Pulse Oximetry a Non-Invasive Screening Test to Intensify Primary Diagnosis of Critical Cyanotic Congenital Heart Disease in Neonates- A Retrospective Study.

ABSTRACT

Pulse oximetry is an important screening technique to intensify timely diagnosis of critical cyanotic congenital heart disease in neonates which is a noninvasive, safe and an easy method. It is a highly specific test having low false positive rates. This screening test was conducted in Department of Pediatrics, Darbhanga Medical College & Hospital, Laheriasarai, Darbhanga, Bihar, between 24 hours and 36 hours after birth, with use of the right hand of infants and either foot to diminish false positive results.METHODSData for study has been collected from birth records from Darbhanga Medical College & Hospital, Bihar, and included- 1. saturation level from either feet and right hand for the primary and further recurrence of screening. 2. outcomes of the echocardiographic test findings. 3. important non-cardiac illness diagnosed at the hospitalization for infants which failed screening for cyanotic CHD. For the correction of errors related to data of the study, we satisfied autonomous investigations of pulse oximetry requiring AAP CCHD screening algorithm to identify infants to pass with a saturation ≥95% in hand or either foot and a ≤3% difference and those falling after finishing 3 transitional screening tests. After three consecutive measurements, there is difference of SpO2 of more than 3% between pre-ductal and post-ductal SpO2.RESULTSThe combination of pulse oximetry and physical examination improved the sensitivity to up to 57.14% with a specificity of 99.73%. The overall mortality rate of CCHD was 36.8% [7 out of 19]. The mortality rate of early detection were 37.5% [6 out of 16]. Late detection of CCHD has mortality rate of 33.3% [1 out of 3]. 123 [13.1%] and 70 [7.4%] newborns have either foot or right hand SpO2 level < 95% among 941 study newborns at the time of the initial screening. The mean SpO2 level of either feet and right arm of study newborns were 95.8% [SD 2.3] and 96.0% [SD 2.2] respectively. Either feet and right arm level of SpO2 <95% and either feet to right arm level of SpO2 difference of >3% among 142 [15.1%] study newborns.CONCLUSIONSPulse oximetry screening for primary diagnosis of critical cyanotic CHD is an easy, economical and non-invasive test which covers the essential criteria in addition to worldwide newborn screening panel. Extensive approval and implementation can considerably reduce the morbidity in newborns infants and is likely to be an additional important tool in low resource settings where most of newborn infants are born without prenatal diagnosis. Although, this study showed reduced sensitivity of pulse oximetry for critical cyanotic CHD nearly <50%.