<qa>  What is liposomal bupivacaine?The objective of this project is to evaluate the role of liposomal bupivacaine in postoperative pain control following tissue expander and implant based breast reconstruction. This unique formulation of bupivacaine lends this drug a longer duration of action and reduced plasma bupivacaine concentrations compared to plain bupivacaine. This agent has been demonstrated to be safe, well tolerated, and effective in a number of different clinical applications. However, its role has yet to be evaluated in the context of breast reconstruction. 