Venous "supercharging" rat augments survival of the delayed TRAM flap

Adequate delay of a pedicled transverse rectus abdominis musculocutaneous (TRAM) flap might not necessarily require interruption of the venous system. The retained ipsilateral deep vein of the dominant pedicle could then be used as a secondary outflow source for potential salvage of a congested flap. A venous "super-charged" rat TRAM flap model has been designed to evaluate the efficacy of this maneuver. Seventy-two female Sprague-Dawley rats (CD) were equally divided into two major groups, differing only in whether a delay by division of the dominant cranial epigastric artery had first been performed. An inferior-based TRAM flap (nondominant) was raised for each rat, with three subsets of 12 rats in each group, ie, with the cranial epigastric vein subsequently divided (group control), retained (supercharged), or retained but the inferior pedicle divided (venous flap). Both supercharged subsets had significantly augmented flap survival when compared with flaps in their group raised without the cranial epigastric vein, whether a delay maneuver had (96 +/- 6% vs 89 +/- 7%; P = 0.012) or not (80 +/- 8% vs 65 +/- 21 %; P = 0.034) been performed. Flaps with only a cranial epigastric vein pedicle totally necrosed, implying that the observed enhancement in flap viability was not the result of transformation into a venous flap, but perhaps as a crossover flap where an adjacent venosome was captured. Venous supercharging can be accomplished by inclusion of the ipsilateral dominant deep vein, and should be a consideration in the clinical planning of delay maneuvers and for treatment of the compromised TRAM flap.