Miniature Pump for Treatment of Refractory Ascites Based on Local Magnetic Actuation

Abstract

This paper presents the design, fabrication, and experimental validation of a novel low-cost implantable pump for the treatment of refractory ascites (RA) based on local magnetic actuation (LMA). A reciprocating positive displacement pump displaces liquid unidirectionally through magnetic coupling with a magnetic controller placed on the outside of the patient's body. The proposed solution is intuitive to use given an alignment algorithm that exploits externally placed magnetic field sensors (MFS). The implantable device has a catheter-like shape, is electronic free (no on-board battery), has low fabrication cost (<8 USD), and is able to generate a flow-rate of 3.65 L/h while effectively pumping fluids with various viscosity (1–5.5 cP). RA is commonly treated via costly paracentesis or invasive surgical placement of a transjugular portosystemic shunt (TIPS). The proposed solution can be implanted with minimally invasive techniques and can be used on a daily basis to drain a set amount of liquid, without requiring recurrent hospital visits.