Pulse Oximetry Screening for Detecting Critical Congenital Heart Disease in Neonates

Abstract

Background Congenital heart disease (CHD) leads to significant morbidity in the neonatal population and is a crucial disorder behind early infancy death rates. Most have a critical congenital heart defect (Cr CHD) out of all the heart defects found in babies. A subgroup of cardiac anomalies needs surgery or catheter intervention during the neonatal period. Pulse oximetry is a good screening tool to detect cr CHD in neonates. This study aims to assess the effectiveness of pulse oximetry as a screening tool in a rural setting. Methods This was a hospital-based prospective observational study. All consecutively born neonates whose parents consented to the study were subjected to pulse oximetry on all four limbs. Their peripheral arterial oxygen saturation was measured on days one, two, and three of life, starting four hours after birth. Babies detected with cyanotic congenital heart disease (CCHD) before birth are not a part of this study. All those with arterial oxygen saturation of less than 95% or a difference of saturation of more than 3% in the upper and lower limbs were considered suspects for Cr CHD and subjected to echocardiography. Results Among 5874 neonates studied, researchers found 164 babies to have significant hypoxemia on pulse oximetry, and 44 CHD were detected on echocardiography within the first three days of life (positive predictive value (PPV) 12.2%). The physician referred all of them to a higher center before further delay. Thirty-four babies with other congenital heart diseases were found using pulse oximetry examination. Also, 108 cases of hypoxemia due to other causes were found and monitored. Conclusion Critical congenital heart diseases are a significant cause of death among neonates and require early diagnosis and emergent medical and surgical management. They are associated with hypoxemia, and this principle can be used to screen them using a pulse oximeter.

Keywords: cyanosis; echocardiography; hypoxemia; muconium aspiration; oxygen saturation.

Figure 1. Gestational age of Cr CHD

Amongst those diagnosed as having critical congenital heart disease, five (41.67%) were < 37 weeks by gestation, and the remaining seven (58.33%) were >37 weeks. Cr CHD: Critical congenital heart disease

Figure 2. Hypoxemic infants detected on pulse oximetry

Out of 5874 neonates, 164 (2.79%) were positive for hypoxemia on pulse oximetry.

Figure 3. Positive predictive value for congenital and critical heart disease

PPV: Positive predictive value, Cr CHD: Critical congenital heart disease, CHD: Congenital heart disease

Figure 4. Images of pulse oximeters available in the market

A: Pulse oximeter marketed and manufactured by Allied Medical (Allied Medical Ltd. Gurugram, HR, India); B: Pulse oximeter marketed and manufactured by S.Cure (S.Cure Medserv Pvt. Ltd., New Delhi, India)