Why don't some doctors use drains after lipo and BBL procedures?

Drains are not typically required for liposuction or Brazilian Buttlift procedures.  The critical structures called lymphatics are not cut with liposuction.  Instead, the fat is suctioned leaving behind the lymphatics intact.  Drains can help with more aggressive liposuction with ultrasound, large volume liposuction or surgery (such as a tummy tuck) combined with liposuction. The drain(s) wick out the tumescent fluid that makes liposuction safe and the swelling fluid into a bulb to minimize the fluid collecting under the skin.  Short answer- drains are not usually required for procedures such as liposuction.  Best Wishes!!   

There is no indication for drains in liposuction. As matter of fact, I'm not even sure how you could get them in after properly perform liposuction.

There is no need for them.  There is no evidence they help and they can increase risk of infection as well.  Best, Dr. Emer.