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Supplemental Digital Content is available in the text.Extracorporeal membrane oxygenation (ECMO) circuit volume, patient size, and blood flow may influence coagulation and hemolysis complications. We performed a single-center retrospective analysis of ECMO patients over a 6.5 year period. In 299 ECMO runs, 13% required coagulation-associated circuit changes. Respiratory ECMO was associated with coagulation-associated circuit changes [odds ratio (O/R) 2.8, p< 0.05] and developed severe (plasma-free hemoglobin [pfHb] > 100 mg/dl) hemolysis (O/R 2.3, p< 0.05). Severe hemolysis and component changes were associated with hospital mortality (O/R 2.3 and 2.5, respectively, p< 0.05). The activated partial thromboplastin time (aPTT) to residence time (RT) ratio (aPTT/RT) was used as a surrogate for coagulation risk. We found that aPTT/RT > 2.5 more than doubled time to circuit change (3–8 days, p< 0.05), but aPTT/RT > 3 increased bleeding risks and hospital mortality (O/R 1.8; p< 0.1). Hemolysis was associated with patient weight and circuit to patient volume ratio (CPVR) (p< 0.05), but not pump type. Hemolysis slightly increased with transfusion (p= 0.08), and transfusion requirements increased for CPVR >50% (p< 0.1).Our data suggest that pediatric respiratory ECMO patients are more likely to develop coagulation and hemolysis complications, which are associated with increased mortality. This may result from higher inflammatory processes, which affect coagulation and red cell fragility. Minimizing circuit volume, inflammation, and red cell stress may help to reduce these two complications and their associated mortality.

We investigated the safety and efficacy of surfactant during extracorporeal membrane oxygenation (ECMO) in children with cardiac disease. ECMO patients administered surfactant (surfactant group) were compared with patients who did not receive (control). Criteria to administer surfactant were based on a decreased lung compliance of <0.5 ml/kg/cm H2O. Efficacy was determined on pulmonary compliance change and the radiography-based respiratory distress severity (RDS) score. For the surfactant group, lung compliance measurements and RDS scores were obtained just before the first surfactant administration (T0), 24 hours after the last dose of surfactant (T1), and 24 hours after ECMO decannulation (T2). For the control group, measurements were obtained at baseline (T0), day of ECMO decannulation (T1), and 24 hours after ECMO decannulation (T2). Eighty were on ECMO, 29 in the surfactant, and 51 in the control group. Surfactant group was younger 20 (6–140) vs.28 (8–928) days old (p= 0.03), had longer ECMO duration 110 (58–192) vs.46 (29–84) hours (p= 0.001), and had longer mechanical ventilation 16 (11–26) vs.7 (5–9) days (p= 0.003). The lung compliance and RDS scores in the surfactant group improved significantly between baseline and 24 hours after decannulation, 0.36 ± 0.13 vs.0.5 ± 0.12 ml/kg/cm H2O (p= 0.002) and 13 ± 3 vs.12 ± 2 (p= 0.04), respectively. None developed pneumothorax. Mild pulmonary hemorrhage occurred twice (one in each group). Hospital duration and survival were similar 36 (19–48) vs.31 (18–48) days and 69% vs.78% in surfactant and control groups, respectively. Although this is a relatively small study, surfactant appears to be safe in pediatric cardiac ECMO patients.

Respiratory failure is a significant problem within the pediatric population. A means of respiratory support that readily allows ambulation could improve treatment. The Pittsburgh Pediatric Ambulatory Lung (P-PAL) is being developed as a wearable pediatric pump-lung for long-term respiratory support and has previously demonstrated positive benchtop results. This study aimed to evaluate acute (4–6 hours) in vivoP-PAL performance, as well as develop an optimal implant strategy for future long-term studies. The P-PAL was connected to healthy sheep (n = 6, 23–32 kg) viacannulation of the right atrium and pulmonary artery. Plasma-free hemoglobin (PfHb) and animal hemodynamics were measured throughout the study. Oxygen transfer rates were measured at blood flows of 1–2.5 L/min. All animals survived the complete study duration with no device exchanges. Flow limitation because of venous cannula occlusion occurred in trial 2 and was remedied viaan altered cannulation approach. Blood exiting the P-PAL had 100% oxygen saturation with the exception of trial 4 during which inadequate device priming led to intrabundle clot formation. Plasma-free hemoglobin remained low (<20 mg/dl) for all trials. In conclusion, this study demonstrated successful performance of the P-PAL in an acute setting and established the necessary methods for future long-term evaluation.

