End Effector Insulative Stop Members for Tissue Sealing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electrosurgical instruments often fail to provide uniformly reproducible pressure and controlled gap distance between electrodes, leading to ineffective or non-uniform tissue sealing, especially for larger vessels or thick tissues.

Innovation Solution

The development of a bipolar forceps with an end effector assembly featuring a pair of opposing jaw members that include insulative stop members to maintain a precise gap distance between electrically conductive surfaces, ranging from 0.001 inches to 0.010 inches, ensuring consistent tissue sealing by controlling pressure and electrical energy application.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If stop members are sprayed atop tissue engaging surfaces to maintain gap distance, then gap distance control is improved, but manufacturing precision deteriorates due to difficulty in controlling spray patterns and parallelism

Engineering Contradiction:

Improvegap distance controlVSAvoidspray deposition control

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent replaces the spray deposition process with a mechanical insertion method where stop members are physically placed into recesses in the jaw members. This mechanical approach provides precise control over gap distance while eliminating the manufacturing complexities of spray pattern control and parallelism alignment.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If clamping pressure alone is used to procure proper sealing thickness, then device complexity is reduced, but manufacturing precision deteriorates due to inability to control gap tolerances and parallelism

Engineering Contradiction:

Improvesealing mechanismVSAvoidgap tolerance control

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The sealing mechanism is segmented into multiple functional elements: jaw members for clamping, stop members for gap distance control, and insulative members for electrical isolation. This segmentation allows each component to perform its specific function with high precision while maintaining overall system simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The stop members act as intermediary elements between the jaw members, providing a mechanical reference that ensures proper gap distance and parallelism. These intermediaries translate the simple clamping action into precise control of sealing parameters without requiring complex active control systems.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If insulative member is housed in cavity of jaw member, then reliability is improved through consistent gap maintenance, but device complexity increases due to additional components and assembly steps

Engineering Contradiction:

Improvetissue sealing consistencyVSAvoidend effector assembly

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The insulative member is nested within a cavity in the jaw member, with the stop member inserted into a recess in the insulative member. This nested arrangement provides consistent gap maintenance and reliable tissue sealing while minimizing the space required and reducing the number of external components.

Inventive Principle:

Principle #7Nested doll (Nesting)

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

This solution enables effective and consistent tissue sealing by maintaining optimal pressure and gap distance, preventing tissue shredding or incomplete sealing, and ensuring a uniform seal across various tissue types.

Implementation Method 1

At least one of the proximal and distal ends extends a fixed distance toward the second jaw member such that the end and the second jaw member form a gap between electrically conductive surfaces

Methodology Applied

Scientific EffectMechanical constraint:

Implementation Method 2

Electrosurgical forceps utilize both mechanical clamping action and electrical energy to effect hemostasis by heating the tissue and blood vessels

Methodology Applied

Scientific EffectResistive heating: Joule Heating

Data Source

PatentUS7877853B2Method of manufacturing end effector assembly for sealing tissue

Publication Date: 2011.02.01 COVIDIEN LP

AI summary

A method for manufacturing an end effector assembly for sealing tissue includes the initial step of providing first and second electrically conductive sealing plates. The method also includes the steps of: encasing at least one of the electrically conductive sealing plates in a substantially moldable insulative material; applying a load to the electrically conductive sealing plates; allowing the insulative material to deform to create a gap between the sealing plates between about 0.001 inches to about 0.010 inches; and allowing the insulative material to cure.