Post-operative monitoring of intestinal motility, ischemia, and inflammation for early detection of anastomotic leaks

Postoperative anastomotic leak can be a catastrophic event and current diagnostic modalities fail to provide timely detection. This failure to rescue directly leads to increased mortality, morbidity and worse outcomes. A new medical device (xBar by Exero Medical) is a diagnostic device intended to continuously monitor local intestinal function following GI surgery. The objective of this multi-center pilot study was to evaluate if this device can reliably detect anastomotic leaks earlier than the current standard of care.

The device’s platform technology is based on an electrode array collecting information from the surgical site representing physiological processes such as local inflammation and ischemia. Data recorded is relayed to a cloud database where a machine learning algorithm continuously classifies the accumulating stream of data into several “Leak States”. Here, a set of electrodes were embedded in a standard surgical drain. The device collected data for a duration of 3 to 10 days, while the surgical drain was in use. Our primary endpoints were safety and performance analysis – sensitivity, specificity, and time to detect severe anastomotic leaks.

We included 50 patients undergoing elective anterior resection were included (N=44 cancer patients, N=4 Diverticulitis and N=2 Prolapse). The average age was 63.6±13.3 years and 38% males. The average anastomotic height was 9.1±5.3cm from the anal verge. The surgical technique used was laparoscopic (N=26), Robotic (N=16) or open (N=8). Grade C anastomotic leak was observed in 6.0% (N=3) of the patients. The hospitalization time for the patients without leaks was 7.7±5.3 versus 15.0±7.9 days in patients with severe leak. The device had a sensitivity of 100% and Specificity of 91.5% at POD 2 and 100% sensitivity and 100% specificity at POD3. Notably, the clinical team diagnosed the leak after 6, 16 and 5 days in the three severe leak cases (9.0±6.1 days on average), in contrast to the earlier detection using the device (2.3±0.6 days on average, and at least 2 days before the clinical team). No device related serious adverse events were observed during the study and the device did not alter the patient outcomes.

This study demonstrates clinical feasibility of the xBar system. Local electrophysiological parameters are highly sensitive to the physiological processes underlying anastomotic leaks enabling early post-op monitoring ahead of systemic clinical signs. The drain proved to be a reliable form factor for the technology. During this study the algorithm was adaptive and learning from ongoing data – in an upcoming pivotal trial the system will be tested with fixed settings to validate xBar’s performance with sufficient statistical power.