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Published on: January 27, 2023
Perfusion index as a diagnostic tool for patent ductus arteriosus in preterm infants
Anant Khositseth1, Natthachai Muangyod, Pracha Nuntnarumit
1Department of Paediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Insights
Perfusion index differences (ΔPI) can help detect hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants. A ΔPI greater than 1.05% shows high accuracy in identifying hsPDA.
Area of Science:
- Neonatal physiology
- Cardiovascular monitoring
- Perinatal medicine
Background:
- Perfusion index (PI) reflects peripheral circulation.
- Hemodynamically significant patent ductus arteriosus (hsPDA) in preterm infants causes reduced lower body blood flow due to left-to-right shunting.
Purpose of the Study:
- To assess the difference between pre- and postductal PI (ΔPI) in preterm infants with hsPDA.
- To determine the utility of ΔPI in diagnosing hsPDA.
Main Methods:
- Preterm infants (<34 weeks gestational age) were monitored for ΔPI on days 1, 3, and 7 postpartum.
- Echocardiography was used to categorize infants into hsPDA, non-hsPDA, or no PDA groups.
- Simultaneous PI measurements and echocardiography were performed.
Main Results:
- Infants with hsPDA showed significantly higher ΔPI on days 1 and 3 compared to those without hsPDA (p=0.009 and p=0.005).
- A ΔPI threshold of >1.05% demonstrated 66.7% sensitivity and 100% specificity for detecting hsPDA.
- Positive and negative predictive values for ΔPI >1.05% were 100% and 86.4%, respectively.
Conclusions:
- ΔPI is significantly associated with the hemodynamic effects of PDA.
- Pre- and postductal PI difference is a potentially valuable, non-invasive tool for detecting hsPDA in preterm neonates.
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.
