Transient global amnesia (TGA)

Developed in collaboration with CASA Medical.

Transient global amnesia (TGA) is a clinical syndrome characterised by the sudden onset of anterograde amnesia, accompanied by repetitive questioning, sometimes with a retrograde component, lasting up to 24 hours, and without compromise of other neurologic functions. Ability to do routine tasks often remains intact despite during the episode of anterograde amnesia.

In many cases there are no known precipitating factors but some episodes of TGA have identifiable triggers such as:

• painful experience
• emotional stress
• physical exertion
• acute illness
• cold or hot water immersion
• sexual intercourse
• raised intrathoracic pressure such as during Valsalva or high-G manoeuvres.
• medical procedures

TGA is a medical condition of safety relevance or aeromedical significance.

Pilot and controller information

• If pilots or controllers suspect they might have or have been diagnosed TGA they must ground themselves or stop operating immediately.
• Pilots and controllers must obtain a ME review or contact CAA NZ AvMed for further advice

For more information, see Medical Manual: Transient global amnesia.