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The article discusses advancements in the extracorporeal life support (ECLS) systems with pulsatile flow. Topics include decline in mortality by respiratory failure due to circuit improvement in ECLS' oxygenators and pumps; several changes in the ECLS systems such as low priming volume, low set-up time, and improved safety; and advantages of electrocardiogram (ECG) synchronized pulsatile flow like end-organ protection, increase coronary artery flow, and left ventricular function preservation.

Respiratory failure is one of the major causes of mortality and morbidity all over the world. Therapeutic options to treat respiratory failure remain limited. The objective of this study was to evaluate the gas transfer performance of a newly developed miniature portable integrated pediatric pump-lung device (PediPL) with small membrane surface for respiratory support in an acute ovine respiratory failure model. The respiratory failure was created in six adult sheep using intravenous anesthesia and reduced mechanical ventilation at 2 breaths/min. The PediPL device was surgically implanted and evaluated for respiratory support in a venovenous configuration between the right atrium and pulmonary artery. The hemodynamics and respiratory status of the animals during support with the device gas transfer performance of the PediPL were studied for 4 h. The animals exhibited respiratory failure 30 min after mechanical ventilation was reduced to 2 breaths/min, indicated by low oxygen partial pressure, low oxygen saturation, and elevated carbon dioxide in arterial blood. The failure was reversed by establishing respiratory support with the PediPL after 30 min. The rates of O2 transfer and CO2 removal of the PediPL were 86.8 and 139.1 mL/min, respectively. The results demonstrated that the PediPL (miniature integrated pump-oxygenator) has the potential to provide respiratory support as a novel treatment for both hypoxia and hypercarbia. The compact size of the PediPL could allow portability and potentially be used in many emergency settings to rescue patients suffering acute lung injury. [ABSTRACT FROM AUTHOR]

Veno-venous extracorporeal lung assist ( ECLA) can provide sufficient gas exchange even in most severe cases of acute respiratory distress syndrome. Commercially available systems are manually controlled, although an automatically controlled ECLA could allow individualized and continuous adaption to clinical requirements. Therefore, we developed a demonstrator with an integrated control algorithm to keep continuously measured peripheral oxygen saturation and partial pressure of carbon dioxide constant by automatically adjusting extracorporeal blood and gas flow. The ' SmartECLA' system was tested in six animal experiments with increasing pulmonary hypoventilation and hypoxic inspiratory gas mixture to simulate progressive acute respiratory failure. During a cumulative evaluation time of 32 h for all experiments, automatic ECLA control resulted in a peripheral oxygen saturation ≥90% for 98% of the time with the lowest value of 82% for 15 s. Partial pressure of venous carbon dioxide was between 40 and 49 mm Hg for 97% of the time with no value <35 mm Hg or >49 mm Hg. With decreasing inspiratory oxygen concentration, extracorporeal oxygen uptake increased from 68 ± 25 to 154 ± 34 mL/min ( P < 0.05), and reducing respiratory rate resulted in increasing extracorporeal carbon dioxide elimination from 71 ± 37 to 92 ± 37 mL/min ( P < 0.05). The ' SmartECLA' demonstrator allowed reliable automatic control of the extracorporeal circuit. Proof of concept could be demonstrated for this novel automatically controlled veno-venous ECLA circuit. [ABSTRACT FROM AUTHOR]

