Dialysate pH-Buffer Control for Sorbent Hemodialysis Loops

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing hemodialysis systems struggle to accurately manage dialysate pH and bicarbonate concentration due to unpredictable changes caused by sorbent materials, necessitating a need for systems and methods that can control these parameters while minimizing system size and fluid requirements.

Innovation Solution

A dialysate flow loop system with a urea sensor and infusate system to add bicarbonate buffer, controlled by a controller to achieve predetermined bicarbonate concentration, and a pH-buffer management system to adjust pH using acid or base equivalents, with optional pH and urea sensors for feedback control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If sorbent materials are used to remove urea from dialysate, then urea removal capability is improved, but pH and bicarbonate concentration become unpredictable

Engineering Contradiction:

Improveurea removal capabilityVSAvoidpH and bicarbonate concentration predictability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system employs pH sensors and bicarbonate sensors to continuously monitor dialysate pH and bicarbonate concentration. The controller receives sensor signals and dynamically adjusts acid concentrate and base concentrate flow rates to maintain target pH and bicarbonate levels, creating a closed-loop feedback control system that compensates for sorbent-induced variations

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system dynamically changes operational parameters (acid concentrate flow rate, base concentrate flow rate) based on real-time sensor readings. The controller modifies these parameters to counteract the unpredictable pH and bicarbonate changes caused by sorbent materials, transforming a static system into a dynamically adjustable one

Inventive Principle:

Principle #35Parameter changes

2Device complexity

If traditional pH control methods are used, then system simplicity is maintained, but precise pH and bicarbonate management cannot be achieved

Engineering Contradiction:

Improvesystem simplicityVSAvoidpH and bicarbonate concentration control precision

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The system incorporates pH sensors and bicarbonate sensors that provide real-time feedback to the controller. This feedback mechanism enables precise adjustment of acid and base concentrate flow rates, achieving accurate pH and bicarbonate control without requiring overly complex manual intervention systems

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system performs self-adjustment through automated controller logic that processes sensor inputs and modifies concentrate flow rates without operator intervention. This self-service capability maintains operational simplicity while achieving precise chemical parameter control

Inventive Principle:

Principle #25Self-service

3Quantity of substance

If regenerative hemodialysis systems are used, then fluid volume requirements are reduced, but pH prediction becomes difficult

Engineering Contradiction:

Improvedialysate fluid volumeVSAvoidpH change predictability

Core Design Contradiction:

Quantity of substanceVSDifficulty of detecting and measuring

Solution Approach 1:

The system uses real-time pH sensing feedback to monitor and adjust dialysate chemistry as it circulates through the regenerative system. This allows the compact regenerative design to maintain predictable pH control despite the reduced fluid volume and intensified sorbent interactions

Inventive Principle:

Principle #23Feedback

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 effectively maintains predetermined bicarbonate and pH levels in dialysate, ensuring precise patient treatment by dynamically adjusting based on urea content and pH readings, thus improving treatment efficacy.

Implementation Method 1

a urea sensor that measures or allows for the calculation of urea content of the dialysate

Methodology Applied

Scientific EffectUrea detection:

Implementation Method 2

an infusate system wherein the infusate system can be configured to add a bicarbonate buffer component to the dialysate

Methodology Applied

Scientific EffectBuffering:

Implementation Method 3

add unbuffered sodium bicarbonate

Methodology Applied

Scientific EffectDissolution: Solvation

Implementation Method 4

a pH-buffer management system to adjust pH using acid or base equivalents

Methodology Applied

Scientific EffectpH adjustment:

Implementation Method 5

acid or base equivalents are added to the dialysate during operation

Methodology Applied

Scientific EffectAcid-base reaction:

Implementation Method 6

a dialysate flow loop for circulating a dialysate through a dialyzer

Methodology Applied

Scientific EffectDiffusion: Diffusion

Implementation Method 7

circulating a dialysate through a dialyzer

Methodology Applied

Scientific EffectFiltration: Filter (physical)

Data Source

PatentUS12491298B2pH and buffer management system for hemodialysis systems

Publication Date: 2025.12.09 MOZARC MEDICAL US LLC

AI summary

Systems and methods for managing the pH of a dialysate fluid during hemodialysis therapy. The systems and methods adjust dialysate pH and buffer concentration to generate a predetermined total bicarbonate buffer concentration in a dialysate entering a dialyzer.