Can caffiene be detected in the bloodstream?

Factual Questions
1

I dont do caffiene, me and caffeine DO NOT get along.

Tonight in a restaurant I ordered DECAF coffee, like I always do. However, shortly after consuming the beverage
it was obvious that I had drank regular coffee. I was PISSED, still am actually… I was EXTREMELY irritable and anxious due to the coffee. If this ever happens again
I would like some proof.
There are a lot of medical conditions that caffiene can aggravate and it seems to me that if one specifically requests DECAF, they should be able to safely assume that is EXACTLY what they will get.
Isnt their something called the Public Trust?
When I order a steak, I expect a COW steak, NOT a hunk of buffalo.
So anyway, back to the original question.
Thanks

2

I’m sure it can be, just as many other drugs.

There’s probably not a standard test set up for it (they’ve never asked for a blood-caffeine content on ER). But if you’re willing to pay the bucks, I’m sure a medical lab would be willing to draw your blood and test for caffeine.