Supplemental Digital Content is available in the text.Acute and chronic respiratory failure are a significant source of pediatric morbidity and mortality. Current respiratory support options used to bridge children to lung recovery or transplantation typically render them bedridden and can worsen long-term patient outcomes. The Pittsburgh Pediatric Ambulatory Lung (P-PAL) is a wearable pediatric blood pump and oxygenator (0.3 m2surface area) integrated into a single compact unit that enables patient ambulation. The P-PAL is intended for long-term use and designed to provide up to 90% of respiratory support in children weighing 5–25 kg. Computational fluid dynamics and numerical gas exchange modeling were used to design the P-PAL and predict its performance. A P-PAL prototype was then used to obtain pressure versusflow curves at various impeller rotation rates using a blood analog fluid. In vitrooxygen exchange rates were obtained in blood in accordance with ISO standard 7199. The normalized index of hemolysis (NIH) was measured over a 6 hour period at blood flow rates of 1 and 2.5 L/min. The P-PAL provided blood flows of 1–2.5 L/min against the pressure drop associated with its intended-use pediatric cannulas. The oxygen exchange rate reached a maximum of 108 ml/min at a blood flow rate of 2.5 L/min and met our respiratory support design target. Device-induced hemolysis was low with NIH values of 0.022–0.027 g/100 L in the intended blood flow rate range. In conclusion, the current P-PAL design met our pumping, oxygenation, and hemolysis specifications and has the potential to improve treatment for pediatric respiratory failure.

Supplemental Digital Content is available in the text.Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has saved thousands of newborns. Population comparisons for research and quality initiatives require risk-matching, but no indices exist for this population. We sought to create a pre-ECMO risk index using the registry data from the Extracorporeal Life Support Organization. We analyzed 5,455 neonatal (<30 days old) respiratory VA-ECMO patients for the period 2000–2010. Multivariate regression examining the impact of pre-ECMO variables on survival to hospital discharge was performed to create the Pittsburgh Index for Pre-ECMO Risk (PIPER), which was ultimately was based on seven pre-ECMO variables. Each PIPER quartile demonstrated increasing mortality by 15% (R2= 0.98) and was associated with increased complications on ECMO. Further modeling to include on-ECMO complications (PIPER+), including complications and length of time on ECMO, increased the predictive power of the model, with 21% increases in mortality per PIPER+quartile (R2= 0.97). Our developed indices provide the first steps towards risk-adjusting patients for meaningful comparisons amongst patient populations. There may be additional clinically relevant measures, both pre- and on-ECMO, which could provide better predictive capability. Future work will focus on finding these additional measures and expansion of our techniques to include other patient populations.

Ventricular assist devices (VADs) are increasingly being used in pediatric patients to support cardiac failure. As more centers adopt this technology, there may be a need to transport these patients over long distances to facilitate patient care and organ transplantation. Food and Drug Administration indications for use state only that the patient must be a candidate for transplantation and does not place restrictions on the transplant capabilities of the implanting medical center. Nontransplanting institutions are able to use this technology with a predetermined agreement to transfer the patient to a partnering transplant center. We report the first two cases of interhospital air and ground transport of nonambulatory or intubated pediatric (<13 kg) patients supported by Berlin Heart EXCOR pediatric VADs and Ikus stationary drivers. We present our protocol for transporting this delicate patient population. In addition, we discuss important challenges encountered on these operations regarding vehicle transfers and the management of vehicle power supply. These two cases demonstrate that the transportation of pediatric patients on Berlin Heart VADs is feasible and safe and should be considered a treatment option in certain situations.

The Levitronix PediVAS is an extracorporeal magnetically levitated pediatric ventricular assist system with an optimal flow rate range of 0.3–1.5 L/min. The system is being tested in preclinical studies to assess hemodynamic performance and biocompatibility. The PediVAS was implanted in nine ovines for 30 days using either commercially available cannulae (n 3) or customized Levitronix cannulae (n 6). Blood biocompatibility in terms of circulating activated platelets was measured by flow cytometric assays to detect P-selectin. Platelet activation was further examined after exogenous agonist stimulation. Platelet activation increased after surgery and eventually returned to baseline in animal studies where minimal kidney infarcts were observed. Platelet activation remained elevated for the duration of the study in animals where a moderate number of kidney infarcts with or without thrombotic deposition in the cannulae were observed. When platelet activation did return to baseline, platelets appropriately responded to agonist stimulation, signifying conserved platelet function after PediVAS implant. Platelet activation returned to baseline in the majority of studies, representing a promising biocompatibility result for the Levitronix PediVAS.

The treatment of children with life-threatening cardiac and cardiopulmonary failure is a large and underappreciated public health concern. We have previously shown that the CentriMag is a magnetically levitated centrifugal pump system, having the utility for treating adults and large children (1,500 utilized worldwide). We present here the PediVAS, a pump system whose design was modified from the CentriMag to meet the physiological requirements of young pediatric and neonatal patients. The PediVAS is comprised of a single-use centrifugal blood pump, reusable motor, and console, and is suitable for right ventricular assist device (RVAD), left ventricular assist device (LVAD), biventricular assist device (BVAD), or extracorporeal membrane oxygenator (ECMO) applications. It is designed to operate without bearings, seals and valves, and without regions of blood stasis, friction, or wear. The PediVAS pump is compatible with the CentriMag hardware, although the priming volume was reduced from 31 to 14 ml, and the port size reduced from 3/8 to ¼ in. For the expected range of pediatric flow (0.3–3.0 L/min), the PediVAS exhibited superior hydraulic efficiency compared with the CentriMag. The PediVAS was evaluated in 14 pediatric animals for up to 30 days, demonstrating acceptable hydraulic function and hemocompatibility. The current results substantiate the performance and biocompatibility of the PediVAS cardiac assist system and are likely to support initiation of a US clinical trial in the future.