Non-invasive Blood Pressure Monitoring via Dialysis Line Pressure Waveforms
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current non-invasive blood pressure monitoring methods during hemodialysis are unreliable, uncomfortable, and sensitive to patient movement, failing to provide continuous and accurate measurements, which is crucial for predicting intradialytic hypotension and improving patient outcomes.
Innovation Solution
A non-invasive blood pressure monitoring system using pressure sensors integrated with arterial and venous dialysis lines, a peristaltic roller pump, and a learning algorithm that applies Fourier transforms to estimate blood pressure by modeling the relationship between pump speed and pressure waveforms, accounting for changes in line diameters and sensor placement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional arm-cuff blood pressure measurements are used, then the measurement is non-invasive and comfortable for patients, but the measurement is intermittent and unreliable for predicting blood pressure-related events
Solution Approach 1:
The patent implements continuous blood pressure monitoring by processing dialysis line pressure data at every time step throughout the treatment, rather than taking intermittent measurements. The system continuously estimates blood pressure by comparing arterial and venous line pressure waveforms, enabling real-time detection of blood pressure changes and prediction of hypotension events throughout the entire dialysis session.
2Reliability
If arterial cannulation is used for continuous blood pressure measurement, then the measurement is continuous and accurate, but the procedure is invasive and inappropriate for hemodialysis patients
Solution Approach 1:
The patent uses the dialysis blood lines as an intermediary medium to obtain blood pressure information without directly accessing the patient's artery. By measuring pressure waveforms in the extracorporeal blood circuit and processing the difference between arterial and venous line pressures, the system derives continuous blood pressure estimates non-invasively, eliminating the need for arterial cannulation while maintaining measurement accuracy.
3Object-affected harmful factors
If air-filled occluding arm cuff is used for blood pressure monitoring, then the measurement is non-invasive, but the cuff disrupts normal blood flow and requires significant settling time before next measurement
Solution Approach 1:
The system continuously monitors blood pressure throughout the dialysis treatment by processing pressure data from the dialysis lines without interruption. There are no measurement cycles that require stopping or settling periods, as the system constantly compares arterial and venous pressure waveforms to estimate blood pressure, eliminating the settling time issue entirely.
4Ease of operation
If pulse transition time method using ECG and PPG signals is used, then the blood pressure estimation is non-invasive and continuous, but the method introduces inaccuracies due to physiological factors and heavy reliance on accurate ECG triggering
Solution Approach 1:
The patent extracts blood pressure information directly from the mechanical pressure waveforms in the dialysis blood lines, removing the need for separate ECG and PPG measurements. By analyzing the pressure difference between arterial and venous lines, the system obtains blood pressure estimates without relying on ECG triggering or photoplethysmography, thereby eliminating the associated inaccuracies.
5Reliability
If volume clamp method with inflatable finger cuff is used, then the blood pressure monitoring is continuous and non-invasive, but the method causes pain or discomfort at the fingertips and is unreliable in patients with reduced blood flow to digits
Solution Approach 1:
The patent uses the dialysis blood lines as an intermediary to obtain blood pressure information without applying pressure to the patient's body. By measuring pressure waveforms in the extracorporeal circuit, the system derives continuous blood pressure estimates without causing pain, discomfort, or interference with digital blood flow, making it suitable for dialysis patients.
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 continuous, accurate, and comfortable blood pressure monitoring, enabling early detection of hypotension and improving patient outcomes by predicting blood pressure fluctuations during dialysis, thus optimizing treatment parameters.
Implementation Method 1
a peristaltic roller pump, and a learning algorithm that applies Fourier transforms to estimate blood pressure
Implementation Method 2
pressure sensors integrated with arterial and venous dialysis lines
Implementation Method 3
a learning algorithm that applies Fourier transforms to estimate blood pressure by modeling the relationship between pump speed and pressure waveforms
Data Source
AI summary
An aspect of the present disclosure describes an apparatus for non-invasive blood pressure monitoring that includes a plurality of pressure sensors, a plurality of sensor interfaces coupling the plurality of pressure sensors to at least one blood flow line disposed exterior from a patient, a pump for artificially generating blood flow through the at least one blood flow line, and a processor configured to receive pressure sensor measurements from the plurality of pressure sensors and generate a patient blood pressure estimation from the combined pressure sensor measurements.