Assessment of small intestinal viability: A bioimpedance approach

Abstract

This thesis describes how bioimpedance measurements can be used to assess the viability (live or die) of the small intestines, after a period without sufficient blood supply (ischemia). Using machine learning we were able to classify intestinal tissue injury and viability based on bioimpedance data, with accuracies similar to or better than what is reported by using the present clinical method. The thesis describes how electrical parameters measured on the small intestine change during ischemia and reperfusion and describes the creation of a reference model for intestinal viability in a pig model. It also discusses how machine learning can be a relevant tool for analysis of longitudinal bioimpedance data. As a part of the methodology, the thesis discusses intraluminal microdialysis for detection and monitoring of ischemia and reperfusion, and the use of histology to provide a reference for the viability limit. The thesis combines knowledge and research from the fields of physics and medicine, in order to investigate a solution to a medical problem.