Hi,
Welcome to the ehealthforum and I am really glad to help you out. In view of your symptoms i.e. frequent blackouts, you need detailed evaluation of your cardiac and neurological systems.
These events could be because of a disturbed rhythm of the heart or possibly vasovagal syncope in which there is black out because of the increased activity of the vagus nerve which can cause sudden slowing of the heart beat.
You might need tests like 24 hr ECG monitoring(HOLTER) or turn table test for further confirmation of the same. I would suggest you to consult a cardiologist/ neurologist.
I sincerely hope that helps. Take care.