I hadn't thought about a bouyancy change - I'll take a look once I get back diving, since I have logged my exposure protection, gear and lead consistently since I started diving. If you don't hear back from me on that, assume no change.
Well, I am now 4 weeks post-op and feeliing much better, especially in the last 3 days. I have the chevron incision through all the ab muscles - I look as though a Mercedes-Benz ran into me - but didn't have to have transfusions (they had reserved 4 units of blood for me).
The post-op instructions say no lifting for 3 months of anything heavier than a large purse. Since I figure the scuba gear I use for temperate water beach dives weighs closer to 50 -70 pounds, depending, I wasn't sure how long the FULL recovery will take.
I was fairly good shape before the surgery, except for overweight. The week prior to surgery I was doing a non-contact tae dwon do workout that included 50-plus sit-ups and 20 push-ups, and I could keep up with most of the black belts, so my abs had a good baseline. One or two days after the surgery, they sent a physcial therapist around to get me up and walking, and she seemed surprised and impressed at my ability to get up from the hospital bed and do laps, albeit very slowly, around the floor. So, my recovery is doing well in that area. Now that I am home from the hospital, I'm taking a couple of walks around the (very flat) neighborhood for a little bit further every day. I am not happy with my performance with the spironometer yet, and deep breaths are still uncomfortable. In the last four days, I have recovered the ability to inhale deeply enough to yawn comfortably, but not to sneeze properly. So, I'm making progress daily, and am happy with that.
Resection was for removal of 2 tennis-ball sized masses and one smaller one, all of which turned out to be non-malignant. Yippee!