Biomaterial Database

Affinity pump system: a new peristaltic blood pump for cardiopulmonary bypass. 2000

C Jaggy, and M Lachat, and B Leskosek, and G Zünd, and M Turina

Clinic for Cardiovascular Surgery, University Hospital, Zurich, Switzerland.

An in vitro study has been carried out to assess the pump performance of a new peristaltic, extracorporeal displacement pump (Affinity) for cardiopulmonary bypass. The pump system consists of a pump rotor (0-110 rpm), a pump chamber, a venous reservoir with a 5/8" connecting tube and the Affinity console. The polyurethane chamber is connected to the venous reservoir by a 5/8" tube and fills passively due to the hydrostatic pressure exhibited by the fluid height in the venous reservoir. The implementation of an occlusive segment in the pump chamber, which collapses in low filling states, should prevent significant negative pressures. An in vitro circuit was filled with bovine blood (37 degrees C, hematocrit 35%) and the pump flow was measured by an ultrasonic transit time flow probe with respect to pre-load, diameter and length of attached tubing in the venous line, pump speed (rpm) and size of the connecting tube (3/8" and 5/8"). At 108 rpm and a preload equal to 10 mmHg, the flow was 8.6 +/- 0.42 l/min for an afterload of 80 mmHg. The reduction of the inlet connector to 3/8" diminished the pump flow significantly to 5.2 +/- 0.31 l/min (p < 0.0001). The pump flow decreased linearly with respect to the length of the attached tube in the venous line and for a 2 m long 5/8" silicon tube, the rpm-optimized flow was still 6.0 +/- 0.28 l/min at a preload of 10 mmHg. In case of low filling state or too high rpm, the occlusive segment collapsed and no cavitation bubbles could be detected. Our in vitro measurements yield a nomogram for rpm-optimized blood flow with respect to the pre-load in the venous reservoir. The delivered 5/8"connecting tube facilitates optimum filling of the pump chamber for high blood flow, but limits the use of venous reservoirs to Affinity products. The pump yields a high blood flow even when long tubing in the venous line is used. This makes the pump a candidate for a ventricular assist device. In hypovolemia or high rpm, the occlusive segment collapses and no negative pressure is generated at the inflow site of the pump chamber.

UI	MeSH Term	Description	Entries
D002315	Cardiopulmonary Bypass	Diversion of the flow of blood from the entrance of the right atrium directly to the aorta (or femoral artery) via an oxygenator thus bypassing both the heart and lungs.	Heart-Lung Bypass,Bypass, Cardiopulmonary,Bypass, Heart-Lung,Bypasses, Cardiopulmonary,Bypasses, Heart-Lung,Cardiopulmonary Bypasses,Heart Lung Bypass,Heart-Lung Bypasses
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D004867	Equipment Design	Methods and patterns of fabricating machines and related hardware.	Design, Equipment,Device Design,Medical Device Design,Design, Medical Device,Designs, Medical Device,Device Design, Medical,Device Designs, Medical,Medical Device Designs,Design, Device,Designs, Device,Designs, Equipment,Device Designs,Equipment Designs
D004869	Equipment Safety	Freedom of equipment from actual or potential hazards.	Device Safety,Hazards, Equipment,Medical Device Safety,Safety, Equipment,Device Safety, Medical,Safety, Medical Device,Equipment Hazard,Equipment Hazards,Hazard, Equipment,Safety, Device
D005112	Extracorporeal Circulation	Diversion of blood flow through a circuit located outside the body but continuous with the bodily circulation.	Circulation, Extracorporeal,Circulations, Extracorporeal,Extracorporeal Circulations
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia