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Timing and Exceptions

Timing of the screen

  • The recommended window for CCHD screening is 24- 48 hours of age, with an optimal window of 24-36 hours of age.
  • Screens performed prior to 24 hours of age have been shown to demonstrate a higher false positive rate than screens performed after 24 hours because transitional cardiovascular changes that occur during the initial hours of life may be incomplete (closure of the ductus arteriosus).
  • Screening may occur after the recommended window of 24-48 hours for NICU/SCN babies, if clinically appropriate (normal vital signs, no ventilation support, no supplemental oxygen) up to 7 days of age. As the majority of CCHD will present prior to 7 days of age, there is little value to screening after this time.


Infants admitted to a NICU

  • Infants admitted to the NICU/SCN/PICU and discharged home before 7 days of age will have CCHD pulse oximetry screening completed during their hospitalization when appropriate (no respiratory distress or cardiac symptoms) OR at the time of discharge.
  • Infants admitted to NICU/SCN/PICU and discharged home after 7 days of age who have not had CCHD screening completed will not undergo CCHD screening at discharge.

Early discharge (less than 24 hours)

  • Infants that are discharged home from hospital prior to 24 hours of age are considered to be discharged early.
  • They will not have a CCHD pulse oximetry screen prior to discharge, but will either have the screen performed by their midwife on an outpatient basis (in their home) during the recommended time of 24-48 hours of age, or return to the hospital or other care facility for a CCHD pulse oximetry screen when the infant is 24-48 hours of age.
  • It is the responsibility of the discharging hospital to arrange the CCHD screen. Organizations should develop their own internal process to handle these cases.

Prenatal diagnosis or diagnosis during initial 24 hours

  • Infants that have a prenatal diagnosis of a CHD or have been diagnosed during their initial 24 hours with a CHD will not undergo a CCHD pulse oximetry screen.

Infants transferred to another hospital

  • If transfer occurs before 24 hours, or a CCHD screen was not completed during the recommended window because the infant was not stable from a cardio-respiratory perspective, this information should be included in the discharge summary.
  • Clear communication between the two hospitals is essential to ensure that the CCHD screen can be completed when and if appropriate.

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