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Pulse Oximetry Uses and Abuses: Accuracy

The measurement of oxygen saturation by the COoximeter is the standard by which pulse oximetry is calibrated. An early study by Yelderman and New examined the accuracy of pulse oximeters over the range...

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Pulse Oximetry Uses and Abuses: Limitations (1)

Although pulse oximetry represents a significant advance in noninvasive monitoring, situations exist where the pulse oximeter may give misleading or inaccurate information, as shown in the following...

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Pulse Oximetry Uses and Abuses: Limitations (2)

Dyshemoglobinemias The presence of dyshemoglobinemias may lead to erroneous pulse oximetric measurements. A review of some published experimental and clinical data helps elucidate the effects of...

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Pulse Oximetry Uses and Abuses: Limitations (3)

Methemoglobin also interferes with the accurate reporting of oxyhemoglobin by the pulse oximeter. Methemoglobin is formed when the iron in hemoglobin is oxidized from the ferrous to the ferric state....

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Pulse Oximetry Uses and Abuses: Limitations (4)

At higher methemoglobin levels, the pulse oximetry saturation became independent of methemoglobin levels. The absorption characteristics at the two measured wavelengths provide an explanation for this...

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Pulse Oximetry Uses and Abuses: Limitations (5)

Dyes A number of dyes and pigments interfere with the accuracy of the pulse oximeter;” for example, methylene blue, the treatment for methemoglobinemia, will affect pulse oximetric readings. Methylene...

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Pulse Oximetry Uses and Abuses: Limitations (6)

Anemia Severe anemia can affect the pulse oximeter, since the reading depends on light absorption by hemoglobin. Generally, this is not of clinical significance until the hemoglobin level is less than...

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Pulse Oximetry Uses and Abuses: Limitations (7)

Miscellaneous Excessive light from a number of sources, including surgical lamps, infrared lamps, bilirubin lamps, or even direct sunlight, can interfere with oximetric accuracy. If too much light is...

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Pulse Oximetry Uses and Abuses: Clinical Settings (1)

The use of pulse oximetry in the operating room and the recovery room have become the standard of care. Standards for monitoring during anesthesia set up by the Harvard Medical School System now...

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Pulse Oximetry Uses and Abuses: Clinical Settings (2)

Development of hypoxemia during the procedure correlated with a low baseline oxygen saturation, the duration of the procedure, and prior left ventricular function. Bronchoscopy is known to produce a...

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