Feasibility of a tiny centrifugal blood pump (TinyPump) for pediatric extracorporeal circulatory support

In this study, the performances of the TinyPump (priming volume 5 mL) system including the pediatric cannulae (Stöckert Pediatric Arterial Cannulae 2.6, 3.0, and 4.0 mm, Stöckert Instruments GmbH, Munich, Germany; Polystan 20-Fr Venous Catheter, MAQUET GmbH, Rastatt, Germany) and an oxygenator (Terumo Capiox RX05 Baby-RX, Terumo Cardiovascular Systems Co., Tokyo, Japan) were studied in vitro followed with preliminary ex vivo studies in 20-kg piglets. In vitro results revealed that the TinyPump system met the requirements for pump speed, pump flow, and pressure drop as extracorporeal circulatory support during open heart surgery and extracorporeal membrane oxygenation (ECMO) in pediatric patients. In 2-h ex vivo studies using 20-kg piglets where the blood contacting surface of the TinyPump was coated with a biocompatible phospholipid polymer, the plasma-free hemoglobin levels remained less than 5.0 mg/dL and no thrombus formation was observed inside the pump. The TinyPump system including the oxygenator and connecting circuits resulted in an overall priming volume of 68 mL, the smallest ever reported. The TinyPump can be a safe option for pediatric circulatory support during open heart surgery and ECMO without requiring blood transfusion.