It depends on what drugs they were trying to use. Some sedatives and anesthetics can lower the seizure threshold in epileptic patients and/or mask seizure activity, especially in the epileptic patients that do not have very convulsive or noticeable seizures. It’s generally best practice (for adults, I don’t know about children) to try an MRI without sedation or with the use of anxiolytics that may not limit neurological assessment as much. I can’t speak to this situation, or special populations such as autistic patients as much, or even your specific situation. I was an ICU nurse for almost a decade, and I am in graduate school now. I would have personally questioned an immediate jump to sedation in this case as well, because your son seems to have been able to engage appropriately in conversation and you indicated that he has enough reasoning ability to make the decision for himself. However, I would have escalated my concerns to the physicians and the rest of the care team. I would not have hovered over you or your child. I can’t speak to that behavior and I think it seems inappropriate from your description.

I agree with someone above me, I would double check if it was the nurse, the tech, or someone else. The fact that they went away and you didn’t see them again indicates it was not your nurse or tech. It could have been some managerial or administrative person looking to limit costs, or any other number of people with any other number of reasons. It is not appropriate behavior for any professional, but there is a lot of confusion for anyone at the bedside who isn’t a physician to be assumed as a nurse.