First serial in vivo results of mechanical circulatory support in children with a new diagonal pump

Objectives: Mechanical circulatory support (MCS) is a rescue therapy for infants and children suffering from severe cardiorespiratory failure with specific system-related complications like bleeding, thromboembolism and device failure. Novel circuit components for temporary MCS with improved haemodynamic properties may improve patients' outcome and reduce system-related morbidities. The Deltastream DP3 (Medos Medizintechnik AG, Stolberg, Germany) is a newly designed rotational pump with a diagonally streamed impeller that can be used in children of all ages (priming volume 16 ml, flow 0-8 l/min). The aim of this study was to analyse the feasibility and safety of the DP3 pump system in children.

Methods: We retrospectively investigated a consecutive series of 16 children [median age 0.9 months (0.1-55 months), median weight 3.2 kg (2.5-14 kg)]. The DP3 circuit was used 22 times in these children for different indications: (I) extracorporeal life support (ECLS) in post-cardiotomy heart failure (n = 11), (II) ECLS in cardiopulmonary resuscitation (CPR) (n = 7) and (III) extracorporeal membrane oxygenation (ECMO) in acute respiratory distress syndrome (ARDS) (n = 4).

Results: Median duration of MCS was 4 days (0-18 days), 12 patients (75%) were weaned successfully from MCS, 4 of these children (25%) died after weaning, with a median survival time of 15 days (6-28 days). Overall survival rate was 50% and all 8 survivors were discharged home without neurological injury. There was no case of severe bleeding, thromboembolic complications or device failure. Mean lactate dehydrogenase (LDH) before MCS was 700 (±384) U/l, and increased to a maximum of 2279 (±2635) U/l during MCS (P = 0.04). Baseline D-dimer values were 3.4 (±3.0) mg/l and rose significantly to 19.5 (±11.5) mg/l during MCS (P < 0.001). The mean of the highest plasma-free haemoglobin during MCS was 21.0 (±42.9) mg/dl. The increase in plasma-free haemoglobin correlated moderately with the duration of MCS (Pearson's r: 0.78).

Conclusion: The use of the Deltastream DP3 seems to be safe and effective for MCS in children and may show a low degree of haemolysis. We observed no system-related complications and an overall good outcome in this demanding patient cohort.