A pulse oximeter finger sensor is a device for measuring the oxygen content of the blood. By comparing the light absorption of the body against known tables, a pulse oximeter finger sensor can determine how saturated with oxygen the hemoglobin in the blood is. Hemoglobin molecules have four different points that can attach to an oxygen molecule, carrying it to the part of the body where it is needed. Without this oxygen, none of the organs could function, and the body would effectively choke to death. Hemoglobin should normally have ninety-five to one hundred per cent oxygen saturation, and a pulse oximeter finger sensor allows instant information on the blood's oxygen content.
Pulse oximeter finger sensors work by measuring the light absorption of the body. After the oximeter is clipped onto the fingernail, two LEDs send out light pulses at precisely set levels. One of the LEDs shines visible light at 660 nm and the other emits infared light at 910 nm. The light from these LEDs is partly absorbed by the hemoglobin and the rest is emitted back to the finger sensor onto a light reader. The amount of light is then interpreted and the amount of oxygen present in the patient's bloodstream is calculated. Often, pulse oximeter finger sensors also test other things as well, such as the pulse of the patient.
Some factors can interfere with the use of a pulse oximeter. Bright lights, since the machine determines oxygen levels by reading light strengths, can mislead the device. Nail polish that obscures the fingernail will affect the opacity and hurt the accuracy of the reading. In addition, certain substances used in surgery can affect the accuracy of the reading. Despite all this, a pulse oximeter finger sensor is small and portable, and provides accurate, continual readings and is usable by both medical professionals or the patients themselves.
