Which of the following is a limitation of pulse oximetry?

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Multiple Choice

Which of the following is a limitation of pulse oximetry?

Pulse oximetry estimates arterial oxygen saturation by passing red and infrared light through a perfused tissue and measuring how much light is absorbed by oxyhemoglobin and deoxyhemoglobin. A real limitation is nail polish, especially dark or thick coats, because the pigments absorb light at the wavelengths the device uses. This interferes with the optical signal and can yield inaccurate readings or make it hard to obtain a reading at all. Removing nail polish or using another measurement site improves accuracy. Reading from an arterial blood gas is a different method that provides direct blood gas values; it isn’t a limitation of pulse oximetry. Movement can cause artifact and unreliable readings, so the statement that it isn’t affected by movement is incorrect. Instant feedback is an advantage of pulse oximetry, not a limitation.

Pulse oximetry estimates arterial oxygen saturation by passing red and infrared light through a perfused tissue and measuring how much light is absorbed by oxyhemoglobin and deoxyhemoglobin. A real limitation is nail polish, especially dark or thick coats, because the pigments absorb light at the wavelengths the device uses. This interferes with the optical signal and can yield inaccurate readings or make it hard to obtain a reading at all. Removing nail polish or using another measurement site improves accuracy.

Reading from an arterial blood gas is a different method that provides direct blood gas values; it isn’t a limitation of pulse oximetry. Movement can cause artifact and unreliable readings, so the statement that it isn’t affected by movement is incorrect. Instant feedback is an advantage of pulse oximetry, not a limitation.

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