Non-revascularized epigastric free flap: no all-or-none survival pattern

We have previously shown that the epigastric flap in Dark Agouty rats, measuring approximately 6 x 4 cm with borders related to well-defined anatomical structures, does not exhibit an all-or-none survival pattern. This study was designed to investigate the survival pattern of non-revascularized epigastric flaps in three other rat strains (Sprague-Dawley, Brown-Norway, and Lewis). In concordance with our earlier observations, but in contrast to reports by many other groups, in none of the used strains was an all-or-none survival pattern observed. Survival varying from 2 to 30% (mean, 12%) of the original flap, without significant differences between the strains, was found. The locations of survival exhibited a clear pattern, probably owing to the fat pad in the subcutis and revascularisation from the recipient wound edges.