Intestinal ischaemia especially in the postoperative period is a complication that is dreaded by all general surgeons and poses a considerable rise in mortality and morbidity of patients, not to mention the burden it puts on the physician and on the healthcare system. Its diagnosis is always subjective relying mostly on the physicians’ awareness and clinical suspicion rather than on any quantitative method. This project explores a quantitative tool and adapts online rapid sampling microdialysis (from its use in monitoring brain tissue ischaemia) to monitor ischaemia in human bowel and bowel anastomosis. It describes its translation from the bench top model, to the pilot model, to the animal model, and finally its application in the clinical setting to monitor patients for bowel ischaemia. The online microdialysis analyzer used in monitoring brain tissue in Kings College Hospital was modified and converted for use in the setting to monitor bowel in the labs of the Bioengineering Department at Imperial College London, under collaboration with the Department of Bio Surgery and Surgical Technology. The system was designed and construction supervised by Dr. Martyn Boutelle; and work on the system to construct and optimize carried out by PhD student Emma Corcoles. The clinical collaborate of the project was supervised by Professor Ara Darzi and carried out by Mr. Samer Deeba with joint supervision by Professor George Hanna. The catheter, connections, and deployment was optimized at St. Mary’s Hospital, part of Imperial College NHS trust. This project did prove the efficacy of microdialysis in monitoring bowel ischaemia in the clinical setting, but needs further work and development in the design of the catheter and miniaturizing the analyzer to be more reliable and robust. Multicenter trials are needed to gain its wide acceptance in the clinical practice.EThOS - Electronic Theses Online ServiceGBUnited Kingdo