Pulse oximetry findings in newborns with antenatally diagnosed congenital heart disease

A retrospective review of admission preductal oxygen saturations of neonates with antenatally diagnosed critical congenital heart disease (CCHD) was performed to investigate the differences in newborn pulse oximetry (Pulsox) by specific CCHD diagnosis. Saturations were recorded at median of < 1 h (range < 1–9 h) after delivery. Data was stratified by CCHD diagnosis and analysed according to the three different admission Pulsox thresholds, ≤ 90, ≤ 92 and ≤ 95%. Of the 276 neonates studied, 208 were clinically well at admission, with no co-morbidities, gestation > 34 weeks and birth weight > 1.8 kg. A statistically significant increase in the proportion with low admission saturations was seen using ≤ 95% saturation threshold (72% (95% CI 66–78)) compared to ≤ 92% (52% (95% CI 46–59)) and ≤ 90% (46% (95% CI 39–52)). Sub-group analysis found the proportion of neonates with low saturations varied according to the specific CCHD diagnosis with only 20–42% of neonates with aortic stenosis, coarctation of the aorta and pulmonary stenosis having saturations ≤ 95%. Conclusion: The proportion of neonates with low admission oxygen saturation varied by CCHD diagnosis with those without critically reduced pulmonary blood flow not having low admission saturations, in general, even using the ≤ 95% threshold which had the highest proportions of abnormal saturations. This data may assist developing Pulsox screening policies.What is Known:• The addition of pulse oximetry (Pulsox) screening to the routine newborn examination increases the sensitivity of CCHD detection. Pulsox screening is also highly specific for CCHD in asymptomatic neonates, with low false-positive rates.• Early diagnosis of CCHD improves patient outcomes in relation to both morbidity and mortality.What is New:• The proportion of affected infants with an abnormal Pulsox result varies by CCHD diagnosis and screening threshold. In our study using the ≤ 95% threshold gave the highest proportion of neonates with abnormal saturations at admission.• In general, Pulsox yield of abnormal results is low for CCHD diagnoses not associated with critically reduced pulmonary blood flow; however, increasing the Pulsox threshold increased the proportion of infants with an abnormal result.