UC Case Nos. 2019-020 and 2020-105
SUMMARY
UCLA researchers in the Department of Radiology have developed a novel catheter design that incorporates large drainage holes and a secondary flushing tube to allow for enhanced clearage of viscous biological fluids. Additionally, they have designed a control unit that enables continuous operation for catheter maintenance.
BACKGROUND:
Most existing catheter systems consist of a plastic tube with twisted “pigtail” shape that collects biological fluids via large cavities in the coil and deposits them in a collection bag at the other end. The holes in the central tube, or lumen, often clog when the biological fluid is viscous or contains particulates. For this reason, it is required for nurses to “flush” the lumen with saline 1-3 times a day to dilute the waste to be excreted and also clear the collection cavities. Clearing the catheter can be done in two ways: incorporating a 3-way stopcock connecting the saline source, waste bag and catheter drain line so that saline can be introduced by a turn of the stopcock or by disconnecting the catheter bag and directly injecting saline. Both of these methods require physical manipulation of the device and can lead to reintroduction of waste to the body as flushing occurs in the same lumen that leads to the waste collection bag. Due to the labor intensity of this process, catheters are cleansed with saline 1-3 a day even though higher frequency would result in fewer catheter complications.
INNOVATION:
UCLA researchers have designed a two lumen catheter that combines the central waste removal tube with a secondary flush line. The central lumen design is augmented with extra-large holes for solid waste removal while the flush line is outfitted with small holes to allow for high pressure flushing. The flush lumen is evenly fitted with small holes facing both the internal cavity of the catheter and the surrounding biological tissue. This serves to dilute the biological fluid as it enters the catheter and also flush the lumen to the waste collection bag. Such design improvements will enhance clearing rates and reduce maintenance as physical manipulation of the device is no longer necessary. Additionally, waste is flushed towards the collection bag, eliminating reintroduction to the body.
As frequent clearing is crucial, a control unit for continuous catheter flushing has also been developed. While intended for the Advanced Drainage Catheter, the control unit can be applied to any catheter system. A pump can either continually or intermittently administer saline while pulling vacuum on the central lumen, forcing waste and excess saline out. The volume in and out is continuously monitored so that an imbalance will trigger an alarm. The feedback can be directly uploaded to an electronic patient chart or even a smartphone app. The ability to continuously refresh catheter tubing means enhanced patient experience and reduced time consumption for healthcare professionals.
POTENTIAL APPLICATIONS:
- Healthcare
- Medical devices
- Catheter manufacture
ADVANTAGES:
- Elimination of waste re-entry to body
- Reduced maintenance time for healthcare professionals
- Reduced instances of clogging
- Continuous flushing vs the standard 1-3 times a day