Introduction to Pulse Oximeters

For the assessment of respiratory function, it is not uncommon to come across that small device that is clipped to one of your fingertips or earlobe called a pulse oximeter. Generally, the primary purpose of this gadget is to provide an estimate of the oxygen saturation of hemoglobin that cannot be easily detected by physical assessment and the human eye.

The respiratory status of a person may be evaluated through a variety of ways. But diagnostic studies are more accurate. For one, pulse oximetry can give a fast and accurate way of monitoring a patient’s oxygenation. Prior to its development, a patient’s oxygenation can only be determined through arterial blood gas measurements which requires a few minutes for the results to come out. Although ABGs convey very accurate and reliable results, this procedure is usually not considered in situations that require immediate and continuous observation of oxygenation. The pulse oximeter is a safer, noninvasive option which makes it ideal for continuous monitoring. It does not replace arterial blood gas studies, but it is an effective tool to keep an eye for sudden changes in blood oxygen saturation. It can be used in any setting where oxygen saturation monitoring is required such as the hospital, during surgery, and at home.

The pulse oximeter operates based on the principle that red and infrared light absorption varies depending on the color between oxygenated and deoxygenated blood. A sensor is attached to a thin portion of the patient’s body, such as the fingertip or earlobe, and detects the light signals that are reflected by blood present at these sites. However, the device also has its own limitations. Sometimes, the values obtained may be unreliable especially when the patient has severe anemia or a high carbon monoxide level. Thus, it is really a must for both health workers and patients/users to use the pulse oximeter wisely and assume certain responsibilities to monitor its efficiency.