Impact of pulse oximetry screening to detect congenital heart defects: 5 years’ experience in a UK regional neonatal unit

Abstract

Pulse oximetry screening (POS) has been shown to be an effective, non-invasive investigation that can detect up to 50–70% of previously undiagnosed congenital heart defects (CHDs). The aims of this study were to assess the accuracy of POS in detection of CHDs and its impact on clinical practice. All eligible newborn infants born between 1 Jan 2015 and 31 Dec 2019 in a busy regional neonatal unit were included in this prospective observational study. A positive POS was classified as two separate measurements of oxygen saturation < 95%, or a difference of > 2% between pre- and post-ductal circulations. Overall, 23,614 infants had documented POS results. One hundred eighty nine (0.8%) infants had a true positive result: 6 had critical CHDs, 9 serious or significant CHDs, and a further 156/189 (83%) infants had significant non-cardiac conditions. Forty-three infants who had a normal POS were later diagnosed with the following categories of CHDs post-hospital discharge: 1 critical, 15 serious, 20 significant and 7 non-significant CHDs. POS sensitivity for detection of critical CHD was 85.7%, whereas sensitivity was only 33% for detection of major CHDs (critical and serious) needing surgery during infancy; specificity was 99.3%.Conclusion: Pulse oximetry screening showed moderate to high sensitivity in detection of undiagnosed critical CHDs; however, it failed to detect two-third of major CHDs. Our study further emphasises the significance of adopting routine POS to detect critical CHDs in the clinical practice. However, it also highlights the need to develop new, innovative methods, such as perfusion index, to detect other major CHDs missed by current screening tools. What is Known:• Pulse oximetry screening is cost effective, acceptable, easy to perform and has moderate sensitivity and high specificity in detection of critical congenital heart defects.• Pulse oximetry screening has been implemented many countries including USA for detection of critical congenital heart defects, but it is not currently recommended by the UK National Screening Committee. What is New:• To our knowledge, this is the first study describing postnatal detection and presentation of all the infants with congenital heart defects over a period of 5 years, including those not detected on the pulse oximetry screening, on the clinical practice. • It emphasises that further research required to detect critical congenital heart defects and other major CHDs which can be missed on the screening tools currently employed in clinical practice.

Major congenital heart defects are rarely diagnosed after newborns' hospital discharge with modern screening

“…Due to foetal and newborn screening, our study did not reveal a higher proportion of CHDs in infants than in other age groups, contrary to other studies 16,17 . However, the screening system does not detect all heart defects 18,19 . The physiologic changes in neonates' circulatory systems, such as the closure of PDA and the decline of pulmonary vascular resistance, cause some CHDs (e.g.…”

“…16,17 However, the screening system does not detect all heart defects. 18,19 The physiologic changes in neonates' circulatory systems, such as the closure of PDA and the decline of pulmonary vascular resistance, cause some CHDs (e.g. CoA and VSD) to be diagnosed later, as was seen in our study in patients who came to the emergency room due to symptoms.…”

Pulse oximetry test for screening congenital heart diseases: a systematic review

“…Furthermore, the nurse is committed to informing and guiding those responsible for the newborn about neonatal screening, an action that will have a direct impact on its effectiveness. Furthermore, with this proximity to the clientele and guidance, the nurse promotes the reduction of family members' anxiety regarding suspected or positive cases (5,8,11,57) .…”

Neonatal Pulse Oximetry Screening for Congenital Heart Disease

“…Between 1999 and 2006, the number of child deaths in the US reported as a result of congenital cardiac abnormalities exceeded 13,000 [7]. Due to the paucity of CHD screening programs, a sizable fraction of neonates with CCHDs go undiagnosed before being released from the hospital [8]. Only around half of all CHDs can be detected by foetal anomaly screening using prenatal ultrasonography at 20 weeks [9].…”