First experience with the new portable extracorporeal membrane oxygenation system Cardiohelp for severe respiratory failure in adults

Intensivist-Led Transportation of Patients on Extracorporeal Membrane Oxygenation: A Single Center Experience

This study evaluated the suitability, feasibility, safety, and outcomes of transport of the ECMO-dependent patient (EDP) by EDP transport team (EDPTT) in China. Eighty-two EDPs (forty-one cases on VV ECMO and forty-one cases on VA ECMO) received transport between June 2018 and June 2021 and were retrospectively analyzed. ECMO circulation was performed by the outlying hospital, mainly using percutaneous ECMO cannulation. The EDPTT consists of three intensive therapists, one of whom serves as a team leader, and one intensive care unit nurse. Of these, 81 (98.8%) patients were transferred by ambulance, no deaths occurred during transport, the EDP-related complications were 19% (n = 16); bleeding at the cannula site (n = 7, 8.5%) was the most prominent; equipment-related problems accounted for 14.6% of the problems requiring urgent intervention, with hand cranking being the most common (9.7%). The survival rate during transport was 100%, with 36 (43.9%) patients surviving to discharge. The ECMO weaning rate was 61% for VV ECMO and 63.7% for VA ECMO. The results demonstrated the suitability, feasibility, and safety of transporting EDP in a team led by an intensivist, with few complications and no deaths during transport. This may be the recommended staffing model for EDP transport in developing countries.

Single-Center Experience Using the Cardiohelp System for Neonatal and Pediatric Extracorporeal Membrane Oxygenation

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) systems have continued to evolve and improve with the development of smaller and portable systems. The Cardiohelp (Maquet Getinge Cardiopulmonary AG, Rastatt, Germany) portable life support device is a compact ECMO system used widely in adults and for ECMO transport. Reports of its use in neonatal and pediatric centers remain limited. In this single-center retrospective review, we describe our institutional experience with the Cardiohelp.

DESIGN

Single-center retrospective review.

SETTING

Neonatal ICUs and PICUs in a tertiary-care children's hospital.

PATIENTS

Seventeen pediatric patients on ECMO.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Median (interquartile range, IQR) of patient age was 0.5 years (0-7 yr). Eleven of 17 patients were on veno-arterial ECMO, five on veno-venous ECMO, and one on veno-venoarterial ECMO. All veno-venous and veno-venoarterial runs ( n = 6) were accomplished with bicaval, dual-lumen cannulae. Median duration on Cardiohelp was 113 hours (IQR 50-140 hr). Median anti-Xa level for patients was 0.43 IU/mL (IQR 0.35-0.47 IU/mL), with median heparin dose of 23.6 U/kg/hr (IQR 17.6-28.1 U/kg/hr). Median plasma-free hemoglobin was 41.4 mg/dL (IQR 30-60 mg/dL). Circuit change was required in three cases. Fourteen patients survived ECMO, with 13 patients surviving to discharge.

CONCLUSIONS

We have used the Cardiohelp system to support 17 neonatal and pediatric ECMO patients, without complications. Further studies are warranted to compare complications, outcomes, and overall cost with other institutions and other existing ECMO systems.

Research status and development trend of extracorporeal membrane oxygenation based on bibliometrics

Background

Using bibliometric method to analyze the research status and development trend of extracorporeal membrane oxygenation (ECMO), we aim to provide clinicians, scientists, and stakeholders with the most up-to-date and comprehensive overview of ECMO research.

Materials and methods

Using Excel and VOSviewer, the literature on ECMO was systematically analyzed regarding publication trends, journal source, foundation, countries, institutions, core authors, research hotspots, and market distribution.

Results

There were five important time nodes in the research process of ECMO, including the success of the first ECMO operation, the establishment of ELSO, and the outbreak of influenza A/H1N1 and COVID-19. The R&D centers of ECMO were the United States, Germany, Japan, and Italy, and the attention to ECMO was gradually increasing in China. The products most used in the literature were from Maquet, Medtronic, and LivaNova. Medicine enterprises attached great importance to the funding of ECMO research. In recent years, the literature has mainly focused on the following aspects: the treatment of ARDS, the prevention of coagulation system-related complications, the application in neonatal and pediatric patients, mechanical circulatory support for cardiogenic shock, and ECPR and ECMO during the COVID-19 pandemic.

Conclusion

The frequent epidemic occurrence of viral pneumonia and the technical advancement of ECMO in recent years have caused an increase in clinical applications. The hot spots of ECMO research are shown in the treatment of ARDS, mechanical circulatory support for cardiogenic shock, and the application during the COVID-19 pandemic.

Membrane Lung and Blood Pump Use During Prolonged Extracorporeal Membrane Oxygenation: Trends From 2002 to 2017

Extracorporeal life support (ECLS) has grown in its application since its first clinical description in the 1970s. The technology has been used to support a wide variety of mechanical support modalities and diseases, including respiratory failure, cardiorespiratory failure, and cardiac failure. Over many decades and safety and efficacy studies, followed by randomized clinical trials and thousands of clinical uses, ECLS is considered as an accepted treatment option for severe pulmonary and selected cardiovascular failure. Extracorporeal life support involves the use of support artificial organs, including a membrane lung and blood pump. Over time, changes in the technology and the management of ECLS support devices have evolved. This manuscript describes the use of membrane lungs and blood pumps used during ECLS support from 2002 to 2017 in over 65,000 patients reported to the Extracorporeal Life Support Organization Registry. Device longevity and complications associated with membrane lungs and blood pump are described and stratified by age group: neonates, pediatrics, and adults.