Background: Extracorporeal membrane oxygenation (ECMO) has salvaged many people's life during global pandemics. However, ECMO is associated with a high incidence of hemostatic complications. This study aims to explore the effects of the ECMO system on the coagulation system in the healthy ovine ECMO model., Methods: Ten healthy male sheep were included. Five received the veno-arterial ECMO and five received the veno-venous ECMO. Heparin was infused for systemic anticoagulation and was adjusted according to the activated clotting time. Blood routine tests, coagulation factors, anticoagulation proteins, and fibrinolysis markers were tested at the baseline and every 24 h. After weaning, the pump heads were dissected to explore thrombosis., Results: Platelets decreased in the first 72 h and returned to the baseline at the 120th hour. The neutrophils increased in the first 24 h and returned to the baseline at the 48th hour. Factors II, VII, and X decreased in the first 24 h and gradually increased, while factors VIII, IX, XI, and XII decreased in the first 24 h and remained at a low level. The baseline antithrombin was 73.2 ± 14.4% and reduced to 42.6 ± 9.9% at the 168th hour. Pathology showed seven sheep developed thrombus, but no clinically relevant bleeding or thrombosis events occurred., Conclusions: The study explored hemostatic alterations during ECMO in healthy animal models, which eliminated the confounding under critically ill conditions. The study may provide insights into ECMO hemostatic disorders and aid the design of optimal therapeutic strategies., (© 2022 International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Background: Veno-arterial extracorporeal life support (V-A ECLS) has become a cornerstone in the management of critical cardiogenic shock, but it can also precipitate organ injury, e.g., acute kidney injury (AKI). Available studies highlight the effect of non-cardiac organ injury on patient outcomes. Only very little is known about the impact of non-cardiac organ recovery on patient survival. AKI occurs frequently during cardiogenic shock and carries a poor prognosis. We have developed descriptive models to hypothesize on the role of AKI severity versus that of recovery of renal function for patient survival., Methods: Retrospective, observational study including 175 patients who were successfully decannulated from V-A ECLS. We assessed AKI severity using the "Kidney Disease: Improving Global Outcomes" (KDIGO) criteria. We defined recovered or preserved renal function (RPRF) prior to decannulation from V-A ECLS as 0 (AKI with no improvement) or 1 (no AKI or AKI with improvement). We classified patient outcomes as alive or dead at hospital discharge., Results: 78% (n = 138) of all patients survived hospital discharge of which 38% (n = 67) never developed AKI. After adjusting for shock severity and non-renal organ injury, RPRF emerged as an independent predictor of survival in both the overall cohort [OR (95% CI) - 4.11 (1.72-9.79)] and the AKI-only sub-cohort [OR (95% CI) - 5.18 (1.8-14.92)]. Neither maximum KDIGO stage nor KDIGO stage at the end of V-A ECLS was independently associated with survival., Conclusions: Our model identifies RPRF, but not AKI severity, as an independent predictor of hospital survival in patients undergoing V-A ECLS for cardiogenic shock. We hypothesize that recovered or preserved non-cardiac organ function during V-A ECLS is crucial for patient survival., (© 2022 International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Background: The impact of etiologies of acute fulminant myocarditis (AFM), which requires extracorporeal membrane oxygenation (ECMO), on clinical outcomes remains unknown. This study aimed to investigate the risk factors for ECMO weaning and mortality among patients with AFM due to viral etiologies in a tertiary referral medical center., Methods: We included 33 adults with AFM who received ECMO and were admitted between January 2002 and January 2021. General demographics, laboratory data, echocardiography findings, and long-term outcomes were analyzed for confirmed viral etiology and unconfirmed etiology groups., Results: The overall hospital survival rate was 54.5%. The age, sex, severity of the hemodynamic condition, and cardiac rhythm were similar between the two groups. Multivariate Cox regression analysis revealed that a confirmed viral etiology (HR 4.201, 95% CI 1.061-16.666), peri-ECMO renal replacement therapy (RRT) (HR 9.804, 1.140-83.333) and a high positive end-expiratory pressure (PEEP) in the ventilator settings at 24 h after ECMO (HR 1.479, 1.020-2.143) were significant prognostic factors for in-hospital mortality. Peri-ECMO RRT was also a significant negative prognostic factor for successful ECMO weaning (OR 0.061, 0.006-0.600) in the multivariate logistic model., Conclusions: Among AFM patients receiving ECMO support, RRT use was associated with a decreased chance of survival to ECMO weaning. Multiple organ dysfunction and a high PEEP were also predictive of a lower chance of hospital survival. Those with a confirmed diagnosis of viral myocarditis may require more medical attention due to the higher risk of hospital mortality than those without a definite diagnosis., (© 2022 International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Background: The centrifugal blood pump volute has a significant impact on its hemodynamic performance hemocompatibility. Previous studies about the effect of volute design features on the performance of blood pumps are relatively few., Methods: In the present study, the computational fluid dynamics (CFD) method was utilized to evaluate the impact of volute design factors, including spiral start position, volute tongue radius, inlet height, size, shape and diffuser pipe angle on the hemolysis index and thrombogenic potential of the centrifugal blood pump., Results: Correlation analysis shows that flow losses affect the hemocompatibility of the blood pump by influencing shear stress and residence time. The closer the spiral start position of the volute, the better the hydraulic performance and hemocompatibility of the blood pump. Too large or too small volute inlet heights can worsen hydraulic performance and hemolysis, and higher volute inlet height can increase the thrombogenic potential. Small volute sizes exacerbate hemolysis and large volute sizes increase the thrombogenic risk, but volute size does not affect hydraulic performance. When the diffuser pipe is tangent to the base circle of the volute, the best hydraulic performance and hemolysis performance of the blood pump is achieved, but the thrombogenic potential is increased. The trapezoid volute has poor hydraulic performance and hemocompatibility. The round volute has the best hydraulic and hemolysis performance, but the thrombogenic potential is higher than that of the rectangle volute., Conclusion: This study found that the hemolysis index shows a significant correlation with spiral start position, volute size, and diffuser pipe angle. Thrombogenic potential exhibits a good correlation with all the studied volute design features. The flow losses affect the hemocompatibility of the blood pump by influencing shear stress and residence time. The finding of this study can be used to guide the optimization of blood pump for improving the hemodynamic performance and hemocompatibility., (© 2022 International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Background: A paucity of evidence exists regarding the risks and benefits of Extracorporeal Membrane Oxygenation (ECMO) in adult kidney transplantation., Methods: This was a systematic review conducted from Jan 1, 2000 to April 24, 2020 of adult kidney transplant recipients (pre- or post- transplant) and donors who underwent veno-arterial or veno-venous ECMO cannulation. Death and graft function were the primary outcomes, with complications as secondary outcomes., Results: Twenty-three articles were identified that fit inclusion criteria. 461 donors were placed on ECMO, with an overall recipient 12-month mortality rate of 1.3% and a complication rate of 61.5%, the majority of which was delayed graft function. Fourteen recipients were placed on ECMO intraoperatively or postoperatively, with infection as the most common indication for ECMO. The 90-day mortality rate for recipients on ECMO was 42.9%, with multisystem organ failure and infection as the ubiquitous causes of death. 35.7% of patients experienced rejection within 6 months of decannulation, yet all were successfully treated., Conclusions: ECMO use in adult kidney transplantation is a useful adjunct. Recipient morbidity and mortality from donors placed on ECMO mirrors that of recipients from standard criteria donors. The morbidity and mortality of recipients placed on ECMO are also similar to other patient populations requiring ECMO., (© 2022 International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Background: Antithrombogenicity of extracorporeal membrane oxygenation (ECMO) devices, particularly oxygenators, is a current problem, with numerous studies and developments underway. However, there has been limited progress in developing methods to accurately compare the antithrombogenicity of oxygenators. Animal experiments are commonly conducted to evaluate the antithrombogenicity of devices; however, it is challenging to maintain a steady experimental environment. We propose an innovative experimental animal model to evaluate different devices in a constant experimental environment in real-time., Methods: This model uses two venous-arterial ECMO circuits attached to one animal (one by jugular vein and carotid artery, one by femoral vein and artery) and real-time assessment of thrombus formation in the oxygenator by indocyanine green (ICG) fluorescence imaging. Comparison studies were conducted using three pigs: one to compare different oxygenators (MERA vs. CAPIOX) (Case 1), and two to compare antithrombotic properties of the oxygenator (QUADROX) when used under different hydrodynamic conditions (continuous flow vs. pulsatile flow) (Cases 2 and 3)., Results: Thrombi, visualized using ICG imaging, appeared as black dots on a white background in each oxygenator. In Case 1, differences in the site of thrombus formation and rate of thrombus growth were observed in real-time in two oxygenators. In Case 2 and 3, the thrombus region was smaller in pulsatile than in continuous conditions., Conclusions: We devised an innovative experimental animal model for comparison of antithrombogenicity in ECMO circuits. This model enabled simultaneous evaluation of two different ECMO circuits under the same biological conditions and reduced the number of sacrificed experimental animals., (© 2022 International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Background: The oxygen challenge test (OCT) is an underutilized measure of lung recovery, easily performed prior to proceeding with a trial-off V-V ECLS as part of a weaning algorithm. Evidence-based thresholds for OCT results which support continuing with V-V ECLS weaning are lacking, making interpretation of these tests challenging in clinical practice., Methods: We performed a retrospective review of patients commenced on V-V ECLS as a bridge-to-recovery at Vancouver General Hospital from 2015-2019. The absolute PaO 2 post-OCT and change in PaO 2 proportional to incremental FiO 2 change on the ventilator (∆PaO 2 ) were evaluated as predictive screening metrics for identifying conditions favorable for successful trial-off of V-V ECLS., Results: An optimal cut-off of PaO 2  ≥ 240 mm Hg post-OCT (AUC 0.77) and ∆PaO 2  ≥ 250 mm Hg (AUC 0.76) was identified as a threshold for predicting successful trials-off. A total of 26 and 24 patients achieved post-OCT PaO 2 and ∆PaO 2 thresholds, and 100% of these patients were liberated successfully from ECLS during their admission., Conclusions: The OCT can serve as an effective screen of shunt reduction and native lung recovery which can be used alongside other measures of ventilation to assess for suitability of liberation from V-V ECLS prior to a trial-off. Achieving a PaO 2  ≥ 240 mm Hg post-OCT is a strong prognostic indicator for successful liberation from V-V ECLS during ICU admission., (© 2022 International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

