Neonatal pulse-oximetry screening for duct-dependent congenital heart disease
Up to two per 1,000 babies born alive have a duct-dependent circulation. In the United Kingdom, 30% of babies with critical heart disease leave hospital with the disease undetected. Now researchers in Sweden have reported the results of neonatal pulse-oximetry screening.
A total of 39,821 apparently well babies were screened before hospital discharge in the region of West Götaland between 1 July 2004 and 31 March 2007. A new-generation pulse oximeter was used to measure oxygen saturation on the palm of the right hand (preductal) and on either foot (postductal). Screening was considered positive when repeated measurement showed oxygen saturation <95% at both sites or a difference of 3% or greater between the two sites. Physical examination, pulse oximetry and both examinations gave a sensitivity of 63%, 62% and 83%; specificity of 98%, 100% and 98%; positive predictive value of 1.4%, 20.7% and 2.9%; and negative predictive value of over 99% with all three. False-positive rates were 1.9%, 0.17% and 2.09%, and numbers of true positives, 10, 18 and 24. Five cases were missed, all with aortic arch obstruction. Echocardiography in oximetry-positive cases was normal in 2.3 cases for every true-positive case. The risk of leaving hospital with undiagnosed duct-dependent circulation was 8% in West Götaland and 28% in regions not using pulse-oximetry screening.
Pulse-oximetry screening detected most cases of duct-dependent circulation (92%). Screening was cost-neutral, but it is anticipated that it will become cost-effective.
De-Wahl Granelli A, et al. Impact of pulse oximetry screening on detection of duct dependent congenital heart disease: a Swedish prospective screening study in 39,821 newborns. BMJ 2009;338:145– 149; Barrington KJ. Neonatal screening for life threatening congenital heart disease. Ibid:117–118 (editorial).