Cardiohelp System use in school age children and adolescents at a center with interfacility mobile extracorporeal membrane oxygenation capability

Cardiohelp System use for pediatric extracorporeal membrane oxygenation (ECMO) beyond the transport setting is sparsely described in literature. We report the use of Getinge's Cardiohelp System in children and integrated utilization of Mobile ECMO Retrieval Team (MERT) at an all-age specialized cardiorespiratory center. Electronic database of all patients under 16 years of age who received ECMO with use of the Cardiohelp System between January 2018 and March 2020 was retrospectively reviewed and analyzed for demographics, set-up, complications, and outcomes. Out of 41 patients, seven patients (four in middle childhood, three in early teenage) with median age of 10 years (range 8.8-15.6) were supported with use of Cardiohelp System. Median weight and height were 34 kg (range 28-53) and 145 cm (range 134-166) respectively. Initial ECMO deployment was veno-arterial (V-A) in five patients and veno-venous (V-V) in two. There were three interhospital transfers by our MERT, and 12 intrahospital transfers for interventions or imaging. The median ECMO therapy was 7 days (range 4-25), with standard 3/8-inch tubing and ECMO flow rate range at 56-100 mL/kg/min (1.89-5.0 LPM). There were two circuit changes and three reconfigurations of support. Two patients received continuous veno-venous hemofiltration via ECMO circuit. The 90-day and 180-day survival rates were 100% (including two heart transplants at day 7 and day 8). There were no transport-related or circuit-related complications during the 1750 h of Cardiohelp use. Cardiohelp System use is safe in pediatric patients for diverse application of ECMO support including inter- and intrahospital transfers.

Air Medical Transport of Patients Diagnosed With Confirmed Coronavirus Disease 2019 Infection Undergoing Extracorporeal Membrane Oxygenation: A Case Review and Lessons Learned

The coronavirus disease 2019 pandemic disrupted health care delivery in every respect, including critical care resources and the transport of patients requiring extracorporeal membrane oxygenation. Innovative solutions allowing for safe helicopter air transport of these critical patients is needed because extracorporeal membrane oxygenation resources are only available in specialty centers. We present a case demonstrating the interfacility collaboration of care for a patient with coronavirus disease 2019 infection and the lessons learned from the air transport. Careful planning, coordination, communication, and teamwork contributed to the safe transport of this patient and several others subsequently.

Evaluation of effect of scheduled fresh frozen plasma on ECMO circuit life: A randomized pilot trial

BACKGROUND

Factor consumption is common during ECMO complicating the balance of pro and anticoagulation factors. This study sought to determine whether transfusion of coagulation factors using fresh frozen plasma (FFP) increased ECMO circuit life and decreased blood product transfusion. Secondly, it analyzed the association between FFP transfusion and hemorrhagic and thrombotic complications.

STUDY DESIGN AND METHODS

Thirty-one pediatric ECMO patients between October 2013 and January 2016 at a quaternary care institution were included. Patients were randomized to FFP every 48 hours or usual care. The primary outcome was ECMO circuit change. Secondary outcomes included blood product transfusion, survival to decannulation, hemorrhagic and thrombotic complications, and ECMO costs.

RESULTS

Median (interquartile range [IQR]) number of circuit changes was 0 (0, 1). No difference was seen in percent days without a circuit change between intervention and control group, P = .53. Intervention group patients received median platelets of 15.5 mL/kg/d IQR (3.7, 26.8) vs 24.8 mL/kg/d (12.2, 30.8) for the control group (P = .16), and median packed red blood cells (pRBC) of 7.7 mL/kg/d (3.3, 16.3) vs 5.9 mL/kg/d (3.4, 18.7) for the control group, P = .60. FFP transfusions were similar with 10.2 mL/kg/d (5.0, 13.9) in the intervention group vs 8.8 (2.5, 17.7) for the control group, P = .98.

CONCLUSION

In this pilot randomized study, scheduled FFP did not increase circuit life. There was no difference in blood product transfusion of platelets, pRBCs, and FFP between groups. Further studies are needed to examine the association of scheduled FFP with blood product transfusion.

In Vivo 5 Day Animal Studies of a Compact, Wearable Pumping Artificial Lung

Recent studies show improved outcomes in ambulated lung failure patients. Ambulation still remains a challenge in these patients. This necessitates development of more compact and less cumbersome respiratory support specifically designed to be wearable. The Paracorporeal Ambulatory Assist Lung (PAAL) is being designed for providing ambulatory support in lung failure patients during bridge to transplant or recovery. We previously published in vitro and acute in vivo results of the PAAL. This study further evaluates the PAAL for 5 days. Five-day in vivo studies with the PAAL were conducted in 50-60 kg sheep after heparinization (activated clotting time range: 190-250 s) and cannulation with a 27 Fr. Avalon Elite dual-lumen cannula. The animals were able to move freely in a stanchion while device flow, resistance, and hemodynamics were recorded hourly. Oxygenation and hemolysis were measured daily. Platelet activation, blood chemistry, and comprehensive blood counts are reported for preoperatively, on POD 0, and POD 5. Three animals survived for 5 days. No study termination resulted from device failure. One animal was terminated on POD 0 and one animal was terminated at POD 3. The device was operated between 1.93 and 2.15 L/min. Blood left the device 100% oxygenated. Plasma-free hemoglobin ranged 10.8-14.5 mg/dl. CD62-P expression was under 10%. Minimal thrombus was seen in devices at explant. Chronic use of the PAAL in awake sheep is promising based on our study. There were no device-related complications over the study course. This study represents the next step in our pathway to eventual clinical translation.

ECMO without anticoagulation in patients with disease-related severe thrombocytopenia: Feasible but futile?

Severe thrombocytopenia poses a high risk for bleeding thus representing a relative contraindication for anticoagulation and therefore extracorporeal membrane oxygenation (ECMO). We herein report on a series of immunocompromised patients with severe thrombocytopenia undergoing long-term ECMO without systemic anticoagulation. We retrospectively identified seven adult patients with anticoagulation withdrawal for ≥3 days (range 5-317) during venovenous ECMO therapy due to thrombocytopenia < 50 G/L treated in a university-affiliated hospital from January 2013 to April 2017. All ECMO systems used were heparin coated. Overall, 530 ECMO days were observed, 404 (76%) of them without systemic anticoagulation. Platelet count during ECMO treatment was 24 G/L (median, range 1-138), ECMO duration was 35 days (5-317), and ECMO was run without any anticoagulation for 20 days (5-317). Altogether, five clotting events were seen leading to oxygenator exchanges. Bleeding was common including one fatal intracerebral hemorrhage. Altogether, 29 platelet concentrates per patient (7-207) were administered, which correspond to 0.8 per day (0.6-1.3). One patient survived ICU and hospital. In patients with thrombocytopenia, ECMO can be run without anticoagulation even for considerably long periods of time. Bleeding remains common, while clotting events seem to be rare. However, prognosis of this patient population undergoing ECMO support seems grim.

