Is Liposuction Necessary when Having Tummy Tuck?

There are many issues here which are too complex to answer completely in this format but I will try to simplify.

Some physcians have concerns with any combination of the procedures and feel that there is an elevated risk of deep venous thrombosis. This, at one time in the past, let the Florida State Health officials to limit performing these combinations to hospitals or surgery centers only; this moratorium has since been lifted.
Many physicians are reluctant to perform liposuction on areas that are lifted during the surgery especially the central and upper portions of the belly. This can cause a compromise of the blood supply and lead to healing problems. Less controversial is liposuction of the flanks (an area that is not lifted). Liposuction of the thighs, arms etc. is generally considered acceptable but does vary among surgeons and may depend on the extent of the abdominoplasty.
Liposuction is generally considered an integral part of mini-abdominoplasty in which the upper and central parts of the abdomen are not lifted up.

This is extremely oversimplified and is essentially a summary of the most relevant points in my opinion. I hope it helps.

There is some controversy about lipo at the time of abdominoplasty. If done with caution and not to and undermined flap I feel as if it can be done safely. Whether or not it is neccessary depends upon where you have fatty excesses. In some cases if they are not addressed at your initial surgery you might need to have it done later to maximize your result.
Just address your concerns with the plastic surgeon that you like the best and I'm sure he/she can put your mind at ease.
Good Luck!