cerebral oxygen extraction fraction
The percentage of delivered oxygen that brain tissue extracts from arterial blood, calculated as OEF. Key indicator of cerebral metabolic demand relative to oxygen delivery.
Full Definition
Cerebral oxygen extraction fraction (OEF) represents the proportion of oxygen delivered to the brain that is actually consumed by cerebral tissue, typically expressed as a percentage. Normal OEF is approximately 30-40%. It is calculated as the difference between arterial and venous oxygen content divided by arterial oxygen content. OEF provides insight into the balance between oxygen supply and demand in the brain. Elevated OEF may indicate inadequate oxygen delivery or increased metabolic demand, while reduced OEF might suggest luxury perfusion or decreased metabolic activity. This parameter is particularly valuable in managing patients with cerebrovascular disease, traumatic brain injury, and other conditions affecting cerebral metabolism.
Usage
Usage note: Often abbreviated as OEF. Editors should ensure consistency between spelled-out and abbreviated forms within documents.
In Context
- "The elevated cerebral oxygen extraction fraction suggested impaired oxygen delivery despite normal perfusion pressure." — Neurocritical care consultation
- "OEF monitoring revealed improved cerebral oxygenation following treatment optimization." — Clinical case report