Nitric Oxide Delivery Flow Control for Gentle Ventilation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current nitric oxide delivery systems face challenges in accurately measuring low flow rates, leading to shutdowns and adverse patient conditions, particularly during gentle ventilation, which requires lower flows than conventional ventilation.

Innovation Solution

An apparatus with a control circuit, flow sensor, and CPU to maintain a minimum therapeutic gas flow, featuring clinical decision support software to adjust flow limits and provide alerts, ensuring safe delivery by monitoring and controlling gas flow rates.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If current flow sensors and injector modules are used to measure breathing gas flow rate, then measurement is possible at normal flow rates, but measurement becomes inaccurate or impossible at low flow rates

Engineering Contradiction:
Improvebreathing gas flow rate measurementVSAvoidapplicability to gentle ventilation
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent changes the measurement parameters by using thermal dispersion flow sensors that operate on different principles than conventional sensors. These sensors measure flow based on heat transfer characteristics rather than pressure differential or mechanical movement, enabling accurate measurement at very low flow rates (down to 0.1 L/min) while maintaining functionality at higher flows, thus resolving the contradiction between measurement precision and adaptability to gentle ventilation

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent replaces mechanical flow measurement systems with electronic/thermal measurement systems. Instead of using mechanical components that require minimum flow to operate, the invention uses electronic flow sensors with no moving parts that can detect flow through thermal properties, eliminating the minimum flow requirement and enabling use in gentle ventilation scenarios

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If nitric oxide delivery system shuts down due to insufficient flow, then system protection is achieved, but patient safety is compromised due to rebound hypertension and oxygen desaturation

Engineering Contradiction:
Improvesystem operation reliabilityVSAvoidadverse patient effects
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent implements preliminary action by providing advance warning to clinicians before system shutdown occurs. The system monitors flow rates continuously and alerts users when flow approaches critical levels, allowing clinicians to intervene before the nitric oxide delivery shuts down, thereby preventing rebound hypertension and oxygen desaturation while maintaining system protection

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements feedback mechanisms where the system continuously monitors breathing gas flow and provides real-time information to clinicians about flow status. This feedback loop allows the system to warn of impending shutdown conditions and enables continuous nitric oxide delivery by alerting clinicians to maintain adequate flow rates, thus eliminating the harmful effects of abrupt shutdown

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

The apparatus ensures stable nitric oxide delivery by maintaining minimum flows, preventing shutdowns and adverse events, and supporting gentle ventilation strategies.

Implementation Method 1

a flow sensor to detect the flow of breathing gas from the breathing gas delivery system

Methodology Applied
Scientific EffectFlow sensing:

Data Source

PatentEP4154930B1Apparatus to deliver therapeutic gas to a patient
Publication Date: 2026.04.22 MALLINCKRODT PHARMACEUTICALS IRELAND LTD
  • EP4154930B1 patent drawingFigure 1
  • EP4154930B1 patent drawingFigure 2
  • EP4154930B1 patent drawingFigure 3

AI summary

Described is method of monitoring the delivery of therapeutic gas. The method includes the steps of receiving to a gas delivery device a desired concentration of therapeutic gas, providing flows of breathing gas and of therapeutic gas comprising nitric oxide, and delivering a combined flow of the breathing gas and the therapeutic gas. A first flow rate sensor measures a flow rate of the breathing gas, and the method further includes obtaining a flow rate of the therapeutic gas, setting upper and lower limits of breathing gas flow rate at which a shutdown of the gas delivery device is triggered, providing an alert when the upper or lower limit is reached, and automatically adjusting the upper and lower limits to avert shutdown of the gas delivery device.