Title: Development of a multi-parameter oesophageal sensor for the early detection of Multiple Organ Dysfunction Syndrome (MODS).
Funder: Department of Health (England)

Abstract: The project will comprise of three Phases. Phase I will involve the design and development of the Multi-parameter oesophageal sensor, associated instrumentation and software algorithms This work will be accomplished by building on previous research by the investigators in this area. User and Service User involvement will be sought to highlight design issues and considerations. A brief on the technical specifics of each sensor are: The P O2 sensor will consist of a ruthenium luminophore immobilised in a silicone rubber polymer at the tip of an optical fibre. After pulsatile excitation from a blue light source transmitted by the optical fibre, ruthenium luminescence will be detected by a photodetector. The half-life of the fluorescent pulses is inversely proportional to the oxygen tension in the tip. The P CO2 sensor will consist of a dye in a bicarbonate buffer fixed at the end of the fibre and covered by a hydrophobic membrane permeable to CO2. The presence of CO2 will change the colour of the dye, which can be detected by passing light into the dye at the fibre tip and measuring the absorbance. The SpO2 sensor will consist of red and infrared emitters and a photodetector placed on a small printed circuit board. The reflected light from the tissue will be captured by the photodetector and the ratio of red/infrared light absorption converted to SpO2. The three sensors will be integrated into a single sensor suitable for oesophageal placement. At all stages throughout the development, biocompatible materials will be chosen, so as to conform to safety standards. An instrumentation unit, based on an existing technology platform will be produced and optimised to drive the optical sensor and to facilitate good quality measurements. Software to record the optical signals acquired from the tissue will be developed. The light signals from the P O2, P CO2 and SpO2 sensors will be incorporated into algorithms to provide quantitative measurements of tissue oxygenation. The multi-parameter sensor will be evaluated in-vitro using tissue phantoms whereby the performance characteristics of the sensor evaluated. In Phase II Research Ethics and MHRA applications will be made. Service User involvement will be requested in aiding the design of the clinical investigations. The research ethics application will request permission to perform measurements in 30 surgical patients and 60 post-surgical ICU patients. The aim of the first clinical investigation on patients undergoing surgery is to evaluate the functionality of the multi-parameter sensor and allow for the calibration and modification of algorithms The sensor will be inserted into the lower oesophagus, with the total measurement period not exceeding two hours. Measured variables will be compared simultaneously with arterial blood gas analysis. For the ICU investigation, the sensor will be inserted into the lower oesophagus in patients deemed at risk of post-surgery complications. The patients will be monitored continuously for 24 hours following surgery and measured variables will be compared against standard clinical monitoring data and outcome. In Phase III the acquired data will be analysed and trends in the measured data will be correlated with clinical monitoring data and observations. All results will be disseminated at peer review journals, national and international conferences and at a Service User discussion group. During the Service User group discussion, other possible avenues for dissemination will be discussed. Throughout all phases of the project the corresponding technology transfer offices of both City University and Barts Health NHS Trust will engage in detailed market research analysis, securement of all IP, economic evaluation of the developed technology and actions to encourage commercial interest in the project.


Research activity codes: 4.2 EVALUATION OF MARKERS AND TECHNOLOGIES
Health categories: INFLAMMATORY AND IMMUNE SYSTEM;INFECTION