Rotationally Actuated Fixation Mechanism for Gastrostomy Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing percutaneously insertable gastrostomy and jejunal devices face issues with long-term fixation, profile maintenance, and stability, as Foley balloon catheters can leak, pigtail catheters require sutures that may loosen, and malecot tubes have a high profile that limits patient mobility.
Innovation Solution
A medical device featuring a tubular catheter with a coaxially disposed sheath that includes a fixation point and radially deformable arms or a bulge portion, allowing for rotation to extend or retract and maintain a low profile, ensuring secure fixation and easy visualization of the device's state within the patient.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a Foley balloon catheter is used for percutaneous feeding, then the catheter can be inserted and retained within the patient, but the balloon may leak or catastrophically fail causing the catheter to no longer be properly positioned
Solution Approach 1:
The patent removes the balloon component from the catheter design entirely, replacing it with a fixation mechanism that uses a malecot tube with radially extendable arms that can be secured against the gastric wall without requiring an inflatable balloon, thereby eliminating the reliability issues associated with balloon leakage or failure
Solution Approach 2:
The fixation mechanism uses a simple, non-inflatable malecot tube design that does not rely on reusable inflatable components, providing a permanent fixation solution that eliminates the need for balloon inflation/deflation cycles and associated failure modes
2Stability of the object's composition
If a pigtail catheter is used for retention, then the catheter can be positioned within the patient, but sutures may become loose or slip over time if the patient is active
Solution Approach 1:
The malecot tube is divided into multiple radially extendable arms that can be independently positioned and secured against the gastric wall, providing stable fixation without requiring external sutures that may become loose or slip
Solution Approach 2:
The arms of the malecot tube are designed to be dynamically extendable and retractable, allowing the fixation mechanism to adapt to patient movement and gastric wall position changes while maintaining stable fixation without sutures
3Reliability
If a malecot tube is used with extendable arms, then the catheter can be retained within the patient, but the internal member maintains a relatively high profile limiting patient activities
Solution Approach 1:
The malecot tube arms are designed to nest within the body of the tube when not in use, and only extend radially when needed for fixation, thereby maintaining a low profile during patient activities while providing reliable retention when fixed
Solution Approach 2:
The arms transition from a retracted low-profile state during patient mobility to an extended fixation state when retention is needed, dynamically adjusting the profile height to accommodate both patient activities and secure retention requirements
4Reliability
If sutures are used to secure the catheter, then the catheter can be retained within the patient, but it is difficult to determine when the pigtail is properly installed
Solution Approach 1:
The device incorporates visual indicators such as color-coded components or visible markers on the malecot tube and arms that change or become apparent when the device is properly installed and fixed, allowing easy verification of correct installation without requiring complex imaging or assessment
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 device provides secure, long-term percutaneous access to the GI tract with a low profile, allowing patients to maintain mobility and enabling easy verification of the device's position, thereby overcoming the limitations of previous technologies.
Implementation Method 1
Friction between the sheath and the catheter causes the arms to buckle radially outwardly away from the sheath as the sheath and the catheter are rotated with respect to each other.
Implementation Method 2
This longitudinal relative motion compresses the malecot tube, which buckles the malecot arms outwardly because the malecot arms provide the least resistance to compression.
Data Source
AI summary
The present invention provides a gastrostomy or jejunal device for extended insertion into an abdomen of a patient. The device includes a catheter and a coaxial sheath that surrounds the catheter. The sheath includes a plurality of curved or oblique slots through the sheath materials that form a plurality of arms. A rotatable actuation device is provided to twist the sheath along its longitudinal axis which places the arms in compression and causes them to buckle radially outward beyond the circumference of the remainder of the sheath when the actuation device is rotated with respect to the remainder of the device.