Perfusion Index as a Predictor of Hemodynamically Significant Patent Ductus Arteriosus in Preterm Newborns

Aim: To assess the value of perfusion index (PI) and arrive at the ideal cut-off value of delta PI (DPI) (pre and postductal difference in PI) in identifying hemodynamically significant patent ductus arteriosus (HsPDA). Methods: Prospective observational study was conducted on 156 preterm newborns of <37 weeks in the NICU of tertiary care center, from August 2019 to March 2020 after ethical clearance. 156 preterm babies were classified into noPDA, HsPDA and Non-HsPDA based on echocardiogram findings and compared with DPI value on Day 1 to 3 of life. Receiver operating characteristic (ROC) curve was constructed to establish cut-offs for DPI in diagnosing HsPDA. A P value <.05 is considered for statistical significance. Results: There was a significantly lower PI in both preductal and post ductal limbs with HsPDA compared to other groups. A DPI Cut-off of 0.75 on day 2 of life has a sensitivity of 75%, specificity of 100% and positive predictive value (PPV) of 100% and a negative predictive value of 89%. Conclusion: PI is a simple non-invasive bedside index predict the presence of a HsPDA in preterm newborns and DPI of >0.75 indicates for presence of HsPDA.