You are wise to be concerned about the safety of performing combination surgery. Generally speaking, I individualize the care of each patient; there are some 27-year-olds who I would not perform this combination of surgery for and there are some 57 -year-olds who I feel very comfortable proceeding with.
Much can be learned from a careful history and physical examination. In addition, preoperative “clearance" from your internist/family practitioner will be helpful.
Choose your plastic surgeon carefully; ask to see lots of examples of similar patients who he/she has helped. Make sure you are being taken care of in a fully credited surgery center or hospital and by a well experienced anesthesia provider.