Pulse oximetry is the method by which the level of saturation of oxygen gas in the blood is monitored. The device used to do the monitoring process is referred to as a recording pulse oximeter. The sensor must be pinned across a thin organ. In adults earlobes or fingertips are the best while in infants feet or hands can do. The percentage of blood hemoglobin loaded with oxygen is monitored and displayed on the screen.

Devices with an alarm system are a good option to check for. Such gadgets make audible sounds to inform patients when the level of concentration of oxygen has fallen below certain levels. This ability is particularly vital at night when sleeping. People with poor or impaired eyesight or mobility problems may also benefit from alarms.

The functioning of an oximeter is very simple and is mainly based on difference in absorption of light. The device has a processor and a pair of LEDs, which face a photodiode. The photodiode is normally separated from the LED by a translucent body part like an earlobe. One LED is red in color at 660nm wavelength while the other one is infrared at a wavelength of 940nm. At such wavelengths, absorption of light by hemoglobin that is loaded with oxygen and that which is not is very different.

The diodes flash approximately 30 times every second. The accuracy could be gauged by the consistency of the flashing per minute. For a device to be considered good it should have high accuracy with mechanisms of letting users know if the readings displayed are wrong. Users must also be alerted of inaccurate readings due to interferences. Modern versions allow interfacing with computers hence allowing better reading of displayed data.

The oximeter can be integrated into a larger system that monitors several parameters in patients. Such capabilities are important because the user can collect a range of measurements from the system at once. Additional features such as portability and ability to measure and display the rate at which the heart beats are important too. In portable brands, the life of the battery and how long it takes to discharge are the key factors to consider.

Not all models have the same capabilities. Most recent recording oximeters have Bluetooth technology incorporate in them to allow for exchange of information with other devices. They also maintain a record of data collected over a period of time to allow for analysis of oxygen concentration patterns in patients. The records can also be printed for further analysis, referral, or record keeping.

Features to check for when buying a device include capability to maintain data from multiple people, availability of accessories, and simplicity of storage. Common accessories include cases for storage, log books, and batteries. The gadget should be simple to use and the shape should be convenient. Buyers have flexibility in picking color of a product since they come in a wide range or color shades.

It is advisable to read the manual that accompanies the product before using. The manuals provide important information about handling, storage, and maintenance. Malfunctioned products should be checked before they are used to avoid working with incorrect data.