Adenosine triphosphate (ATP) is the biochemical way to store and use energy. F or your muscles -- in fact, for every cell in your body -- the source of energy that keeps everything going is called ATP.
An approximate blood oxygen level can also be estimated using a pulse oximeter â a small device that clips on your finger. Though the pulse oximeter actually measures the saturation of oxygen in your blood, the results are often used as an estimate of blood oxygen levels.Normal pulse oximeter readings range from 95 to 100 percent, under most circumstances. Values under 90 percent are considered low.1  Causes.n approximate blood oxygen level can also be estimated using a pulse oximeter â a small device that clips on your finger. Though the pulse oximeter actually measures the saturation of oxygen in your blood, the results are often used as an estimate of blood oxygen levels.
Arterial Blood Oxygen. While a pulse oximeter is the most common device used to determine your blood oxygen level, it is sometimes necessary to analyze blood taken directly from an artery to assess your oxygen level. This measurement is called an arterial blood oxygen. A normal arterial blood oxygen level typically falls between 75 and 100 mmHg. Your blood carbon dioxide level and pH -- a measure of acidity or alkalinity -- are usually measured along with the arterial blood oxygen level.