Impact of saline fluid cushion on thermal damage during the double-flap technique after proximal gastrectomy using porcine stomach

The double-flap technique is an anti-reflux valvuloplasty used for esophagogastrostomy after proximal gastrectomy. This technique involves creating two muscular flaps on the remnant stomach using an electrosurgical knife, requiring precise dissection between the muscular and submucosal layers. Inaccurate dissection may cause thermal damage to the muscular flaps and the submucosal layer. To address this issue, we developed the "Saline Fluid Cushion" (SFC) method, which induces submucosal swelling via saline injection, to facilitate safer and easier flap creation. This study evaluates the impact of the SFC method on thermal damage during flap creation using a porcine stomach model. Three surgeons participated in the study, creating flaps (1.25 × 3.5 cm) with SFC and without SFC on porcine stomachs by electrosurgical knife. The stomach samples were fixed, sectioned, and stained with hematoxylin and eosin. Thermal damage was measured using a microscope and image analysis software. The SFC group required more time for flap creation (median: 86 s vs. 48 s, p < 0.001). However, histological analysis revealed less thermal damage in the SFC group on both the flap side (median: 0.76 mm vs. 2.82 mm, p < 0.001) and the mucosal side (median: 0.7 mm vs. 3.79 mm, p < 0.001). The use of SFC during flap creation reduced electrosurgical knife-induced thermal damage on both the flap and mucosal sides in porcine stomach model.