Preoperative shock wave treatment enhances ischemic tissue survival, blood flow and angiogenesis in a rat skin flap model

IntroductionExtracorporeal shock wave treatment (ESWT) has recently been shown to enhance skin flap survival. However, the bio-mechanisms operating during preoperative ESWT remain unclear. The aim of our study was to investigate whether preoperative ESWT can improve blood flow in ischemic skin flaps and to elucidate its possible mechanisms.Methods14 male-rats were randomized into two groups and an oversized ventral random-pattern flap was raised. Experimental group received extracorporeal shock-wave treatment (ESWT) with an energy of 500 mJ/mm2 seven days prior to total flap elevation, while control group received no treatment prior to total flap elevation. Seven days postoperatively, surviving flap area, perfused flap area, microvessel density and VEGF concentration were measured.ResultsSurviving flap area (59.43 ± 14.72 % to 42.71 ± 10.75 %, p = 0.026), perfused flap area (62.00 ± 8.58 % to 45.14 ± 10.50 %, p = 0.007), microvessel density (18.13 ± 5.11 to 11.09 ± 1.12, p = 0.016) and VEGF to total protein ratio (0.2107 ± 0.0935 to 0.0123 ± 0.0069, p = 0.008) were significantly elevated in the ESWT group.ConclusionPreoperative ESWT can improve skin flap survival through enhanced topical blood perfusion and neovascularization via elevation of angio-active factors.