Health – Pulse oximeter an invaluable tool

It sure has been an unusual few weeks. Everyone is busy getting themselves ready for potential isolation. Throat lozenges, paracetamol and masks are racing off the shelves. But there is one item on the Covid checklist that has a few people perplexed. What is a pulse oximeter and do you really need one?

A pulse oximeter is a small device (which costs around $90) that is attached to your finger like a clothes peg. The result displayed gives an indication of the oxygen levels in your blood. For healthy adults this is 95 to 100 percent.

Usually a person with low blood oxygen will have symptoms such as tiredness or shortness of breath, but with Covid-19, many do not have symptoms of a low oxygen level. One of the most important early signs of Covid-19 patients deteriorating is a fall in the level of oxygen in the blood. However some patients with Covid-19 develop a form of oxygen deprivation called “silent hypoxia”. The lungs become inflamed and less efficient at absorbing oxygen but the blood oxygen levels drop so slowly that the patient doesn’t notice anything is wrong. Often these patients are very ill by the time they get to hospital. 

If you have Covid-19 and check your oxygen level at home you will know when you need medical attention – even if you don’t have symptoms that indicate a low oxygen level. If your reading is below 95 percent, you should seek medical attention. If it is below 92 percent, ring an ambulance.

If you do get yourself a pulse oximeter, be sure to get the device out of the box, before you really need it and find out what your normal readings are. For example, some people who have certain respiratory conditions normally have a lower blood oxygen reading, so their doctor may advise seeking help at a different oxygen level.

Pulse oximeters are usually very accurate. However there are some circumstances that may cause incorrect readings – for example poor circulation, cold or moving fingers. Nail polish may also cause a problem with pulse oximeter readings and is best removed as are acrylic nails!

Some smart watches and phones indicate blood oxygen levels, however these devices often provide inaccurate information and should not be used for the purposes of monitoring a medical emergency.

Do not completely rely on the pulse oximeter to assess your health. If at any time you experience other worrying symptoms such as shortness of breath at rest, difficulty breathing or your symptoms suddenly become worse, call 111 for an ambulance.