Pulse Oximetry: Accuracy and Limitations, Uses, Readings & How It Works

Written by Rayden Sam Posted on 2024-01-02

A Pulse Oximeter is a tool that can be used to measure the amount of oxygen in the blood without hurting the person.

Pulse Oximeter-Introduction: As a sensor, an Oximeter instrument can use the earlobe or the tip of the finger, among other places, to get to know the results. There is a source that sends out light with two different wavelengths, and on the other side is a detector that reads the light based on its wavelength. These frequencies were chosen because tissue, fat, and even nail polish would not change them.

Since this was the case, they were the best choice. Only when blood flows through the arteries can it be changed? A computer takes the information that the sensors give it and puts it on a screen.

A pulse oximeter is not a fool-proof way to see if a patient is getting enough oxygen, but it does have the benefit of giving a result quickly and giving updates in real-time.

Reason for using Pulse Oximeter-

A Pulse Oximeter can be used to find out if the blood has enough oxygen in a variety of situations, such as surgery, other procedures that require sedation (like bronchoscopy), adjusting the amount of extra oxygen as needed, the effectiveness of lung medications, and how well a patient can handle more activity (also known as oxygen saturation). Here are only a few more reasons that could be given, but this list is not complete:

Mechanical ventilation is what a ventilator is, and it is used to help a person breathe.
Sleep apnea is marked by short pauses in breathing that happen repeatedly during the night.
Health problems, like coronary artery disease, congestive heart failure, anaemia, lung cancer, asthma, or pneumonia

How does a Pulse Oximeter work?

A Pulse Oximeter is a device that helps determine the amount of oxygenation inside the body by using the light-absorptive characteristics of haemoglobin and the pulsating nature of blood flow in the arteries. For starters, oxygen-rich arterial haemoglobin appears a bright red colour, whereas oxygen-depleted venous haemoglobin seems a darker red colour.

Second, the volume of blood passing through the arteries slightly increases with each beating. It is due to the continual dilation and expansion of the artery walls. Minor as the increase in blood volume may be, it correlates with a rise in the concentration of oxygen-carrying haemoglobin. Presently, the arterial blood has the highest concentration of oxygen-rich haemoglobin ever recorded.