Pulse oximeter, or SpO2 probe (saturation of peripheral oxygen probe) has come a long way since its invention at the end of the 20th century. The rapid adoption rate of different oxygen saturation monitor types is not surprising given that they can for most intents and purposes measure oxygen saturation in the remote parts of the body (far removed from the heart and lungs) accurately, non-invasively, and quickly. And all of this, depending on the pulse oximeter model, in a small portable package.

We will describe three types of pulse oximeter probes here. They each have a different usage that we will describe below. They range from individual compact finger pulse probes, to wrist pulse oximeters, and to disposable finger pulse probes.

Compact finger pulse oximeter probes

Compact finger pulse oximetry probe, or fingertip pulse oximeter, is designed to be small, portable, even wearable on a neck lanyard, and run for days on a single or double AA battery. As such, oxygen saturation levels will be easily read at home, at athletic events, by high altitude pilots and mountain climbers alike. Because of the digital pulse oximeter all-in-one design comprising of the display, microprocessor unit, and fingertip probes, they are normally used by a single person to prevent cross infection issues.

As compact as they may be, they are still rather cumbersome to wear for extended periods of time, and are therefore typically intended for spot measurements. For long-term measurements, wroist oxygen saturation oximeters are more convenient.

Disposable finger pulse SpO2 probe

These can be found in wrist pulse oximeters, but more commonly in hospital settings where first, oxygen saturation probes play an important role as a part of vital sign monitors, and second, the disinfection measures are paramount. Therefore using disposable finger pulse probes, and only using one probe with a single patient, can really help in this regard. Vital sign monitors typically will include heart rate probes, non invasive blood pressure cuffs, and oxygen saturation probes, thereby measuring the speed and the effectiveness of oxygen distribution throughout the patient's body.

Disposable finger pulse probes can be made very thin and flexible, and can be attached to a finger by a velcro strip as needed. Also, due to their light design and flexibility, they can be used as earlobe probes instead, in case patient's fingers are inaccessible for some reason.

Wrist pulse oximeters

Wrist oxygen saturation probes feature a separation of the display, controlling microprocessor with the memory, into one unit that is worn on the patient's wrist, and has an attached finger unit. The finger unit can be disposable or not. With this design, the wearing of the unit becomes quite seamless. Thus, wrist pulse oximeters are widely used for blood oxygen saturation measurements during sleep. Wrist oximeters will therefore have sufficient memory capacity to record the oxygenation data points.