The effect of normothermic extracorporeal membrane oxygenation (NECMO) on small bowel preservation in a clinically relevant large animal model of expected donation after cardiac death (eDCD) was evaluated. Thirty domestic crossbred donor pigs were divided into five groups. The first group served as the live donation (LD) group, the second group served as the donation after cardiac death (DCD) group, and the remaining were further assigned into three subgroups: E1 group (1 h NECMO support), E3 group (3 h NECMO support), and E5 group (5 h NECMO support). Pathology, electron microscopy, energy metabolism, cell apoptosis, and tight junction (TJ) protein expression level of intestinal mucosa and the level of plasma d-lactic acid were evaluated in normal, cardiac death and at the end of extracorporeal support, respectively. The mean arterial pressure and PaO2 were maintained over 60 and 267 mm Hg during NECMO support, respectively. One hour of extracorporeal support could improve the energy status in intestines of the DCD group. Although the histologic damage and apoptosis of the E1 group had no significant difference with those of the LD and DCD groups ( P > 0.05), the levels of intestinal mucosa TJ protein decreased ( P < 0.05), and plasma d-lactic acid increased progressively ( P < 0.05). With the extension of extracorporeal support, the degree of intestinal mucosa damage and intestinal permeability gradually increased, as well as the content of adenosine triphosphate in intestinal mucosa. The normothermic extracorporeal support for 1 h in DCD is beneficial for improving the energy status and viability of the bowel. However, the integrity of intestinal mucosa was destroyed gradually as extracorporeal support time went by. And the activation of intestinal epithelial apoptosis and hyperoxia might be the factors that lead to intestinal mucosa injury. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is common in patients treated with veno-arterial (VA-) or veno-venous (VV-) extracorporeal membrane oxygenation (ECMO). In this setting, the use of continuous renal replacement therapy (CRRT) can help to optimize fluid status but may also negatively impact on patients' outcome. In contrast, the relationship between AKI, CRRT, and survival in critically ill adult patients receiving ECMO is not well defined. The institutional ECMO database ( n = 162) from November 2008 to December 2013, excluding patients with ICU survival <24 hours was reviewed. Demographics, co-morbidities, and concomitant therapies for all patients were collected. AKI was defined according to the Acute Kidney Injury Network (AKIN) criteria. ICU mortality was noted. Data were retrieved for 135 patients (79 with VA-ECMO and 56 with VV-ECMO). Of these, 95 developed AKI, 63 (47%) of whom required CRRT; thus three groups of patients were identified: (a) no AKI; (b) AKI without CRRT (AKINOCRRT); and (c) CRRT with AKI (AKICRRT). AKINOCCRT patients were more likely to have preexisting heart disease, to be more severely ill, and to be treated with VA-ECMO than those without AKI. AKICRRT patients were also more likely to be treated with VA-ECMO, had more organ dysfunction at the time of ECMO insertion, and needed more transfusions and inotropic agents than patients without AKI. ICU mortality was 53% (72/135) and was similar in the three groups, even when different AKI stages or VA/VV-ECMO were analyzed separately. In this study, the use of CRRT was not associated with an increased mortality in an adult population of patients treated with ECMO, even after adjustment for confounders. [ABSTRACT FROM AUTHOR]

