A drawback
The green light approach could be “game changing,” Dr. Chander said. But there is a drawback.
Since green light doesn’t penetrate as deeply, this approach measures blood oxygen saturation in capillary beds (small blood vessels very close to the skin surface). By contrast, traditional oximetry measures oxygen saturation in an artery as it pulses – thus the name pulse oximetry.
Valuable information can be obtained from an arterial pulse.
Changes in arterial pulse, known as the waveforms, “can tell us about a patient’s hydration status [for instance],” Dr. Chander said. “In a mechanically ventilated patient, this variation with a patient’s respiratory cycle can give us feedback about how responsive the patient will be to fluid resuscitation if their blood pressure is too low.”
Given such considerations, the green light method may be useful as an adjunct, not a full replacement, to a standard pulse ox, Dr. Chander noted.
A version of this article appeared on WebMD.com.