What are the chances of developing a fat embolus or PE? I am having a tummy tuck, BBL and lipo.

Mizcurvas,
Although the risk of a DVT/PE or Fat embolus is relatively rare, these complications are extremely important to discuss with your plastic surgeon.  In general, the risk of PE/DVT with an abominoplasty (tummy tuck) alone is about 0.5% (as outlined in a 2015 article in Plastic an Reconstructive Surgery Journal).  With the addition of liposuction that risk increases to 1.1%.  But that was for all patients, male/female, different BMI, different ages, etc.  
For someone like you, who is young, healthy, and presumably no previous history of DVT/PE; your risk is likely very small.  Your plastic surgeon can discuss with you certain traits that may increase your risk, which can be found in the Caprini score.  
In order to reduce the chances of DVT/PE; there are certain steps that should be taken including the use of pneumatic compression devices during surgery, early ambulation after surgery, and if you are at an increased risk, the use of pre-operative anticoagulation such as heparin/lovenox.  
I agree with many of the other physicians that you should be wary of flying on a plane for a long flight soon after surgery.  If you do plan on flying, i would suggest frequently getting out of your chair and ambulating.  

Mizcurvas.   Your age and lack of comorbidities decrease risk, however BBl and Tummytuck simultaneously increase those risks.  If expected fat transfer is modest, then it is a reasonable.  If extensive, consider staging the surgery.  Be sure to consult with a board certified plastic surgeon.  Good luck!

Dear Mizcurvas,while there is always a risk of PE or fat embolus, that risk for young, healthy individual is minimal. I would suggest you to discuss this with your plastic surgeon.Daniel Barrett, MD, MHA, MS 

Certified, American Board of Plastic Surgery  

Member, Am. Society of Plastic Surgery