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Intermediate Technical IVT

Near-Infrared Spectroscopy

Also written as: NIRS — Near-Infrared Spectroscopy

Non-invasive optical technique for monitoring regional cerebral oxygen saturation using near-infrared light.

Full Definition

Near-Infrared Spectroscopy (NIRS) is a non-invasive monitoring technique that uses near-infrared light to measure regional cerebral oxygen saturation (rSO2) in the frontal cortex. NIRS sensors placed on the forehead detect changes in oxygenated and deoxygenated hemoglobin concentrations, providing real-time information about cerebral oxygenation. Normal rSO2 values range from 60-80%, with decreases below 50% or reductions greater than 20% from baseline considered clinically significant. This technology is particularly valuable during cardiac surgery, neurosurgical procedures, and in neurocritical care for continuous cerebral oxygenation monitoring.

Usage

Usage note: Specify whether bilateral or unilateral monitoring when documenting.

In Context

  • "Near-infrared spectroscopy revealed a significant drop in regional cerebral oxygen saturation to 45% during the hypotensive episode." — Intraoperative monitoring report

Also known as

NIRS cerebral oximetry

Don't confuse with

pulse oximetry jugular venous oxygen saturation

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