The Predictive Power of Concurrent Pulse Oximetry Readings in the Detection of Congenital Heart Defects in Newborns of the Hospital of Specialties of Children and Woman in Queretaro, Mexico

Abstract

In Mexico, CHD incidence is estimated at 18,000-21,000 newborns per year, and at least 25% will have critical congenital heart disease (CCHD). The mortality rates showed that 24% of the infant deaths in 2013 were attributable to CCHDs. Despite these, the CCHD screening is not performed in all hospitals. The general objective is to show the statistical relationships, compared with existing evidence of the power of repeat screenings on detection of CCHD, to better inform government recommendations for universal screening in Mexico. Three thousand seven pulse oximetry readings were performed on newborns (the 5th of February - the 1st of July of 2019). We aimed to perform the first screen on the subjects between 5-48 hrs of life. Some required a repeat reading due to a failure in the first. Screenings occurred between 6-69 hrs, with a mean time of 22 hrs post-delivery. Secondary readings were performed on 160, of which 29 were also given echocardiograms because they failed the secondary test. The average measurement on the foot was 93.8% and on the right hand was 93.5%. In the 29 subjects with repeated readings, seven were positive for CCHD; two were false positives. The data and analysis show promise in the association between early readings and the detection of potential CCHD. There is a correlation between the concerning readings and detection of CCHD through an echocardiogram. More data is needed to ascertain other relationships, but the results thus far imply low pulse oximetry readings associated with CCHDs and other secondary conditions associated with hypoxemia.