Perfusion Index as a Diagnostic Tool for Patent Ductus Arteriosus in Preterm Infants

Abstract

Background: Perfusion index (PI) could reflect peripheral flow. Preterm infants with hemodynamically significant patent ductus arteriosus (hsPDA) will have left-to-right shunt across PDA causing less blood flow to the lower legs. Objective: To evaluate pre- and postductal PI differences (ΔPI) in hsPDA. Methods: Preterm infants with gestational age <34 weeks were assessed for ΔPI on days 1, 3, and 7 of life with simultaneous echocardiography. Based on echocardiography, each infant was categorized into hsPDA, non-hsPDA, and no PDA. Results: Thirty infants (16 males), median age 31 weeks (interquartile range, IQR, 29-32) and weight 1,490 g (IQR 1,100-1,670) were enrolled. On days 1 and 3 of life, the ΔPI of infants with hsPDA (1.57%, IQR 0.28-2.32, n = 14, and 1.32%, IQR 0.28-1.83, n = 10) were significantly higher than those without hsPDA (0.14%, IQR -0.03 to 0.30, n = 16, and 0.08%, IQR -0.07 to 0.26, n = 20), p = 0.009 and 0.005, respectively. At all time points (days 1, 3, and 7 of life, n = 84), ΔPI >1.05% had sensitivity, specificity, positive predictive value, and negative predictive value of 66.7, 100, 100, and 86.4%, respectively, to detect hsPDA. Conclusion: The pre- and postductal PI differences were significantly related to the hemodynamic changes of PDA and might be useful to detect hemodynamically significant PDA.

Perfusion Index in Preterm Infants during the First 3 Days of Life: Reference Values and Relation with Clinical Variables

“…In the current study, there was a positive association with PI during the first 24 h and from 37 h onwards (when taking into account the hsPDA × time interaction) as also found by others [20]. One might expect a decrease in (peripheral) perfusion due to the ductal steal phenomenon and thereby a decrease in PI.…”

“…Earlier studies have shown conflicting results concerning the effect of hsPDA on PI [20,21]. In the current study, there was a positive association with PI during the first 24 h and from 37 h onwards (when taking into account the hsPDA × time interaction) as also found by others [20].…”

Management of Patent Ductus Arteriosus in Premature Infants

“…These investigators concluded that in the presence of clinical signs of PDA and a delta PI of >1.05 %, the diagnosis of hsPDA should be considered. This test may be of special value in resource poor countries where echocardiography is not readily available [24]. Further studies are needed to confirm this finding.…”

Diagnosis and Management of Patent Ductus Arteriosus

“…Various approaches include interpretation of pulse oximetry information (perfusion index, plethysmography), (19)(20)(21) interpretation of transthoracic electrical signals (impedance, cardiometry, velocimetry, bioreactance), (22)(23)(24)(25) regional oxygenation (near-infrared spectroscopy), (26) alterations in skin microcirculation (side stream dark-field imaging, reflectance spectrophotometry), (27)(28) resonance Raman spectroscopy (Lauren J. Ruoss, personal communication, May 2018), and others.…”