SMP Foam Hydrogel Composite for Hemorrhage Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hemorrhage management systems, such as compression, hemostatic gauze, and expandable foams, are inadequate as they do not effectively reduce the risk of infection, are limited in applicability, and have high rebleed rates and potential for systemic procoagulant exposure.
Innovation Solution
A composite hemorrhage management system comprising a shape memory polymer (SMP) foam and a Poly(ethylene glycol) Diacrylate (PEG-DA) N-vinylpyrrolidone (NVP) hydrogel (HG) that swells to absorb wound exudate, conforms to complex wound geometries, and provides antibacterial properties through iodine doping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional hemorrhage control systems (compression, hemostatic gauze, expandable foams) are used, then hemorrhage can be controlled to some extent, but they do not effectively reduce the risk of infection and have high rebleed rates
Solution Approach 1:
The patent uses a composite material consisting of a shape memory polymer foam matrix combined with hemostatic and antibacterial agents. This composite structure allows the device to simultaneously provide mechanical compression for hemorrhage control and chemical antibacterial action to prevent infection, resolving the contradiction between hemorrhage control effectiveness and infection risk reduction.
Solution Approach 2:
The shape memory polymer foam undergoes a phase transition from a compressed low-volume state to an expanded high-volume state when exposed to body temperature or specific chemical triggers. This parameter change enables the device to adapt its mechanical properties to provide sustained compression and filling pressure, improving hemorrhage control reliability while the incorporated antibacterial agents continuously reduce infection risk throughout the deployment period.
2Reliability
If conventional hemorrhage control systems are used, then bleeding can be managed, but they are limited in applicability to certain wound types and locations
Solution Approach 1:
The shape memory polymer foam device is designed to be universally applicable across different wound types, locations, and severities. The foam's ability to expand to various sizes and conform to different geometries, combined with its dual functionality of mechanical compression and chemical antibacterial action, makes it suitable for treating hemorrhages in diverse scenarios including traumatic wounds, surgical sites, and infected lesions, thereby improving adaptability while maintaining reliable hemorrhage control.
3Reliability
If hemostatic gauze with procoagulants is used, then hemostasis can be achieved, but there is potential for systemic procoagulant exposure and thermal tissue damage
Solution Approach 1:
The antibacterial and hemostatic agents are incorporated locally within the shape memory polymer foam matrix, ensuring that the active ingredients remain confined to the wound site. The foam structure acts as a reservoir that releases agents locally without systemic absorption, thereby achieving reliable hemostasis and infection prevention while eliminating the harmful effect of systemic procoagulant exposure. The local delivery mechanism is maintained through the physical containment within the foam matrix and controlled degradation or dissolution rates.
4Force
If expandable foams are used to treat hemorrhage, then pressure can be applied to the wound, but they are difficult to remove from the wound and have limited efficacy data
Solution Approach 1:
The shape memory polymer foam device exhibits dynamic properties that allow it to be easily removed from the wound site. The foam can be compressed to a low-volume state for insertion and then expands to provide necessary pressure, but its shape memory characteristics enable controlled contraction and removal without leaving residue or causing tissue damage. This dynamic behavior resolves the contradiction by maintaining adequate pressure application during use while enabling easy and clean removal afterward, unlike traditional expandable foams that are difficult to extract.
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 SMP foam/HG composite effectively stops severe arterial/venous bleeding within 2 minutes, absorbs wound exudate, reduces the risk of infection, and provides adequate force to prevent device dislocation, while maintaining biocompatibility and mechanical integrity.
Implementation Method 1
a shape memory polymer (SMP) foam, including open cells, having first and second states
Implementation Method 2
when the SMP foam is plasticized at 37° C. depressing a glass transition temperature (Tg) of the SMP foam to below 25° C.
Implementation Method 3
a hydrogel (HG) included within the cells... the composite is configured to be expanded to the second state within the wound when the SMP foam is plasticized
Implementation Method 4
swells to absorb wound exudate
Implementation Method 5
provides antibacterial properties through iodine doping
Implementation Method 6
The SMP foam/HG composite effectively stops severe arterial/venous bleeding within 2 minutes, absorbs wound exudate, reduces the risk of infection
Data Source
AI summary
An embodiment includes a wound dressing comprising: a shape memory polymer (SMP) foam, including open cells, having first and second states; and a hydrogel (HG) included within the cells; wherein (a) in a first position a composite, including the SMP foam and the HG, is configured to be located proximate a hemorrhagic tissue with the SMP foam in the first state; (b) in a second position the composite is configured to be expanded to the second state against the hemorrhagic tissue when the SMP foam is plasticized at 37° C. depressing a glass transition temperature (Tg) of the SMP foam to below 25° C. Other embodiments are described herein.