Oxygen saturation is one of the important physical indicators of the human body. It is very necessary to use a handheld infant SpO₂ monitor to monitor newborns, and it is also commonly used for critically ill newborns, such as those with respiratory system diseases, lung obstruction, thrombus system diseases, and to monitor the vital signs of newborns after surgery. This prevents critical conditions in newborns caused by hypoxia.

End-tidal carbon dioxide (ETCO2) has increasingly been used in clinical settings as a non-invasive monitoring technique. Due to its small size and ease of connection, it has become a regular feature in ambulances. ETCO2 is the gold standard for confirming advanced airway placement. It can also determine the survival likelihood of cardiac arrest patients, assess the severity of sepsis, identify pulmonary embolism earlier than SpO2 and detect respiratory depression following the administration

The process of human metabolism is a biological oxidation process, and the oxygen needed during metabolism enters the blood through the respiratory system. This oxygen combines with the hemoglobin (Hb) in red blood cells to form oxyhemoglobin (HbO₂), which is then transported to various tissues and cells in the body. Generally, SpO₂ is considered normal if it is not lower than 94%, and anything below 94% indicates insufficient oxygen supply.