A pulse oximeter is a device which is used to monitor oxygen saturation (SO2) or amount of oxygen
carried in a person’s body. The sensor digital device is placed on thin part of a person’s body; generally a
fingertip or earlobe is considered for such process or may be across a foot for a child (infant). The
oximeter device emits light which consists of two wavelengths that passes through the patient’s body to
a photo detector. These two lights of different wavelength beams in the small vessels or capillaries
which consist of blood (circulating blood) and these light beams are responsible for determination of
amount of oxygen present in the blood along with the current pulse rate in a person’s body. The pulse
oximeter measures the change that is observed by the light of emitted wavelength which is the basic
working principle. This measurement allows the determination of absorbance due to pulsing arterial
blood only excluding the venous blood, skin, bone, fat and muscle.
This monitoring of blood oxygen displays the percentage of blood which is loaded with oxygen.
Generally the normal oxygen blood percentage in any body is usually greater than 95% in a normal adult
human body. An oxygen blood percentage of 92% or less than 92%, then it come under the category of
low blood oxygen level. For an adult above 18 or 19 years of age normal pulse rate values are 60-80
beats per minute. In some cases, the heart rate increases during some workout or exercise and oxygen
saturation percentage level might result to decrease.
The pulse oximeter measures two different things, the pulse rate and secondly the level of oxygen in the
blood. The basic idea is that the lungs perform the functioning of transferring oxygen from air to blood
stream and then this sucked air is pumped to all the organs of the body with the help of heart. Thus the
oxygen level in the blood is measure by drawing blood from artery which accurately measures each of
the pulse rate and oxygen level currently in a person’s body.