Optimization of anastomotic technique and gastric conduit perfusion with hyperspectral imaging in an experimental model for minimally invasive esophagectomy

Objective To optimize anastomotic technique and gastric conduit perfusion with hyperspectral imaging (HSI) for total minimally invasive esophagectomy (MIE) with linear stapled anastomosis. Summary Background Data Esophagectomy is the mainstay of esophageal cancer treatment but anastomotic insufficiency related morbidity and mortality remain challenging for patient outcome. Methods A live porcine model (n=50) for MIE was used with gastric conduit formation and linear stapled side-to-side esophagogastrostomy. Four main experimental groups differed in stapling length (3 vs. 6 cm) and anastomotic position on the conduit (cranial vs. caudal). Tissue oxygenation around the anastomotic site was evaluated using HSI and was validated with histopathology. Results The tissue oxygenation (ΔStO2) after the anastomosis remained constant only for the short stapler in caudal position (−0.4± 4.4%, n.s.) while it dropped markedly in the other groups (short-cranial: -15.6± 11.5%, p=0.0002; long-cranial: -20.4± 7.6%, p=0.0126; long-caudal: -16.1± 9.4%, p<0.0001) Tissue samples from deoxygenated stomach as measured by HSI showed correspondent eosinophilic pre-necrotic changes in 35.7± 9.7% of the surface area. Conclusions Tissue oxygenation at the anastomotic site of the gastric conduit during MIE is influenced by stapling technique. Optimal oxygenation was achieved with a short stapler (3 cm) and sufficient distance of the anastomosis to the cranial end of the gastric conduit. HSI tissue deoxygenation corresponded to histopathologic necrotic tissue changes. These findings allow for optimization of gastric conduit perfusion and anastomotic technique in MIE. Level of Evidence Not applicable. Translational animal science. Original article. ### Competing Interest Statement The authors have declared no competing interest. * HSI : hyperspectral imaging i.v. : intravenous MIE : minimally invasive esophagectomy OE : open esophagectomy ROI : region of interest SD : standard deviation SEM : scanning electron microscopy StO2 : hyperspectral oxygenation index