For what its worth: at the time of my post-op hospital discharge, I was asked (by a nurse) if I'd had a BM since the surgery. At the risk of my freedom from hospital captivity being delayed as we waited for my bowels to move - a daunting thought - I bravely and honestly answered "no". Fate smiled and I was discharged anyway, with the suggestion to use a laxative if I didn't have a BM within 48 hours. Fortunately, now in familiar surroundings and eating food fit for human consumption, I experienced the highly-anticipated BM within the requisite 48 hours. My wife congratulated me, which made me feel like I was 2 years old - but I amiably accepted her kudos, knowing that she meant well. My digestive system apparently re-set itself and operated normally from that point forward. Apparently, this is not always the case for every post-op AN patient. The various suggestions posted for getting things moving again seem valid and should work.
Jim