The magical Pulse Oximeter has absolutely changed the world of medicine and I feel every physician, NP & PA must carry one besides a stethoscope. This ubiquitous device was invented by a Japanse engineer Takuo Aoyagi. He passed away recently in 2020 and Japanese docs penned an interesting tribute to him .
While Pulse Oximeters can be absolute life savers, they also suffer a major flaw ! They overestimate Blood Oxygen Levels (or Oxygen Saturation or ‘O2 sats’) in darker skinned people as several studies have shown. In other words, Pulse Oximeters can show a falsely high or normal oxygen blood level in people of color. This is called ‘Hidden Hypoxemia’, which cause severe & sometimes fatal organ failures since they don’t receive oxygen treatment even when their bodies need it.
This error has to do with how Pulse Oximeters work – they measure Oxygen Saturation indirectly from the differential absorption & transmission rates of red versus infrared lights as they pass through a translucent part of our body (such as finger tips or ear lobes). This color-based science behind the magic can give wrong readings in people of color as they absorb more light.
This small but important detail can be easily forgotten by healthcare providers taking care of such patients on a busy shift. More than 20 states have now joined a lawsuit urging the FDA for Pulse Oximeters to carry mandatory warnings & reminders about their racial bias. A copy of the letter sits on the Department of Justice website.
“It is imperative that the FDA act now to prevent additional severe illness and mortalities
Nov 2023 Multistate state letter to FDA regarding Pulse Oximeters
among darker skinned people resulting from inaccurate or misleading pulse oximeter readings“
Here’s a short YouTube video explaining this Pulse Oximeter error :
Don’t miss these fun posts! Subscribe via email 📩 | |
