Pulse Oximeter Basics
This color of light is used in pulse oximetry at 660 nm.
What is red light?
This pigment, which has a high absorption of light at higher concentrations, may affect the accuracy of SpO2 readings from people of color.
What is melanin?
This color of light penetrates the skin to a depth of only 2-3 mm, reducing the interference of melanin in SpO2 readings.
What is green light?
This law states that the concentration of a solute in a solution is determined by the amount of light (of a specific wavelength) absorbed by the solute.
What is Beer’s Law?
In people who smoke, pulse oximeters cannot distinguish between oxyhemoglobin and this molecule, leading to high SpO2 readings.
What is carboxyhemoglobin?
This system mathematically adjusts light absorbance data, increasing the signal-to-noise ratio in pulse oximeters that use it.
What is an adaptive algorithm?
In pulse oximetry, oxygenated blood absorbs more of this type of light than deoxygenated blood.
What is infrared light?
In this process, a standard curve depicting the light-absorption ratio influences a pulse oximeter’s algorithms for determining SpO2.
What is calibration?
This type of pulse oximeter reduces the interference of melanin and consistently produces accurate readings across people of different races.
What is a laser-based oximeter?
This optical technique measures the changes in a tissue’s blood volume.
What is photoplethysmography?
A study led by researchers at this institution found that clinicians often gave less supplemental O2 to people of darker skin tones.
What is Harvard Medical School?
This technique generates an image by sensing ultrasound waves produced by hemoglobin.
What is photoacoustic oximetry?
SpO2 is calculated by subtracting the desired data from total data, which is collected during this phase of the cardiac cycle.
What is systole?
This type of nail polish causes larger inaccuracies in SpO2 readings than regular nail polish.
What is gel nail polish?
This device measures a patient’s skin tone to help calibrate pulse oximeters.
What is a spectrophotometer?