Clinical Guidelines (Nursing)

Newborn Screening Test

  • Introduction

    Newborn screening testing commenced in Victoria in 1966, when screening was introduced for Phenylketonuria.  Since then, screening has expanded to testing for Congenital Hypothyroidism, Cystic Fibrosis, and over 20 rare conditions.  These tests ensure early detection and treatment of these conditions.

    Aim

    This guideline provides an outline for medical and nursing staff to perform screening tests for newborn infants at the Royal Children's Hospital.

    Definition of Terms

    • Congenital Hypothyroidism
      Usually caused by an absence or improper functioning of the thyroid gland, resulting in reduced production of the thyroid hormone, thyroxine. Lack of this hormone leads to severe intellectual disability, deafness and growth problems. If detected early and treated with daily thyroxine supplements, the infant can grow and develop normally.
    • Cystic Fibrosis (CF)
      An inherited autosomal recessive condition. The mucous in the lungs and digestive system is thick and sticky resulting in respiratory infections and difficulties in digesting food properly. Early detection and treatment improves the health of the infant.
    • Phenylketonuria
      An inherited autosomal recessive condition. It is caused by an enzyme deficiency (phenylalanine hydroxylase) which results in the inability to convert phenylalanine to tyrosine. High levels of phenylalanine in the blood and tissues can damage the brain.  If not identified and treated soon after birth, severe, progressive intellectual disability results. This condition can be treated with a diet low in phenylalanine which results in normal growth and development.

    Timing of the Test

    All newborn infants are screened regardless of gestational age, weight, feeding or health status between 48 and 72 hours of life

    Palliated infants: A sample should still be obtained on palliated infants. This may help to exclude diseases which may have implications for the family in future pregnancies.  If the sample is taken after the infant dies, write in red on the screening card that it is a "post-mortem" or “peri-mortem” sample as there is a marked difference in the metabolic profile between a live and a deceased infant. 
    In certain circumstances further screening is required:

    • For infants receiving blood products (blood/exchange transfusions, platelets, fresh frozen plasma, and albumin) within the 1st 48 hours of life, a sample should be obtained if possible prior to the transfusion (even if less than 48 hours of age).  Collect a 2nd sample at least 48 hours after the transfusion when the biochemistry is more stable.  Some infants will still be receiving transfusions when the repeat sample is due. In this situation it is acceptable to delay collection of the repeat sample until the baby has 48 hours clear of transfusion of blood products. A 3rd sample is also required at three weeks post the last blood product transfusion.
    • For infants born after "in-utero blood transfusion" obtain a sample 48 to 72 hours after birth.  This is when the mother's/donor’s influence on metabolites has ceased.  Repeat the sample again 3 weeks later.
    • For very low birth weight infant, a 2nd sample should be repeated after the initial specimen to detect those infants where immaturity of the hypothalamic-pituitary-thyroid axis may initially mask primary congenital hypothyroidism. 
      • Birth weight < 1000 grams: 2nd specimen collected at 3 weeks 
      • Birth weight < 1500 grams: 2nd specimen collected at 2 weeks


    Blood Sampling Table

    Sample

    Patient Group

    Timeframe

     1st Sample

    All infants (including palliative infants)  

     48 - 72 hours

     2nd Sample

    Infants who have received blood transfusions/exchange transfusions, platelets, FFP, albumin, within the 1st 48-72 hours of life i.e. before first Newborn Screen Test is completed

    Obtain sample pre-transfusion (even if < 48 hours of age)
    If 1st Newborn Screen Test is completed < 48 hours, then need to collect 2nd sample > 48 hours post last blood product -  and need to obtain 3rd sample  


     2nd Sample

    Birth weight < 1000 grams

    3 weeks (however if blood transfusion received after first sample, obtain repeat sample when there is a 3 week gap after receiving blood product) **

     2nd Sample

    Birth weight < 1500 grams

    2 weeks (however if blood transfusion received after first sample, obtain repeat sample when there is a 3 week gap after receiving blood product) **

     3rd Sample

    Infants who have had transfusion of blood products within the 1st 48-72 hours of life (before first Newborn Screen Test is completed)

    3 weeks post last blood product **


    ** If collection is delayed due to the infant receiving multiple transfusions, it is acceptable to delay repeat sample, however do not delay repeat collection for too long:
    Birth weight < 1000 grams: repeat sample no later than 6 weeks
    Birth weight 1000 grams-1500 grams: repeat sample no later than 4 weeks 


    If in doubt or you have any queries, contact the Newborn Screening Laboratory: extension 16272

    Responsibility

    • Nursing staff need to obtain written informed consent from a parent/guardian prior to performing the test.  
    • Parent information leaflet (Newborn Screening for the Health of your Baby) informs parents about the screening program and should be given to the parents and discussed prior to obtaining written consent. An interpreter may also be required if their language not available on the website.
    • The brochure, and the simplified version in 12 other languages is available on the Newborn Screening website (www.vcgs.org.au/pathology/nbs). The information leaflet can also be obtained from VCGS (Victoria Clinical Genetic Service), 4th Floor East, Royal Children's Hospital.  
    • As part of the consent parents are required to tick the appropriate boxes:
      • Newborn Screening Consent Yes/No 
      • Secondary Research Use Yes/No 
    • The parent/guardian should sign the “Parent Signature” line on the newborn screen card
    • If further samples are needed verbal consent is acceptable and should be obtained each time and documented accordingly.
    • Nursing staff on each shift are responsible for checking that screening is performed or has been performed on infants in their care.  
    • Ensure all details are filled out correctly on the newborn screening card. 
    • If the infant has received any blood products, this needs to be noted in the Relevant Clinical / Family History section on the newborn screen car
    • Ensure all documentation has been filled out correctly (refer to 'Documentation' section of this guideline).
    • Note: if parent/guardian not available due to transfer writing “verbal consent by phone” is acceptable with explanation as to why no parent/guardian signature obtainable.


