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Updated: Jul 11, 2026
09:54
A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Transient global amnesia after breathing hyperoxic mixtures in otherwise regular dives
Fabio Spigno1, Massimo De Lucchi, Luca Migliazzi
1Department of Occupational Medicine, University of Genova, Genova, Italy.
Clinical Neurology and Neurosurgery
|October 9, 2007
Summary
Transient global amnesia (TGA) is a rare adverse effect of breathing hyperoxic mixtures during diving. This case report highlights TGA as a potential, previously undocumented neurological symptom following otherwise safe dives.
Area of Science:
- Neurology
- Diving Medicine
- Hyperbaric Physiology
Background:
- Decompression sickness diagnosis can be challenging, especially with atypical presentations.
- Divers breathing hyperoxic mixtures (Nitrox) may experience neurological dysfunction.
Observation:
- Two divers experienced transient global amnesia (TGA) immediately after uneventful dives using Nitrox.
- No prior literature documented TGA as an adverse effect of hyperoxic gas breathing.
Findings:
- Transient global amnesia (TGA) is reported as a potential neurological complication of hyperoxic gas exposure during diving.
- The mechanism of TGA in this context is unlikely to be epileptic.
Implications:
- Clinicians should consider TGA in divers presenting with acute memory loss after hyperoxic dives.
- This finding expands the spectrum of known neurological risks associated with hyperoxic gas mixtures in diving.
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