Assessment of Apple Watch Series 6 pulse oximetry and electrocardiograms in a pediatric population

Background: Recent technologic advances have resulted in increased
development and utilization of direct-to-consumer cardiac wearable devices
with various functionality. This study aimed to assess Apple Watch Series
6 (AW6) pulse oximetry and electrocardiography (ECG) in a cohort of
pediatric patients. Results: A total of 84 patients were enrolled over a
5-week period. 68 patients (81%) were placed into the SpO2 and ECG arm,
with 16 patients (19%) placed into the SpO2 only arm. Pulse oximetry data
was successfully collected in 71/84 (85%) patients and ECG data in 61/68
(90%). ΔSpO2 between modalities was 2.0±2.6% (r=0.76). ΔRR was 43±44msec
(r=0.96), ΔPR 19±23msec (r=0.79), ΔQRS 12±13msec (r=0.78), and ΔQT
20±19msec (r=0.9). The AW6 automated rhythm analysis yielded a 75%
specificity and found:  1) 40/61 (65.6%) “accurate”, 2) 6/61
(9.8%) “accurate with missed findings”, 3) 14/61 (23%) “inconclusive”, and
4) 1/61 (1.6%) incorrect. Conclusion: The AW6 can accurately measure
oxygen saturation when compared to hospital pulse oximeters in pediatric
patients and provide good quality single lead ECGs that allow for accurate
measurement of RR, PR, QRS, and QT intervals with manual interpretation.
The AW6-automated rhythm interpretation algorithm has limitations for
smaller pediatric patients and patients with abnormal ECGs.