I read your question and I understand your concern. Confusion and feeling of passing out can be a seizure manifestation. It is not clear whether he had any tests done after his first seizure (from your description a generalized seizure). Seizures in an adult must be investigated after as usually there is a cause behind them. So apart from some routine blood tests he should have examination with MRI to look for brain lesions (tumor, stroke, infection etc) and EEG to search for epileptic activity, location and type. Other exams may be needed at times depending on the physical and imaging exams findings. The fact that he s having these episodes reinforces the need for more exams. Treatment will be directed towards the cause and anti-epileptic treatment if necessary. The lack of oxygen described to you has been suggested as a result of the generalized seizure with temporary breathing interruption, as a secondary sign, not as a cause of the seizure. I hope to have been of help.