Patient Interface Expiratory Filtration for Aerosol Containment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing respiratory support systems fail to effectively manage expiratory gases, which can transmit infectious aerosols and contaminants, particularly during high flow therapy, posing a risk to healthcare workers and patients.

Innovation Solution

A patient interface with an inspiratory element and an expiratory element featuring a gas permeable body that treats expiratory gases by intercepting and slowing aerosols and contaminants before they exit, using materials like polyester, polyurethane, or nylon, and physical structures such as filaments and pleats to create a tortuous path.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a patient interface is designed to fit tightly over the nose to deliver gas effectively, then gas delivery effectiveness is improved, but comfort deteriorates due to pressure on the nose and surrounding areas

Engineering Contradiction:
Improvegas delivery effectivenessVSAvoidpressure on nose and surrounding areas
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patient interface is divided into separate functional zones: a cushion portion that contacts the patient's face and a frame portion that structures the interface. The cushion is further segmented into a nasal portion with apertures and a forehead portion, allowing different regions to serve different purposes (gas delivery vs. sealing/comfort).

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The nasal portion of the cushion incorporates apertures that allow gas to pass through to the patient's nose, creating a localized gas delivery zone. The forehead portion provides a sealing surface without apertures. This local differentiation allows effective gas delivery to the nose while distributing pressure away from sensitive areas through the forehead contact.

Inventive Principle:
Principle #3Local quality

2Stability of the object's composition

If headgear is used to secure the patient interface, then stability and positioning are improved, but comfort deteriorates due to pressure on the head

Engineering Contradiction:
Improveinterface positioning stabilityVSAvoidpressure on head
Core Design Contradiction:
Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The headgear is segmented into a first headgear member and a second headgear member that can be independently adjusted. This segmentation allows each strap to be tuned separately to distribute pressure more evenly across the head while maintaining secure positioning of the interface.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The headgear incorporates adjustable mechanisms that allow dynamic modification of strap tension and positioning. This enables the interface to be securely held in place while allowing the user to adjust the distribution of pressure to minimize discomfort on the head.

Inventive Principle:
Principle #15Dynamics

3Ease of manufacture

If the patient interface design is simplified for ease of manufacture, then manufacturing cost decreases, but cleaning accessibility deteriorates

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidcleaning accessibility
Core Design Contradiction:
Ease of manufactureVSEase of operation

Solution Approach 1:

The patient interface is designed as separable components (cushion, frame, headgear) that can be manufactured using standard processes and then assembled. The cushion with its apertured nasal portion and non-apertured forehead portion can be manufactured as a single piece using molding techniques, maintaining manufacturing simplicity while enabling effective cleaning access to all surfaces including the aperture edges.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP4208239B1Patient interface for delivery of gas
Publication Date: 2026.05.20 FISHER & PAYKEL HEALTHCARE LTD
  • EP4208239B1 patent drawingFigure 1
  • EP4208239B1 patent drawingFigure 2~4
  • EP4208239B1 patent drawingFigure 5~7

AI summary

A patient interface for delivery of gas to a patient comprises at least one inspiratory element for directing a flow of gas to a patient airway, at least one expiratory element comprising an expiratory gas flow path for directing expiratory gases from the patient; and at least one gas permeable body in the expiratory gas flow path. Each inspiratory element comprises at least one inspiratory lumen through which said flow of gas is directed. The gas permeable body is configured such that expiratory gases in the expiratory gas flow path are directed through the gas permeable body before exiting the patient interface.