Symmetrical Tip Acute Catheter Minimizing Hemodialysis Recirculation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hemodialysis catheters experience recirculation issues due to purified blood being withdrawn directly into the arterial lumen, increasing the time required for hemodialysis procedures.
Innovation Solution
A symmetrical tip acute catheter assembly with diametrically opposed side openings and a septum-defined lumen configuration, which minimizes recirculation by ensuring separate pathways for blood flow through the arterial and venous lumens, reducing the likelihood of thrombus formation and optimizing fluid communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If purified blood exits the venous lumen close to where the arterial lumen withdraws blood, then the catheter structure is simple, but recirculation occurs increasing procedure time
Solution Approach 1:
The catheter tip design positions the arterial and venous openings at different angular positions around the catheter circumference (e.g., 180 degrees apart) and at different axial distances from the distal tip. This spatial separation in multiple dimensions prevents recirculation by ensuring that blood withdrawn through the arterial opening does not directly re-enter through the venous opening, thereby reducing procedure time without excessive structural complexity.
2Speed
If the catheter tip is made more rigid for acute placement, then speed of placement is improved, but recirculation and thrombus formation risk increase
Solution Approach 1:
The catheter incorporates a symmetrical tip design with specific geometric features (contoured edges, laser-cut openings) at the distal end that optimize blood flow separation and reduce recirculation. The tip geometry is specifically engineered with openings positioned at precise angular and axial locations, while the rest of the catheter body maintains standard properties. This localized optimization at the critical tip region improves reliability for preventing recirculation while maintaining overall placement speed.
3Productivity
If openings are made larger to improve fluid flow, then fluid communication is enhanced, but thrombus formation likelihood increases
Solution Approach 1:
The catheter tip openings feature contoured, rounded edges rather than sharp angular boundaries. The opening geometry includes curved surfaces that promote smooth blood flow transition and reduce turbulence. This curvature design allows adequate opening size for sufficient fluid flow while minimizing blood stasis and reducing the likelihood of thrombus formation at the opening edges.
Data Source
AI summary
A medical catheter assembly includes a catheter tip coupled to a distal end of an elongate catheter member and is symmetric about a plane defined by a septum of the elongate catheter member. The catheter tip defines first and second lumens, and the catheter tip defines first and second openings in the distal portion of the catheter tip. Each opening of the catheter tip is defined by a respective side surface of the catheter tip. Each opening is in fluid communication with a respective one of the first and second lumens of the catheter tip and with a respective one of a pair of lumens defined by the elongate catheter member. The distance between upper and lower surfaces of the catheter tip decreases from a distal end of the proximal portion toward a closed distal end of the catheter tip.