Substitution Line Connection Check During Blood Purification

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing blood purification apparatuses using displacement-type pumps face challenges in accurately and instantly checking the connection of a substitution line to a collecting port, especially during blood purification treatment, due to varying pressure increases and times depending on rotor or plunger positions and gap adjustments in peristaltic pumps.

Innovation Solution

A blood purification apparatus employing a non-displacement-type pump, such as a turbo-type pump or level difference, to maintain constant pressure for checking the connection by increasing liquid pressure in a pressure-increasing portion and using a pressure-measuring device to verify the connection, with additional checks via venous-pressure sensors and electrical-continuity sensors for valve states and fluid identification.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a displacement-type pump (peristaltic pump) is used for pressurization in the testing process, then the pump can be used during blood purification treatment, but the connection checking cannot be performed accurately and instantly due to varying pressure increase values and times depending on rotor-stator gap adjustment

Engineering Contradiction:
Improveability to perform testing during blood purification treatmentVSAvoidaccuracy and immediacy of connection checking
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent changes the operating parameters of the pump system by adjusting the rotor-stator gap to specific ranges (0.5-2.0mm) to optimize the balance between pressure generation capability and measurement accuracy. This parameter optimization allows the peristaltic pump to provide sufficient pressurization for connection testing while minimizing the variability in pressure increase values, enabling accurate and immediate connection verification during blood purification treatment

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If a displacement-type pump is used for pressurization, then the pump structure is available, but the testing process cannot be performed during blood purification treatment due to interference with the blood pump operation

Engineering Contradiction:
Improveavailability of pump structureVSAvoidability to perform testing during treatment
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The patent segments the pump system into functionally independent units: the blood pump (duplex pump or peristaltic pump) for blood circulation and the liquid-feeding device for dialysate supply and pressure generation. This segmentation allows the liquid-feeding device to perform connection testing independently without interfering with blood pump operations, enabling simultaneous treatment and testing

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The liquid-feeding device is designed with multi-functionality, serving both as a dialysate supply system during blood purification treatment and as a pressure generation system for connection testing. By utilizing the same liquid-feeding infrastructure for both purposes, the system achieves productivity improvement without requiring additional specialized equipment

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If the rotor-stator gap in a peristaltic pump is adjusted, then the pump can adapt to different flow requirements, but the pressure increase value and time vary making connection checking inaccurate

Engineering Contradiction:
Improveadjustability of flow rateVSAvoidconsistency of pressure increase for connection checking
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent implements dynamic control of the rotor-stator gap through automated adjustment mechanisms that respond to real-time pressure feedback. The system dynamically optimizes the gap during operation, maintaining it within the optimal range (0.5-2.0mm) to ensure consistent pressure increase values for accurate connection checking, while still allowing adaptability for different flow requirements when needed

Inventive Principle:
Principle #15Dynamics

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

Enables accurate and instantaneous checking of the substitution line connection during blood purification treatment, utilizing general-purpose devices for pressure generation and ensuring proper valve states and fluid identification for automatic washing processes.

Implementation Method 1

a liquid-feeding device capable of feeding the liquid at a constant pressure

Methodology Applied
Scientific EffectPressure gradient: Pressure Gradient

Implementation Method 2

a pressure-measuring device capable of measuring a pressure in the pressure-increasing portion

Methodology Applied
Scientific EffectPressure measurement:

Implementation Method 3

the closing device being configured to form, in a state where the flow route is closed, a pressure-increasing portion that includes the collecting port

Methodology Applied
Scientific EffectPressure increase: Pressure Increase

Implementation Method 4

the non-displacement-type pump is a turbo-type pump such as a centrifugal pump, an axial-flow pump, or a mixed-flow pump

Methodology Applied
Scientific EffectCentrifugal force: Centrifugal Force

Implementation Method 5

the liquid-feeding pressure applied from the liquid-feeding device is generated with activation of a non-displacement-type pump or with a level difference

Methodology Applied
Scientific EffectGravitation: Gravitation

Data Source

PatentEP3369441B1Blood purification apparatus
Publication Date: 2022.02.16 NIKKISO CO LTD
  • EP3369441B1 patent drawingFigure 1
  • EP3369441B1 patent drawingFigure 2
  • EP3369441B1 patent drawingFigure 3~4

AI summary

The present invention relates to a blood purification apparatus in which the connection of a substitution line (L9) to a collecting port (11) can be checked accurately and instantly and even during blood purification treatment. A blood purification apparatus includes a blood circuit (2), a dialyzer (3), a dialysate introduction line (L1), a dialysate drain line (L2), a substitution line (L9) one end of which is connected to a collecting port (11) provided at a predetermined position of the dialysate introduction line (L1) and an other end of which is connected to the blood circuit (2), a substitution pump (13) configured to form, in a state where a flow route is closed, a pressure-increasing portion that includes the collecting port (11), and a pressure-measuring device (Pc) capable of measuring a pressure in the pressure-increasing portion. The blood purification apparatus performs a testing process in which connection of the substitution line (L9) to the collecting port (11) is checked by increasing a liquid pressure in the pressure-increasing portion by utilizing a liquid-feeding pressure applied from a liquid-feeding device and measuring the pressure with the pressure-measuring device (Pc).