You are not a good candidate for a tummy tuck at your current BMI. You are at much greater risk for lung problems, wound healing problems, blood clots, infection etc, etc. The risk is not worth the probably minor improvment you will get with surgery.
The only exception to this is if you have a large panniculus which causes a lot of problems with skin irritation and mobility. In that case you may be a reasonable candidate for a panniculectomy which just removes the redundant folds of fat and skin but does not shape the abdomen.
At your current BMI, you have likely failed at every diet known to mankind. You may want to explore bariatric surgery. I have operated on so many people who finanlly were able to control their eating with
Seattle Plastic Surgery, Lisa Lynn Sowder, M.D.