Concept to reality – time to change the catheter

Professor Marcus Drake

12 March 2019

A Foley catheter is the most common type of indwelling urinary catheter, which are used when a patient is unable to urinate for themselves. Despite having been developed nearly 90 years ago, 100 million people worldwide are reliant on them. But the Foley catheter, as would perhaps be expected in a design from the 1930s, has a variety of problems resulting in infection, blockage, pain and distress for patients.

Professor Marcus Drake of the University of Bristol has used the MRC Confidence in Concept scheme from the Elizabeth Blackwell Institute to progress a modern replacement for the Foley catheter called the Flume catheter which improves upon the old design, and to develop it to the proof of concept stage.

The Foley catheter is essentially a thin tube made of silicone or latex with a slightly hardened tip to allow easy insertion. Once inserted, it is held in place with a saline-inflated balloon inside the bladder. Drainage holes above this allow urine to escape. However, the placement of the drainage holes above the balloon mean that some of the urine collects and cannot drain, providing an excellent substrate for catheter-associated urinary tract infections, which can lead to salt encrustation on the catheter and drainage holes. The placement of the holes below the hardened tip also rendered them prone to blockage and can also be extremely uncomfortable for the patient.

The new Flume catheter aims to address these limitations by placing the draining hole within the balloon and placing a soft balloon over the hard tip. It also incorporates a host of other improvements which will enhance the preexisting design both for the clinician and the patient.

Indeed, laboratory results that Professor Drake have obtained thanks to the grant confirm that the Flume catheter results in much better drainage and resistance against infection when compared with Foley catheters.

The Flume Catheter Company was set up to bring the new device to market and is currently making close to 300 devices required for approval for human trials; funding for these has also been established in Bristol and Southampton, and the company hopes to be able to release the new design in 2020.

Professor Drake credits the Elizabeth Blackwell Institute’s MRC Confidence in Concept program with enabling him and his team to develop the Flume catheter thus far:

“The grant from Elizabeth Blackwell Institute has been instrumental in allowing us to develop an idea into a well-defined prototype, with supporting laboratory data. Proof of concept testing is essential to allow ideas to be developed, and the money received for this study has been essential to get this idea off the ground.

“We were awarded £150k grant from National Institute for Health Research (NIHR) Research for Patient Benefit scheme in September 2018 for first in human testing to take this novel design forward something that would not have been possible without the Confidence in Concept funding from Elizabeth Blackwell Institute.”