Tubular Vacuum‐Powered Blood‐Pumping Device with Active Valves

Abstract

We propose a new vacuum-driven blood pump having a tubular shape with active valves. This design avoids any possible problems caused by membrane breakage, thereby minimizing the risk of gas embolic events and stagnation regions. By using active valves, it is possible to ensure better flow control and minimize pressure gradients inside and outside the pump. The low cost of the pump's disposable parts enables it to be used for such applications as a ventricular assist device, a pulsatile pump device in extracorporeal circulation, a pump in hemodialysis and apheresis circuits, and a pump in extracorporeal membrane oxygenator systems.

Continuous venovenous renal replacement therapy using a pulsatile blood pump

“…However, pulsatile pumps have not yet been used for continuous venovenous renal replacement therapy in humans. Our group has designed a new, easy-tohandle, vacuum-driven, tubular, blood pumping device that can be used with a wide range of blood flows [11].…”

“…In this situation, roller pumps automatically increase the pressure, within certain limits, to maintain the same blood flow. However, the pulsatile pump does not autoregulate the pressure and, when resistance develops in the circuit, the blood flow decreases [11]. For this reason, it is important to use very sensitive flow sensor systems and alarms to allow the physician to modify the pressure and/or frequency of pulsation according to the changes in blood flow.…”

“…A vacuum-driven, tubular, blood-pumping device, designed and patented by Madrid Community (Spain), was used [11]. The pump is a tubular device with a rigid external chamber and a flexible internal membrane that inflates and deflates due to the vacuum produced by a continuous aspiration system, simulating ventricular systole and diastole.…”

Continuous Renal Replacement Therapy With a Pulsatile Tubular Pump: Parameters Must Be Adjusted in Each Case

“…A pulsatile pump designed and patented by the Community of Madrid (Spain) was used (9). The characteristics of this pump have been described previously (10,11).…”

“…However, pulsatile pumps have still not been used for CRRT in clinical practice. Our group has designed a pulsatile tubular pump that has demonstrated its efficacy in experimental models as a pump for CRRT (9)(10)(11). In a previous study with a prototype of the pump, we demonstrated that the ultrafiltrate flow increases with increasing catheter diameter, BF, pump frequency, and diastolic time (11).…”