What is the immediate management for a newborn suspected of having erythroblastosis fetalis (hemolytic disease of the newborn)?

Immediate Management of Erythroblastosis Fetalis (Hemolytic Disease of the Newborn)

Admit the infant immediately for intensive phototherapy and prepare for possible exchange transfusion if total serum bilirubin (TSB) is ≥20 mg/dL or if any signs of acute bilirubin encephalopathy are present, regardless of bilirubin level. 1

Initial Assessment and Laboratory Evaluation

Obtain the following laboratory tests immediately upon suspicion:

• TSB and direct bilirubin levels to quantify hyperbilirubinemia and exclude conjugated disease 1
• Maternal and infant blood type (ABO, Rh) to identify isoimmune incompatibility 1
• Direct antibody test (Coombs') to confirm immune-mediated hemolysis 1
• Complete blood count with differential and peripheral smear to assess degree of anemia and red cell morphology 1
• Reticulocyte count to evaluate hemolysis severity 1
• Serum albumin because levels <3.0 g/dL markedly increase neurotoxicity risk 1
• G6PD testing if the infant is of Mediterranean, African, Middle Eastern, or Asian descent, or if bilirubin rises despite phototherapy 1

Critical warning: Do not wait for laboratory results to initiate phototherapy if TSB meets treatment thresholds or clinical jaundice is severe. 1

Immediate Phototherapy Protocol

Initiate intensive phototherapy using these specifications:

• Blue-green LED light (430-490 nm wavelength) delivering irradiance ≥30 µW/cm²/nm over maximal body surface area 1
• Remove the infant's diaper when bilirubin approaches exchange transfusion levels 1
• Position light source as close as safely possible to the infant 1
• Line the bassinet with reflective material (aluminum foil or white cloth) to enhance light delivery 1
• Add a fiber-optic pad beneath the infant as an adjunct to overhead phototherapy 1

Expected response: TSB should decline by ≥0.5-1 mg/dL per hour during the first 4-8 hours, or >2 mg/dL within 4-6 hours. 1

Intravenous Immunoglobulin (IVIG) Administration

Administer IVIG 0.5-1 g/kg intravenously over 2 hours if:

• TSB continues to rise despite intensive phototherapy, OR 1
• TSB is within 2-3 mg/dL of the exchange transfusion threshold 1

IVIG reduces the need for exchange transfusion in both Rh and ABO hemolytic disease. 1 Repeat the dose in 12 hours if bilirubin control remains inadequate. 1

Hydration and Feeding Management

• Continue breastfeeding or bottle-feeding (formula or expressed breast milk) every 2-3 hours during phototherapy 1
• If weight loss exceeds 12% of birth weight or clinical/biochemical dehydration is present, supplement with formula or expressed breast milk 1
• Initiate intravenous fluids if oral intake is inadequate 1

Do not provide water or dextrose water—these do not lower bilirubin and interfere with breastfeeding. 2

Bilirubin Monitoring Schedule

Re-measure TSB based on initial level:

• If TSB ≥25 mg/dL: Repeat within 2-3 hours 1
• If TSB 20-25 mg/dL: Repeat within 3-4 hours 1
• If TSB <20 mg/dL: Repeat in 4-6 hours 1
• Continue monitoring every 8-12 hours once TSB is declining 1

Failure of TSB to decrease or continued rise despite intensive phototherapy strongly indicates ongoing hemolysis and requires immediate escalation. 1

Exchange Transfusion Preparation and Indications

Prepare for exchange transfusion immediately if:

• TSB ≥25 mg/dL at any time (medical emergency) 1
• TSB ≥20 mg/dL in a sick infant or infant <38 weeks gestation 1
• Any signs of acute bilirubin encephalopathy (lethargy, poor feeding, high-pitched cry, hypotonia, hypertonia, opisthotonus, retrocollis, fever) regardless of bilirubin level 1
• TSB continues to rise despite intensive phototherapy and IVIG 1

Critical action steps:

• Obtain type and crossmatch immediately 1
• Admit directly to a pediatric service with NICU capabilities—do not route through the emergency department, as this delays treatment 1
• Exchange transfusion must be performed only by trained personnel in a NICU with full monitoring and resuscitation capabilities 1

Common Pitfalls to Avoid

• Never subtract direct bilirubin from total bilirubin when making treatment decisions, unless direct bilirubin is ≥50% of total (which requires specialist consultation) 1
• Do not obtain a venous sample to "confirm" an elevated capillary TSB—this delays treatment initiation 1
• Do not rely on visual assessment of jaundice alone—objective measurement is mandatory 1
• Remember that G6PD levels can be falsely elevated during active hemolysis, so a normal level does not exclude deficiency; repeat at 3 months if strongly suspected 1

Discontinuation of Phototherapy

Stop phototherapy when TSB falls below 13-14 mg/dL. 1

Post-phototherapy follow-up:

• High-risk infants (hemolytic disease, phototherapy started <48 hours, gestational age <38 weeks): Check TSB 8-12 hours after cessation, then again the next day 1
• Standard-risk infants: Check TSB within 1-2 days after discontinuation 1