Newborn screening test

  • Used to screen babies for rare genetic metabolic or endocrine conditions
  • A heel prick test is collected onto a special card — usually done in hospital

Do first

  • Explain and demonstrate procedure
  • If parents decline to have infant screened
    • Record reason for non-collection in baby’s medical records
    • Complete and return screening collection card. Record reason for non-collection on card

Do

Document

  • Get card from nearest hospital
  • Do not touch the circle area on card — contamination of sample may occur
  • Follow the instructions on the card. Fill out details using a black or blue pen, before starting test
    • If test is a repeat collection — write 'repeat' on card
  • Record collection (including card number) on the 'Examination of the Newborn' page on baby’s chart (if first test), and in baby’s medical records

Perform test

  • Blood ideally collected 48–72 hours after birth (still useful if collected after 72 hours)
  • Prepare equipment — screening collection card, gloves and sterile lancet (point not more than 2.4mm) cotton wool ball or gauze and  small sticking plaster
  • Wrap baby securely. Have parent hold or breastfeed baby so baby is relaxed
  • Make sure heel is pink and warm so blood flows easily — keep heel lower than body
    • If heel cold and blood won’t flow — warm the foot
    • Pressing firmly against skin before pricking may help blood flow
  • Clean heel with damp cotton wool ball and allow to dry completely
    • Test is unreliable if contaminated with water, faeces, talc and urine etc
  • Prick on inside or outside edge of heel on plantar (bottom) surface of foot, use side of heel facing down — Figure 4.1.

Figure 4.1   

Do not squeeze/milk heel — excess tissue fluid will be expelled. Let blood drip out

  • Wipe away first drop of blood
  • Let large drop of blood form. Absorb blood with filter card, the correct side is marked on the card
  • Put drop in centre of circle and allow it to spread by itself. The circle usually not filled with first drop. Put more drops in centre of circle and let the blood spread until circle completely filled — Figure 4.2
    • Do not let blood dry between drops
    • Only fill from correct side as marked on card
    • Turn card over to check circle full on both sides
    • Completely fill circle before moving to next
  • Fill other circles the same way. At least 2 circles must be completely filled

Figure 4.2   

©Victorian Clinical Genetics Services. Adapted with permission.

Dry and send card

  • Card needs to be air dried for at least 4 hours at room temperature and not more than 30°C, away from sunlight, moisture or splashes
  • Use rack or edge of bench to dry card. Stand up to let air flow to both sides
  • Put card in envelope only when totally dry
    • If more than one card being sent — pack so blood spots alternate top and bottom to reduce cross-contamination
    • Do not put card in plastic — may sweat, especially if not completely dry
    • Put envelope inside another addressed envelope
  • Mail direct to address on card as soon as possible 

Follow-up

  • Only abnormal results are reported to health clinic or carer — medical consult
  • Carers are told directly of any anomalies