Expiratory Flow Relief Control for High-Flow Respiratory Therapy
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Solution Overview
Problem
Existing respiratory therapy systems do not adequately adjust gas flow rates to match patient breath cycles, leading to discomfort and potential clinical inefficiencies during inspiration and expiration.
Innovation Solution
A respiratory system that adjusts gas flow rates based on detected breath cycles, using a controller to synchronize inspiration and expiration phases, with adjustable thresholds and a positive feedback system to maintain minimum and maximum flow rates, ensuring patient comfort and clinical efficacy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the flow rate is reduced during expiration to improve patient comfort, then patient comfort is improved, but the flow rate may fall below clinically relevant or safe thresholds
Solution Approach 1:
The system dynamically adjusts the flow rate based on the patient's breath cycle phase, transitioning from a static flow rate to a dynamic one that varies with inspiration and expiration. During expiration, the flow rate is reduced to improve comfort, while during inspiration, it is increased to meet respiratory demands. This dynamic adjustment resolves the contradiction by making the flow rate adaptive rather than fixed.
Solution Approach 2:
The system employs feedback control to monitor the flow rate and adjust it according to the detected breath cycle phase. The controller continuously monitors expiration phases and adjusts the flow rate accordingly, ensuring that comfort improvements during expiration do not compromise safety thresholds. The feedback mechanism allows real-time optimization of the flow rate based on actual patient respiratory patterns.
2Productivity
If the flow rate is increased during inspiration to meet respiratory demands, then respiratory support is improved, but the system complexity increases
Solution Approach 1:
The system uses the patient's own breath cycle to trigger flow rate adjustments, eliminating the need for external control inputs or complex algorithms. The breath cycle detector automatically identifies inspiration and expiration phases, and the controller autonomously adjusts the flow rate based on these detections. This self-service approach improves respiratory support effectiveness while minimizing system complexity by leveraging the patient's natural physiology for control.
Solution Approach 2:
The system employs pneumatic sensing through the flow sensor to detect breath cycle phases without requiring additional mechanical or electronic complexity. The flow sensor utilizes pneumatic principles to monitor gas flow characteristics and identify inspiration/expiration transitions, providing a simple yet effective method for triggering flow rate adjustments without adding significant system complexity.
3Ease of operation
If expiratory flow relief is applied to improve comfort, then patient comfort is improved, but the flow rate variation amplitude must be precisely controlled
Solution Approach 1:
The system changes the flow rate parameter dynamically based on the breath cycle phase, specifically reducing the flow rate during expiration to provide relief. The controller modulates the flow rate parameter within a defined range, adjusting its amplitude to balance comfort improvement with control precision. This parameter change approach allows expiratory flow relief to be implemented while maintaining manageable control requirements through predefined adjustment ranges.
Data Source
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AI summary
Systems and methods for conducting respiratory therapy in a respiratory system can adjust a flow of respiratory gases to a patient based upon a detected patient breath cycle. The respiratory system can include a non-sealed patient interface. The respiratory system can be configured to deliver a high flow therapy. The system can synchronize the flow rate with the detected breath cycle of the patient. The amplitude of the flow rate variation can be based partially on a value selected by the user. The adjustments to the flow rate can be done by controlling the motor speed using a positive feedback system. The adjustments to the flow rate can also be limited by the controller preventing the flow rate from crossing a minimum and/or maximum threshold.