Liposuction is a relatively safe surgery and there are no long term serious side effects.
Improvements in Liposuction technique over the last five decades and use of smaller cannulae have resulted in vastly improved results with increased safety.
Swelling, soreness, bruising, numbness are to be expected in the initial few weeks. Serious complications like loss of skin, deep vein thrombosis, fluid overload and organ damage are extremely rare when safety measures are properly instituted. The chance of having an adverse outcome is more in medically compromised patients like people with uncontrolled diabetes, high blood pressure and in heavy smokers. Long duration of surgery and very large volumes of Liposuction also increase the chance of some of the complications.
Fluid collections or seroma can occur in the initial few weeks after surgery in less than 5% cases, and this can be treated well by aspirating the collected fluid.