JMIR Publications

ABSTRACT

Background:

Over recent years, technological advances in wearables have allowed for continuous monitoring of vital signs and oxygen. These devices have primarily been used for sports and general wellness and may not be suitable for medical decision making, especially in saturations below 90% and in patients with dark skin tones. Wearable clinical grade saturation of peripheral oxygen (SpO2) monitoring can be of great value to patients with chronic diseases, enabling them and their clinicians to better manage their condition with reliable real time and trended data.

Objective:

The objective of this study was to determine the SpO2 accuracy of the Movano Health wearable ring compared to arterial blood gas measurements in a hypoxia study based on the ISO 80601-2-61:2019 standard. Accuracy was evaluated over the range of 70-100% arterial oxygen saturation (SaO2) in volunteers with a broad range of skin tones (I to VI) using the Fitzpatrick scale during non-motion conditions. In parallel, accuracy was compared to a calibrated hospital-grade reference pulse oximeter (Masimo Radical-7).

Methods:

We performed a single-center, blinded hypoxia study of the Movano Health ring in 12 healthy volunteers at the Hypoxia Research Laboratory, DepartmWe performed a single-center, blinded hypoxia study of the Movano Health ring in 12 healthy volunteers at the Hypoxia Research Laboratory, Department of Anesthesia and Perioperative Care, University of California, San Francisco under the direction of Philip Bickler, MD, PhD, and John Feiner, MD. Each volunteer was connected to a breathing apparatus for the administration of a hypoxic gas mixture. To facilitate frequent sampling, a radial arterial cannula was placed in either wrist of each subject. One test ring was placed on the index finger and another test ring was placed on the fingertip. Arterial blood gas (ABG) analysis to determine oxyhemoglobin saturation (SaO2) was performed using an ABL-90 multi-wavelength oximeter (Hemoximeter, Radiometer, Copenhagen, serial 1393- 090R0359N0002). Pulse rate accuracy of the ring was also compared to the Masimo Radical-7 pulse oximeter.

Results:

A total of 258 SpO2 pairs were included in the analysis. The accuracy of the test ring in terms of root mean square error (RMSE) was 2.1% for both the fingertip placement and the finger placement compared to SaO2 while the Masimo Radical-7 had a RMSE of 2.8% compared to SaO2.

Conclusions:

The Movano Health Ring meets an acceptable standard of accuracy for both SpO2 and pulse rate under non-motion conditions. Clinical Trial: Performance of the Movano Health Ring in a Controlled Hypoxia Study: Prospective Observational Study, NCT05920278, https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000D1OS&selectaction=Edit&uid=U0006N37&ts=2&cx=756sqx