Novel oxygen saturation imaging endoscopy to assess anastomotic integrity in a porcine ischemia model

BACKGROUND: Establishing anastomotic integrity is crucial for avoiding anastomotic complications in colorectal surgery. This study aimed to evaluate the safety and feasibility of assessing anastomotic integrity using novel oxygen saturation imaging endoscopy in a porcine ischemia model. METHODS: In three pigs, a new endoscope system was used to check the mechanical completeness of the anastomosis and capture the tissue oxygen saturation (StO(2)) images. This technology can derive the StO(2) images from the differences in the absorption coefficient in the visible light region between oxy- and deoxy-hemoglobin. Bowel perfusion at the proximal rectum was assessed before and after the anastomosis, and 1 min and 30 min after the ligation of the cranial rectal artery (CRA). RESULTS: The completeness of the anastomoses was confirmed by the absence of air leakage. Intraluminal oxygen saturation imaging was successfully performed in all animals. There was no significant difference in the StO(2) level before and after the anastomosis (52.6 ± 2.0 vs. 52.0 ± 2.6; p = 0.76, respectively). The StO(2) level of the intestine on the oral side of the anastomosis one minute after the CRA ligation was significantly lower than immediately after the anastomosis (15.9 ± 6.0 vs. 52.0 ± 2.6; p = 0.006, respectively). There was no significant difference in the StO(2) level between 1 min after and 30 min after the CRA ligation (15.9 ± 6.0 vs. 12.1 ± 5.3; p = 0.41, respectively). CONCLUSION: Novel oxygen saturation imaging endoscopy was safe and feasible to assess the anastomotic integrity in the experimental model.