Impact of cannula design on packed red blood cell transfusions: technical advancement to improve outcomes in extracorporeal membrane oxygenation

Background

Technological improvement has contributed to making veno-venous extracorporeal membrane oxygenation (VV-ECMO) safer and easier, spreading its use in acute respiratory failure (ARF).

Methods

This is a retrospective observational study carried out in the ECMO center at IRCCS-ISMETT, a medical center focused on end-stage organ failure treatment in Italy. We investigated the effect of different cannula designs on the amount of blood product transfused. Eighty-nine consecutive patients affected with ARF on VV-ECMO from 2008 to 2016 were compared according to type of cannulation: older percutaneous cannula (Standard group, 52 patients) and HLS^© BIOLINE-coated, but with shorter drainage cannula (BIOLINE group, 37 patients).

Results

The two study groups were comparable in terms of baseline characteristics [age, body mass index (BMI), Simplified Acute Physiology Score (SAPS-II), Sequential Organ Failure Assessment (SOFA), Predicting Death For Severe ARDS on VV-ECMO (PRESERVE) score] and ECMO management [median hematocrit (Htc), platelet nadir, antithrombin III (AT III), heparin, activated partial thromboplastin time (APTT)]. In the BIOLINE group, a lower amount of packed red blood cells (pRBC) was transfused considering both total number [4 units, interquartile range (IQR) 1-9 vs. 12 units, IQR 5.5-21; P<0.01] and mL of pRBC/day of ECMO support (91, IQR 21-158 vs. 193.5, IQR 140.5-254; P<0.01). In the BIOLINE group, a trend in reduction of ECMO days (P=0.05) and length of intensive care unit (ICU) stay was found (P=0.06), but no differences in rates of ECMO weaning and ICU discharge were evidenced. The BIOLINE group constituted a saving of €1,295.20 per patient/treatment, counting the costs for cannulation and pRBC administration.

Conclusions

More biocompatible and shorter drainage cannula may represent one of the contributing factors to a reduction in transfusions and costs of VV-ECMO in the current ongoing technological improvement in ECMO.

Fiber Bundle Design for an Integrated Wearable Artificial Lung

Mechanical ventilation (MV) and extracorporeal membrane oxygenation (ECMO) are the only viable treatment options for lung failure patients at the end-stage, including acute respiratory distress syndrome (ARDS) and chronic obstructive pulmonary disease (COPD). These treatments, however, are associated with high morbidity and mortality because of long wait times for lung transplant. Contemporary clinical literature has shown ambulation improves post-transplant outcomes in lung failure patients. Given this, we are developing the Pittsburgh Ambulatory Assist Lung (PAAL), a truly wearable artificial lung that allows for ambulation. In this study, we targeted 180 ml/min oxygenation and determined the form factor for a hollow fiber membrane (HFM) bundle for the PAAL. Based on a previously published mass transfer correlation, we modeled oxygenation efficiency as a function of fiber bundle diameter. Three benchmark fiber bundles were fabricated to validate the model through in vitro blood gas exchange at blood flow rates from 1 to 4 L/min according to ASTM standards. We used the model to determine a final design, which was characterized in vitro through a gas exchange as well as a hemolysis study at 3.5 L/min. The percent difference between model predictions and experiment for the benchmark bundles ranged from 3% to 17.5% at the flow rates tested. Using the model, we predicted a 1.75 in diameter bundle with 0.65 m surface area would produce 180 ml/min at 3.5 L/min blood flow rate. The oxygenation efficiency was 278 ml/min/m and the Normalized Index of Hemolysis (NIH) was less than 0.05 g/100 L. Future work involves integrating this bundle into the PAAL for which an experimental prototype is under development in our laboratory.

Recent advances in extracorporeal life support as a bridge to lung transplantation

INTRODUCTION

Invasive mechanical respiratory support in candidate bridging to transplant (BTT) has become common practice in recent years. This usually consists of mechanical ventilation, extracorporeal life support (ECLS) or a combination of both techniques. Areas covered: This review covers epidemiology, technical considerations, indications and outcome of ELCS as BTT. Published literature was identified by searching the MEDLINE bibliographic database (1946-present) and appropriate papers were reviewed. In a retrospective analysis of the period 2010-2016 (n = 92 cases of ECLS bridging, 62% ECLS only) at our institution, bridging success was 73%, with 1-year survival among patients surviving to transplant 78%, surpassing our previously published results between 2005-2009 (bridging success 58%, 1-year survival 58%, p = 0.002 and p = 0.02, respectively). Expert commentary: While ECLS success has influenced lung transplant selection criteria, bridging remains technically and ethically challenging. Candidate selection and organ allocation are crucial to achieving acceptable results.

Retrieval of Adult Patients on Extracorporeal Membrane Oxygenation by an Intensive Care Physician Model

The optimal staffing model during the inter-hospital transfer of patients on extracorporeal membrane oxygenation (ECMO) is not known. We report the complications and outcomes of patients who were commenced on ECMO at a referring hospital by intensive care physicians and compare these findings with patients who had ECMO established at an ECMO center in Australia. This was a single center, retrospective observational study based on a prospectively collected ECMO database from Melbourne, Australia. Patients with severe cardiac and/or respiratory failure failing conventional supportive treatment between 2007-2013 were placed on ECMO via a physician-led model of ECMO retrieval, including two intensivists in a four person team, using percutaneous ECMO cannulation. Patients (198) underwent ECMO over the study period, of which 31% were retrieved. Veno-venous (VV)-ECMO and veno-arterial (VA)-ECMO accounted for 27 and 73% respectively. The VA-ECMO patients had more intra-transport interventions compared with VV-ECMO transported patients, but none resulting in serious morbidity or death. There was no overall difference in survival at 6 months between retrieved and ECMO center patients: VV-ECMO (75 vs. 70%, P = 0.690) versus VA-ECMO (70 vs. 68%, P = 1.000). An intensive care physician-led team was able to safely place all critically ill patients on ECMO and retrieve them to an ECMO center. This may be an appropriate staffing model for ECMO retrieval.

