Double-Chamber Syringe Mixing Anesthetic pH Stability

Solution Overview

Problem

Existing local anesthetic dispensing devices are inefficient and cumbersome, requiring on-site manual mixing of bicarbonate with anesthetics, leading to increased preparation time, potential pH instability, and waste due to bulk preparation and repeated mixing steps.

Innovation Solution

A syringe system with a dual-stemmed plunger and double-chambered carpules that allows simultaneous and calibrated mixing of anesthetic and sodium bicarbonate solutions within a mixing chamber before administration, eliminating the need for pre-mixing and ensuring consistent pH control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If manual mixing of bicarbonate with anesthetic is performed on-site, then pH buffering can be achieved, but preparation time increases and technique complexity increases

Engineering Contradiction:

ImprovepH buffering effectivenessVSAvoidpreparation time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The anesthetic and bicarbonate solutions are pre-filled in separate carpules before use. The mixing chamber and delivery system are pre-assembled in the syringe device. When needed, the practitioner simply activates the plunger to automatically mix and deliver the buffered anesthetic, eliminating on-site mixing preparation time while maintaining pH buffering effectiveness.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The device performs automatic mixing of the anesthetic and bicarbonate solutions through the activated plunger mechanism that simultaneously pushes both carpules into the mixing chamber. The system self-regulates the mixing process and delivers the buffered solution without requiring manual technique, reducing both preparation time and technique complexity.

Inventive Principle:

Principle #25Self-service

2Productivity

If buffered anesthetic solution is prepared in bulk, then subsequent administrations can be provided, but pH decreases and activity diminishes over time

Engineering Contradiction:

Improvesubsequent administration capabilityVSAvoidpH stability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The device uses separate carpules for anesthetic and bicarbonate solutions rather than pre-mixing them in bulk. Each carpule remains sealed and stable until use. When needed, the solutions are mixed fresh in the mixing chamber and delivered immediately, ensuring pH stability while enabling subsequent administrations through the reusable syringe device with replaceable carpules.

Inventive Principle:

Principle #1Segmentation

3Reliability

If freshly mixed buffered anesthetic solutions are prepared for subsequent administrations, then pH stability is maintained, but preparation steps must be repeated

Engineering Contradiction:

ImprovepH stabilityVSAvoidrepeated preparation time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The anesthetic and bicarbonate solutions are pre-filled in separate carpules and the mixing chamber is pre-assembled in the syringe device. When needed, the practitioner simply activates the plunger to automatically mix and deliver the buffered anesthetic, eliminating on-site mixing preparation time while maintaining pH buffering effectiveness.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The device performs automatic mixing of the anesthetic and bicarbonate solutions through the activated plunger mechanism that simultaneously pushes both carpules into the mixing chamber. The system self-regulates the mixing process and delivers the buffered solution without requiring manual technique, reducing both preparation time and technique complexity.

Inventive Principle:

Principle #25Self-service

4Ease of operation

If separate chambers for each fluid are used in mixing syringes, then mixing capability is provided, but device complexity increases and prefabricated carpule compatibility is lost

Engineering Contradiction:

Improvemixing capabilityVSAvoidsyringe structure

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The device uses separate carpules for anesthetic and bicarbonate solutions rather than pre-mixing them in bulk. Each carpule remains sealed and stable until use. When needed, the solutions are mixed fresh in the mixing chamber and delivered immediately, ensuring pH stability while enabling subsequent administrations through the reusable syringe device with replaceable carpules.

Inventive Principle:

Principle #1Segmentation

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 reduces preparation time, minimizes waste, and ensures freshly mixed anesthetic solutions are administered at calibrated increments, maintaining pH stability and improving efficiency in clinical settings.

Implementation Method 1

depressing or actuating the plunger causes piercing of the carpule or a cap or sealed end of the carpule, to deliver a predetermined amount or volume of drug and second injectable fluid to be thoroughly mixed in the mixing chamber

Methodology Applied

Scientific EffectPressure-driven fluid flow: Pressure Gradient

Implementation Method 2

a mixing chamber in communication with the carpule-piercing means for receiving and adequately mixing the fluids dispensed from the pierced carpule chambers

Methodology Applied

Scientific EffectMixing: Stirring

Data Source

PatentUS10420888B2Double-chamber mixing syringe and method of use

Publication Date: 2019.09.24 PHARMAPHDII LLC

AI summary

Described is a syringe housing at least one removable carpule containing at least two injectable solutions and having a mixing chamber for mixing two injectable solutions during administration of the solutions, and methods of using the syringe.