Tuesday in pre-op for a colonoscopy, my systolic BP was 185, in the operating room it was 161, following an after noon nap it was 120. I believe BP measurements should be a "resting" average, so is it correct to disregard the two highest numbers?
To diagnose hypertension one needs to have two separate measurements done at two different times. You probably have hypertension, but you have given me too little information. See your doctor in the office and see what your pressure runs around; if its over 140 systolic on two separate measurements, then you will need treatment and/or lifestyle modification (salt restriction and aerobic exercise).
I would imagine that your BP was up due to anxiety, and down later due to relief of stress and also the drugs given during the procedure. IMO, they would all be kind of artificial readings and I would pay attention to those taken during a routine day. But I am not a physician.