The Working Of A Recording Pulse Oximeter

By Marci Glover


Pulse oximetry is a method of monitoring the saturation of oxygen in a patient. The monitoring device used for this process is called a recording pulse oximeter. The sensor in the device is placed across a thin part of the body preferably the earlobe or fingertip in adults and foot or hand in infants. The device monitors the percentage of hemoglobin loaded with oxygen and displays the value on a 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.

Functioning of oximeters is based on disparity in light absorption. They have processors and two LEDs, which directly face a photodiode. The LED and the photodiode are separated by a light part of the body like earlobes. One LED is red in color and has a wavelength of 660nm while the second one is infrared with a wavelength of 940nm. The absorption of the LED lights by oxygenated and deoxygenated hemoglobin is very different. This is the working principle of the gadget.

The LED flashes at a rate of about thirty times in a second. A device that maintains the rate of flashing constant has a high accuracy. A good device is one that has high accuracy and also has some means of notifying the user in case of an incorrect reading. Presence of interferences that affect accuracy in the readings should also be disclosed to the user. Some modern models have computer interfaces allowing the user to see readings in a better way.

Recording oximeters are able to be incorporated into bigger systems, which monitor many parameters inside the human body. This ability is essential because multiple patient parameters can be recorded simultaneously. Portability and measurement of heart beats are the other features to check for when making a purchase. Battery life and discharge time are the primary factors for consideration in portable brands.

The abilities of various brands differs a lot. Bluetooth technology is incorporated in modern recording oximeters to facilitate the exchange of data among gadgets. They also permit for analysis of oxygen concentration patterns in patients for decision making. The analysis is possible from data records maintained over time. It is also possible to print records for record keeping, further analysis, or referral.

When purchasing, extra features to check for include capability to keep data for more than one user, availability of added accessories, and ease of storage. Added accessories include log books and cases for storage. The device must be easy to use with a good shape for convenience. A buyer has flexibility in choosing color of the product because there are many options.

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.




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