Switchable Voltage Measurement Circuit for Dialysate Conductivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hemodialysis systems lack efficient methods to monitor and maintain constant sodium concentrations in dialysate solutions, which is crucial for patient comfort and health, as existing methods require direct contact with the patient's body and are cumbersome due to calibration requirements.
Innovation Solution
A device with a data collecting cell and circuit that measures conductivity of dialysate solutions using a switchable voltage measurement unit, allowing for quick and accurate conductivity measurements without direct patient contact or pre-calibration, utilizing a cell constant pre-determined by electrode geometry and material, and operating at a frequency of about 100 kHz.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If direct contact methods are used to monitor sodium concentrations in dialysate, then measurement capability is achieved, but patient comfort deteriorates and operational complexity increases
Solution Approach 1:
The patent uses conductivity as an intermediary parameter to indirectly measure sodium concentration in dialysate. Instead of directly contacting or measuring sodium ions, the system measures the electrical conductivity of the dialysate solution, which correlates with sodium concentration. This intermediary approach allows accurate monitoring without direct patient contact or complex calibration procedures.
2Measurement precision
If calibration procedures are implemented to ensure measurement accuracy, then measurement precision improves, but device complexity and time requirements increase
Solution Approach 1:
The system performs self-calibration by automatically determining the cell constant through measurement of known conductivities of standard solutions. The microprocessor-controlled system autonomously calculates calibration factors without requiring manual intervention or complex external calibration equipment, thereby reducing calibration time and simplifying the overall process while maintaining measurement accuracy.
3Measurement precision
If switchable voltage measurement units are used to measure both input and output voltage, then measurement capability improves, but device complexity increases
Solution Approach 1:
The patent employs a single switchable voltage measurement unit that can measure both the input voltage to the conductivity cell and the output voltage from the cell. This multi-functional component eliminates the need for separate measurement devices, thereby reducing overall device complexity while maintaining the capability to accurately measure both voltages for conductivity calculation.
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 quick, accurate, and self-calibrating conductivity measurements of dialysate solutions, reducing discomfort risks by monitoring sodium levels without direct patient contact and eliminating the need for real-time calibration, thus improving patient treatment parameters.
Implementation Method 1
a circuit for measuring the conductivity of a medical fluid includes a data collecting cell through which a medical fluid is configured to flow, an input voltage source that provides set input voltage to the data collecting cell, a voltage measurement unit configured to measure the input voltage and an output voltage of the data collecting cell
Data Source
AI summary
A circuit for measuring the conductivity of a medical fluid, the circuit comprising: a data collecting cell through which a medical fluid is configured to flow; an input voltage source that provides an input voltage to the data collecting cell; a voltage measurement unit configured to measure the input voltage and an output voltage of the data collecting cell; and a switch in communication with the voltage measurement unit, the switch configured to switch between a first state in which the voltage measurement unit is configured to measure the input voltage and a second state in which the voltage measurement unit is configured to measure the output voltage of the data collecting cell.