Combined assessment of intestinal viability using laser doppler flowmetry and laser fluorescence spectroscopy

Introduction. The development of an objective non-invasive method for intraoperative assessment of intestinal viability remains urgent for modern surgery. In this context, the method of laser fluorescence spectroscopy (LFS) of coenzymes of oxidative metabolism, as well as a combination of this technique with the simultaneous use of laser Doppler flowmetry (LDF) seems promising. Materials and methods. The model of ischemia-reperfusion of the small intestine of 4 Californian Rabbits was used to study the relationship of the parameters of LFS and LDF with the histological picture. A model of intraoperative ischemia was used by temporarily clamping the trunk of the cranial mesenteric vascular bundle for 90 min, followed by intraoperative and postoperative reperfusion for 60 minutes and 24 hours, respectively. LDF and LFS data were recorded from intestine at the end of the intraoperative reperfusion period. 24 hours after the surgery, the animals were subjected to histologic evaluation of intestine ischemic changes, which were compared with the LDF and LFS data. Diagnostic value of LDF and LFS, and their combination for intraoperative assessment of intestinal viability were analyzed. Results. A significant correlation was found between the parameters of LDF, LFS and the degree of ischemic changes according to the histological data. The method of isolated assessment of the difference in the fluorescence of reduced nicotin adenine dinucleotide (NADH) before and after ischemia-reperfusion (77.3 %) has the greatest diagnostic value. The method has the highest sensitivity with a combination of differences in LDF and LFS values before and after ischemia-reperfusion (85.7 %) (P<0.05). Conclusions. LFS, as well as its combination with LDF, is a useful method for objective assessment of intestinal viability, which requires further research and has potential for clinical use.