Hyderabad: Amid a surge in COVID cases, the demand for infrared thermometers and finger pulse oximeters is skyrocketing. For the last couple of days, a message about a mobile phone application is being forwarded, shared and re-tweeted on social media. The users claim that the fitness app will measure the percentage of oxygen saturation in hemoglobin (SpO2) by placing the finger on the camera of a mobile phone.
App for oximeter, blood pressure and Heart rate.
Give permission of camera to measure on App.
— Aravind (@aravindcherry) July 25, 2020
A number of users installed the app in the last two days but most of them are still skeptical about its functioning. News Meter received few requests to fact check the claim.
The claim that mobile apps can be used as alternative to Pulse oximeters or patient monitors is FALSE.
The app that was shared largely on social media is Pedometer 2018, available at https://play.google.com/store/apps/details?id=com.pedometer.sixpackworkout.loseweight
The Archived page of this app can be found here.
It is a fitness app like many other apps available in the play store. The app provided an option to check the SpO2 level in the blood by placing the finger on the camera on the rear side. This feature is touted as an alternative to the Pulse Oximeter. People are advising others to use the app to regularly monitor their SpO2 levels.
To verify the claim, we installed the app and checked whether it is really working. We used this app on 10 people and SpO2 reading was either 99 or 98. We verified it with a patient with no breathing complications in HCG MNR Cancer Hospital and found that the app showed SpO2 reading as 98 when the high-end patient monitor with a finger probe showed it as 96.
Doctors said SpO2 should be greater than 95 for human beings under ideal conditions. They suggest external support when the SpO2 falls below 90. In this COVID pandemic days, the people with comorbidities should be very careful and approach the hospital if they feel any discomfort in breathing.
Dr. Putta Siddhartha Reddy, an emergency medicine specialist in KIMS Hospital said people should not depend on the camera-based apps to test the SpO2. He explained that the regular finger oximeter or probe connected to the patient monitor sends an infrared ray through the finger on one side and receives at the other side.
The infrared ray passes through the blood in the finger and calculates the percent of the ray spectrum received on the other side. The infrared ray losses its spectrum when the oxygen in the blood is reduced or SpO2 is low and passes through the blood in full amount when the blood is rich with oxygen.
In the mobile apps using the camera to detect the SpO2, the white light falling on the other side is calculated and the amount of redness the camera able to capture is given as the SpO2 reading. This reading changes more when the light falling on the finger changes, when the finger is tattooed or nail polish is applied, etc, and cannot be reliable in emergencies. He said that the difference between the readings of the oximeter and the app will be high when they are tested on a patient who is on oxygen support.
Dr. N Ramana Reddy, a surgical oncologist at HCG MNR Cancer Hospital, said there are few models of mobiles that have inbuilt health modules, like models of Samsung Note and smartwatches, show SpO2 reading. He said that the companies making these instruments provide a disclaimer that these readings are for recreational purposes only, but not for medical purposes.
After becoming viral on social media, the app Pedometer 2018 is removed from Google Play Store. But, still there are a number of such fitness apps available.
Hence, it is understood that there are different apps claiming to provide SpO2 readings when used in certain models of mobile phones and fitness bands. Therefore, the claim that these apps are an alternative to the pulse oximeters or patient monitors is FALSE.