Dialysis Priming Sensor Waveform Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dialysis priming sensors are inaccurate due to sensitivity to ambient light, tube properties, and fluid type, leading to errors in detecting when a dialysis fluid reaches the correct position within a dialysis tube.
Innovation Solution
A dialysis priming sensor system using at least two light emitters and a light detector, activated in a sweeping pattern, samples light output data to create waveforms that are compared to reference curves to accurately determine if a tube is present and filled with fluid, regardless of ambient light or fluid properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a light sensor is used to detect when cleansing fluid has reached the end of a tube, then the priming detection function is enabled, but the accuracy deteriorates due to sensitivity to ambient light, tube properties, and fluid type
Solution Approach 1:
The patent divides the detection system into multiple light emitters (at least two) and light detectors positioned at different locations around the tube. Each emitter-detector pair provides independent measurement channels, and the processor combines data from multiple channels to determine fluid presence. This segmentation allows the system to cross-validate signals and filter out ambient light interference, thereby improving both reliability and precision simultaneously.
2Measurement precision
If a single light emitter and detector are used, then the device complexity is low, but the detection accuracy deteriorates due to inability to differentiate transmissive and reflective light patterns
Solution Approach 1:
The patent positions light emitters and detectors at specific locations around the tube with particular orientations. The first emitter is positioned to detect transmissive light patterns when fluid is present, while the second emitter detects reflective light patterns from the tube wall. Each emitter-detector pair has optimized local geometry for its specific detection purpose, enabling accurate differentiation between dry and wet tube states without requiring overly complex structures.
Solution Approach 2:
The processor activates light emitters in a sequential sweeping pattern rather than simultaneously, creating periodic detection cycles. During each sweep period, the processor samples detector output multiple times (between 10-100 samples, preferably 50-75) to build waveform data. This periodic activation with multiple sampling points allows the system to create distinctive waveform patterns for different tube states, improving detection precision while keeping the hardware relatively simple.
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 provides reliable detection of fluid presence in dialysis tubes, reducing errors and ensuring proper priming of dialysis machines, thereby enhancing the accuracy and reliability of dialysis treatments.
Implementation Method 1
The detector is configured to detect light emitted by the first emitter, the second emitter, and the third emitter that interacts with or passes through the patient tube
Implementation Method 2
The example system, apparatus, and method, in an embodiment, perform a sweeping pattern with light emitters for performing an analysis based on transmissive and reflective light caused by the light interacting with the tube and any fluids in the tube
Data Source
AI summary
A priming sensor for a medical fluid delivery device is disclosed. In an example, the priming sensor includes light emitters and a detector. The detector is configured to detect light emitted by the emitters that interacts with a patient tube connected to the priming sensor. A processor of a medical fluid delivery device causes the emitters to operate in a sweep pattern during a sweep period. The processor receives output data from the detector that is indicative of light detected during the sweep period. The processor creates an output waveform corresponding to the sweep period based on the output data and compares the output waveform to at least one reference waveform to determine one of (a) a no-tube state, (b) a dry tube state, or (c) a wet tube state. The processor provides an output indicative of the comparison for operation of the medical fluid delivery device.