Extracorporeal membrane oxygenation for acute respiratory distress syndrome: is the configuration mode an important predictor for the outcome?

Successful management of harlequin syndrome due to pulmonary hemorrhage and atelectasis with VAV- ECMO

INTRODUCTION

Pulmonary hemorrhage is a life-threatening complication of VA-ECMO occasionally presenting with Harlequin syndrome.

CASE REPORT

We present a case of a VA-ECMO patient complicated with pulmonary hemorrhage, complete right lung atelectasis and differential hypoxia refractory to conventional treatment including optimal mechanical ventilation and bronchoscopy interventions. Patient was successfully managed by conversion of VA to VAV-ECMO.

DISCUSSION

Pulmonary hemorrhage and atelectasis treatment in a VA-ECMO patient includes transfusion, hold and reversal of anticoagulation, bronchoscopy interventions and optimization of VA-ECMO and ventilator support. Differential hypoxia may ensue due to residual native cardiac function. If refractory to conservative treatment, a VAV-ECMO configuration may be utilized to improve upper body oxygenation by inserting an additional cannula to the superior vena cava.

CONCLUSION

VAV-ECMO is an ECMO configuration support in patients at risk of Harlequin syndrome presenting with pulmonary hemorrhage.

Hybrid extracorporeal membrane oxynegation in pediatric intensive care patients: A single center experience: More is better?

BACKGROUND

The initial extracorporeal membrane oxygenation (ECMO) configuration is inefficient for patient oxygenation and flow, but by adding a Y-connector, a third or fourth cannula can be used to support the system, which is called hybrid ECMO.

METHODS

This was a single-center retrospective study consisting of patients receiving hybrid and standard ECMO in our PICU between January 2014 and January 2022.

RESULTS

The median age of the 12 patients who received hybrid ECMO and were followed up with hybrid ECMO was 140 (range, 82-213) months. The total median ECMO duration of the patients who received hybrid ECMO was 23 (8-72) days, and the median follow-up time on hybrid ECMO was 18 (range, 3-46) days. The mean duration of follow-up in the PICU was 34 (range, 14-184) days. PICU length of stay was found to be statistically significant and was found to be longer in the hybrid ECMO group (p = 0.01). Eight (67%) patients died during follow-up with ECMO. Twenty-eight-day mortality was found to be statistically significant and was found to be higher in the standard ECMO group (p = 0.03). The hybrid ECMO mortality rate was 66% (decannulation from ECMO). The hybrid ECMO hospital mortality rate was 75%. The standard ECMO mortality rate was 52% (decannulation from ECMO). The standard ECMO hospital mortality rate was 65%.

CONCLUSIONS

Even though hybrid ECMO use is rare, with increasing experience and new methods, more successful experience will be gained. Switching to hybrid ECMO from standard ECMO at the right time with the right technique can increase treatment success and survival.

A Descriptive Analysis of Hybrid Cannulated Extracorporeal Life Support

BACKGROUND

Extracorporeal life support (ECLS) is pivotal for sustaining the function of failing hearts and lungs, and its utilization has risen. In cases where conventional cannulation strategies prove ineffective for providing adequate ECLS support, the implementation of an enhanced system with a third cannula may become necessary. Hybrid ECLS may be warranted in situations characterized by severe hypoxemia of the upper extremity, left ventricular congestion, and dilatation. Additionally, it may also be considered for patients requiring respiratory support or experiencing hemodynamic instability.

METHOD

All hybrid ECLS cases of adults at the University Hospital Zurich, Switzerland, between January 2007 and December 2019 with initial triple cannulation were included. Data were collected via a retrospective review of patient records and direct export of the clinical information system.

RESULTS

28 out of 903 ECLS cases were initially hybrid cannulated (3.1%). The median age was 57 (48.2 to 60.8) years, and the sex was equally distributed. The in-hospital mortality of hybrid ECLS was high (67.9%). In-hospital mortality rates differ depending on the indication (ARDS: 36.4%, refractory cardiogenic shock: 88.9%, cardiopulmonary resuscitation: 100%, post-cardiotomy: 100%, others: 75%). Survivors exhibited a lower SAPS II level compared with non-survivors (20.0 (12.0 to 65.0) vs. 55.0 (45.0 to 73.0)), and the allogenic transfusion of platelet concentrate was observed to be less frequent for survivors (0.0 (0.0) vs. 1.8 (2.5) units).

CONCLUSION

The in-hospital mortality rate for hybrid ECLS was high. Different indications showed varying mortality rates, with survivors having lower SAPS II scores and requiring fewer platelet concentrate transfusions. These findings highlight the complexities of hybrid ECLS outcomes in different clinical scenarios and underline the importance of rigorous patient selection.

The Outcome Relevance of Pre-ECMO Liver Impairment in Adults with Acute Respiratory Distress Syndrome

We hypothesize that (1) a significant pre-ECMO liver impairment, which is evident in the presence of pre-ECMO acute liver injury and a higher pre-ECMO MELD (model for end-stage liver disease) score, is associated with increased mortality; and (2) the requirement of veno-veno-arterial (V-VA) ECMO support is linked to a higher prevalence of pre-ECMO acute liver injury, a higher pre-ECMO MELD score, and increased mortality. We analyze 187 ECMO runs (42 V-VA and 145 veno-venous (V-V) ECMO) between January 2017 and December 2020. The SAPS II score is calculated at ICU admission; hepatic function and MELD score are assessed at ECMO initiation (pre-ECMO) and during the first five days on ECMO. SOFA, PRESERVE and RESP scores are calculated at ECMO initiation. Pre-ECMO cardiac failure, acute liver injury, ECMO type, SAPS II and MELD, SOFA, PRESERVE, and RESP scores are associated with mortality. However, only the pre-ECMO MELD score independently predicts mortality (p = 0.04). In patients with a pre-ECMO MELD score > 16, V-VA ECMO is associated with a higher mortality risk (p = 0.0003). The requirement of V-VA ECMO is associated with the development of acute liver injury during ECMO support, a higher pre-ECMO MELD score, and increased mortality.

