The Role of Perfusion Index in Pulse Oximetry for the Assessment of Hemodynamic Instability in Preterm Infants

Adhi Teguh Perma Iskandar, Yuniasti Evitasari, Nastiti Kaswandani, Nia Kurniati, Fabiola Cathleen

Abstract

Background and Aim: The perfusion index, derived from continuous pulse oximetry, may be useful for monitoring peripheral perfusion.

Materials and Methods: This prospective observational study was conducted on preterm infants with gestational ages of 25 to < 37 weeks presenting with respiratory distress during the first 72 hours of life at Cipto Mangunkusumo Hospital, Jakarta, Indonesia.

Results and Discussion: Subjects with low cardiac output had significantly lower perfusion index than those with normal or high cardiac output. The perfusion index cutoff values to detect low cardiac output were < 0.65% on day 1 (54.54% sensitivity, 53.95% specificity, 14.63% positive predictive value [PPV], 89.13% negative predictive value [NPV]), < 0.49% on day 2 (54.54% sensitivity, 86.84% specificity, 37.5% PPV, 92.96% NPV), and < 0.55% on day 3 (54.54% sensitivity, 84.21% specificity, 33.3% PPV, 92.75% NPV). The perfusion index cutoff values to detect high cardiac output were < 0.67% on day 3 (57.14% sensitivity, 61.25% specificity, 11.76% PPV, 94.23% NPV).

Conclusion: The perfusion index shows low sensitivity but high specificity and NPV in evaluating hemodynamic instability in preterm infants.