Lack of Drainage After Liposuction?

Liposuction is a closed procedure, as such it does not require drainage.
When done with small cannulas, there are no large continuous cavities where lakes of fluid, or seromas, can accumulate. I don't know any surgeon that drains liposution with drains.
As far as leaving the incisions open, practices vary. I personally put two staples on each incision just to help it heal faster, but it still drains thru a little bit. I inject a lot of tumescent fluid, but frankly, I like to leave that fluid in as a reservoir of fluid for the patient to reabsorb over the next few days.
The best way to deal with the swelling is compression garments in combination with compression pads (Topifoam). This has the advantage of drastically reducing bruising.
When compression garments and pads are not used, it is not uncommon for the tissues to appear swollen for a while. At 12 days, It is too early to make a judgement. Do make your concerns known to your surgeon.
Check out the link below for a more in depth discussion of swelling post op.

Hello,
I loosely close my liposuction incisions and they drain for only a day or two. Swelling is pretty normal whether or not you drain much as some doctors inject more tumescent solution than others. Swelling is seen as the remaining fat responds to the procedure.
As you can see some of this depends upon the technique your doctor used and you might be better off addressing your concerns with him or her. Small liposuction cases do not look much changed right afterward until the swelling resolves.

Hi.

At 12 days, I would not worry unless you have hard lumps.  We leave the incisions open, but many plastic surgeons close them