I wonder if they sedate them?
Interesting idea. With scuba you have all sorts of blood chemistry/gas saturation things to be wary of that are affected by depth and duration and one can imagine that medication could seriously complicate things. But yeah - anxiety, panic attacks, hyperventilation etc all big risks.
Chances are sedation under medical care would be a LOT safer than someone having a panic attack in a small space. I am not talking knocking them out, I am talking about something like tramadol which leaves you concious, but in a semi sleepy state.
Whilst I am sure the people doing the rescues understand the risks, it's dangerous for the rescuers if the person being rescued has a panic attack.
Lets not give an opiate with respiratory depressant effects (and minimal anxiolytic effects) to a child. (FDA has use in under 12 contraindicated because of concerns about genetic polymorphisms and variable response in young people)