Portable Dialysis Pump with Varying Pressure Profile
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional dialysis systems require large amounts of filtered water for hemofiltration, which is costly and raises safety concerns about water purity, and they struggle with clogging and clotting of dialyzer filters, reducing their effectiveness in toxin removal.
Innovation Solution
A portable dialysis system that generates a varying pressure profile within the blood and dialysate circuits using a rotor pump with a diameter of no greater than 4 inches, creating rapid cycles of positive and negative pressure to enhance toxin clearance without the need for excessive water infusion, thereby improving dialyzer clearance and reducing filter clogging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional hemofiltration systems use large amounts of filtered water to create high convective force, then toxin clearance is improved, but water consumption increases and safety concerns about water purity arise
Solution Approach 1:
The patent applies periodic action by cycling the blood pressure between high and low states (or negative pressure) in rapid succession. This periodic pressure variation creates alternating convective and diffusive transport mechanisms across the membrane, achieving effective toxin clearance without requiring continuous large volumes of water for ultrafiltration. The pump system switches between different pressure states to maintain treatment effectiveness while minimizing water consumption.
2Productivity
If higher trans-membrane pressure gradient is applied to improve filtration effectiveness, then toxin removal is enhanced, but filter clogging and clotting increases
Solution Approach 1:
The system uses periodic pressure cycling where the blood pressure is alternated between high and low states (or negative pressure) at frequencies greater than 0.5 Hz. This rapid cycling prevents sustained high pressure that would cause filter clogging, while still achieving effective toxin removal through the alternating convective and diffusive mechanisms. The periodic variation keeps the filter pores clear by preventing protein accumulation.
Solution Approach 2:
The patent applies inversion by using negative pressure states in the blood circuit, which is opposite to conventional positive pressure ultrafiltration. During negative pressure phases, fluid and solutes are drawn back into the blood, preventing filter clogging while maintaining effective toxin clearance. This bidirectional pressure approach reverses the conventional unidirectional ultrafiltration mechanism.
3Volume of moving object
If dialysis systems are made smaller and more portable, then device size is reduced, but dialyzer filters clog more quickly reducing treatment duration
Solution Approach 1:
The patent applies periodic pressure cycling at frequencies greater than 0.5 Hz to prevent filter clogging in compact dialyzers. This rapid pressure variation maintains filter patency by preventing protein and cell accumulation in the hollow fibers, thereby extending treatment duration despite the smaller filter size. The periodic mechanism compensates for the reduced surface area and increased susceptibility to clogging in compact designs.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system achieves enhanced clearance of middle to larger sized toxins using less than 10 liters of water, maintaining positive average pressure for extended periods, and prevents filter clogging, thus improving the efficiency and effectiveness of dialysis without additional components or water sources.
Implementation Method 1
a pump for pumping a fluid through the at least one tube segment and at least one of the plurality of blood and dialysate circuits; and operating the pump to apply a force to the at least one tube segment to generate fluid flow through the at least one tube segment with a pressure profile that varies between a positive pressure and a negative pressure
Implementation Method 2
Ultrafiltration occurs when water (along with small solutes) is driven from the blood to dialysate in the dialyzer because of the hydrostatic pressure gradient between the blood and dialysate compartments
Implementation Method 3
Hemofiltration achieves a higher removal of larger, poorly diffusible solutes through convective transport
Implementation Method 4
Diffusion removes toxins using a concentration gradient across the semi-permeable membrane
Data Source
AI summary
The present specification describes a modular, portable hemofiltration system, for providing improved clearance levels of blood toxins, which includes at least one roller pump that is designed and operated to generate a rapidly varying pressure profile of fluid within at least a blood circuit of the hemofiltration system.