Study on the Development of Two-Stage Centrifugal Blood Pump for Cardiopulmonary Support System

Abstract

In the cardiopulmonary support system with an ECMO (extracorporeal membrane oxygenation), a higher pump head is demanded for a blood pump. In order to realize a blood pump with higher pump head, higher anti-hemolysis and thrombosis performances, a study on the development of unprecedented multistage blood pump was conducted. In consideration of the application of the blood pump for pediatric patients, a miniature two-stage centrifugal blood pump with the impeller's diameter of 40mm was designed and the performance was examined in experiments and computations. Some useful knowledge for a design of the blood pump with higher anti-hemolysis and thrombosis performances was obtained.

Improvement of Two-Stage Centrifugal Blood Pump for Cardiopulmonary Support System and Evaluation of Anti-Hemolysis Performance

“…The reference rotational speeds of the first prototype which was designed in the previous study [1] and the pump which is improved in the present study are the same and 4000rpm. The first prototype and the improved pump are called Prototype 1 and 2, respectively, in the present study.…”

“…1 Experimental apparatus for the measurement of pump performance and pressure distribution the design method of the blood pump has not been established yet because the type number of the blood pump is generally low and the internal flow tend to be complex, and moreover the conditions of the occurrence of the hemolysis and the thrombosis are not clear quantitatively as the characteristics of the blood are individually different. Therefore, based on the design method for general industrial centrifugal pumps [4], the authors designed a two-stage centrifugal blood pump (Prototype 1) in the previous study [1], using the knowledge for the suppression of the hemolysis and the thrombosis in single stage blood pumps. The flow rate, the pump head, and the rotational speed at the design point are 3L/min, 500mmHg, and 4200rpm, respectively.…”

“…The cross-sections of Prototype 1 are shown in Fig.4. The geometry of the pump is briefly explained in the present paper as the details have been commented in the reference [1]. The cross-sections from A to F in Fig as small as 40mm.…”

“…In order to realize a blood pump with higher pump head, higher anti-hemolysis and thrombosis performances, the authors try to develop an unprecedented two-stage centrifugal blood pump. In the previous study [1], the prototype of the two-stage blood pump was designed, problems to solve were revealed, and some ideas for improving the anti-hemolysis performance were suggested.…”

“…In the present study, the blood pump which was expected to have high anti-hemolysis and anti-thrombosis performances was designed using the knowledge obtained in the previous study [1], and the hemolysis test for the present pump and the previous prototype was carried out. The results of the hemolysis test and some useful knowledge for a design of blood pumps with higher anti-hemolysis and thrombosis performances are reported in the present paper.…”