Accuracy of Wireless Pulse Oximeter on Preterm or <2.5 kg Infants

Area of Science:

• Neonatal care
• Biomedical engineering
• Medical device technology

Background:

• Continuous monitoring of heart rate (HR) and oxygen saturation (SpO2) is crucial for preterm infants in the neonatal intensive care unit (NICU).
• Advancements in wireless pulse oximetry offer potential benefits, but their accuracy in vulnerable preterm populations requires rigorous evaluation.
• Existing data on the accuracy of wireless devices like the Owlet Smart Sock 3 (OSS3) in preterm infants (<2.5 kg) is limited.

Purpose of the Study:

• To compare the accuracy of the wireless Owlet Smart Sock 3 (OSS3) against a standard wired Masimo SET (Masimo) pulse oximeter for monitoring HR and SpO2.
• To assess the reliability and agreement between the two devices in preterm infants or those weighing less than 2.5 kg.
• To provide evidence-based insights into the potential use of wireless pulse oximetry in neonatal monitoring.

Main Methods:

• An observational study design was employed, enrolling 28 eligible preterm infants (<2.5 kg) without significant anomalies or medical instability.
• Simultaneous HR and SpO2 measurements were collected for 60 minutes using both the OSS3 and Masimo devices.
• Data analysis included time epoch alignment, filtering for poor tracings, and statistical comparisons using Pearson's correlation, Bland-Altman analysis, average root mean square (ARMS), and prevalence and bias adjusted kappa (PABAK).

Main Results:

• Over 21 hours of data, strong correlation was found for HR (r=0.98) and positive correlation for SpO2 (r=0.71) between OSS3 and Masimo.
• The Bland-Altman analysis showed minimal bias for HR (-1.3 bpm) and SpO2 (0.3%), with limits of agreement indicating good concordance.
• The average root mean square (ARMS) for SpO2 was 2.3% in the 70-100% range, with precision decreasing at lower saturation levels. A strong agreement (PABAK=0.94) was observed for SpO2 thresholds around 90%.

Conclusions:

• The wireless Owlet Smart Sock 3 (OSS3) demonstrates comparable accuracy to the Masimo SET for monitoring heart rate and oxygen saturation in preterm infants weighing less than 2.5 kg.
• While promising, limitations such as motion artifacts, lack of arterial blood gas correlation, and limited diversity necessitate further investigation.
• Additional data, particularly in lower HR and SpO2 ranges, is recommended before widespread inpatient implementation of the OSS3 in neonatal intensive care units.