Clinical Guidelines (Nursing)

Newborn Screening Test

    1. Introduction
    2. Aim
    3. Definition of Terms
    4. Timing of the Test
    5. Responsibility
    6. Refusal of Consent
    7. Sampling
    8. Documentation
    9. Special Considerations
    10. Links
    11. Other Resources
    12. Evidence table

    Introduction

    Newborn screening tests commenced in Victoria in 1966, when screening was 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: Is a condition 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): Is 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: Is 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 and/or medication which promotes normal growth and development.

    Timing of the Test

    All newborn infants are screened regardless of gestational age, weight, feeding or health status between 48 - 72 hours of life. 
    In certain circumstances further screening may be required including the following:
    • For infants who are commencing Total Parenteral Nutrition (TPN), take initial sample preferably prior to starting the TPN, even if the infant is less than 48 hours of age. This is important as TPN can sometimes cause abnormal newborn screening results. Mark "TPN" box on screening card and repeat the sample 48 hours after cessation of TPN. 
    • It is important to obtain a sample 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" sample as there is a marked difference in the metabolic profile between a live and a deceased infant. 
    • For infants receiving the following blood products; blood/exchange transfusions, platelets, fresh frozen plasma (FFP), albumin, a sample should be obtained if possible prior to the transfusion.  Collect a 2nd sample at least 48 hours after the transfusion when biochemistry is stable.  A 3rd sample is collected three weeks later as the genetic profile will be stabilised. 
    Please record any transfusion or TPN details on the card 

    • For infants born after "in-utero blood transfusion" obtain a sample 48-72 hours after birth.  This is when the mother's/donor's influence on metabolites has ceased.  Repeat the sample again 3 weeks later. 
    • For extremely low birth weight or premature infants 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
    Please note: Some babies will still be on TPN or receiving transfusions when the repeat sample should be taken. In this situation it is acceptable to delay collection of the repeat sample for a while until the baby has 48 hours clear of TPN or transfusion of blood products.
    However, please do not delay the repeat collection for too long:
    Birth weight <1000 grams: repeat sample no later than 6 weeks
    Birth weight <1500 grams: repeat sample no later than 4 weeks 

     

    Blood Sampling Table

    Sample

    Patient Group

    Timeframe

     1st Sample

    All infants (including palliative or deceased infants)  

     48 - 72 hours

     2nd Sample

    Infants who have received blood transfusions/exchange transfusion/s, platelets, FFP, albumin, from birth to 72 hours of life 

    Obtain sample pre-transfusion (even < 48 hours of age), then > 48 hours post transfusion - NB: need to obtain 3rd sample  

     2nd Sample

    Infants on Total Parenteral Nutrition (TPN)

    48 hours post cessation of TPN

     2nd Sample

    Premature infants birth weight < 1000 grams

    3 weeks

    2nd Sample

    Premature infants birth weight < 1500 grams

    2 weeks

     3rd Sample

    Infants who have had transfusions of blood within the 1st 48-72 hours of life

    3 weeks post transfusion

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

    Responsibility

    • Nursing staff need to obtain written informed consent from a parent 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. 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 should sign the "Parent Signature" line on the newborn screen card. Parent consent should also be documented on the patient's inpatient progress notes.
    • 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 card
    • Ensure all documentation has been filled out correctly (refer to 'Documentation' section of this guideline). 

    Refusal of Consent

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

    • Confirm the parents have received the Newborn Screening Program 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 inpatient progress notes refusal of consent and the nature of the discussion. The refusal for consent format  should be overprinted on the inpatient progress notes and the parents/guardians must countersign the entry.
    • Parents must be offered the opportunity to meet with a newborn screening counsellor (VCGS ext.16200) if they wish.  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 and sent to the Newborn Screening Laboratory.
    • Document the refusal for the test in Child Health Record Book. 
    • Advise the parents that in the event that the infant becomes unwell, they should inform their GP/paediatrician that their infant has not had a newborn screening test. 
    • Parents 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 required
    • 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.  Arterial line sampling for the newborn screeni     ng test should only be used as a 'last resort'
    • 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. 

    Points to consider related to sampling technique

    • It is important not to squeeze or milk the infant's heel. This will contaminate the specimen with tissue fluids and cause excessive pain
    • Blood spots should not be overlaid on the card. This causes caking 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 invariably abrades or compresses the card and reduces its blood holding capacity. 
    • 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.) 

    Documentation

    • Record date and time of sample taken in: 
      • Child Health Record book 
      • Patient's medical record on the inpatient progress notes 
    • For Butterfly Ward patients the following additional documentation is required: 
      • Neonatal Nursing Admission/History Form. This includes circling "Yes" when consent is obtained
      • NICU Checklist
      • Admission Book 
      • Neonatal Screen Checklist (included with admission paperwork and remains at patient's bedside) 
    Special Considerations
    Parents 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 development of this clinical guideline was coordinated by Chris Lim, Registered Nurse, Butterfly Ward. Approved by the Clinical Effectiveness Committee. Authorised by Bernadette Twomey, Executive Director Nursing Services. Current as of August 2013.