Pulse oximetric assessment of anatomical vascular contribution to tissue perfusion in the gastric conduit

Background: Tubularized stomach is a common substitute used after oesophageal resection. The risk for gastric conduit ischemia, as well as the mechanisms and dynamics for the occurrence of deficient tissue perfusion during the critical construction of a gastric tube, is poorly understood. Methods: Twenty-nine patients that underwent oesophagectomy were studied with transmural pulse oximetry of different parts of the stomach, and at predefined preparatory steps during the construction of the gastric conduit. Results: After ligation of the left gastric artery (LGA), a reduction to 83.5% in tissue saturation was observed. Three patients (10.3%) had a sustained saturation despite ligation at this point. During final preparation of the gastric tube, and after stapling of the minor curvature, saturation fell to 76.5%. Saturation increased significantly to 80.0% 2 h after the stapling, just before construction of the anastomosis (P = 0.021). There was no association between the level of oxygen saturation and the risk of anastomotic dehiscence. Conclusion: During gastric tube construction for oesophageal replacement, conduit perfusion, measured as oxygen saturation with pulse oximetry, decreases significantly. The main cause of this reduction seems to be ligation of the LGA and the final stapling of the gastric tube. Future studies are needed to establish the clinical implications of this finding.