Pulse oximetry: what the nurse needs to know
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Pulse oximetry: what the nurse needs to know

Rebecca Myatt Nurse case manager (thoracic surgery), Guy’s Hospital, Guy’s and St Thomas’ NHS Foundation Trust, London, England

Rationale and key points

Measurement of peripheral oxygen saturation (SpO2) is used to identify early hypoxia in patients and evaluate the effectiveness of oxygen therapy. Nurses should be aware of the procedure for using a pulse oximeter to measure SpO2 levels and the normal range for SpO2 readings.

A pulse oximeter is used to measure SpO2 levels, and involves placing a probe on the patient’s finger, toe or ear lobe.

A SpO2 level of less than 90% is a clinical emergency. If the SpO2 level is below 94%, the nurse should assume the patient is hypoxic until proven otherwise, and therefore they may require supplemental oxygen administration.

Nurses should be aware of the factors that might affect SpO2 readings, including anaemia, peripheral vasoconstriction, dark skin tone and skin discolouration.

Nursing Standard. 31, 31, 42-45. doi: 10.7748/ns.2017.e9940



Peer review

This article has been subject to external double-blind peer review and checked for plagiarism using automated software

Conflict of interest

None declared

Received: 25 January 2015

Accepted: 16 July 2015

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