Principi e indicazioni dell’assistenza circolatoria e respiratoria extracorporea in chirurgia toracica

In origine, l’extracorporeal membrane oxygenation (ECMO) era una tecnica di assistenza respiratoria che utilizzava uno scambiatore gassoso a membrana. Per estensione, l’ECMO è diventata una tecnica respiratoria e cardiopolmonare utilizzata in caso di deficit respiratorio e/o cardiaco nell’attesa della restaurazione della funzione deficitaria o di un eventuale trapianto. Il supporto emodinamico può essere parziale o totale. Gli accessi vascolari possono essere periferici o centrali. Questo tipo di assistenza utilizza il concetto di circolazione extracorporea (CEC) sanguigna che in epoca moderna si è estesa con l’utilizzo di polmoni artificiali a membrana. Il circuito di base è semplice e comprende una pompa, un ossigenatore (che permette al sangue di caricarsi di O₂ e di eliminare CO₂) e delle vie d’accesso (una di drenaggio e una di reinfusione). La sua attuazione è facile, veloce e può essere avviata al letto del malato. Il miglioramento delle attrezzature, una migliore conoscenza delle tecniche e delle indicazioni, e le politiche di salute pubblica hanno reso popolare questa tecnica. Alcuni centri di chirurgia toracica la utilizzano di routine come assistenza alla realizzazione di un intervento terapeutico (soprattutto trapianto) assieme a team di rianimazione per il trattamento della sindrome da distress respiratorio acuto. Nel quadro della malattia polmonare dell’adulto, l’idea principale è quella di sviluppare il concetto di strategia minimalista con l’uso di una CEC adiuvante parziale – più che sostitutiva totale – che permetterebbe il recupero metabolico ad integrum del paziente. Nei prossimi anni, i progressi della tecnologia e dell’ingegneria così come le conoscenze approfondite permetteranno il miglioramento della prognosi dei pazienti colpiti da deficit respiratorio sotto assistenza meccanica.

Impact of dynamic changes of elevated bilirubin on survival in patients on veno-arterial extracorporeal life support for acute circulatory failure

Aims

Veno-arterial extracorporeal life support (ECLS) is an established method to stabilize acute circulatory failure. Parameters and data on when to ideally wean circulatory support are limited. Bilirubin is a marker of end-organ damage. Therefore, the purpose of this large study was to evaluate the impact of dynamic changes of elevated bilirubin levels on survival in patients on ECLS.

Methods and results

We reviewed 502 consecutive cases of ECLS from 2007 to 2015. Bilirubin levels were recorded before implantation and until six days after explantation. Dynamic bilirubin changes, and hemodynamic and laboratory outcome parameters were compared in survivors and nonsurvivors. Reason for ECLS implantation was cardiac arrest with ongoing resuscitation in 230 (45.8%), low cardiac output in 174 (34.7%) and inability to wean off cardiopulmonary bypass in 98 (19.5%) patients. 307 (61.2%) patients were weaned off ECLS, however, 206 (41.0%) survived. Mean duration of ECLS was 3 (2–6) days, and survivors received significantly longer ECLS (5 vs 3 days, p < 0.001). Survivors had significantly lower baseline bilirubin levels (p = 0.003). Bilirubin started to rise from day 2 in all patients. In survivors, bilirubin levels had trended down on the day of ECLS explantation and stayed at an acceptable level. However, in weaned patients who did not survive and patients who died on ECLS bilirubin levels continued to rise during the recorded period.

Conclusion

ECLS support improves survival in patients with acute circulatory failure. Down trending bilirubin levels on veno-arterial ECLS indicate improved chances of successful weaning and survival in hemodynamically stable patients.

Darcy Permeability of Hollow Fiber Membrane Bundles Made from Membrana Polymethylpentene Fibers Used in Respiratory Assist Devices

Hollow fiber membranes (HFMs) are used in blood oxygenators for cardiopulmonary bypass or in next generation artificial lungs. Flow analyses of these devices is typically done using computational fluid dynamics (CFD) modeling HFM bundles as porous media, using a Darcy permeability coefficient estimated from the Blake-Kozeny (BK) equation to account for viscous drag from fibers. We recently published how well this approach can predict Darcy permeability for fiber bundles made from polypropylene HFMs, showing the prediction can be significantly improved using an experimentally derived correlation between the BK constant (A) and bundle porosity (ε). In this study, we assessed how well our correlation for A worked for predicting the Darcy permeability of fiber bundles made from Membrana polymethylpentene (PMP) HFMs, which are increasingly being used clinically. Swatches in the porosity range of 0.4 to 0.8 were assessed in which sheets of fiber were stacked in parallel, perpendicular, and angled configurations. Our previously published correlation predicted Darcy within ±8%. A new correlation based on current and past measured permeability was determined: A = 497ε - 103; using this correlation measured Darcy permeability was within ±6%. This correlation varied from 8% to -3.5% of our prior correlation over the tested porosity range.

[Extracorporeal life support in thoracic surgery: What are the indications and the pertinence?]

INTRODUCTION

In thoracic surgery, extracorporeal life support (ECLS) technologies are used in cases of severe and refractory respiratory failure or as intraoperative cardiorespiratory support. The objectives of this review are to describe the rationale of ECLS techniques, to review the pulmonary diseases potentially treated by ECLS, and finally to demonstrate the efficacy of ECLS, using recently published data from the literature, in order to practice evidence based medicine.

STATE OF THE ART

ECLS technologies should only be undertaken in expert centers. ECLS allows a protective ventilatory strategy in severe ARDS. In the field of lung transplantation, ECLS may be used successfully as a bridge to transplantation, as intraoperative cardiorespiratory support or as a bridge to recovery in cases of severe primary graft dysfunction. In general thoracic surgery, ECLS technology seems to be safe and efficient as intraoperative respiratory support for tracheobronchial surgery or for severe respiratory insufficiency, without significant increase in perioperative risk.

