In vivo validation of a miniaturized electrochemical oxygen sensor for measuring intestinal oxygen tension

• Published in: American journal of physiology: Gastrointestinal and liver physiology Vol. 317; no. 2; pp. G242 - G252
• Main Authors: Gray, Mark E, Marland, Jamie R K, Dunare, Camelia, Blair, Ewen O, Meehan, James, Tsiamis, Andreas, Kunkler, Ian H, Murray, Alan F, Argyle, David, Dyson, Alex, Singer, Mervyn, Potter, Mark A
• Format: Journal Article
• Language: English
• Published: United States American Physiological Society 01.08.2019
• Subjects: Anastomosis; Animal models; Animals; Blood flow; Dimensional Measurement Accuracy; Hypoxia; Intestines - blood supply; Ischemia; Ischemia - diagnosis; Ischemia - etiology; Materials Testing - methods; Medical equipment; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion - complications; Microtechnology; Monitoring, Physiologic - instrumentation; Monitoring, Physiologic - methods; Occlusion; Oxygen - analysis; Oxygen - chemistry; Oxygen - metabolism; Oxygen Consumption; Oxygen tension; Patients; Precision medicine; Rats; Reproducibility of Results; Sensors; Small intestine; Surface Tension; Therapeutic applications; superior mesenteric artery occlusion; hypoxemia; intestinal resection and anastomosis; miniaturized electrochemical oxygen sensor; intestinal serosal tissue oxygen tension
• ISSN: 0193-1857; 1522-1547
• DOI: 10.1152/ajpgi.00050.2019

Recent advances in the fields of electronics and microfabrication techniques have led to the development of implantable medical devices for use within the field of precision medicine. Monitoring visceral surface tissue O tension ( ) by means of an implantable sensor is potentially useful in many clinical situations, including the perioperative management of patients undergoing intestinal resection and anastomosis. This concept could provide a means by which treatment could be tailored to individual patients. This study describes the in vivo validation of a novel, miniaturized electrochemical O sensor to provide real-time data on intestinal . A single O sensor was placed onto the serosal surface of the small intestine of anesthetized rats that were exposed to ischemic (superior mesenteric artery occlusion) and hypoxemic (alterations in inspired fractional O concentrations) insults. Control experiments demonstrated that the sensors can function and remain stable in an in vivo environment. Intestinal decreased following superior mesenteric artery occlusion and with reductions in inspired O concentrations. These results were reversible after reinstating blood flow or by increasing inspired O concentrations. We have successfully developed an anesthetized rat intestinal ischemic and hypoxic model for validation of a miniaturized O sensor to provide real-time measurement of intestinal . Our results support further validation of the sensors in physiological conditions using a large animal model to provide evidence of their use in clinical applications where monitoring visceral surface tissue O tension is important. This is the first report of real-time continuous measurements of intestinal oxygen tension made using a microfabricated O sensor. Using a developed rodent model, we have validated this sensor's ability to accurately measure dynamic and reversible changes in intestinal oxygenation that occur through ischemic and hypoxemic insults. Continuous monitoring of local intestinal oxygenation could have value in the postoperative monitoring of patients having undergone intestinal surgery.