The Onyx is the only finger pulse oximeter with scientifically proven accuracy in the most challenging cases, including patients with low perfusion or dark skin tones.
Three finger pulse oximeters and one tabletop pulse oximeter were attached to a subject who was breathing for the first minute using a
commercially available rebreather to induce hypoxia.
The chart below illustrates that over the course of the test, only the Nonin Onyx and Nellcor pulse oximeters accurately tracked
the subject's desaturation down to 81-82 percent SpO2 and back up to 96 percent SpO2.