PERSPECTIVE

The indications for ECLS are going to increase. Future improvements both in scientific knowledge and bioengineering will improve the prognosis of patients treated with ECLS for respiratory failure. Multicenter randomized controlled trials will refine the indications for ECLS and improve the global care strategies for these patients.

CONCLUSION

ECLS is an efficient therapeutic strategy that will improve the prognosis of patients suffering from, or exposed to, the risks of severe respiratory failure.

The ICM research agenda on extracorporeal life support

PURPOSE

This study aimed to concisely describe the current standards of care, major recent advances, common beliefs that have been contradicted by recent trials, areas of uncertainty, and clinical studies that need to be performed over the next decade and their expected outcomes with regard to extracorporeal membrane oxygenation (ECMO).

METHODS

Narrative review based on a systematic analysis of the medical literature, national and international guidelines, and expert opinion.

RESULTS

The use of venovenous ECMO (VV-ECMO) is increasing in the most severe forms of acute lung injury. In patients with cardiogenic shock, short-term veno-arterial ECMO (VA-ECMO) provides both pulmonary and circulatory support. Technological improvements and recently published studies suggest that ECMO is able to improve patients' outcomes. There are, however, many uncertainties regarding the real benefits of this technique both in hemodynamic and respiratory failure, the territorial organization to deliver ECMO, the indications and the use of concomitant treatments.

CONCLUSIONS

Although there have been considerable advances regarding the use of ECMO in critically ill patients, the risk/benefit ratio remains underinvestigated. ECMO indications, organization of ECMO delivery, and use of adjuvant therapeutics need also to be explored. Ongoing and future studies may be able to resolve these issues.

Extracorporeal membrane oxygenation (ECMO) as a treatment strategy for severe acute respiratory distress syndrome (ARDS) in the low tidal volume era: A systematic review

OBJECTIVE

To evaluate the hospital survival in patients with severe ARDS managed with ECMO and low tidal volume ventilation as compared to patients managed with low tidal volume ventilation alone.

METHODS

Electronic databases were searched for studies of at least 10 adult patients with severe ARDS comparing the use of ECMO with low tidal volume ventilation to mechanical ventilation with a low tidal volume alone. Only studies reporting hospital or ICU survival were included. All identified studies were assessed independently by two reviewers.

RESULTS

Of 1782 citations, 27 studies (n=1674) met inclusion criteria. Hospital survival for ECMO patients ranged from 33.3 to 86%, while survival with conventional therapy ranged from 36.3 to 71.2%. Five studies were identified with appropriate control groups allowing comparison, but due to the high degree of variability between studies (I²=63%), their results could not be pooled. Two of these studies demonstrated a significant difference, both favouring ECMO over conventional therapy.

CONCLUSION

Given the lack of studies with appropriate control groups, our confidence in a difference in outcome between the two therapies remains weak. Future studies on the use of ECMO for severe ARDS are needed to clarify the role of ECMO in this disease.

Extracorporeal membrane oxygenation for acute respiratory distress syndrome in adults: an analysis of differences between survivors and non-survivors

OBJECTIVES

Over the last decade, extracorporeal membrane oxygenation (ECMO) has become a promising option for patients with severe acute respiratory distress syndrome (ARDS). In this single-center observational cohort study, data from a patient group with severe ARDS treated with ECMO was analyzed.

METHODS

Data from 46 patients [median age 54 years (18 to 72), male: 65.2%] were evaluated retrospectively between January 2009 and September 2015.

RESULTS

Diagnosis leading to ARDS was pneumonia in 63.1% of the patients. The median SOFA Score was 13 (10 to 19) and the median LIS was 3.5 (2.67 to 4). The median duration of ECMO support was 12 days (1 to 86). Twenty-eight patients (60.9%) were successfully weaned from ECMO and 22 patients survived (47.8%). Non-survivors needed significantly more frequent renal replacement therapy (37.5% vs. 18.2%; p<0.01) and transfusion of red blood cell concentrates [0.4 units (0.3 to 1.2) vs. 0.9 units (0.5 to 1.6); p<0.01] during ECMO support compared to patients who survived.

CONCLUSION

This report suggests that ECMO currently allows treatment of severe ARDS with presumed improved survival. The incidence rate of acute kidney injury and transfusion are associated with adverse outcomes.

In vitro and in vivo evaluation of a novel integrated wearable artificial lung

BACKGROUND

Conventional extracorporeal membrane oxygenation (ECMO) is cumbersome and is associated with high morbidity and mortality. We are currently developing the Pittsburgh Ambulatory Assist Lung (PAAL), which is designed to allow for ambulation of lung failure patients during bridge to transplant or recovery. In this study, we investigated the in vitro and acute in vivo performance of the PAAL.

METHODS

The PAAL features a 1.75-inch-diameter, cylindrical, hollow-fiber membrane (HFM) bundle of stacked sheets, with a surface area of 0.65 m² integrated with a centrifugal pump. The PAAL was tested on the bench for hydrodynamic performance, gas exchange and hemolysis. It was then tested in 40- to 60-kg adult sheep (n = 4) for 6 hours. The animals were cannulated with an Avalon Elite 27Fr dual-lumen catheter (DLC) inserted through the right external jugular into the superior vena cava (SVC), right atrium (RA) and inferior vena cava (IVC).

RESULTS

The PAAL pumped >250 mm Hg at 3.5 liters/min at a rotation speed of 2,100 rpm. Oxygenation performance met the target of 180 ml/min at 3.5 liters/min of blood flow in vitro, resulting in a gas-exchange efficiency of 278 ml/min/m². The normalized index of hemolysis (NIH) for the PAAL and cannula was 0.054 g per 100 liters (n = 2) at 3.5 liters/min, as compared with 0.020 g per 100 liters (n = 2) for controls (DLC cannula and a Centrimag pump). Plasma-free hemoglobin (pfHb) was <20 mg/dl for all animals. Blood left the device 100% oxygenated in vivo and oxygenation reached 181 ml/min at 3.8 liters/min.

