"OK Dad, I'm going to untie you now. Do not touch your head, and do not pull on any tubes or wires, OK?"
"Do you understand what I just told you Dad? Two things: Don't touch your head, and don't pull on anything."
He turned his head and gave me that "WTF, do you think I'm stupid" look.
"Of course not."
I untied him and he let his hand stretch out a moment. He let out a big sigh, quickly and squishily poked his skull-free zone, and then smiled.