Robert Fearn, MRCP, MSc, MBChB, Swathi Rajagopal, MBBS. Homerton University Hospital NHS Foundation Trust
Background: Colorectal surgery for benign and malignant conditions commonly results in the formation of an excretory stoma with population prevalence rates as high as 2-4 per thousand. Stoma patients are prone to a number of complications, which include acute kidney injury, hospital readmissions, skin complications and a reduced quality of life (Villafranca).
Methods: The ostom-i Alert Sensor is a medical device that uses a flexible sensor which attaches to a stoma bag and measures deformation of the bag whilst filling. It is able to relay volume data back to the patient and clinical team in real time via a Bluetooth connection to a smartphone or tablet. To validate the use of the system to detect volume changes, five devices in turn were attached 4 to a 300ml ostomy bag and were filled with set volumes (0ml; 100ml; 200ml; 300ml; 350ml). This process was repeated 5 times per device. The change in impedance (ohms) created by flexion of the detection strip was converted via an analogue digital converter to the nominal flex values given.
Results: 125 individual measurements were taken (5 runs of 5 volumes on each of 5 separate devices). Mean Flex (+-SD) at each of the five set volumes across the 5 devices tested is given. At 0ml filling Flex measured 1076 units (+-35.1). At 100ml Flex measured 928 units (+-30.2); at 200ml Flex measured 839 units (+-32.1 ); at 300ml it was 796 units (+-31.3) and at 350ml it was 800 units (+-31.3) . The proportional change in impedance for the incremental volumes measured (% change +-SD) was 0-100ml 13.69% (+-0.009); 100-200ml 9.66% (+-0.003); 200-300ml 5.09% (+-0.003) and 300-350ml -0.52% (+-0.002).
Discussion: A novel non-invasive wireless medical device that attaches to the outside of a stoma bag can accurately detect changes in volume up to, but not beyond the capacity of the bag. This can be used to provide real time stoma output data to patients and their clinical teams. Through a system of early warnings and prompted early intervention, this device is expected to reduce bag leakage events and guide fluid management with a view to reducing stoma-related complications.
Flexion values for a single ostom-i Alert Sensor
An ostom-i Alert Sensor in place on a stoma bag
Reference: Arenas Villafranca JJ, López-Rodríguez C, Abilés J, Rivera R, Gándara Adán N, Utrilla Navarro P. Protocol for the detection and nutritional management of high-output stomas. Nutr J. 2015;14:45.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 87654
Program Number: S056
Presentation Session: Instrumentation / Devices / Technologies Session
Presentation Type: Podium