CONCLUSION

The PAAL met in vitro and acute in vivo performance targets. Five-day chronic sheep studies are planned for the near future.

Transportation of patients on extracorporeal membrane oxygenation: a tertiary medical center experience and systematic review of the literature

Background

Utilization of extracorporeal membrane oxygenation (ECMO) has increased worldwide, but its use remains restricted to severely ill patients, and few referral centers are properly structured to offer this support. Inter-hospital transfer of patients on ECMO support can be life-threatening. In this study, we report a single-center experience and a systematic review of the available published data on complications and mortality associated with ECMO transportation.

Methods

We reported single-center data regarding complications and mortality associated with the transportation of patients on ECMO support. Additionally, we searched multiple databases for case series, observational studies, and randomized controlled trials regarding mortality of patients transferred on ECMO support. Results were analyzed independently for pediatric (under 12 years old) and adult populations. We pooled mortality rates using a random-effects model. Complications and transportation data were also described.

Results

A total of 38 manuscripts, including our series, were included in the final analysis, totaling 1481 patients transported on ECMO support. A total of 951 patients survived to hospital discharge. The pooled survival rates for adult and pediatric patients were 62% (95% CI 57–68) and 68% (95% CI 60–75), respectively. Two deaths occurred during patient transportation. No other complication resulting in adverse outcome was reported.

Conclusion

Using the available pooled data, we found that patient transfer to a referral institution while on ECMO support seems to be safe and adds no significant risk of mortality to ECMO patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-016-0232-7) contains supplementary material, which is available to authorized users.

Development of a new interfacility extracorporeal membrane oxygenation transport program for pediatric lung transplantation evaluation

Pediatric lung transplantation is a life-saving intervention for children with irreversible end-stage lung disease. Access to transplant can be limited by geographic isolation from a center or the presence of comorbidities affecting transplant eligibility. Extracorporeal membrane oxygenation (ECMO)-supported patients are an uncommon but historically high-risk cohort of patients considered for lung transplant. We report the development of a service at our center to provide transport services to our hospital for patients unable to wean from ECMO support at their local institution for the purpose of evaluation for lung transplantation by our program. We developed a process for pre-transport consultation by the lung transplant physician team, standardized hand-off tools and equipment lists, and procedures for transitioning patients to transport ECMO machinery. Four patients have been transported to date including fixed wing (FW) and helicopter transports. All patients were successfully transported with either none or minor complications. Transport of ECMO-supported patients is a feasible method to increase access of patients with irreversible lung injured patients to evaluation for lung transplant.

Remote cannulation and extracorporeal membrane oxygenation transport is safe in a newly established program

Extracorporeal membrane oxygenation (ECMO) has become an increasingly utilized modality for the support of patients with severe cardiac or pulmonary dysfunction. Unfortunately, the costs and expertise required to maintain a formal ECMO program preclude the vast majority of hospitals from employing such technology routinely. These barriers to implementation of an effective ECMO program highlight the importance of the safe transport of patients in need of extracorporeal support. While many centers with extensive expertise in the management of patients on extracorporeal support have demonstrated their ability to transport those same patients, the ability of new ECMO programs to provide such transportation remains poorly studied. We established an ECMO program at our institution and immediately provided equipment and personnel to transport patients in need of or receiving extracorporeal support to our institution. Overall, we found that 13 out of 28 patients transported to our institution on ECMO or for consideration of ECMO support during the first 15 months of the program survived to hospital discharge. During that period, four incidents associated with patient transport occurred but none were related to ECMO support or adversely affected patient outcome. These observations demonstrate that new ECMO programs can safely and reliably transport patients on or in need of extracorporeal support.

[Artificial organs]

Research has been fighting against organ failure and shortage of donations by supplying artificial organs for many years. With the raise of new technologies, tissue engineering and regenerative medicine, many organs can benefit of an artificial equivalent: thanks to retinal implants some blind people can visualize stimuli, an artificial heart can be proposed in case of cardiac failure while awaiting for a heart transplant, artificial larynx enables laryngectomy patients to an almost normal life, while the diabetic can get a glycemic self-regulation controlled by smartphones with an artificial device. Dialysis devices become portable, as well as the oxygenation systems for terminal respiratory failure. Bright prospects are being explored or might emerge in a near future. However, the retrospective assessment of putative side effects is not yet sufficient. Finally, the cost of these new devices is significant even if the advent of three dimensional printers may reduce it.

Principi e indicazioni dell’assistenza circolatoria e respiratoria extracorporea in chirurgia toracica

In origine, l’extracorporeal membrane oxygenation (ECMO) era una tecnica di assistenza respiratoria che utilizzava uno scambiatore gassoso a membrana. Per estensione, l’ECMO è diventata una tecnica respiratoria e cardiopolmonare utilizzata in caso di deficit respiratorio e/o cardiaco nell’attesa della restaurazione della funzione deficitaria o di un eventuale trapianto. Il supporto emodinamico può essere parziale o totale. Gli accessi vascolari possono essere periferici o centrali. Questo tipo di assistenza utilizza il concetto di circolazione extracorporea (CEC) sanguigna che in epoca moderna si è estesa con l’utilizzo di polmoni artificiali a membrana. Il circuito di base è semplice e comprende una pompa, un ossigenatore (che permette al sangue di caricarsi di O₂ e di eliminare CO₂) e delle vie d’accesso (una di drenaggio e una di reinfusione). La sua attuazione è facile, veloce e può essere avviata al letto del malato. Il miglioramento delle attrezzature, una migliore conoscenza delle tecniche e delle indicazioni, e le politiche di salute pubblica hanno reso popolare questa tecnica. Alcuni centri di chirurgia toracica la utilizzano di routine come assistenza alla realizzazione di un intervento terapeutico (soprattutto trapianto) assieme a team di rianimazione per il trattamento della sindrome da distress respiratorio acuto. Nel quadro della malattia polmonare dell’adulto, l’idea principale è quella di sviluppare il concetto di strategia minimalista con l’uso di una CEC adiuvante parziale – più che sostitutiva totale – che permetterebbe il recupero metabolico ad integrum del paziente. Nei prossimi anni, i progressi della tecnologia e dell’ingegneria così come le conoscenze approfondite permetteranno il miglioramento della prognosi dei pazienti colpiti da deficit respiratorio sotto assistenza meccanica.

