Flexible Bag Spacer for MDI Lung Deposition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current inhalation devices, including metered-dose inhalers (MDIs) and spacer devices, are inefficient in delivering medication to the lungs, with most particles impacting the throat and only a small percentage reaching the airways due to issues with particle size, flow rate, and breathing pattern coordination, leading to drug wastage and poor treatment outcomes.
Innovation Solution
A spacer device with a demountable, flexible bag that forms a chamber with the body, allowing for the formation of a cloud or mist of medication, which can be inhaled without the need for coordination, featuring a valveless design to reduce static electricity and improve flow, and adjustable size for user comfort and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a metered-dose inhaler is used directly into the mouth, then the device structure is simple, but most particles impact the throat and only about 12% reach the airways
Solution Approach 1:
The patent introduces a spacer device as an intermediary component between the MDI and the patient's mouth. This spacer includes a holding chamber that receives the aerosolized medication and a mouthpiece for inhalation, allowing particles to settle and be delivered more effectively to the airways rather than impacting the throat directly.
Solution Approach 2:
The spacer device is divided into separate functional components: a holding chamber for medication reception, a mouthpiece for inhalation, and a body structure that guides airflow. This segmentation allows each component to optimize its specific function and improves overall medication delivery efficiency.
2Productivity
If a spacer device is used to improve medication delivery, then lung deposition increases, but particles still adhere to chamber walls due to static electricity and impaction
Solution Approach 1:
The patent applies an antistatic treatment to the interior surfaces of the holding chamber and mouthpiece. This parameter change reduces static electricity buildup, thereby minimizing particle adhesion to walls and improving the amount of medication that reaches the patient's airways.
Solution Approach 2:
The antistatic treatment is applied locally to the interior surfaces that contact the aerosolized medication and airflow. This localized application ensures that particle adhesion is reduced precisely where particles interact with the device surfaces, while other components maintain their structural integrity.
3Ease of operation
If breath-activated inhalers are used to avoid coordination requirements, then ease of operation improves, but most particles still impact the back of the throat
Solution Approach 1:
The spacer device acts as an intermediary that decouples the inhalation action from the actuation timing. The holding chamber receives the aerosol cloud and allows the patient to inhale at their own pace without needing to coordinate with the actuation moment, while the mouthpiece design guides particles toward the airways rather than the throat.
4Productivity
If conventional spacer devices are used, then medication delivery improves, but a significant percentage of particles are lost to the atmosphere during exhalation
Solution Approach 1:
The spacer device is designed to allow continuous rebreathing of the medication cloud. During exhalation, unabsorbed particles are not simply vented but are recirculated back through the holding chamber and mouthpiece, providing multiple opportunities for the patient to inhale and absorb the medication, thereby reducing wastage.
Solution Approach 2:
The holding chamber serves as an intermediary reservoir that captures and retains medication particles during exhalation, preventing them from being lost to the atmosphere. The chamber allows the medication to be rebreathed through the mouthpiece, extending the useful action of the delivered dose.
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 spacer device significantly increases the percentage of medication reaching the lungs, reduces drug wastage, and provides improved comfort and ease of use by allowing uncoordinated breathing, with experimental results showing a 59% increase in lung deposition and minimal retention in the device.
Implementation Method 1
the flexible bag serves as reservoir to allow for the formation of a cloud or mist of the drug to be inhaled
Implementation Method 2
the flexible bag being configured to be at least partially inflatable and at least partially deflatable commensurate with breathing and/or rebreathing
Data Source
AI summary
The invention relates to a valveless spacer device for a metered dose inhaler (MDI), the spacer device comprising a body having an inlet and an outlet opposed from the inlet, a demountable, flexible bag attached to the body, the bag and body together defining a chamber, such that the inlet and outlet are in fluid flow communication with an interior of the chamber, wherein the inlet is configured to be connected to an MDI containing a drug to be inhaled and wherein the flexible bag, following actuation of the MDI, serves as a reservoir allowing for the formation of a cloud or mist of the drug therewithin which is then ready for inhalation, the flexible bag being configured to be at least partially deflatable and at least partially inflatable commensurate with a single breath and/or rebreathing.