Perfusion index in newborns during critical congenital heart disease screening at 24 hours in healthy newborns: retrospective observational study from the United States

Objective: To describe the distribution of Perfusion Index (PI) in asymptomatic newborns at 24 hours of life when screening for Critical Congenital Heart Disease (CCHD) using an automated data selection method.
Design: This is a retrospective observational study.
Setting: Newborn nursery in a California public hospital with 3500 to 4000 deliveries annually.
Methods: We developed an automated program to select the PI values from CCHD screens. Included were term and late preterm infants who were screened for CCHD from November 2013 to January 2014 and from May 2015 to July 2015. PI measurements were downloaded every 2 seconds from the pulse oximeter and median PI were calculated for each oxygen saturation screen in our cohort.
Results: We included data from 2768 oxygen saturation screens. Each screen had a median of 29 data points (interquartile range 17 to 49). The median PI in our study cohort was 1.8 (95% confidence interval 1.8 to 1.9) with interquartile range 1.2 to 2.7. The medi...