What cause short sudden onset of inability to breathe, other than short intake of air at intervals,?

I experience what you describe during panic attacks. If you usually have the shortness of breath or complete pauses when you think about something that makes you sad, stressed, or anxious, or when you are in a situation of these sorts, it could be a panic attack causing it. But you should go see a specialist to figure out what is the cause.

Hello Anon

Thank you for writing.

There could be numerous reasons for shortness of breath, including a heart or lung condition (including asthma) or even an allergy to something. A panic attack can also restrict the ability to breathe.
If you have experienced an inability to breathe, consult your doctor - this is not something you should ignore.

Best,
Susan