Table 1 Causes and types of cerebral hypoxia
From: “THE MANTLE” bundle for minimizing cerebral hypoxia in severe traumatic brain injury
CBF | PtiO2 | LPR | OEF | Pathophysiology | |
|---|---|---|---|---|---|
Ischemic | ↓ | ↓ | ↑ | ↑ | Inadequate CBF |
Low extraction | ≅ | ↓ | ↑ | ≅ | Low arterial partial pressure of oxygen, PaO2 (hypoxemic hypoxia) |
Low hemoglobin concentration (anemic hypoxia) | |||||
Low half-saturation pressure P50 (high- affinity hypoxia) | |||||
Shunt | ↑ | ≅ | ↑ | ↓ | Arteriovenous shunting (microvascular shunt) |
Diffusion | ≅ | ≅ | ↑ | ↓ | Diffusion barrier (intracellular or interstitial edema) |
Uncoupling | ≅ | ≅ | ↑ | ↓ | Mitochondrial dysfunction |
Hypermetabolic | ↑ | ↓ | ↑ | ↑ | Increased demand |