It is essential to establish an appropriate initial treatment strategy for pediatric fulminant myocarditis. We reviewed eight cases of pediatric fulminant myocarditis that required extracorporeal membrane oxygenation (ECMO) from 2012 to 2015. The median age was 8 years (range 3 months-13 years), and the median body surface area was 0.89 m2 (range 0.35-1.34 m2). Peripheral veno-arterial ECMO was initially applied, and we evaluated whether heart decompression was sufficient. If the pump flow was insufficient, central cannulation was performed via median sternotomy (central ECMO). The need for subsequent ventricular assist device (VAD) support was determined 72 h after ECMO initiation. Six patients were bridged to recovery using peripheral ECMO support only (for 3-11 days), whereas two required VAD support. One patient was switched to central ECMO before VAD implantation. Three patients died of multiorgan failure, even though cardiac function recovered in two of those patients. The duration from hospital arrival to ECMO initiation was shorter in the survival (3.3 ± 1.3 h; range 1.6-4.7 h) than in the nonsurvival group (32 ± 28 h; range 0.7-55 h). Peripheral ECMO can be useful as a bridge to decision for pediatric fulminant myocarditis, which is frequently followed by a successful bridge to recovery. It is important to determine whether ECMO support should be initiated before organ dysfunction advances to preserve organ function, which provides a better bridge to subsequent VAD therapy and heart transplant or recovery. [ABSTRACT FROM AUTHOR]

Therapeutic plasma exchange ( TPE) is an extracorporeal blood purification technique designed for the removal of substances with large molecular weight from the plasma. However, it is not commonly performed in children and the elderly because of concern of potential complications. The Department of Nephrology at Zagreb University Hospital Centre's database (8335 procedures, 981 patients) was retrospectively analyzed from 1982 to 2011 to record indications, applications, and safety of TPE use in children (≤18 years), adults (>18 and <65 years), and elderly patients (≥65 years). Indications, blood access, replacement fluid, and anticoagulation during TPE differed among age groups. Significantly more complications were recorded in the youngest and eldest patients compared with the adults (12.2% and 12.7% vs. 9.9%, respectively), while the severity of complications did not differ significantly among the age groups. Our results indicate that TPE may be performed relatively safely in all age groups when the patients' differences are acknowledged prior to prescribing the procedure. [ABSTRACT FROM AUTHOR]

Early graft failure (EGF) is a major risk factor for death after heart transplantation (Htx). We investigated the predictive risk factors for moderate-to-severe EGF requiring an intra-aortic balloon pump (IABP) or extracorporeal membrane oxygenation (ECMO) circulatory support as treatment after Htx. Between January 2000 and December 2014, 412 consecutive adult patients underwent isolated Htx at our institution. Moderate and severe EGF were defined as the need for IABP and ECMO support, respectively, within 24 h after Htx. All available recipient and donor variables were analyzed to assess the risk of EGF occurrence. Overall, moderate-to-severe EGF occurred in 46 (11.1%) patients. Twenty-nine (63.04%) patients required peripheral or central ECMO support in the treatment of severe EGF and 17 (36.9%) patients required IABP support for the treatment of moderate EGF. The predictive risk factors for moderate-to-severe EGF in recipients, as assessed by logistic regression analysis, were a preoperative transpulmonary gradient > 12 mm Hg (odds ratio [OR] 5.2; P = 0.023), a preoperative inotropic score > 10 (OR 8.5; P = 0.0001), and preoperative ECMO support (OR 4.2; P = 0.012). For donors, the predictive risk factor was a donor score ≥ 17 (OR 8.3; P = 0.006). The absence of EGF was correlated with improved long-term survival: 94% at 1 year and 81% at 5 years without EGF versus 76% and 36% at 1 year ( P < 0.001), and 70% and 28% at 5 years ( P < 0.001) with EGF requiring IABP and ECMO support, respectively. In-hospital weaned and survived patients after IABP or ECMO treatment for moderate-to-severe EGF had a similar 5-year conditional survival rate as transplant patients who had not suffered EGF: 88% without EGF versus 84% with EGF treated with mechanical circulatory support devices ( P = 0.08). The occurrence of EGF is a multifactorial deleterious event that depends on donor and recipient profiles. IABP and ECMO support are reliable treatment strategies, depending on the grade of EGF. Furthermore, surviving patients treated with IABP or ECMO have the same long-term conditional survival rate as patients who have not suffered EGF. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about systematic venoarterial extracorporeal membrane oxygenation after surgical correction of post-infarcton ventricular septal defect.

