Comparison of human smartwatch and transmittance pulse oximetry for evaluating peripheral oxygen saturation in...

Pulse oximetry is a valuable tool for monitoring animals during anesthesia and assessing the adequacy of administered oxygen therapy.

To compare the pulse oximeter readings obtained by the Garmin Fenix 5X plus (GF5Xp) smartwatch and transmittance pulse oximetry (TPO) in anesthetized dogs.

Twelve clinical canine patients requiring anesthesia for castration were prospectively enrolled in this study. The animals were premedicated with intramuscular dexmedetomidine at a dose of 5 µg/kg. Anesthesia was induced through intravenous administration of propofol and maintained using sevoflurane. The arterial hemoglobin oxygen saturation (SpO₂) readings obtained from the tongue using TPO (238 readings) were compared with measurements taken over the lateral side of the tibia using a GF5Xp smart wearable device (238 readings). This comparison was performed using a Bland-Altman plot, where the differences (%) between the methods were plotted against their mean SpO₂ (Gold standard - Device), and the limits of agreement were represented as the mean ± 1.96 times the standard deviation.

The SpO₂ levels in dogs were overestimated by the GF5Xp relative to the readings obtained by the TPO, with the bias of -0.3% (95% CI: -3.1%-2.5%).

GF5Xp may be interchangeable with TPO in dogs. Further studies are required to validate the accuracy of the GF5Xp in non-anesthetized dogs or dogs outside the physiological range.