Risk factors for hyperbilirubinaemia

• <38 weeks’ gestation
• Previous sibling required treatment for jaundice
• Mother intends to breastfeed exclusively
• Visible jaundice in baby aged <24 hr 

Risk factors for kernicterus

• High bilirubin level (>340 micromol/L in term baby)
• Rapidly rising bilirubin level (>8.5 micromol/L/hr)
• Clinical features of bilirubin encephalopathy

Symptoms and signs

• When looking for jaundice (visual inspection):
  • check naked baby in bright and preferably natural light
  • examine the sclerae and gums, and press lightly on skin to check for signs of jaundice in 'blanched' skin

Assess

• Pallor (haemolysis)
• Poor feeding, drowsiness (neurotoxicity)
• Hepatosplenomegaly (blood group incompatibility or cytomegalovirus)
• Splenomegaly (spherocytosis)

Causes

• Physiological
• Prematurity
• Increased bilirubin load: 
  • blood group incompatibility (Rhesus or ABO)
  • G6PD deficiency and other red cell enzyme deficiencies
  • congenital spherocytosis
  • cephalhaematoma, bruising
• Rarely infection (e.g. UTI, congenital infection)
• Metabolic disorder

Persistent jaundice after aged 14 days (see Liver dysfunction in preterm babies) guideline

• Breast milk jaundice
• Hypothyroidism 
• Liver disease (e.g. extra hepatic biliary atresia and neonatal hepatitis) 
• Alpha-1-antitrypsin deficiency 
• Galactosaemia 
• TPN-induced cholestasis 

Investigations

Assessment of jaundice

• Babies aged <72 hr, at every opportunity (risk factors and visual inspection)
  • do not routinely measure bilirubin in babies not visibly jaundiced
• Babies with suspected or obvious jaundice, measure and record bilirubin level urgently
  • <24 hr: within 2 hr 
  • ≥24 hr: within 6 hr
• If serum bilirubin >100 micromol/L in first 24 hr 
  • measure 6-hrly until level is both below treatment threshold and stable/falling 
  • interpret result in accordance with baby’s age and gestation see threshold graph (http://www.nice.org.uk/guidance/CG98 under 'Tools and resources' then 'CG98 Neonatal Jaundice: treatment threshold graphs')
  • urgent medical review as soon as possible (and within 6 hr, or 2 hr if baby aged <24 hr)
• Interpret bilirubin result in accordance with baby’s gestational and postnatal age according to threshold graph

Use of transcutaneous bilirubinometer

• May be used for initial bilirubin measurement for babies aged >24 hr and gestation ≥35 weeks
• If reading >250 micromol/L check serum bilirubin
• If serum bilirubin ≥ treatment threshold, use serum bilirubin for all subsequent measurements

Jaundice approaching treatment level

• If baby well, ≥38 weeks, aged >24 hr and 
  • serum bilirubin ≤50 micromol/L below treatment threshold, repeat measurement in 18 hr if risk factors and 24 hr if no risk factors 
  • serum bilirubin >50 micromol/L below treatment threshold, no further routine measurements required

Jaundice requiring treatment

• Total bilirubin
• Baby’s blood group and direct Coombs test (interpret result taking into account strength of reaction and whether mother received prophylactic anti-D immunoglobulin during pregnancy)
• Mother’s blood group and antibody status (should be available from maternal healthcare record)
• PCV 

Plus (if clinically indicated)

• Full infection screen (in an ill baby)
• G6PD level and activity (if indicated by ethnic origin: Mediterranean, Middle Eastern, South East Asian)
• FBC and film

Persistent jaundice >14 days term baby; >21 days preterm baby (see Liver dysfunction in preterm babies) guideline

• Total and conjugated bilirubin
• Examine stool colour
• FBC
• Baby’s blood group and direct Coombs test (interpret result taking into account strength of reaction and whether mother received prophylactic anti-D immunoglobulin during pregnancy) [see Blood group incompatibilities (including Rhesus disease) guideline]
• Ensure routine metabolic screening performed (including screening for hypothyroidism) 
• Urine culture

Second line investigations (not in NICE guideline)

• Liver function tests (ALT, AST, albumin, GGT)
• Coagulation profile
• G6PD screen in African, Asian or Mediterranean babies
• Thyroid function tests: ask for ‘FT4 priority and then TSH’
• Congenital infection screen
• Urine for CMV PCR, toxoplasma ISAGA-IgM and throat swab for HSV culture/PCR
• Metabolic investigations e.g:
  • blood galactose-1-phosphate
  • urine for reducing substances
  • alpha-1-antitrypsin 

Babies ≥38 weeks' gestation

• Use conventional blue light phototherapy (not fibre optic) as treatment of choice
• Use continuous multiple phototherapy for babies who:
  • fail to respond to conventional phototherapy (bilirubin does not fall within 6 hr of starting treatment) 
  • have a rapid rise in bilirubin (>8.5 micromol/L/hr)
  • have a bilirubin level within 50 micromol/L of exchange transfusion threshold at 72 hr
  • when level falls to >50 micromol/L below exchange transfusion threshold reduce intensity of phototherapy 
• If exchange transfusion threshold crossed see (see Exchange transfusion guideline)

Babies <38 weeks’ gestation

• Use fibre optic or conventional blue light as first line treatment
  • based on gestational age and postnatal age, use threshold graphs (http://www.nice.org.uk/guidance/CG98 under ‘Tools and resources’ then 'CG98 Neonatal Jaundice: treatment threshold graphs') to determine threshold for phototherapy
  • use gestational age at birth, not corrected gestational age
• Indications for multiple phototherapy as term babies

Management during phototherapy

• Offer parents information on procedure (www.nice.org.uk/guidance/cg98/resources/jaundice-in-newborn-babies-318006690757)
• Unless other clinical conditions prevent, place baby in supine position 
• Ensure treatment applied to maximum area of skin
• Monitor baby’s temperature
• Monitor hydration by weighing baby daily and assessing wet nappies 
• Use eye protection and give routine eye care
• Provided bilirubin not significantly elevated, encourage breaks of up to 30 min for breastfeeding, nappy change and cuddles 
• Do not give additional fluids routinely
• During multiple phototherapy:
  • do not interrupt for feeds
  • continue lactation/feeding support so that breastfeeding can recommence when treatment stops

Monitoring during phototherapy

• Repeat serum bilirubin 4–6 hr after starting treatment
• Repeat serum bilirubin 6–12 hrly when bilirubin stable or falling
• Stop phototherapy once serum bilirubin has fallen to at least 50 micromol/L below threshold
• Check for rebound jaundice with repeat serum bilirubin 12–18 hr after stopping phototherapy. Babies do not necessarily need to remain in hospital for this to be done 

• GP follow-up with routine examination at 6–8 weeks 
• If exchange transfusion necessary or considered, request developmental follow-up and hearing test 
• In babies with more than weakly positive Coombs test who require phototherapy:
  • check haemoglobin at aged 2 and 4 weeks due to risk of continuing haemolysis 
  • give folic acid 1 mg daily
• Treatment graphs giving the phototherapy and exchange transfusion limits for each gestational age can be printed from http://www.nice.org.uk/guidance/CG98 under 'Tools and resources' then 'CG98 Neonatal Jaundice: treatment threshold graphs'