Extracorporeal membrane oxygenation (ECMO) is used for severe acute respiratory distress syndrome. However, available ECMO systems are large and not well designed for fast delivery, emergency implantation, and interhospital transfer. Therefore, a new miniaturized oxygenator with integrated rotary blood pump (ILIAS) was developed and compared with a standard ECMO system in a large animal model. Acute lung injury was induced with repeated pulmonary saline lavage in 14 pigs until PaO2/ FiO2-ratio was <100 mm Hg with a positive-end-expiratorypressure of 5 mbar. Pigs were assigned to the following three groups: group 1 (n = 4): control group with conventional ventilation; group 2 (n = 5): standard vv-ECMO; group 3 (n = 5): vv-ILIAS. Gas exchange, hemodynamics, hemolysis, and coagulation activation were examined over a period of 8 h. No device failed during the observation period. PaCO2 decreased from 59.40 ± 4.14 mm Hg to 48.62 ± 4.50 mm Hg after 1 h in the ILIAS group compared with an improvement of PaCO2 from 48.86 ± 7.45 to 40.10 ± 6.02 in the conventional ECMO group (P = not significant [n.s.]). ARDS-induced respiratory acidosis was controlled promptly with a pH of 7.2 ± 0.1 at baseline increasing to 7.4 ± 0.1 in both study groups after 60 min of ECMO support. Mean carbon dioxide transfer was comparable between the conventional ECMO and ILIAS (211.36 ±78.39 mL/min vs. 219.99 ± 76.72 mL/min, P = n.s.). PaO2/FiO2 increased from 118.4 ± 15.5 mm Hg to 179.1 ± 72.4 mm Hg in the ILIAS group compared with an improvement of oxygenation from 107.1 ± 24.9 mm Hg to 179.0 ± 45.7 mm Hg in the standard ECMO group (P = n.s.). Mean oxygen transfer was calculated with 136.09 ± 30.25 mL/min for the ILIAS and 129.05 ± 36.28 mL/min for the standard ECMO. Hemodynamic instability or significant activation of the plasmatic coagulation was not observed. However, hemolysis was significantly higher in the ILIAS group compared with the conventional ECMO. As the ILIAS prototype provided excellent gas exchange with hemodynamic stability comparable with a standard ECMO system, we believe this study serves as a proof of concept. Further development and design modifications (optimized rotation speed and surface coating of rotor) are already done and another experiment is projected to reduce hemolysis and platelet consumption for clinical application. [ABSTRACT FROM AUTHOR]

Temporary extracorporeal membrane oxygenation (ECMO) has been established as an essential part of therapy in patients with pulmonary or cardiac failure. As physiological gaseous exchange is artificially altered in this patient group, it is debatable whether a 13C-breath test can be carried out. In this proof of technical feasibility report, we assess the viability of the 13C-breath test LiMAx (maximum liver function capacity) in patients on ECMO therapy. All breath probes for the test device were obtained directly via the membrane oxygenator. Data of four patients receiving liver function assessment with the 13C-breath test LiMAx while having ECMO therapy were analyzed. All results were compared with validated scenarios of the testing procedures. The LiMAx test could successfully be carried out in every case without changing ECMO settings. Clinical course of the patients ranging from multiorgan failure to no sign of liver insufficiency was in accordance with the results of the LiMAx liver function test. The 13C-breath test is technically feasible in the context of ECMO. Further evaluation of 13C-breath test in general would be worthwhile. The LiMAx test as a 13C-breath test accessing liver function might be of particular predictive interest if patients with ECMO therapy develop multiorgan failure. [ABSTRACT FROM AUTHOR]

Multipotent progenitor cells were mobilized during pediatric extracorporeal membrane oxygenation ( ECMO). We hypothesize that these cells also adhered onto polymethylpentene ( PMP) fibers within the membrane oxygenator ( MO) during adult ECMO support. Mononuclear cells were removed from the surface of explanted PMP- MOs ( n = 16). Endothelial-like outgrowth and mesenchymal-like cells were characterized by flow cytometric analysis using different surface markers. Spindle-shaped attaching cells were identified early, but without proliferative activity. After long-term cultivation palisading type or cobblestone-type outgrowth cells with high proliferative activity appeared and were characterized as (i) leukocytoid CD45+/ CD31+ ( CD133+/ VEGFR-II+/ CD90+/ CD14+/ CD146dim/ CD105dim); (ii) endothelial-like CD45−/ CD31+ ( VEGF-RII+/ CD146+/ CD105+/ CD133−/ CD14−/ CD90−); and (iii) mesenchymal-like cells CD45−/ CD31− ( CD105+/ CD90+/ CD133dim/ VEGFR-II−/ CD146−/ CD14−). The distribution of the cell populations depended on the MO and cultivation time. Endothelial-like cells formed capillary-like structures and did uptake Dil-acetylated low-density lipoprotein. Endothelial- and mesenchymal-like cells adhered on the surface of PMP- MOs. Further research is needed to identify the clinical relevance of these cells. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which include the extracorporeal membrane oxygenation for congenital heart disease, the history of cardiopulmonary bypass, and the infant jarvik 2015 ventricular assist device.

Acute renal failure ( ARF) is associated with increased mortality in pediatric extracorporeal membrane oxygenation ( ECMO). The aim of this study was to identify predictors of ARF during ECMO in pediatric patients after cardiac surgery. A retrospective study analyzed 42 children (≤15 years) after cardiac surgery requiring venous-arterial ECMO between December 2008 and December 2014 at Fuwai Hospital. ARF was defined as ≥300% rise in serum creatinine ( SCr) concentration from baseline or application of dialysis. Multivariate logistic regression was performed to identify the predictors of ARF during ECMO. A total of 42 children (age, interquartile range [ IQR], 13.0 [7.2-29.8] months; weight, IQR, 8.5 [6.7-11.0] kg) after cardiac surgery requiring ECMO were included in this study. The total survival rate was 52.4%, and the incidence of ARF was 40.5%. As the result of univariate analysis, ECMO duration, cardiopulmonary resuscitation, maximum free hemoglobin ( FHB) during ECMO, lactate level, and mean blood pressure before initiation of ECMO were entered in multiple logistic regression analysis. In multiple logistic regression analysis, FHB during ECMO ( OR 1.136, 95% CI 1.023-1.261) and lactate level before initiation of ECMO ( OR 1.602, 95% CI 1.025-2.502) were risk factors for ARF during ECMO after pediatric cardiac surgery. There was a linear correlation between maximum SCr and maximum FHB ( Pearson's r = 0.535, P = 0.001). Maximum SCr during ECMO has also a linear correlation with lactate level before initiation of ECMO ( Pearson's r = 0.342, P = 0.044). Increased FHB during ECMO and high lactate level before initiation of ECMO were risk factors for ARF during ECMO in pediatric patients after cardiac surgery. [ABSTRACT FROM AUTHOR]

