I will note that general anaesthesia generates lots of extra billable hours (anaesthetist! extra nurse/assistant anaesthetists!), which might be why US hospitals are so keen on it and NHS hospitals are less so.
This may sound like a strange sentiment, but years ago I broke a bone on a weekend and they put my arm in a sling at the emergency room. I got to see a doctor on monday and he said - you have to move your arm. "Move it every day, otherwise you will lose your range of motion. Let pain be your guide".
Completely different advice than I expected (I expected to keep it immobilized as much as possible until fully healed)
So I wonder if I was knocked out - would they damage something while they're looking around without my hints?
There are risks to colonoscopy, primarily in older patients. You can get a perforated bowel.
Quite plausible that where sedation is warranted this reduces the risk. But that would depend upon whether the cause of this perforation is even amenable to patient/doctor feedback.
They asked me if I wanted to watch, then angled one of the monitors so I could see what they were doing. Laid on side, knees up and relax. Blimely is my bum really that hairy? Don't normally get to see if from that angle.
It feels weird and a little uncomfortable at times, but certainly not painful - even when they found a polyp and removed it with a remote lasso tool of some kind. This later turned out to be harmless.
As is normal for Brits, there was a lot of humour, with the women discussing the latest TV soap opera whilest doing their thing with the "dynorod" tool. As they pump in a gas of some kind to keep the bowl inflated while they work, they tell me it's okay to fart whenever I need. Boy, I think I've got a bad job sometimes. Whatever the nurse with the pointy end gets paid - it's not enough.
It's not exactly pleasant, but necessary and quite interesting to watch inside your own body (not as interesting as watching surgeons put stents into my heart, but that's another story).
Totally agree with Graeme, nothing to fear and massive win if they find things before it's too late. Don't hesitate!