Gluteal fat grafting: What’s going wrong?
Gluteal fat grafting – augmentation with autologous fat – is among the fastest growing aesthetic procedures in both the United States and increasingly around the world.
Despite the growing popularity, significantly higher mortality rates appear to be associated with gluteal fat grafting than with any other aesthetic surgical procedure.
Amid worrying anecdotal and published reports of both fatal and non-fatal pulmonary fat embolism resulting from this procedure, the US Aesthetic Surgery Education and Research Foundation (ASERF) formed a Task Force (of 11 surgeons, pathologists and statisticians) to study this complication, led by Dr Mark Mofid, MD, FACS (chair) and Dr Steven Teitelbaum, MD, FACS (president).
In January this year, the Task Force published its important findings and recommendations, titled ‘Report On Mortality From Gluteal Fat Grafting’, in the Aesthetic Surgery Journal.
Rapidly increasing demand
The past two decades have witnessed extensive growth and interest in body contouring. The buttocks are no exception.
The rise in popularity of gluteal fat grafting (often commonly referred to as ‘Brazilian butt lifts’) coincides with Western culture’s recent infatuation with big and curvaceous buttocks – as seen on social media influencers and celebrities such as the Kardashians.
The ASERF Task Force reported the demand for the procedure “has increased dramatically over the last five years”. According to statistics from the American Society for Aesthetic Plastic Surgery (ASAPS), “core physicians” (plastic surgeons, dermatologists and facial plastic surgeons) performed 18,487 of these procedures in 2015 compared to 7382 in 2011. In addition, “as many as 25% more are performed by non-core physicians” – resulting in more than 23,000 procedures performed in the US last year.
The popular consumer website RealSelf reported that in 2015 there were 7.2 million visits to buttock augmentation pages – a 32% increase from 2014. (This number of visits was exceeded only by enquiries into breast augmentation.)
However, there have also been increasing reports about the potential risks involved – highlighted by international headlines which accompanied incidents such as the death of high-profile former Miss Argentina Solange Magnano at age 38, three days after surgery “following complications from a gluteoplasty procedure to enlarge her buttocks”.
Task Force objectives
The ASERF Task Force set out to study the risks of both fatal and non-fatal pulmonary fat embolism (PFE) associated from gluteal fat grafting, as well as any potential variables affecting these risks and provide recommendations to decrease those risks.
A 15-question survey was sent in July 2016 to 4,843 plastic surgeons worldwide – 1,963 active members of ASAPS and 2,880 active members of the International Society of Aesthetic Plastic Surgery (ISAPS).
The survey probed surgeons about numbers of cases performed, depth and angulation of injection, size and type of cannulae used for grafting, access and approach used, and the number of fatal and non-fatal PFEs occurring over the last 12 months and over their career.
Additional data on morbidity and mortality was collected through confidential interviews with plastic surgeons and medical examiners, public records requests for autopsy reports in the US, and through the American Association for the Accreditation of Ambulatory Surgical Facilities (AAAASF).
Geographically, the respondents included USA/Canada 38%, South America 24%, Europe 15%, Mexico/Central America 11%, Middle East/North Africa 5%, Asia Pacific/Indian Subcontinent/Australia 4% and Other 3%.
PFE rate rising with ‘Butt Lift’ popularity
Globally, 692 surgeons responded to the survey (14.3%) and reported 198,857 cases of gluteal fat grafting. Over their careers, the surgeons reported 32 fatalities from pulmonary fat emboli (1 in 6,216) as well as 103 non-fatal pulmonary fat emboli (1 in 1,931).
The Task Force noted the calculated total rate of having either a fatal or non-fatal PFE over a career is therefore 1:1,473.
However, with the increasing popularity of the procedure, the Task Force also highlighted that over the previous 12 months, 574 surgeons reported performing 17,519 cases, with 5 fatal PFEs (for an annual mortality rate of 1 in 3,448) and 12 non-fatal PFEs (for an annual rate PFE rate of 1 in 1,449).
As a result, accompanying the increased worldwide popularity, the calculated total rate of both fatal and non-fatal PFEs in the last year has increased to 1 in 1,030 cases.
In sharp contrast, the Task Force noted that “the highest known mortality rate associated with an aesthetic procedure prior to this paper was abdominoplasty, with a mortality rate of 1:13,147, nearly all from pulmonary embolisms”.
Deep muscle injections significantly increase PFEs
Among the responding surgeons, 3% (18 individuals) had experienced a patient fatality and 7% (43 individuals) reported at least one non-fatal pulmonary fat embolism in a patient over their careers.
Importantly, no association was identified between surgeon experience and PFE.
However, surgeons reporting the practice of “injecting into the deep muscle experienced a significantly increased incidence rate of fatal and non-fatal pulmonary fat emboli”.
The Task Forced confirmed 25 fatalities in the US over the last 5 years through autopsy reports and interviews with surgeons and medical examiners. As well, four deaths were reported from 2014 to 2015 from pulmonary fat emboli in AAAASF (ambulance) facilities.
Higher death rate ‘than any other aesthetic surgical procedure’
The Task Force summed up its findings with a warning: “Despite the growing popularity of gluteal
fat grafting, significantly higher mortality rates appear to be associated with gluteal fat grafting than with any other aesthetic surgical procedure.
“Based on this survey, fat injections into the deep muscle, using cannulae smaller than 4mm and pointing the injection cannula downwards, should be avoided,” the report states.
The Task Force emphasised that “more research is necessary to increase the safety of this procedure” and to “identify techniques that avoid catastrophic complications”.
These may include peri-operative imaging to identify gluteal vessels in advance of fat injections, ideal incisional access locations, refined instrumentation, investigation into fat preparation, and pharmacologic veno-constriction.
Specifically, the Task Force did highlight the evidence that surgeons who reported injection of fat into
the subcutaneous plane and into the superficial to mid-muscular plane experienced 63% and 82% risk reductions respectively of pooled fatal and non-fatal PFEs.
In contrast, those reporting injections into the deep muscular plane experienced a 403% increase in the risk of pooled fatal and non-fatal PFEs.
Hence the Task Force concluded: “It has been suggested that gluteal vein injury allows an ingress of the injected fat across a pressure gradient. It is strongly recommended that practitioners performing this procedure avoid deep muscle injections. Though mid to superficial muscle and subcutaneous injections are safer, it is likely that some risk remains with them.
“It is further recommended that large bore single-hole cannulae larger than 4.1mm be used for grafting and that the cannula not be directed downward. It is possible that there may be protective value in keeping the injection cannula in motion while injecting to avoid a single large bolus injection into
“PFE should be considered in a patient experiencing significant hemodynamic or pulmonary instability during the intra- and post-operative period, and such patents should be immediately transferred to a hospital with critical care services.”
Patients interested in gluteal augmentation through fat grafting should be made aware of the risk of pulmonary fat embolism, techniques that can be employed to decrease known risks of mortality and complications with this procedure, and alternatives that include silicone implant-based gluteal augmentation. Further anatomical, clinical and post-mortem studies are needed to confirm findings of this limited study and to identify techniques that may improve the safety of gluteal fat grafting. AMP