The protective effects of ischemic postconditioning ( IPC) and nitric oxide ( NO) administration have been demonstrated in several ischemic scenarios. However, current evidence regarding the effect of IPC and NO in extracorporeal cardiopulmonary resuscitation remains lacking. Fifteen female swine (body weight 45 kg) underwent veno-arterial extracorporeal membrane oxygenation ( ECMO) implantation; cardiac arrest-ventricular fibrillation was induced by rapid ventricular pacing. After 20 min of cardiac arrest, blood flow was restored by increasing the ECMO flow rate to 4.5 L/min. The animals (five per group) were then randomly assigned to receive IPC (three cycles of 3 min ischemia and reperfusion), NO (80 ppm via oxygenator), or mild hypothermia ( HT; 33.0°C). Cerebral oximetry and aortic blood pressure were monitored continuously. After 90 min of reperfusion, blood samples were drawn for the measurement of troponin I, myoglobin, creatine-phosphokinase, alanine aminotransferase, neuron-specific enolase, cystatin C, and reactive oxygen metabolite ( ROM) levels. Significantly higher blood pressure and cerebral oxygen saturation values were observed in the HT group compared with the IPC and NO groups ( P < 0.05). The levels of troponin I, myoglobin, creatine phosphokinase, and alanine aminotransferase were significantly lower in the HT group ( P < 0.05); levels of neuron-specific enolase, cystatin C, and ROM were not significantly different. IPC and NO were comparable in all monitored parameters. The results of the present study indicate that IPC and NO administration are not superior interventions to HT for the maintenance of blood pressure, cerebral oxygenation, organ protection, and suppression of oxidative stress following extracorporeal cardiopulmonary resuscitation. [ABSTRACT FROM AUTHOR]

Extracorporeal membrane oxygenation ( ECMO) in our institution resulted in near total mortality prior to the establishment of an algorithm-based program in July 2010. We hypothesized that an algorithm-based ECMO program improves the outcome of patients with acute myocardial infarction complicated with cardiogenic shock. Between March 2003 and July 2013, 29 patients underwent emergent catheterization for acute myocardial infarction due to left main or proximal left anterior descending artery occlusion complicated with cardiogenic shock (defined as systolic blood pressure <90 mm Hg despite multiple inotropes, with or without intra-aortic balloon pump, lactic acidosis). Of 29 patients, 15 patients were treated before July 2010 ( Group 1, old program), and 14 patients were treated after July 2010 ( Group 2, new program). There were no significant differences in the baseline characteristics, including age, sex, coronary risk factors, and left ventricular ejection fraction between the two groups. Cardiopulmonary resuscitation prior to ECMO was performed in two cases (13%) in Group 1 and four cases (29%) in Group 2. ECMO support was performed in one case (6.7%) in Group 1 and six cases (43%) in Group 2. The 30-day survival of Group 1 versus Group 2 was 40 versus 79% ( P = 0.03), and 1-year survival rate was 20 versus 56% ( P = 0.01). The survival rate for patients who underwent ECMO was 0% in Group 1 versus 83% in Group 2 ( P = 0.09). In Group 2, the mean duration on ECMO was 9.8 ± 5.9 days. Of the six patients who required ECMO in Group 2, 100% were successfully weaned off ECMO or were bridged to ventricular assist device implantation. Initiation of an algorithm-based ECMO program improved the outcomes in patients with acute myocardial infarction complicated by cardiogenic shock. [ABSTRACT FROM AUTHOR]

This retrospective study reviews our results regarding the long-term support in pediatric patients using two ventricular assist systems between January 2008 and April 2014. We implanted the Berlin Heart EXCOR in 29 patients (median age 3.4 years [interquartile range ( IQR) 0.2-16.5], median weight 13 kg [ IQR 4.2-67.2]). Twenty-two patients (75.8%) received a left ventricular assist device. Three patients (10.3%) had single-ventricle physiology. One patient (3.4%) had mechanical mitral valve prosthesis. The HeartWare System was implanted in nine patients. The median age was 15.6 years ( IQR 12.2-17.9), and the median weight was 54.9 kg ( IQR 27.7-66). In the Berlin Heart group, the median support time was 65 days ( IQR 4-619), with 3647 days of cardiac support. Nineteen patients (65.5%) were transplanted, six patients (20.7%) recovered, one patient (3.4%) is on support, and three patients (10.3%) died on support. Survival rate was 89.7%. Fourteen blood pumps had been exchanged. Four patients (13.8%) had local signs of infection, and three patients (10.3%) had neurological complications. In the HeartWare group, the median support time was 180 days ( IQR 1-1124), with 2839 days of cardiac support. Four patients (44.4%) had local signs of infection, and three (33.3%) had neurological complications. Eight patients (88.9%) have been transplanted, and one patient (11.1%) died on support. Survival rate was 88.9%. Excellent survival is possible after long-term mechanical circulatory support in patients with two- and single-ventricle physiology with a low rate of adverse events. [ABSTRACT FROM AUTHOR]

