Bi-Directional Blood Pump Impeller for Pressure-Matched Flow Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing blood pumps often operate in a single direction, requiring disconnection and reconnection for flow direction changes, leading to complications like bleeding and thrombus formation, and fail to match vein and artery pressure differentials effectively.
Innovation Solution
A bi-directional blood pump system with an impeller designed to rotate in opposite directions for antegrade and retrograde flows at the same speed, incorporating a filter trap and one-way valve to manage pressure and flow rates, and includes additional components like a gas exchanger and heat exchanger for enhanced functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If blood pumps operate in a single direction, then the pump structure can be simpler, but flow direction changes require disconnection and reconnection leading to complications
Solution Approach 1:
The pump is designed with an impeller that can dynamically rotate in both forward and reverse directions. The impeller blades are asymmetrically configured to efficiently move fluid in either direction of rotation, allowing the pump to switch between antegrade and retrograde flow modes without mechanical reconfiguration or disconnection of components.
2Adaptability or versatility
If blood pumps are designed for bi-directional operation, then flow direction can be changed without disconnection, but pressure matching between vein and artery becomes more difficult
Solution Approach 1:
The impeller features non-uniform blade geometry where different radial sections of the impeller have different blade angles and configurations. The outer radial portion has blades optimized for one direction while the inner radial portion has blades optimized for the opposite direction, allowing the pump to generate appropriate pressure characteristics for both antegrade and retrograde flow at the same rotational speed.
Solution Approach 2:
The impeller blades are designed with asymmetric geometry where the blade angle, curvature, and pitch vary circumferentially and radially. This asymmetric configuration creates different pressure gradients and flow characteristics depending on the direction of rotation, enabling the pump to naturally adapt its pressure output to match either arterial or venous pressure requirements without additional control mechanisms.
3Stress or pressure
If pump speed is changed between antegrade and retrograde flow, then pressure differential can be accounted for, but operational complexity and risk of complications increase
Solution Approach 1:
The pump system automatically adapts to the required flow direction and pressure conditions through the impeller's asymmetric blade geometry. When the rotation direction is reversed, the impeller's varying radial blade configurations automatically generate the appropriate pressure differential for the new flow direction, eliminating the need for manual speed adjustments or complex control algorithms to compensate for pressure differences between antegrade and retrograde modes.
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
Enables seamless switching between perfusion and retroperfusion without pressure mismatches, reducing complications and enhancing blood flow management with integrated filtration and temperature control.
Implementation Method 1
The impeller is configured to rotate at a predetermined speed in a first rotary direction to generate fluid flow in the first flow direction at a first pressure and a first flowrate. The impeller is configured to rotate in a second rotary direction, opposite the first rotary direction, at the predetermined pump speed to generate fluid flow in the second flow direction at a second pressure and a second flowrate.
Implementation Method 2
The one-way valve may have two flexible members attached to the perforated wall. The two flexible members may be configured to engage each other in a closed position and separate from each other in an open position.
Implementation Method 3
The bi-directional blood pump systems may include a filter trap
Implementation Method 4
The bi-directional blood pump systems may include a gas exchanger
Implementation Method 5
The bi-directional blood pump systems may include a heat exchanger
Data Source
AI summary
A blood pump system switchable between a first flow direction and a second flow direction includes a filter trap and a blood pump. The blood pump has an impeller configured to rotate at a predetermined speed in a first rotary direction to generate fluid flow in the first flow direction at a first pressure and a first flowrate. The impeller is configured to rotate in a second rotary direction at the predetermined pump speed to generate fluid flow in the second flow direction at a second pressure and a second flowrate. The first flowrate and the first pressure are different from the second flowrate and the second pressure with the impeller operating at the predetermined pump speed. The filter trap includes a one-way valve configured to remain closed with fluid flow the first direction and to open with fluid flow in the second direction.