Perfusion index as a diagnostic tool for patent ductus arteriosus in preterm infants.
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.


CONCLUSIONS
The pre- and postductal PI differences were significantly related to the hemodynamic changes of PDA and might be useful to detect hemodynamically significant PDA.
Department of Paediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Anant
A
Khositseth
Natthachai
N
Muangyod
Pracha
P
Nuntnarumit
D003430:Cross-Sectional Studies; D004374:Ductus Arteriosus, Patent / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004452:Echocardiography; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D008297:Male; D011237:Predictive Value of Tests; D011673:Pulsatile Flow / Q000502:physiology*; D012039:Regional Blood Flow / Q000502:physiology; D012680:Sensitivity and Specificity