There are more risks with liposuction due to the fat and its surrounding tissues becoming necrotic (dead tissue). If the fat becomes necrotic from lack of blood supply, the fat tends to turn orange-ish clear and drain from the incision. If the tissue becomes necrotic, that's a completely different story. You must have the tissue removed before a major infection develops, possibly causing gangrene. Even with the ultrasonic technique, patients have been known to receive actual burns from the ultrasonic technique. The fat is actually melted within the body by 'exciting' the fat molecules with high frequency radio waves and is suctioned out. There may be asymmetry, hyper-pigmentation (permanent dark spots) from the bruising. Major blood loss is a factor is some cases. As is hematoma and infection. Liposuction is NOT the way to lose weight.
Another risk of liposuction* is pulmonary Thromboemboli. A thromboebolus is a blood clot and this blood clot can break free and travel to the lungs resulting in pulmonary Thromboemboli. This can put a patient into adult breathing distress and subsequently into cardiac arrest or coma - leading to the patient becoming 'brain dead' shortly thereafter or in a vegetative state from loss of oxygen to the brain. Pulmonary Thromboemboli can happen within three weeks of the surgery but will most likely show symptoms of shortness of breath and fatigue within the first 72 hours. However, pulmonary Thromboemboli can occur suddenly, without warning. Most patients with P.E. collapse and begin rapid deterioration after attempting to climb a flight of stairs.
*facial liposuction risks are far less than body liposuction due to the amount of fat that is suctioned and disrupted.