Performance of the new SmartCardia wireless, wearable oximeter: a comparison with arterial SaO2 in healthy volunteers

Abstract

Abstract Background Our goal was to evaluate the performance of a new wearable arm located pulse oximeter. Methods Twelve volunteers were monitored with three pulse oximeters and underwent desaturation to 70% SaO2. We compared the accuracy of SpO2 reading from the SmartCardia system with SpO2 using two well established devices (Masimo and Nellcor) as reference. Oximetry was performed at different level of oxygen saturation varying from 70 to 100%. Bias, ARMS and precision were evaluated using Bland-Altman plots. Results The mean (SD) differences between SaO2 compared to SpO2 and the devices were as follows: SaO2 versus Masimo 2,12 ± 1,01% (95% CI 1,45 to 2,79), SaO2 versus Nellcor 0,78 ± 0,58% (95% CI − 0,29 to 1,65) and SaO2 versus SmartCardia 0,42 ± 0,24% (95% CI − 0,64 to 1,46). The bias between SmartCardia, Masimo, Nellcor devices and SaO2 was 0.16 (95% CI 0.05 to 0.33) and LoA (level of agreements) 2.96 (95% CI − 2,68 to 2,89) for SmartCardia, 2,02 (95% CI 1,49 to 2,54) and LoA − 6 to 11 for Masimo, and 0,76 (95% CI 0,5 to − 1) and LoA − 3,5 to 5,0 for Nellcor. ARMS for the 70–100% SaO2 range was 1,4 for SmartCardia, 5,0 for Masimo and 2,31 for Nellcor. Conclusions The new wireless SmartCardia SpO2 measurement system demonstrated in-line results, bias, ARMS and precision in healthy volunteers, when compared with the gold standard SaO2 and with two well established systems, Masimo and Nellcor. Trial registration The present trial was prospectively registered at UCSF record (registration number:10–00437), on March 8, 2021.

Keywords

• Oximetry
• Nellcor device
• Masimo device
• SpO2 measurement
• SmartCardia