Pulse Oximeter is a medical device that is highly recommended to monitor a patient’s haemoglobin and its saturation. Based on the principle of sensory and touch, the device allows you to place a part of the instrument on the patients skin, usually a fingertip or earlobe. In case of infants, the sensor is placed on the foot.
Pulse Oximeter is basically a non-invasive method wherein the instrument is capped to calculate the level of oxygen in your blood. It measures the difference between the levels of red pigment haemoglobin that contains all the oxygen supply to the blood. What comes forth is that oxygenated hemoglobin ("oxyhemoglobin") and nonoxygenated hemoglobin ("deoxyhemoglobin") spot colour differences in the blood.
Though the device became common in 1980’s, the same was developed based on an 18th century principle known as the Beer’s law. Around 1935, it was German Physician Karl Matthes who introduced the ‘first 2-wavelength ear O2 saturation meter’ which came with red and green filters. The device was introduced to measure O2 saturation.
It was not until 1940 that the original Pulse Oximeter was invented by Glenn Allan Millikan. There were a few other scientists and physicians who worked largely on the device, and the final verdict came when Takuo Aoyagi and Michio Kishi launched a better and refined Pulse Oximeter in 1972.
What came later were adaptations and improvements to the product. As of 2012, the device vaunts of 802.11 wireless radio and an integrated touchscreen interface. These changes were incorporated by Masimo with a view to help doctors and clinics keep a tab on the patient’s haemoglobin level and changes even when they are not in the hospital.
How it works
The Pulse Oximeter works on a very simple concept of detecting the change in the colour of blood. Since the colour depends upon the quantity of oxygen it has been saturated with, the device catches that quickly and detects any change by an alarm sound.
The medical device comes with two beams of light—one is red in colour which you can see when the product is used. The other is an infrared light which you cannot see. These two lights allow the Pulse Oximeter to detect immediately what colour is the blood made of and the level of oxygen it is carrying.
Since there are other factors too that can influence the change in colour, the device works to detect only slight changes in the overall colour. It works best when there is a strong pulse in the finger or where the device has been clipped.
Steps to use Pulse Oximeter
- If your finger nail has any nail polish, it is advisable to remove that. The device does not detect efficiently if there is any kind of colour on the finger nail.
- Place the device on the finger. It is seen that it works best on the index and ring finger.
- It is very important to be still for the reading to be accurate. Any movement of either the hand or the finger interferes with the results.
- Since the sensor takes between a few seconds and a minute to detect the results, it is advisable to be patient.
- Once the results are out, it does make sense to understand them—the device gives results in percentage. So if the reading says 80%, this means that your blood is saturated with the same percentage of oxygen. According to doctors, 90% or above is a sign of healthy oxygen supply.
- To determine your baseline, use the device for several days. It is advisable to take readings daily for the first few days.
The Pulse Oximeter comes laden with the following advantages:
- It is a very important device for patients suffering with asthma, emphysema, chronic obstructive pulmonary disease (COPD), chronic obstructive airway diseases (COAD), and other respiratory conditions. The device is also recommended for patients with respiratory problems.
- Since it is a no-fuss method of knowing the oxygen saturation in blood, it allows you to check the same regularly and at times when situation becomes critical.
- Exercising is something each patient is asked to do by doctors. This results in an improved physical state. But along with it, comes shortness of breath. This makes it necessary for patients to monitor their oxygen level and adjust the course and duration of exercising accordingly.
- The device is simple and gives speedy signals. This makes the product very useful in emergency situations.
- It is often seen that cardiac patients experience very low oxygen levels. Pulse Oximeter helps to monitor their condition as well.
- Pulse Oximeter is portable and boasts of battery-operated units which make it very useful for pilots, mountain climbers, and other people in high altitude to make use of the device and guard against hypoxia.
- The device is also beneficial for athletes practicing in high altitudes.
A few warnings
Before you start using the Pulse Oximeter, make sure you understand the following:
- There should be no nail paint or any other form of mark on the finger.
- While the device can be placed on toes and earlobes, the situation works much better on infants.
- The device won’t give any reading on cold fingers. It therefore becomes essential to warm your hand. You can do this by using a warm towel.
- The device would not be able to pick up any reading if the circulation is very poor.