What's the "safe" amount of fat to remove in patients undergoing liposuction? Rather than a hard-and-fast rule, the answer depends on the patient's body mass index (BMI), according to a report in the September issue of Plastic and Reconstructive Surgery®, the official medical journal of the American Society of Plastic Surgeons (ASPS).

"Our study shows that liposuction is associated with a very low complication rate, with major complications occurring in less than 1 in 1,000 patients," comments ASPS Member Surgeon John Y.S. Kim of Northwestern University, Feinberg School of Medicine, Chicago. "It also calls into question the concept of simple absolute thresholds for lipoaspirate volume—the amount of liposuction that can be performed safely seems to depend in part on how much fat content a person begins with."

Study Proposes 'Relative Liposuction Volume Threshold' Based on BMI

There's a long history of debate over the safe volume of fat tissue that can be removed by liposuction. Current ASPS guidelines define 5,000 milliliters (five liters) as "large-volume liposuction" potentially associated with a higher risk of complications. But the guidelines acknowledge there is no scientific data to support an absolute cutoff point.

Dr. Kim and colleagues analyzed data on more than 4,500 liposuction patients, drawn from the ASPS's "Tracking Operations and Outcomes for Plastic Surgeons" (TOPS) database. They evaluated the relationship between liposuction volume and complication risk—including interactions with the patient's BMI.

The overall complication rate was 1.5 percent, with few serious complications and no deaths. By far, the most common complication was a fluid collection (seroma) requiring drainage. The average liposuction volume was about two liters.

Patients with complications had larger liposuction volumes—average 3.4 liters—and higher BMIs. Patients undergoing "large-volume" liposuction of more than five liters had a higher overall complication rate: 3.7 versus 1.1 percent. This resulted almost entirely from an increase in seromas.

There was also a significant interaction between liposuction volume and BMI: when patients with higher BMIs had a greater liposuction volume, the complication rate was actually somewhat lower.

"In other words, obese patients may tolerate larger lipoaspirate volumes without an increased risk of complications," the researchers write. In contrast, patients with lower BMIs experience a "more exponential increase in risk" at higher liposuction volumes. This relationship between a patient’s pre-existing fat content and "safe" liposuction volumes had not been previously shown.

Dr. Kim and colleagues introduced the concept of a "relative liposuction volume threshold" based on BMI. Dr. Kim and co-researcher Dr. Karol Gutowski emphasized that this provides a relative threshold where complications start to increase, but does not imply an absolute limit on liposuction volumes. Other considerations such as length of surgery, adjunct procedures, and the patient's overall health status are also important to consider when evaluating liposuction risk.

"Our risk assessment tool can further aid shared decision-making between the surgeon and patient by linking BMI and liposuction volumes," adds Dr. Kim.

Dr. Gutowski, who is also a member for the ASPS Patient Safety Committee and past Chairman of the ASPS Quality & Performance Metrics Committee, points out that these finding are only possible due to the surgery data contributed by Board-certified plastic surgeons. "By developing the TOPS database, ASPS is leading the way in safe and effective plastic surgery which benefits both patients and plastic surgeons," he comments.

Plastic and Reconstructive Surgery® is published by Wolters Kluwer.

About Plastic and Reconstructive Surgery

For more than 60 years, Plastic and Reconstructive Surgery (PRS)® has been the one consistently excellent reference for every specialist who uses plastic surgery techniques or works in conjunction with a plastic surgeon. The official journal of the American Society of Plastic Surgeons, PRS brings subscribers up-to-the-minute reports on the latest techniques and follow-up for all areas of plastic and reconstructive surgery, including breast reconstruction, experimental studies, maxillofacial reconstruction, hand and microsurgery, burn repair, and cosmetic surgery, as well as news on medico-legal issues.

About Wolters Kluwer Health

Wolters Kluwer Health is a leading global provider of information, business intelligence and point-of-care solutions for the healthcare industry. Serving more than 150 countries and territories worldwide, Wolters Kluwer Health’s customers include professionals, institutions and students in medicine, nursing, allied health and pharmacy. Major brands include Health Language®, Lexicomp®, Lippincott Williams & Wilkins, Medicom®, Medknow, Ovid®, Pharmacy OneSource®, ProVation® Medical and UpToDate®.

Wolters Kluwer Health is part of Wolters Kluwer, a market-leading global information services company. Wolters Kluwer had 2012 annual revenues of €3.6 billion ($4.6 billion), employs approximately 19,000 people worldwide, and maintains operations in over 40 countries across Europe, North America, Asia Pacific and Latin America. Follow our official Twitter handle: @WKHealth.

About ASPS

The American Society of Plastic Surgeons (ASPS) is the world's largest organization of board-certified plastic surgeons. Representing more than 7,000 Member Surgeons, the Society is recognized as a leading authority and information source on aesthetic and reconstructive plastic surgery. ASPS comprises more than 94 percent of all board-certified plastic surgeons in the United States. Founded in 1931, the Society represents physicians certified by The American Board of Plastic Surgery or The Royal College of Physicians and Surgeons of Canada. ASPS advances quality care to plastic surgery patients by encouraging high standards of training, ethics, physician practice and research in plastic surgery. 

Contact ASPS

Media Relations
(847) 228-9900
media@plasticsurgery.org