The full name of oxygen conservation is oxygen saturation, which includes arterial oxygen saturation prompted by arterial blood gas and oxygen saturation measured by fingertip. The normal value of arterial oxygen saturation is 80-100 mmHg, and if it is below 60 mmHg, it is called type I respiratory failure, while the normal value of pulse oximetry is greater than 90%. If arterial oxygen saturation is at 60 mmHg, then pulse oximetry is at 90%. In institutions where primary conditions do not allow for checking blood gas analysis, it is possible to infer whether the arterial oxygen saturation is below 60 mmHg by whether the pulse oximetry is below 90%. It indicates type I respiratory failure, which is severe and requires high-flow oxygen to be given as soon as possible. Endotracheal intubation can also be given where available to alleviate as soon as possible the harm caused by hypoxemia and type I respiratory failure to multiple systems throughout the body. Therefore, in institutions where arterial blood gases cannot be checked in primary hospitals, their prompting is very important.