Various surgical delay methods and compare with ischemic preconditioning in the rat tram flap

The transverse rectus abdominis myocutaneous (TRAM) pedicled flap is applied most frequently for breast reconstruction. This flap's major drawback is necrosis of the skin paddle. We used a variety of flap delay techniques and ischemic preconditioning to increase the surviving area of the TRAM flap in rat and the resuslts are compared in between. We used 6x3 cm sized TRAM flap in 40 Wistar rats. One control group, 3 delay groups and ischemic preconditioning group were established (n=8 in each group). Group 1: Control group TRAM flap was eleveted from non-dominant pedicle and flap was sutured to the original bed. Group 2: Delay group 1, left superior deep epigastric vessels were cut. One week later TRAM flap was elevated. Group 3: Delay group 2, only skin incision of the skin paddle was done. One week later TRAM flap was elevated. Group 4: Delay group 3, only scin incision was done and left superior deep epigastric vessels were cut. Group 5: Ischemic preconditioning group, TRAM flap was elevated. Ischemic preconditioning was performed by 3 cycles of 10 minutes of repeated ischemia/reperfusion periods and flap was sutured to the original bed. Flap viability was assessed 1 week after the surgical procedure, surviving flap area was recorded as a percentage to the whole flap area and microangiographi was applied two rat each group. Group 2, group 4, group 5 demonstrated a significantly lower area of flap necrosis than the control group. We determined IO is increase the surviving area of the TRAM flap but not effective method as many as surgical delay technique.