline_index/Phototherapy_for_neonatal_jaundice/
• https://www.health.qld.gov.au/qcg/documents/g_jaundice5-1.pdf
• http://www.kemh.health.wa.gov.au/services/nccu/npw/docs/3_hyperbilirubinaemia__and__neonatal_jaundice.pdf
• http://www.uptodate.com/contents/jaundice-in-newborn-infants-beyond-the-basics
• http://www.rch.org.au/uploadedFiles/Main/Content/neonatal_rch/EXCHANGE_TRANSFUSION.pdf