CMS pulse oximeters are medical gadgets that help medical professionals determine, somewhat indirectly, if a patient is getting enough oxygen. The devices clip onto the finger, the earlobes or, in infants, a foot. What they actually measure is the amount of hemoglobin that is fully loaded up with oxygen. In most people, this figure should be at least 95% or more.
It isn't obvious how a non-invasive instrument can measure with any degree of accuracy something down to the molecular level. Without getting too technical, oximetry works on the principle that different substances absorb light differently. Two different wavelengths of light are passed through the patient and the instrument is able to determine the absorbance, and therefore the concentration, of oxygen in pulsating arterial blood.
While this is an excellent way of screening sick people from really sick people, a more accurate measurement is obtained by measuring oxygen directly from arterial blood. This is important in places like intensive care units or when a patient is under anesthesia having an operation.
This is a painful and invasive procedure and there needs to be a good reason for collecting this information. Patients who have their arterial blood sampled while they are awake describe the sensation as akin to having a needle stuck directly into their bone. Unfortunately, because one of the circumstances in which this information is important is while a patient is under an anesthetic, so the poor patient has to have the needle inserted while they are still awake.
Pulse oximeters are used a lot in research. Oxygen saturation is one of the parameters that is measured as part of sleeping studies that are investigating whether an individual suffers from sleep apnea, a condition where they stop breathing for brief periods during the night. This is a potentially fatal condition because it can lead to heart attack or stroke. At the very least, it makes people sleepy and unproductive the next morning.
There are two categories of sleep apnea, neurological and obstructive. Obstructive sleep apnea (OSA) is more common than neurological sleep apnea, but no less dangerous. Treatments may include a device that is prescribed by a dentist to keep the mouth partially open at night, continuous positive airway pressure (CPAP) or, in extreme cases, surgery to correct an anatomic deformity that makes the airway unable to open.
Central, or neurological sleep apnea, is less common and harder to treat than OSA. Instead of stopping the breathing process, the brain doesn't attempt it. There is often a serious condition underlying neurological OSA that affects the brain stem. This is the brain area that is responsible for breathing and heart rate. Neurological sleep apnea can happen by itself or in combination with OSA.
Although anyone can have any type of sleep apnea, the major risk factors are male gender over the age of 40 and being overweight. Sleep apnea is particularly dangerous in infants, who can stop breathing for as long as twenty seconds. This is a very daunting prospect for new parents. Fortunately, there are apnea alarms available that will alert the parents when a baby stops breathing for a set number of seconds. It is also possible to obtain CMS pulse oximeters for home use.
It isn't obvious how a non-invasive instrument can measure with any degree of accuracy something down to the molecular level. Without getting too technical, oximetry works on the principle that different substances absorb light differently. Two different wavelengths of light are passed through the patient and the instrument is able to determine the absorbance, and therefore the concentration, of oxygen in pulsating arterial blood.
While this is an excellent way of screening sick people from really sick people, a more accurate measurement is obtained by measuring oxygen directly from arterial blood. This is important in places like intensive care units or when a patient is under anesthesia having an operation.
This is a painful and invasive procedure and there needs to be a good reason for collecting this information. Patients who have their arterial blood sampled while they are awake describe the sensation as akin to having a needle stuck directly into their bone. Unfortunately, because one of the circumstances in which this information is important is while a patient is under an anesthetic, so the poor patient has to have the needle inserted while they are still awake.
Pulse oximeters are used a lot in research. Oxygen saturation is one of the parameters that is measured as part of sleeping studies that are investigating whether an individual suffers from sleep apnea, a condition where they stop breathing for brief periods during the night. This is a potentially fatal condition because it can lead to heart attack or stroke. At the very least, it makes people sleepy and unproductive the next morning.
There are two categories of sleep apnea, neurological and obstructive. Obstructive sleep apnea (OSA) is more common than neurological sleep apnea, but no less dangerous. Treatments may include a device that is prescribed by a dentist to keep the mouth partially open at night, continuous positive airway pressure (CPAP) or, in extreme cases, surgery to correct an anatomic deformity that makes the airway unable to open.
Central, or neurological sleep apnea, is less common and harder to treat than OSA. Instead of stopping the breathing process, the brain doesn't attempt it. There is often a serious condition underlying neurological OSA that affects the brain stem. This is the brain area that is responsible for breathing and heart rate. Neurological sleep apnea can happen by itself or in combination with OSA.
Although anyone can have any type of sleep apnea, the major risk factors are male gender over the age of 40 and being overweight. Sleep apnea is particularly dangerous in infants, who can stop breathing for as long as twenty seconds. This is a very daunting prospect for new parents. Fortunately, there are apnea alarms available that will alert the parents when a baby stops breathing for a set number of seconds. It is also possible to obtain CMS pulse oximeters for home use.
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