Ventilator Trigger Synchronization Using Bioelectric Signals

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing ventilators face challenges in synchronizing breathing support with a patient's own efforts, particularly in children, due to leakage issues and sensitivity problems with pneumatic triggers, leading to increased patient workload and inefficient ventilation.

Innovation Solution

A computer program product that uses bioelectric signals, such as the Edi signal, to determine the precise timing of patient inhalation and adjusts the ventilator's trigger conditions based on pressure and flow measurements to synchronize inspiration phases with the patient's breathing cycle, potentially delaying or refining the trigger to match the patient's natural breathing rhythm.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a pneumatic trigger condition based on pressure and/or flow is set, then the ventilator can provide breathing support in support mode, but it becomes difficult to synchronize the ventilation correctly with the patient's breathing efforts due to leakage

Engineering Contradiction:

Improvesynchronization accuracyVSAvoidtrigger level setting

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent replaces the purely pneumatic trigger system with a hybrid system that incorporates electrical impedance measurement. The control unit measures electrical impedance between the patient's lips and the ventilator circuit to detect inhalation start, complementing the existing pneumatic pressure/flow triggers. This substitution of mechanical sensing with electrical sensing overcomes the limitations of pneumatic triggers in detecting true inhalation onset, especially in cases of leakage.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces electrical impedance measurement as an intermediary parameter to detect the moment of inhalation start. The impedance change between the patient's lips and the ventilator circuit serves as a mediator that provides more accurate timing information for trigger initiation, bridging the gap between pneumatic trigger conditions and actual patient breathing efforts.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the trigger is too insensitive, then false triggering is reduced, but an entire breath may be skipped

Engineering Contradiction:

Improvebreath detection accuracyVSAvoidbreathing support efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent applies multiple trigger detection methods (pneumatic pressure, pneumatic flow, and electrical impedance) simultaneously, using a partial action approach where each method contributes to overall trigger accuracy. By requiring concordance among multiple parameters rather than relying on a single threshold, the system achieves both high reliability in detecting true breaths and high productivity in delivering timely support without skipping breaths.

Inventive Principle:

Principle #16Partial or excessive action

3Measurement precision

If the trigger is too sensitive, then breath detection is improved, but an inspiration may be triggered in the ventilator when the patient is not ready to inhale

Engineering Contradiction:

Improveinhalation detection precisionVSAvoidtrigger timing accuracy

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent implements feedback by continuously monitoring multiple parameters (pressure, flow, and electrical impedance) and adjusting trigger decisions based on the pattern and timing of changes across all parameters. The control unit analyzes the coherence of signals from different sensors to confirm true inhalation events, providing feedback that prevents false triggering while maintaining high detection precision for genuine patient breaths.

Inventive Principle:

Principle #23Feedback

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

This approach improves synchronization between the ventilator and patient, reducing the workload on the patient by ensuring that ventilator support is aligned with natural inhalation, thereby enhancing the effectiveness of breathing support in support mode.

Implementation Method 1

measuring an electrical impedance between lips of the patient and the ventilator circuit

Methodology Applied

Scientific EffectElectrical impedance measurement: Electrical Resistance

Data Source

PatentEP2231245B1A computer program product, a control unit for a ventilator, and a ventilator

Publication Date: 2014.10.29 MAQUET CRITICAL CARE

Figure 1~2
Figure 3
Figure 4

AI summary

To set trigger conditions correctly in pneumatic mode, a ventilator is controlled according to the following: - obtaining a measurement value of a bioelectric signal representative of the patient's own breathing function; - determining, based on the bioelectric signal, at least one point in time in which the patient starts inhalation, - obtaining a measurement value to be used for triggering an inspiration phase in the ventilator during said at least one point in time, - determining a trigger condition for the inspiration phase on the basis of the measurement value, - using the trigger condition to for initiating inspiration when ventilating the patient in support mode.