oxygen saturation
The percentage of haemoglobin molecules in arterial blood that are bound to oxygen, measured non-invasively by pulse oximetry (SpO₂) and used as a primary monitoring parameter during dental sedation.
Full Definition
Oxygen saturation expressed as SpO₂ is a cornerstone monitoring variable in dental anesthesiology, with accepted thresholds typically set at ≥95% for sedated patients and ≥92% as an intervention trigger. The subscript 'p' in SpO₂ denotes peripheral, non-invasive pulse oximetry measurement, distinguishing it from SaO₂ (directly measured arterial saturation). Editors reviewing sedation protocols and monitoring documentation must ensure SpO₂ is consistently formatted with a subscript '2' and a lowercase 'p', and that it is distinguished from SaO₂. The Bezold–Jarisch reflex and nail polish/dark skin considerations may appear as confounding discussion points in manuscripts.
Usage
Usage note: Use 'SpO₂' (with subscript numerals) when abbreviating after first use. Do not conflate SpO₂ (non-invasive) with SaO₂ (invasive arterial blood gas measurement).
In Context
- "The patient's oxygen saturation dropped to 91% during the procedure, prompting supplemental oxygen delivery and repositioning of the airway." — Sedation incident report
- "Continuous SpO₂ monitoring is required from the time of drug administration until the patient meets discharge criteria." — Office-based sedation policy