A pulse oximeter (PO) is a small and lightweight tool which is used to measure the amount of oxygen in the blood. The procedure does not require any needling and can be carried out painlessly simple by attaching the device to the body part.
The oxygen level measured by the device is known as the oxygen saturation level. The device is especially benefitted to women who are pregnant, young infants and to those who have respiratory, heart conditions or infections. 
Every part of human body needs oxygen to survive. Deficiency of oxygen in the body leads to malfunction of body organs and death. The lungs are responsible to filter oxygen while the heart helps in distributing them throughout the body via bloodstream. A protein named haemoglobin found in the red blood cells is involved in carrying and transporting the oxygen.
The PO measures the amount of oxygen in these proteins and says about the functioning of the body parts. The normal oxygen saturation level should be around 95-100 per cent. Less than 90 per cent is considered abnormal and requires immediate medical attention.
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Individuals with conditions such as COPD, pneumonia, asthma, heart failure, lung cancer or anaemia usually need pulse oximeter. Other common uses of PO include: 
PO is like a small clip which is attached to finger, foot, earlobe, wrist or other body parts to measure oxygen level. From one side of the clip, light comes out while on other side, sensor is attached for reading. 
The light passes through the blood and measure the oxygen saturation level by using a complex equation. The amount of light absorbed in both oxygenated and deoxygenated blood is used as a value.
According to the WHO, CDC and other medical researchers, the primary symptoms of COVID-19 include shortness of breath and pneumonia. As PO helps in identifying the oxygen levels, the device can monitor the exact oxygen rate in the lungs, and accordingly help medical experts to give a proper treatment to the patients.
In a pilot study, it was found out that pulse oximeter has been helpful in the early self-proning of patients who have been admitted to the emergency department. The device has helped in identifying patients who needed oxygen supply followed by determining their severity and giving them the required ventilation or treatment. 
The device also helps in diagnosing the lung condition in COVID-19 positive patients.
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Pulse oximeter is a low-cost electronic device with highly accurate reading. The device is widely used in healthcare sectors. PO has been helpful in treating many COVID-19 patients efficiently. Medical experts suggest that the device should not be used at home as it may give false reading when not inserted properly under the medical supervision.
As of today, the total confirmed COVID-19 cases in India is 74,281 with 24386 recovered cases and 2415 deaths. It's been months the world is fighting the COVID-19 infection. Numerous medicines and equipment have been developed until now to combat the infection.
Among all the useful tools developed, a pulse oximeter is also making news due to its simple and effective property. Take a look at its importance and uses to combat COVID-19.
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