WHAT?!?! They let you wear an awesome and spiffy hat such as that during your surgery?
All they gave me was a robe that functioned as clothes and a peep show from behind.
Lucky you sir, lucky you!
P.S. Get better soon.
P.P.S. Did they happen to miss your vein?
P.P.P.S. Because that's exactly what happened to me during one of my surgeries :/