Our objective is to describe the use of a ventricular assist device ( VAD) in single-ventricle patients with circulatory failure following superior cavopulmonary anastomosis ( SCPA). We performed a retrospective chart review of all single-ventricle patients supported with a VAD following SCPA. Implantation techniques, physiologic parameters while supported, medical and surgical interventions postimplant, and outcomes were reviewed. Four patients were supported with an EXCOR Pediatric ( Berlin Heart Inc., The Woodlands, TX, USA) following SCPA for a median duration of 10.5 days (range 9-312 days). Selective excision of trabeculae and chords facilitated apical cannulation in all patients without inflow obstruction. There were two pump exchanges in the one patient supported for 312 days. Two patients were evaluated by cardiac catheterization while supported. Three of four patients were successfully bridged to transplantation. One patient died while supported. All patients had significant bleeding at the time of transplantation, and one required posttransplant extracorporeal membrane oxygenation with subsequent full recovery. VAD support can provide a successful bridge to transplantation in patients with single-ventricle circulation following SCPA. A thorough understanding of the challenges encountered during this support is necessary for successful outcomes. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the effects of pulsatile and nonpulsatile extracorporeal membrane oxygenation (ECMO) on hemodynamic energy and systemic microcirculation in an acute cardiac failure model in piglets. Fourteen piglets with a mean body weight of 6.08 ± 0.86 kg were divided into pulsatile ( N = 7) and nonpulsatile ( N = 7) ECMO groups. The experimental ECMO circuit consisted of a centrifugal pump, a membrane oxygenator, and a pneumatic pulsatile flow generator system developed in-house. Nonpulsatile ECMO was initiated at a flow rate of 140 mL/kg/min for the first 30 min with normal heart beating, with rectal temperature maintained at 36°C. Ventricular fibrillation was then induced with a 3.5-V alternating current to generate a cardiac dysfunction model. Using this model, we collected the data on pulsatile and nonpulsatile groups. The piglets were weaned off ECMO at the end of the experiment (180 min after ECMO was initiated). The animals did not receive blood transfusions, inotropic drugs, or vasoactive drugs. Blood samples were collected to measure hemoglobin, methemoglobin, blood gases, electrolytes, and lactic acid levels. Hemodynamic energy was calculated using the Shepard's energy equivalent pressure. Near-infrared spectroscopy was used to monitor brain and kidney perfusion. The pulsatile ECMO group had a higher atrial pressure (systolic and mean), and significantly higher regional saturation at the brain level, than the nonpulsatile group (for both, P < 0.05). Additionally, the pulsatile ECMO group had higher methemoglobin levels within the normal range than the nonpulsatile group. Our study demonstrated that pulsatile ECMO produces significantly higher hemodynamic energy and improves systemic microcirculation, compared with nonpulsatile ECMO in acute cardiac failure. [ABSTRACT FROM AUTHOR]

In patients requiring left ventricular assist device ( LVAD) support, it can be difficult to ascertain suitability for long-term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support ( ECLS) as a bridge-to-bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end-organ dysfunction and reduce ventricular assist device ( VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous-flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty-three patients required ECLS support pre- LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end-organ function pre- VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end-organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these 'crash and burn' patients. [ABSTRACT FROM AUTHOR]

The objectives of this study were to investigate the relationship between revolution speed of a conventional centrifugal pump and negative pressure at the inlet of the pump by clamping the tubing upstream of the pump, and to verify whether negative pressure leads to gaseous microemboli ( GME) production in a simulated adult extracorporeal life support ( ECLS) system. The experimental circuit, including a Maquet Rotaflow centrifugal pump and a Medos Hilite 7000 LT polymethyl-pentene membrane oxygenator, was primed with packed red blood cells (hematocrit 35%). Negative pressure was created in the circuit by clamping the tubing upstream of the pump for 10 s, and then releasing the clamp. An emboli detection and classification quantifier was used to record GME volume and count at pre-oxygenator and post-oxygenator sites, and pressure and flow rate data were collected using a custom-based data acquisition system. All trials were conducted at 36°C at revolution speeds of 2000-4000 rpm (500 rpm increment). The flow rates were 1092.5-4708.4 mL/min at the revolution speeds of 2000-4000 rpm. Higher revolution speed generated higher negative pressure at the pre-pump site when clamping the tubing upstream of the pump (−108.3 ± 0.1 to −462.0 ± 0.5 mm Hg at 2000-4000 rpm). Moreover, higher negative pressure was associated with a larger number and volume of GME at pre-oxygenator site after de-clamp ( GME count 10 573 ± 271 at pre-oxygenator site at 4000 rpm). The results showed that there was a potential danger of delivering GME to the patient when clamping pre-pump tubing during ECLS using a centrifugal pump. Our results warrant further clinical studies to investigate this phenomenon. [ABSTRACT FROM AUTHOR]

