Quantitative Assessment of Blood Flow in the Gastric Conduit With Thermal Imaging for Esophageal Reconstruction.

OBJECTIVE: The study's primary aim was to evaluate the effectiveness of thermal imaging (TI) and its secondary aim was to compare TI and indocyanine green (ICG) fluorescence angiography, with respect to the evaluation of the viability of the gastric conduit. SUMMARY BACKGROUND DATA: The optimal method for evaluating perfusion in the gastric conduit for esophageal reconstruction has not been established. METHODS: We reviewed the prospectively collected data of 263 patients who had undergone esophagectomy with gastric conduit reconstruction. TI was used in all patients. ICG fluorescence was concomitantly used in 24 patients to aid comparison with TI. A cut-off value of the anastomotic viability index (AVI) was calculated using the receiver operating characteristic curve in TI. RESULTS: Anastomotic leak was significantly less common in patients with AVI > 0.61 compared with those with AVI ≤ 0.61 (2% vs 28%, P< 0.001). Microvascular augmentation was performed in 20 patients with a low AVI score and/or preoperative chemoradiotherapy. Overall ability was comparable between TI and ICG fluorescence regarding the qualitative evaluation of the gastric conduit. However, TI was superior in the quantitative assessment of viability. CONCLUSIONS: TI could delineate the area of good perfusion in the gastric conduit for esophageal reconstruction, which can help identify patients at high risk of anastomotic leak.

Initial Assessment of Mucosal Capture and Leak Pressure After Gastrointestinal Stapling in a Porcine Model.

BACKGROUND: Anastomotic leak is a leading cause of morbidity and mortality in gastrointestinal surgery. The serosal aspect of staple lines is commonly observed for integrity, but the mucosal surface and state of mucosa after firing is less often inspected. We sought to assess the degree of mucosal capture when using stapling devices and determine whether incomplete capture influences staple line integrity. METHODS: Porcine ileum was transected in vivo and staple lines were collected and rated for degree of mucosal capture on a 5-point scale from 1 (mucosa mainly captured on both sides) to 5 (majority of mucosa not captured). Mucosal capture was also assessed in ex vivo staple lines, and fluid leakage pressure and location of first leak was assessed. Stapling devices studied were Echelon Flex GST with 60-mm blue (GST60B) and green (GST60G) cartridges, and Medtronic EndoGIA Universal with Tri-Staple Technology™ with 60 mm medium (EGIA60AMT) reloads (purple). RESULTS: GST60B and GST60G staple lines produced significantly better mucosal capture scores than the EGIA60AMT staple lines (p < 0.001, in all tests). Compared to EGIA60AMT, leak pressures were 39% higher for GST60B (p < 0.001) and 23% higher for GST60G (p = 0.022). Initial staple line leak site was associated with incomplete mucosal capture 78% of the time. CONCLUSIONS: There are differences in degree of mucosal capture between commercial staplers, and the devices that produce better mucosal capture had significantly higher leak pressures. Further research is needed to determine the significance of these findings on staple line healing throughout the postoperative period.