19364 is not your code, its for free flaps, big money!
The physician excises a free flap of skin, fat, and muscle from another site on the patient for use in the reconstruction of the breast following a modified radical or radical mastectomy. The free flap is excised with careful dissection of vascular channels, commonly from the thigh or buttocks, and the operative wound is sutured in a layered repair. In preparation for the graft, the mastectomy scar is excised with blood vessels preserved. The free flap is transferred to the mastectomy site and microvascular anastomosis is done to provide the graft with a viable blood supply. The physician adjusts the flap for the most aesthetic appearance and secures it with sutures to the chest wall, adjacent muscles, and skin. If the free flap does not have sufficient fat, a breast implant may be required. The chest incision is repaired with sutures
your code is 19301, normal repair is included unless he puts in a tissue expander of some sort.