    Refusal of Consent

    If parents refuse to have the test the following steps should be followed:

    • Confirm the parents/guardian have received the Newborn Screening information brochure (“Newborn Screening for the Health of your Baby”), and that staff have discussed the test with them.
    • A medical staff member of the treating team must then meet with the parents and clearly outline the benefits of the newborn screening test and the risks of not having it done. This is to ensure the parents have a good understanding of the possible consequences.
    • Medical staff should document clearly in the Progress Notes refusal of consent and the nature of the discussion. The refusal for consent form should be completed and countersigned by the parents
    • Parents/guardian must be offered the opportunity to meet with a newborn screening counsellor (VCGS ext.16200).  Contact the newborn screening counsellor as soon as possible.
    • The newborn screening card should be filled out with relevant infant details and "REFUSAL" written in red across the card. The parents need to sign and tick that they refuse to consent to the screening test, and this card should be sent to the laboratory without the sample taken. 
    • Document the refusal for the test in Child Health Record Book.
    • Inform the parents/guardian that if the infant becomes unwell, they should inform their GP/paediatrician that their infant has not had a newborn screening test.
    • Parents/guardian can change their mind at any stage but it should be explained to them that some disorders will not be detected if newborn screening is not performed at the correct time. 


    Sampling

    • Collect newborn screening card and equipment for capillary blood sampling. Refer to RCH Procedure “Collection of Capillary Blood Samples” if require
    • Refer to RCH Policy Aseptic Technique and adhere to Standard Aseptic Technique principles for this procedure
    • Refer to Clinical Practice Guidelines regarding the use of  Sucrose (oral) for procedural pain management in infants
    • Fill in the details of the infant on the card before collecting the blood. 
    • Obtain written informed consent
    • Capillary blood sampling from the heel is the preferred method for sampling, ensure that the limb chosen has adequate perfusion.  
    • For arterial line sampling, use a non-heparinised syringe to collect blood. . It is important that the sample is not diluted with the infusion fluid. If using an arterial line, draw back 2-3 ml of blood, change syringe and collect sample; return the first 2-3 ml of blood. 
    • Fill a minimum of 3 circles 2/3 full with a large drop of blood from the back of the screening card ensuring sufficient blood has soaked through both sides. 
    • Air dry the card without the use of heat (approx. 4 hours) and place in hospital envelope, not a plastic specimen bag. 
    • Send the envelope to the Newborn Screening Laboratory, 4th Floor East via the RCH core lab

      Points to consider related to sampling technique

      • Do not squeeze or milk the infant's heel. This will contaminate the specimen with tissue fluids and cause excessive pain
      • Do not apply paraffin to a heel
      • Wipe away the first drop of blood (to remove contaminants)
      • Do not overlay the blood spots on the card. This causes layering and therefore too much blood in the test disc. 
      • Only soak blood from the back of the screening card.
      • The card should not be rubbed on the heel and the blood spots should not be pressed with fingers.  This abrades or compresses the card and reduces its blood holding capacity.
      • Small misalignments with the circles or slight over or under filling of the circles is acceptable, because the entire bottom strip of the test paper contains the specialized filter paper (and not just the four circles)
      • Blood spots on the card should only be air dried at room temperature.
      • Avoid the card coming into contact with contaminated skin or surfaces. (Placing the card on a surface which has been in contact with a wet nappy may be sufficient to produce a false positive test for cystic fibrosis.)
      • For further information on sampling, refer to VCGS Newborn Screening Collection Guidelines

      Documentation

      • Record on the card relevant clinical information including if the infant is on TPN, transfusions, or is deceased
      • Record date and time of sample taken in: 
        • Electronic Medical Record:
          • Progress Notes
        • Child Health Record book 
      • For Butterfly Ward patients the following additional documentation is required in the: 
      • Electronic Medical Record:
        • ADT Navigators: Admission: Admission Information 
        • Flowsheets:  NICU Shift Checks: Neonatal Screening Tests
      • Admission Book 

      Special Considerations
      Parents/guardian may request to have their infant's newborn screening card returned to them after two years.  For further information, contact the Newborn Screening Laboratory or visit the website.
      Occasionally, stored newborn screening cards get used for research. Some examples are the development of new tests or determining normal levels of a biomarker. This research is de-identified (i.e. no personal details are released to the researchers) and must be approved by an ethics committee. Parents can tick the “No Secondary Research Use” box if they do not wish their child’s card to be available for such research.


      Links

      Other Resources

       

      Newborn Screening Laboratory
      Victorian Clinical Genetic Services
      Royal Children's Hospital, Parkville 3052
      Tel: (03) 8341 6272 Fax: (03) 8341 6398
      Newborn Screening nurse:
      Phone: 83416460

       

      Evidence Table

       Newborn Screening Evidence Table

      Please remember to read the disclaimer.


      The revision of this clinical guideline was coordinated by Sharlene Patti, Clinical Nurse Educator, Butterfly Ward. Approved by the Clinical Effectiveness Committee. Authorised by Bernadette Twomey, Executive Director Nursing Services. Current as of August 2016.