Pulse Oximeters for Home Use/Covid - Buyer Beware

[Joes Place]

In response to a thread where these came up, here's your warning to not waste your money.

The Accuracy of 6 Inexpensive Pulse Oximeters Not Cleared... : Anesthesia & Analgesia

ising questions about performance. METHODS: The accuracy of 6 low-cost finger pulse oximeters during stable arterial oxygen saturations (Sao2) between 70% and 100% was evaluated in 22 healthy subjects. Oximeters tested were the Contec CMS50DL, Beijing Choice C20, Beijing Choice MD300C23...

journals.lww.com

MOST of these which haven't been FDA approved (or CE Marked) can be really really inaccurate. As in, mostly useless.

RESULTS: ​

Pulse oximeter readings corresponding to 536 blood samples were analyzed. Four of the 6 oximeters tested showed large errors (up to −6.30% mean bias, precision 4.30%, 7.53 ARMS) in estimating saturation when Sao2 was reduced <80%, and half of the oximeters demonstrated large errors when estimating saturations between 80% and 90%. Two of the pulse oximeters tested (Contec CMS50DL and Beijing Choice C20) demonstrated ARMS of <3% at Sao2 between 70% and 100%, thereby meeting International Organization for Standardization (ISO) criteria for accuracy.​

​

CONCLUSIONS: ​

Many low-cost pulse oximeters sold to consumers demonstrate highly inaccurate readings. Unexpectedly, the accuracy of some low-cost pulse oximeters tested here performed similarly to more expensive, ISO-cleared units when measuring hypoxia in healthy subjects. None of those tested here met World Federation of Societies of Anaesthesiologists standards, and the ideal testing conditions do not necessarily translate these findings to the clinical setting. Nonetheless, further development of accurate, low-cost oximeters for use in clinical practice is feasible and, if pursued, could improve access to safe care, especially in low-income countries.​

Figure 1.

Bias (pulse oximeter oxygen saturation [Spo2] − arterial blood oxygen saturation [Sao2]) is plotted against Sao2 measured by either an ABL90 (panels A–C) or OSM3 (panels D–F) hemoximeter (Radiometer). Mean bias is shown by a solid horizontal line. Dashed horizontal lines are the upper and lower limits of agreement. Regression lines and equations are shown on the graphs with 95% confidence intervals for slope. Individual subject data are shown by different colored markers and trendlines. Panels A–C represents one group of 11 subjects, whereas panels D–F represent a different group of 11 subjects (A, Starhealth SH-A3; B, Jumper FPD-500A; C, Atlantean SB100 II; D, Contec CMS50DL; E, Beijing Choice C20; F, Beijing Choice MD300C23).

Figure 2.

Bias (pulse oximeter oxygen saturation [Spo2] − arterial blood oxygen saturation [Sao2]) is plotted against Sao2 measured by either an ABL90 (oximeters 1–3) or OSM3 (oximeters 4–6) hemoximeter (Radiometer). Each oximeter is indicated by separate markers.

(If the figures won't come up, go to the link and view them in the slideshow or gallery)

I did a little homework on these, and what I found is a bit illuminating. Nearly ALL the oximeters on Amazon or Walmart are the "crap" ones. The ONLY ones that are FDA approved and available on Amazon require a "business account AND a medical registration (license)" to purchase. Thus, anything actually clinically useful isn't being sold OTC on those sites, to preserve supply for places that need them (clinics, schools, etc).

HOWEVER, there are places you can get the FDA approved ones, and they don't cost all that much more than the rando-crap ones. Walmart does appear to have ONE listing for one of these.

Basically, if you want to know if the one you're looking at is FDA approved, EITHER it will state it on the listing OR the model AND the actual manufacturer will show up in the NIH and FDA device databases.

I have a few of these saved I can dig up, if people are interested.

 

[Joes Place]

Example:
CMS-50DL model

You can find this on Amazon, BUT it is not the model made by the FDA approved manufacturer, Contec

Here is the typical Amazon link:
www.amazon.com/50-DL-Pulse-Oximeter-Neck-Wrist/dp/B004BJT9OE/

The maker is "ClinicalGuard", not Contec, the company that got the model FDA approved.

This is the info you pull up when you search at the NIH device link:
https://accessgudid.nlm.nih.gov/devices/06945040101598

The manufacturer of the APPROVED device is Contec.
ClinicalGuard made a knockoff which has never been evaluated for accuracy.

Many of the Amazon links will assert they are "manufactured in a facility that is CE approved". NOT THE SAME as the device being FDA and CE approved. At all.

Wal Mart DOES list this model AND the correct manufacturer, and it's only $30
Not 100% sure I trust this one, because it doesn't list FDA approved in the add BUT the model AND manufacturer match the regulatory database info, so it's more likely to be "legit" than most others.

I do have some links I dug up to ones sold that ARE listed as FDA approved, and they are also only $30-40.