Venovenous Extracorporeal Membrane Oxygenation in Intractable Pulmonary Insufficiency: Practical Issues and Future Directions

Venovenous extracorporeal membrane oxygenation (vv-ECMO) is a highly invasive method for organ support that is gaining in popularity due to recent technical advances and its successful application in the recent H1N1 epidemic. Although running a vv-ECMO program is potentially feasible for many hospitals, there are many theoretical concepts and practical issues that merit attention and require expertise. In this review, we focus on indications for vv-ECMO, components of the circuit, and management of patients on vv-ECMO. Concepts regarding oxygenation and decarboxylation and how they can be influenced are discussed. Day-to-day management, weaning, and most frequent complications are covered in light of the recent literature.

Impact of Acute Kidney Injury on Outcome in Patients With Severe Acute Respiratory Failure Receiving Extracorporeal Membrane Oxygenation

OBJECTIVES

Extracorporeal lung support is currently used in the treatment of patients with severe respiratory failure until organ recovery and as a bridge to further therapeutic modalities. The aim of our study was to evaluate the impact of acute kidney injury on outcome in patients with acute respiratory distress syndrome under venovenous extracorporeal membrane oxygenation support and to analyze the association between prognosis and the time of occurrence of acute kidney injury and renal replacement therapy initiation.

DESIGN

Retrospective observational study.

SETTING

A large European extracorporeal membrane oxygenation center, University Medical Center Regensburg, Germany.

PATIENTS

A total of 262 consecutive adult patients with acute respiratory distress syndrome have been treated with extracorporeal membrane oxygenation between January 2007 and May 2012.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

Patient median age was 49 years (range, 18-78 yr); 183 (69.8%) were male. The leading cause of lung failure was pneumonia. The median Sequential Organ Failure Assessment score was 12.0 (8.8-15.0), and the median lung injury score was 3.3 (3.3-3.7). The median extracorporeal membrane oxygenation support duration was 9 days (6-15 d). One hundred eighty-three patients (69.8%) were successfully weaned and 156 patients (59.9%) survived to hospital discharge. One hundred thirty-one patients (50.0%) were treated with renal replacement therapy during extracorporeal membrane oxygenation support. The survival rate was significantly lower in patients requiring renal replacement therapy compared with those without renal replacement therapy (47.3% vs 71.8%; p < 0.001) overall. The Kaplan-Meier survival curves differed significantly for patients without renal replacement therapy versus patients with renal replacement therapy prior to extracorporeal membrane oxygenation support (p = 0.003). Furthermore, the multivariate logistic regression analysis suggests that the necessity of renal replacement therapy prior to extracorporeal membrane oxygenation insertion was an independent risk factor for mortality (95% CI, 0.77-0.88; p < 0.001). However, the necessity of renal replacement therapy during extracorporeal membrane oxygenation support was not an independent risk factor for mortality in these patients (p = 0.37).

CONCLUSIONS

Acute kidney injury is a major complication in acute respiratory distress syndrome probably mirroring severe systemic disease. In our cohort, development of acute kidney injury requiring renal replacement therapy prior to extracorporeal membrane oxygenation insertion was negatively associated with survival, whereas acute kidney injury that developed during extracorporeal membrane oxygenation support was not.

Extracorporeal life support for severe acute respiratory distress syndrome

PURPOSE OF REVIEW

To provide a summary of the recent literature on extracorporeal membrane oxygenation (ECMO) in adults with severe acute respiratory distress syndrome (ARDS), focusing on advances in equipment, current conventional and unconventional indications, complications, and future applications.

RECENT FINDINGS

ECMO use has increased during the past 5 years. Advances in cannulation, circuit design, and patient selection have made it a safer therapeutic option in severe ARDS, and its use has become more widespread for nonconventional indications.

SUMMARY

High-quality evidence for the routine use of ECMO for management of adult patients with severe ARDS is still lacking. An ongoing randomized controlled trial (ECMO to rescue lung injury in severe ARDS) will contribute valuable data to guide clinical decisions to opt for this supportive therapy.

Extracorporeal gas exchange for acute respiratory failure in adult patients: a systematic review

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2015 and co-published as a series in Critical Care. Other articles in the series can be found online at http://ccforum.com/series/annualupdate2015. Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901.

Mechanical ventilation during extracorporeal life support (ECLS): a systematic review

PURPOSE

In patients with acute respiratory distress syndrome (ARDS), extracorporeal life support (ECLS) has been utilized to support gas exchange and mitigate ventilator-induced lung injury (VILI). The optimal ventilation settings while on ECLS are unknown. The purpose of this systematic review is to describe the ventilation practices in patients with ARDS who require ECLS.

METHODS

We electronically searched MEDLINE, EMBASE, CENTRAL, AMED, and HAPI (inception to January 2015). Studies included were randomized controlled trials, observational studies, or case series (≥4 patients) of ARDS patients undergoing ECLS. Our review focused on studies describing ventilation practices employed during ECLS for ARDS.

RESULTS

Forty-nine studies (2,042 patients) met our inclusion criteria. Prior to initiation of ECLS, at least one parameter consistent with injurious ventilation [tidal volume >8 mL/kg predicted body weight (PBW), peak pressure >35 cmH2O (or plateau pressure >30 cmH2O), or FiO2 ≥0.8] was noted in 90% of studies. After initiation of ECLS, studies reported median [interquartile range (IQR)] reductions in: tidal volume [2.4 mL/kg PBW (2.2-2.9)], plateau pressure [4.3 cmH2O (3.5-5.8)], positive end-expiratory pressure (PEEP) [0.20 cmH2O (0-3.0)], and FiO2 [0.40 (0.30-0.60)]. Median (IQR) overall mortality was 41 % (31-51%).

