Multi-position Valve for Stable Endoscopic Fluid Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Endoscopic surgery in distensible organs like the uterus faces challenges with fluid distention, where uneven fluid flow can lead to organ collapse or intravasation due to changes in pressure, especially when surgical instruments are inserted or removed, causing disruptive changes in distention fluid pressure.
Innovation Solution
A surgical system with a multi-position valve that maintains consistent fluid flow impedance through the endoscope's working channel, using a single valve to control distention fluid pressure, ensuring the same impedance whether a surgical instrument is present or not, by directing fluid flow through different paths to mimic the impedance caused by the instrument's presence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a resector or surgical tool is inserted into the working channel, then tissue cutting or treatment can be performed, but the distention fluid flow is impeded causing disruptive changes in fluid pressure
Solution Approach 1:
A valve is introduced as an intermediary component in the fluid pathway to mediate between the distention fluid source and the working channel. The valve includes a flow path with a variable orifice that can adjust fluid flow impedance to compensate for the presence of surgical instruments in the working channel, thereby maintaining stable distention pressure while allowing instrument insertion for tissue cutting
Solution Approach 2:
The valve's orifice size is made variable to change fluid flow parameters dynamically. When a resector is inserted into the working channel, the valve adjusts the orifice size to maintain the same overall fluid flow impedance, preventing disruptive pressure changes while preserving the ability to perform tissue cutting operations
2Reliability
If the access port is closed to prevent instrument insertion, then fluid flow impedance is maintained, but the resector or surgical tool cannot be inserted into the working channel
Solution Approach 1:
The valve system is made dynamic with an adjustable orifice that can change its flow characteristics based on operational needs. The orifice can be positioned to provide high impedance when no instrument is present, and adjusted to provide lower impedance when a resector is inserted, allowing both consistent fluid flow maintenance and instrument insertion capability
3Reliability
If the orifice size is reduced to match instrument-induced impedance, then fluid pressure stability is improved, but the flow rate of distention fluid is reduced
Solution Approach 1:
The valve orifice is designed to provide just enough flow to maintain adequate distention pressure while compensating for instrument presence. The orifice size is optimized to balance two competing needs: limiting flow to maintain pressure stability when no instrument is present, while allowing sufficient flow when an instrument is inserted to prevent hypotension
Data Source
AI summary
A surgical system can include a first instrument defining a first channel and a second instrument receivable by the first channel. The second instrument can include a second channel. A valve coupled to the first instrument controls fluid flow through the first channel. The valve has at least two positions and in one position, the impedance of fluid flow through the valve into the first channel (when the second instrument is not received in the first channel) is substantially the same as when the valve is the other position and the first channel partially blocked by the second instrument. In another aspect, a surgical system can include an outer member and the first instrument can be received within the outer member to define a second channel there between. The first instrument can include a visualization system and an illumination system.