Liquid Ventilation System with Extraction Valve
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional liquid ventilation systems face challenges such as over-pressurization of the lungs during chest compressions, contamination risks due to open configurations, and limited extraction rates by mechanical pumps.
Innovation Solution
A closed-loop liquid ventilation system with a reservoir for perfluorochemical fluid, a suction pump to reduce pressure, and an extraction valve to control fluid communication, along with a sensor to measure intra-lung pressure and an injector for precise PFC administration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If chest compressions are applied to pump the heart during cardiac arrest, then blood circulation is maintained, but the lungs become over-pressurized and damaged when filled with incompressible PFC fluid
Solution Approach 1:
The system dynamically adjusts the PFC fluid delivery rate based on the compression cycle phase. During compression phases when lung volume decreases, the controller reduces or pauses PFC delivery to prevent over-pressurization. During relaxation phases when lung volume increases, the controller resumes PFC delivery. This dynamic coordination allows chest compressions to maintain circulation while preventing lung damage.
Solution Approach 2:
The system uses sensors to detect lung volume or pressure changes in real-time and feeds this information back to the controller. The controller uses this feedback to adjust the PFC delivery rate accordingly, ensuring that PFC is not delivered when the lungs are being compressed and would be over-pressurized. This closed-loop control resolves the contradiction between maintaining circulation and preventing lung damage.
2Quantity of substance
If a bolus of PFC is force-infused into the lungs, then the lungs receive adequate oxygen supply, but the cyclic force of the thumper piston prevents PFC from exiting fast enough causing over-pressurization
Solution Approach 1:
Instead of continuous force-infusion, the system uses periodic delivery of PFC fluid synchronized with the compression cycle. PFC is delivered during relaxation phases when lung volume increases and pressure decreases, and delivery is paused during compression phases. This periodic action allows PFC to enter and exit the lungs at controlled rates, preventing over-pressurization while maintaining adequate oxygenation.
Solution Approach 2:
The PFC delivery rate is dynamically adjusted based on the real-time compression cycle phase and lung volume. The controller modulates the delivery rate to match the changing capacity of the lungs, delivering more PFC when lung volume is high and less or none when lung volume is low. This dynamic control prevents pressure buildup while ensuring adequate PFC quantity for oxygenation.
3Productivity
If mechanical pumps are used to extract PFC fluid from the lungs, then PFC removal is achieved, but the extraction rate is limited by pump performance characteristics
Solution Approach 1:
The system replaces the mechanical pump extraction mechanism with a pressure-driven flow system. By coordinating PFC delivery with the compression cycle and using the natural pressure differentials created during compression and relaxation phases, the system enables PFC to flow in and out of the lungs without requiring high-speed mechanical extraction pumps. This substitution reduces device complexity while maintaining adequate extraction rates.
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 effectively cools the patient without risking lung damage from over-pressurization, maintains a sterile environment by being closed, and achieves efficient PFC extraction and administration.
Implementation Method 1
a suction pump connected to the reservoir to reduce pressure within the reservoir
Implementation Method 2
PFCs can be chilled significantly, and when applied to the body in a chilled state, they rapidly decrease body temperature
Data Source
AI summary
A liquid ventilation system includes a reservoir holding a perfluorochemical (“PFC”) fluid, and a suction pump connected to the reservoir to reduce pressure within the reservoir. A sensor is configured to measure an intra-lung pressure. An appliance is configured to be disposed within a patient. The appliance carries an injector to supply the PFC fluid through the appliance. An extraction valve is disposed on an extraction line between the appliance and the reservoir. The extraction valve is arrangeable between a first position enabling fluid communication from the appliance to the reservoir and a second position disabling fluid communication from the appliance to the reservoir.