Introduction: Clinicians often place patients in heated rooms following elective muscle flap transfers in order to improve flap perfusion by encouraging vasodilation of the feeding recipient vessels. In contrast, we hypothesized that exposure of elective flaps to heated room temperatures could result in an unnecessary hyperthermic ischemic insult if the flaps were to be compromised by venous outflow obstruction; conversely, exposure of elective flaps to hypothermia during the early perfusion period may provide protection from venous occlusion. Methods: The rat rectus femoris muscle flap (n=6 per group) was elevated on its major pedicle and exposed to various room temperatures (hypothermia [50°F], ambient temperature [72°F], or hyperthermia [82°F]). Following flap elevation and 1 hour of perfusion (mimicking a flap that is being monitored on the floor), complete venous occlusion of the muscle flap was accomplished by placing a micro clamp on the major pedicle venous outflow for 3 hours. Following 3 hours of venous occlusion, micro clamps were removed reproducing a salvage procedure and flaps were allowed to reperfuse at body temperature. Muscle necrosis (per NBT staining) and edema (per wet to dry muscle weight ratio) were assessed following 24 hours of body temperature reperfusion in both experimental groups (exposed to ischemia) and control groups (non-ischemic) that were exposed to the above variable temperature parameters. Results: Ischemic exposed muscles demonstrated decreased muscle damage in the hypothermic group (8.5 +/- 6.7 %; P< 0.001) compared to the ambient temperature group (76.2+/ 23.0 %), and the hyperthermic group (97.3 +/- 1.4%). In fact, ischemic exposed, hyperthermia muscles demonstrated a trend towards increased necrosis when compared to the ischemic exposed, ambient temperature muscles. Furthermore, ischemic exposed muscles demonstrated decreased muscle edema in the hypothermic group (3.06 +/- 0.14; P< 0.001) compared to the ambient temperature group (3.73 +/-0.13), and the hyperthermic group (3.84+/-0.29). No difference was noted in muscle viability nor edema amongst non-ischemic control muscles irrespective of temperature exposure. Conclusion: Hyperthermic exposure of elective flaps during reperfusion does not provide protection to muscle flaps in the event of venous compromise. In stead, these results suggest a beneficial role for exposure of elective flaps to regional hypothermia during the early perfusion period in order to provide protection from IR injury in the event of a venous occlusion insult. The prophylactic exposure of flaps to hypothermia is further supported by the lack of a harmful effect when flaps were not compromised by venous occlusion.