Extracorporeal membrane oxygenation ( ECMO) has traditionally been and, for the most part, still is being performed using roller pumps. Use of first-generation centrifugal pumps has yielded controversial outcomes, perhaps due to mechanical properties of the same and the ensuing risk of hemolysis and renal morbidity. Latest-generation centrifugal pumps, using magnetic levitation (ML), exhibit mechanical properties which may have overcome limitations of first-generation devices. This retrospective study aimed to assess the safety and efficacy of veno-arterial ( V- A) ECMO for cardiac indications in neonates, infants, and children, using standard ( SP) and latest-generation ML centrifugal pumps. Between 2002 and 2014, 33 consecutive neonates, infants, and young children were supported using V- A ECMO for cardiac indications. There were 21 males and 12 females, with median age of 29 days (4 days-5 years) and a median body weight of 3.2 kg (1.9-18 kg). Indication for V- A ECMO were acute circulatory collapse in ICU or ward after cardiac repair in 16 (49%) patients, failure to wean after repair of complex congenital heart disease in 9 (27%), fulminant myocarditis in 4 (12%), preoperative sepsis in 2 (6%), and refractory tachy-arrhythmias in 2 (6%). Central cannulation was used in 27 (81%) patients and peripheral in 6. Seven (21%) patients were supported with SP and 26 (79%) with ML centrifugal pumps. Median duration of support was 82 h (range 24-672 h), with 26 (79%) patients weaned from support. Three patients required a second ECMO run but died on support. Seventeen (51%) patients required peritoneal dialysis for acute renal failure. Overall survival to discharge was 39% (13/33 patients). All patients with fulminant myocarditis and with refractory arrhythmias were weaned, and five (83%) survived, whereas no patient supported for sepsis survived. Risk factors for hospital mortality included lower (<2.5 kg) body weight ( P = 0.02) and rescue ECMO after cardiac repair ( P = 0.03). During a median follow-up of 34 months (range 4-62 months), there were three (23%) late deaths and two late survivors with neurological sequelae. Weaning rate (5/7 vs. 21/26, P = NS) and prevalence of renal failure requiring dialysis (4/7 vs. 13/26, P = NS) were comparable between SP and ML ECMO groups. Patients supported with ML had a trend toward higher hospital survival (1/7 vs. 12/26, P = 0.07) and significantly higher late survival (0/7 vs. 10/26, P = 0.05). The present experience shows that V- A ECMO for cardiac indications using centrifugal pumps in infants and children yields outcomes absolutely comparable to international registry ( ELSO) data using mostly roller pumps. Although changes in practice may have contributed to these results, use of ML centrifugal pumps appears to further improve end-organ recovery and hospital and late survival. [ABSTRACT FROM AUTHOR]

Poor survival has been demonstrated after ventricular assist device ( VAD) implantation for Interagency Registry for Mechanically Assisted Circulatory Support ( INTERMACS) profile 1 and 2 patients compared with more stable levels. However, risk factors within this high-risk cohort have not been determined so far. The aim of the present study was to identify risk factors associated with this very high mortality rate. Between February 1993 and January 2013, 298 patients underwent VAD implantation in our institution. One hundred nine patients were in INTERMACS level 1 and 49 patients were in INTERMACS level 2 and were therefore defined as hemodynamically critical (overall 158 patients). Assist devices implanted were: HVAD HeartWare n = 18; Incor n = 11; VentrAssist n = 2; DeBakey n = 22; and pulsatile systems n = 105. After cumulative support duration of 815.35 months, Kaplan- Meier analysis revealed a survival of 63.9, 48.8, and 40.3% at 1, 6, and 12 months, respectively. Cox regression analyses identified age > 50 ( P = 0.001, odds ratio [OR] 2.48), white blood cell count > 13.000/μL ( P = 0.01, OR 2.06), preoperative renal replacement therapy ( P = 0.001, OR 2.63), and postcardiotomy failure ( P < 0.001, OR 2.79) as independent predictors of mortality. Of note, last generation VADs were not associated with significantly better 6-month survival ( P = 0.59). Patients without the aforementioned risk factors could yield a survival of 79.2% at 6 months. This single-center experience shows that VAD implantation in hemodynamically unstable patients generally results in poor early outcome, even in third-generation pumps. However, avoiding the aforementioned risk factors could result in improved outcome. [ABSTRACT FROM AUTHOR]

The scarcity of donor organs has led to the development of devices that provide optimal long-term respiratory or cardiopulmonary support to bridge recipients as they wait for lung and/or heart transplantation. This study was designed to evaluate the 30-day in vivo performance of the newly developed pediatric pump-lung ( PediPL) for cardiopulmonary support using a juvenile sheep model. The PediPL device was placed surgically between the right atrium and descending aorta in eight sheep (25.4-31.2 kg) and evaluated for 30 days. Anticoagulation was maintained with continuous heparin infusion (activated clotting time 150-200 s). The flow rate was measured continually, and gas transfer was measured daily. Plasma free hemoglobin, platelet activation, hematologic data, and blood biochemistry were assessed twice a week. Sheep were euthanized after 30 days. The explanted devices were examined for gross thrombosis. Six sheep survived for 30-32 days. During the study, the oxygen transfer rate of the devices was 54.9 ± 13.2 mL/min at a mean flow rate of 1.14 ± 0.46 L/min with blood oxygen saturation of 95.4% ± 1.7%. Plasma free hemoglobin was 8.2 ± 3.7 mg/dL. Platelet activation was 5.35 ± 2.65%. The animals had normal organ chemistries except for surgery-related transient alterations in kidney and liver function. Although we found some scattered thrombi on the membrane surfaces of some explanted devices during the necropsy, the device function and performance did not degrade. The PediPL device was capable of providing cardiopulmonary support with long-term reliability and good biocompatibility over the 30-day duration and offers the potential option for bridging pediatric patients with end-stage heart or lung disease to heart and/or lung transplantation. [ABSTRACT FROM AUTHOR]