Pulse oximetry methods: opportunities and limitations

The aim of this review was to evaluate the current literature on various methods of pulse oximetry, their advantages and disadvantages. Modern pulse oximetry methods generally correlate well with invasive saturation monitoring, which makes it possible to be widely used in clinical practice. At the same time, in order to improve the accuracy of saturation measurements, existing limitations of various pulse oximetry methods should be taken into account. The emergence and introduction into clinical practice of reflectance pulse oximetry can largely compensate for the limitations of traditional transmission pulse oximetry regarding peripheral hypoperfusion, low response time, and features of patient's nails. In the event of special situations when pulse oximetry may not be accurate enough (carbon monoxide poisoning, methemoglobinemia, severe anemia, severe tricuspid insufficiency, etc.), a thorough clinical assessment of the patient is recommen ded, as well as invasive saturation monitoring.