CONCLUSIONS

Reduction in the intensity of mechanical ventilation in patients with ARDS supported by ECLS is common, suggesting that clinicians may be focused on reducing VILI after ECLS initiation. Future investigations should focus on establishing the optimal ventilatory strategy for patients with ARDS who require ECLS.

Bridge to lung transplantation and rescue post-transplant: the expanding role of extracorporeal membrane oxygenation

Over the last several decades, the growth of lung transplantation has been hindered by a much higher demand for donor lungs than can be supplied, leading to considerable waiting time and mortality among patients waiting for transplant. This has led to the search for an alternative bridging strategy in patients with end-stage lung disease. The use of extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation as well as a rescue strategy post-transplant for primary graft dysfunction (PGD) has been studied previously, however due to initially poor outcomes, its use was not heavily instituted. In recent years, with significant improvement in technologies, several single and multi-center studies have shown promising outcomes related to the use of ECMO as a bridging strategy as well as a therapy for patients suffering from PGD post-transplant. These results have challenged our current notion on ECMO use and hence forced us to reexamine the utility, efficacy and safety of ECMO in conjunction with lung transplantation. Through this review, we will address the various aspects related to ECMO use as a bridge to lung transplantation as well as a rescue post-transplant in the treatment of PGD. We will emphasize newer technologies related to ECMO use, examine recent observational studies and randomized trials of ECMO use before and after lung transplantation, and reflect upon our own institutional experience with the use of ECMO in these difficult clinical situations.

Disruptive technology in the treatment of thoracic trauma

The care of patients with thoracic injuries has undergone monumental change over the past 25 years. Advances in technology have driven improvements in care, with obvious benefits to patients. In many instances, new or "disruptive" technologies have unexpectedly displaced previously established standards for the diagnosis and treatment of these potentially devastating injuries. Examples of disruptive technology include the use of ultrasound technology for the diagnosis of cardiac tamponade and pneumothorax; thoracoscopic techniques instead of thoracotomy, pulmonary tractotomy, and stapled lung resection; endovascular repair of thoracic aortic injury; operative fixation of flail chest; and the enhanced availability of extracorporeal lung support for severe respiratory failure. Surgeons must be prepared to recognize the benefits, and limits, of novel technologies and incorporate these methods into day-to-day treatment protocols.

First experiences with a combined usage of veno-arterial and veno-venous ECMO in therapy-refractory cardiogenic shock patients with cerebral hypoxemia

The use of extracorporeal membrane oxygenation (ECMO) is becoming a popular tool in the treatment of cardiogenic shock. We present two case reports where classical veno-arterial peripherally cannulated ECMO therapy proved insufficient with profuse cerebral hypoxemia. After augmenting the setting into veno-veno-arterial ECMO, we achieved a remarkable improvement of all oxygenation parameters. The simultaneous use of veno-venous and veno-arterial ECMO might display as a novel strategy to counteract the coronary and cerebral hypoxemia in veno-arterial ECMO therapy in patients with therapy-refractory cardiogenic shock or in combined cardiopulmonary failure. In this manuscript, the veno-veno-arterial ECMO setup is described in full detail and different venous cannulas are discussed.

First experience with the deltastream(R) DP3 in venovenous extracorporeal membrane oxygenation and air-supported inter-hospital transport

OBJECTIVES

Based on continuous technical innovations and recent research, extracorporeal membrane oxygenation (ECMO) has become a promising tool in the treatment of patients with acute (cardio)pulmonary failure. Nevertheless, any extracorporeal technique requires a high degree of experience and knowledge, so that a restriction to specialized centres seems to be reasonable. As a consequence of this demand, the need for inter-hospital transfer of patients with severely impaired (cardio)pulmonary function is rising. Unfortunately, most of the ECMO devices used in the clinical setting are not suitable for inter-hospital transport because of their size, weight or complexity. In this article, we describe our first experiences with the airborne transport of 6 patients on a new portable, miniaturized and lightweight extracorporeal circulation system, the Medos deltastream® DP3.

METHODS

Six patients suffering acute respiratory failure were taken on venovenous ECMO (DP3) out-of-centre and transferred to the University Medical Center Regensburg by helicopter. All cardiorespiratory-relevant parameters of the patients and the technical functioning of the device were continuously monitored and documented.

RESULTS

Implantation of the device and air-supported transport were performed without any technical complications. The patients were transported from a distance of 66-178 km, requiring a time of 40-120 min. With the help of the new deltastream® DP3 ECMO device, a prompt stabilization of the cardiopulmonary function could be achieved in all patients. One patient was under ongoing cardiopulmonary resuscitation by the time our ECMO team arrived at the peripheral hospital and died shortly after arrival in the central emergency ward.

CONCLUSIONS

Our experience shows that the deltastream® DP3 is an absolutely reliable and safe ECMO device that could gain growing importance in the field of airborne transportation of patients on ECMO due to its unsophisticated, miniaturized and lightweight characteristics.

Extracorporeal membrane oxygenation circuitry

The extracorporeal membrane oxygenation circuit is made of a number of components that have been customized to provide adequate tissue oxygen delivery in patients with severe cardiac and/or respiratory failure for a prolonged period of time (days to weeks). A standard extracorporeal membrane oxygenation circuit consists of a mechanical blood pump, gas-exchange device, and a heat exchanger all connected together with circuit tubing. Extracorporeal membrane oxygenation circuits can vary from simple to complex and may include a variety of blood flow and pressure monitors, continuous oxyhemoglobin saturation monitors, circuit access sites, and a bridge connecting the venous access and arterial infusion limbs of the circuit. Significant technical advancements have been made in the equipment available for short- and long-term extracorporeal membrane oxygenation applications. Contemporary extracorporeal membrane oxygenation circuits have greater biocompatibility and allow for more prolonged cardiopulmonary support time while minimizing the procedure-related complications of bleeding, thrombosis, and other physiologic derangements, which were so common with the early application of extracorporeal membrane oxygenation. Modern era extracorporeal membrane oxygenation circuitry and components are simpler, safer, more compact, and can be used across a wide variety of patient sizes from neonates to adults.