A pulse Oximeter can help you check your Oxygen Level without needing to be stuck with a needle.
A pulse oximeter is a small unit with a built in finger/toe clip. Beams of light from the device pass through the blood in your finger and measure your oxygen level without you even noticed it.
The blood oxygen level measured with a Pulse oximeter is called your oxygen saturation level (abbreviated O2sat or SaO2). This is a percentage of how much oxygen your blood is carrying compared to the maximum it is capable of carrying. Normally, more than 89% of your red blood should be carrying oxygen.
The beams of light calculate the percentage of your blood that is carrying oxygen. It also provides a reading of your heart rate (pulse).
The oxygen level from a pulse oximeter gives an accurate reading, very similar of the one obtained by an arterial blood gas. For example, if your oxygen saturation reads 92% on the pulse oximeter, it may be actually anywhere from 90 to 94%. The oximeter reading may be less accurate if a person is wearing nail polish, artificial nails, has cold hands, or has poor circulation.
Some people are prescribed a pulse oximeter if they have or could have periods of low oxygen; for example, when you are exercising or if you travel to high altitude. Having a pulse oximeter in these cases will allow you to monitor your blood oxygen level and know when you need to increase your supplemental oxygen flow rate.
Your pulse oximeter measures your oxygen saturation, or percentage of blood carrying oxygen. To get the best reading from your oximeter, you need to make sure enough blood is flowing to the hand and finger wearing the device. The best reading, therefore, is achieved when your hand is warm, relaxed, and held below the level of your heart. If you smoke, unfortunately, the reading on your oximeter may be higher than your actual oxygen saturation. This is because smoking increases carbon monoxide levels in your blood, and the oximeter cannot tell the difference between the gas carbon monoxide from oxygen. If you smoke, talk to your health care provider about how to properly read your oximeter numbers.