cerebral oximetry
Non-invasive monitoring of regional brain oxygen saturation using near-infrared spectroscopy.
Full Definition
Cerebral oximetry employs near-infrared spectroscopy (NIRS) to continuously monitor regional cerebral oxygen saturation (rSO2) by measuring the ratio of oxygenated to total hemoglobin in brain tissue. This monitoring is particularly valuable during cardiac surgery with cardiopulmonary bypass, where cerebral perfusion may be compromised. Normal rSO2 values range from 60-80%, and decreases of more than 20% from baseline or absolute values below 50% may indicate cerebral hypoxia requiring intervention such as increased pump flow, blood pressure support, or fraction of inspired oxygen adjustment.
Usage
Usage note: Include baseline and threshold values when documenting cerebral oximetry changes.
In Context
- "Cerebral oximetry showed bilateral rSO2 values declining to 45% during deep hypothermic arrest." — Intraoperative monitoring report
- "The protocol requires cerebral oximetry monitoring for all patients undergoing aortic arch procedures." — Surgical care guideline