Is injecting fat under the muscle safe with a BBL?

Hello and Great Question.  I appreciate the time you are spending researching this procedure.  My name is Dr. Matthew J. Nykiel.  I am a Board Certified Plastic Surgeon, a Fellowship Trained Cosmetic Surgeon, and a Butt Augmentation Specialist.
The recommendation for a BBL is to place the fat above the muscle because injecting it into the muscle puts you at higher risk of this complication.  I would have a discussion about this risk with your plastic surgeon and confirm where he/she likes to inject the fat.  
I hope that helps!  Best of Luck!
Matthew J. Nykiel, MD
#CoreAesthetic
Butt Augmentation Specialist
Liposuction Specialist
Board Certified Plastic Surgeon

Thanks for your question. Injecting fat under the muscle or into the muscle is dangerous as it can cause pulmonary fat enbolism. With Brazilian butt lift we transfer fat from one area of the body to the other.  These fat cells are transferred in microinjections throughout multiple planes in the buttock tissue so that they can gain new blood supply and live in their new home, providing increased volume and shape to the buttocks.  

Fat embolus is a very serious and known complication of fat transfer (which has been recently spotlighted in the media). While it is true, injection of donor fat into the infra-muscular plane (within the muscle) increases fat viability, this does come with a significant increase in risk. There are large vessels deep to and within the muscle which can be inadvertently injected while grafting leading to a fat embolus. The consequences of such a complication are very serious and life threatening.
BBL/gluteal lipoaugmentation demonstrates a dramatically higher risk profile than other surgeries. The Aesthetic Surgery and Educational and Research Fund has convened a task force as well. The hope is that we will have more concrete guidelines for addressing these very serious complications.
That being said, the safest way to avoid fat emboli is to stay in the subcutaneous plane (at the expense of fat viability) and avoid the deeper muscular plane. If grafting of the deep plane is planned, surgeons should consider blunt cannulas and aspiration prior to injection. Using a supra-gluteal approach to minimize the risk of inadvertent intravascular injection has also been proposed. While this will likely impact graft viability negatively, it will also lower the risk of a serious complication.
According to AAASF data the risk of death from BBL will range from 1:3000 (subcutaneous grafting should reduce this risk relative to intramuscular grafting). By comparison the risk of fatal complication from abdominoplasty is 1:13,000. It is unclear how the relative risk falls with subcutaneous injection vs. intramuscular injection (however, in all likelihood, it is less).
No result is worth risking one's life for. I find that the patients who focus not on the volumization but rather the contouring benefits of the liposuction are happier than those whose sole goal is size. Relatively speaking, the subcutaneous plane is the "safe" plane.
With regards to your specific question, I would discuss your concerns with your surgeon. This will him/her to alleviate your concerns.
In summary, the procedure can be safely performed, however, they should be performed by a board certified (ABPS) plastic surgeon with experience. These risks should be discussed as well as the strategies being employed to avoid them.

The answer to your question is YES and NO.  Should you consider cancelling the procedure, in my opinion, Yes.  Is it routine to inject fat under or in the muscle, No.BBLs have become a plastic surgery fad which apparently has a potentially high complication rate that can lead to serious consequences, including death.  This fad, while attractive, is in my opinion not worth the potential consequences.  To that end, I have stopped doing BBLs in my personal plastic surgery practice after having done several hundred successful BBLs.I highly recommend you discuss this very popular but controversial surgery with your personal plastic surgeon, and then make your own decision.

The take-home point of recent research is that traditional methods of transfer of fat into the gluteal muscles should be abandoned in favor of fat transfer though large cannula to areas directly visible beneath the skin.  Ask your PS if “under the skin” fat transfer is performed with blunt large diameter cannulae with transfer only the tissue directly under the skin

A Brazilian Butt Lift (BBL) has become one of the most dangerous cosmetic procedures because of fat embolism.  The recommendation is to place the fat above the muscle because injecting it into the muscle puts you at higher risk of this complication.  I would have a discussion about this risk with your plastic surgeon and confirm where he/she likes to inject the fat.  

There has been some preliminary indications that BBL is associated with higher risk of Pulmonary Embolism. This is mostly due to use of small canula for injection. there is a preliminary recommendation not to inject the fat under or into the muscle. I have been doing this procedure for 12 years and fortunately have never had a patient who had PE! 

Hi. Not at all, as you already said fat is never to be injected under the muscle, and I really do not believe your PS do so, for he knows how high is the risk for developing thromboembolism which  is a life risk condition.You may see some of my cases below, in none of them fat was injected under the muscle.International Member of the American Society of Plastic Surgeons (ASPS)
Member of the International Society of Aesthetic Plastic Surgery (ISAPS)
25 years experience

It is not safe.  Fat placed under the muscle or in the muscle has been seen in every autopsy performed on patients who had a BBL and died of pulmonary fat embolism.  There has never been an autopsy of a patient who died of pulmonary fat embolism where there was only fat in the subcutaneous plane.  It is now advised to NOT place fat in the muscle (or beneath it) by the major plastic surgery societies around the world.  Please see the attached reference to the research which serves as the basis for this advisory. 

 There's been a lot written in the plastic surgery journals about risks of fat embolism's being higher when fat is injected into the muscle during a BBL.  Some claim the probability of this complication being one and 3000 which would make it one of the most dangerous cosmetic procedures.  There have been numerous cases of patients who have had autopsies after dying where operative reports state fat was not injected into the muscle but fat is found in the muscle during the autopsy. The truth is the thickness of the fat layer above the muscle is a relatively thin in the gluteal region and it's difficult to not have any fat go into the muscle.  This is a blind procedure and unless someone is using an ultrasound it's difficult to know for certain if the cannula tip is vault is in the muscle or above it. obviously if you're injecting deep then you will be in the muscle and if you're injecting just below the skin you will be in the fat or sub dermal layer.  The risk factors that have been stated to increase the risk for this complication are injecting deep into the muscle layer, using thin or a small cannula's. I personally believe that the proper use of adequate tumecent solution letting this numbing solution with the vasoconstrictive drug, epinephrine be injected at least 15 minutes before the fat transfer  is also an adjuvant to keeping the procedure safer.  I do inject fat into the muscle layers and have since I first did this procedure in 1999.  I perform approximately 400 liposuction cases per year and 25 percent of these  include fat transfer such as a BBL or breast enhancement. Each plastic surgeon chooses their own technique. My guess is probably more than half the plastic surgeons and up injecting at least some fat into the muscle layer during the procedure whether they are aware of it or not as was pointed out in the autopsy studies. Fat embolism's are generally fairly rare and our unique specifically to BBL's in regards to presenting a more significant risk. The American Society of plastic surgeons has asked its members to have honest discussions about these risks which each patient prior to signing up for the procedure. More research is needed to help improve the safety of this procedure. I personally am interested in developing the use of ultrasound of technology to help identify the gluteal vans during the procedure allowing fat to be injected in the muscle while still staying away from the veins that are known to be the target of the complication. Please talk to your plastic surgeon about his or her approach.  Of course nobody wants to take risks but some risks are unfortunately unavoidable.  The question becomes what is a reasonable risk for the benefit of having the procedure. Best, Mats Hagstrom M.D.