I use about 60cc's of 0.5%Xylocaine with 1/200,000 Adrenalin and 1 ampule of hyaluronidase(Wydase). I infiltrate as I go, taking care to block the ilioinguinal, iliohypogastric, genitofemoral nerves witha couple of cc's each, as well as the pubic tubercle, and the rest around the peritoeum of the sac. Formal blocks are unnecessary, and with experience, infiltration as you go along seems to work in all but the largest incarcerated ones, in which case spinal or epidural is better. Secondly, even though the Barium enema shows an apparently normal mucosa, and it is unlikely to harbour a carcinoma, granulomatous colitis is another possibility. Every so often a diverticulitis resection turns out to have Crohn's of the sigmoid, especially in a 39 yr old.