Right ventricular dysfunction in patients with acute respiratory distress syndrome receiving venovenous extracorporeal membrane oxygenation

Acute respiratory distress syndrome is characterized by non-cardiogenic pulmonary edema, decreased pulmonary compliance, and abnormalities in gas exchange, especially hypoxemia. Patients with acute respiratory distress syndrome (ARDS) who receive support with venovenous (V-V) extracorporeal membrane oxygenation (ECMO) usually have severe lung disease. Many patients with ARDS have associated pulmonary vascular injury which can result in elevated pulmonary vascular resistance and right heart dysfunction. Since V-V ECMO relies upon preserved cardiac function, right heart failure has important implications for patient evaluation, management, and outcomes. Worsening right heart function complicates ARDS and disease processes. Given the increasing use of ECMO to support patients with ARDS, an understanding of right ventricular-ECMO and cardiopulmonary interactions is essential for the clinician. A narrative review of the manifestations of right heart dysfunction, as well as diagnosis and management strategies for the patient with ARDS on ECMO, is provided.

The American Association for Thoracic Surgery (AATS) 2022 Expert Consensus Document: The use of mechanical circulatory support in lung transplantation

OBJECTIVE

The use of mechanical circulatory support (MCS) in lung transplantation has been steadily increasing over the prior decade, with evolving strategies for incorporating support in the preoperative, intraoperative, and postoperative settings. There is significant practice variability in the use of these techniques, however, and relatively limited data to help establish institutional protocols. The objective of the AATS Clinical Practice Standards Committee (CPSC) expert panel was to review the existing literature and establish recommendations about the use of MCS before, during, and after lung transplantation.

METHODS

The AATS CPSC assembled an expert panel of 16 lung transplantation physicians who developed a consensus document of recommendations. The panel was broken into subgroups focused on preoperative, intraoperative, and postoperative support, and each subgroup performed a focused literature review. These subgroups formulated recommendation statements for each subtopic, which were evaluated by the entire group. The statements were then developed via discussion among the panel and refined until consensus was achieved on each statement.

RESULTS

The expert panel achieved consensus on 36 recommendations for how and when to use MCS in lung transplantation. These recommendations included the use of veno-venous extracorporeal membrane oxygenation (ECMO) as a bridging strategy in the preoperative setting, a preference for central veno-arterial ECMO over traditional cardiopulmonary bypass during the transplantation procedure, and the benefit of supporting selected patients with MCS postoperatively.

CONCLUSIONS

Achieving optimal results in lung transplantation requires the use of a wide range of strategies. MCS provides an important mechanism for helping these critically ill patients through the peritransplantation period. Despite the complex nature of the decision making process in the treatment of these patients, the expert panel was able to achieve consensus on 36 recommendations. These recommendations should provide guidance for professionals involved in the care of end-stage lung disease patients considered for transplantation.

Outcomes of patients with acute respiratory failure on veno-venous extracorporeal membrane oxygenation requiring additional circulatory support by veno-venoarterial extracorporeal membrane oxygenation

Objective

Veno-venous (V-V) extracorporeal membrane oxygenation (ECMO) is increasingly used to support patients with severe acute respiratory distress syndrome (ARDS). In case of additional cardio-circulatory failure, some experienced centers upgrade the V-V ECMO with an additional arterial return cannula (termed V-VA ECMO). Here we analyzed short- and long-term outcome together with potential predictors of mortality.

Design

Multicenter, retrospective analysis between January 2008 and September 2021.

Setting

Three tertiary care ECMO centers in Germany (Hannover, Bonn) and Switzerland (Zurich).

Patients

Seventy-three V-V ECMO patients with ARDS and additional acute cardio-circulatory deterioration required an upgrade to V-VA ECMO were included in this study.

Measurements and main results

Fifty-three patients required an upgrade from V-V to V-VA and 20 patients were directly triple cannulated. Median (Interquartile Range) age was 49 (28–57) years and SOFA score was 14 (12–17) at V-VA ECMO upgrade. Vasoactive-inotropic score decreased from 53 (12–123) at V-VA ECMO upgrade to 9 (3–37) after 24 h of V-VA ECMO support. Weaning from V-VA and V-V ECMO was successful in 47 (64%) and 40 (55%) patients, respectively. Duration of ECMO support was 12 (6–22) days and ICU length of stay was 32 (16–46) days. Overall ICU mortality was 48% and hospital mortality 51%. Two additional patients died after hospital discharge while the remaining patients survived up to two years (with six patients being lost to follow-up). The vast majority of patients was free from higher degree persistent organ dysfunction at follow-up. A SOFA score > 14 and higher lactate concentrations at the day of V-VA upgrade were independent predictors of mortality in the multivariate regression analysis.

Conclusion

In this analysis, the use of V-VA ECMO in patients with ARDS and concomitant cardiocirculatory failure was associated with a hospital survival of about 50%, and most of these patients survived up to 2 years. A SOFA score > 14 and elevated lactate levels at the day of V-VA upgrade predict unfavorable outcome.

Veno-arteriovenous (V-AV) ECMO configuration: A single-center experience

BACKGROUND

With increasing extracorporeal membrane oxygenation (ECMO) utilization over the last decade, clinicians have developed "hybrid" configurations to meet complex perfusion requirements. In the setting of differential hypoxemia, a veno-arteriovenous (V-AV) configuration provides oxygenated cardiac preload and hemodynamic support to satisfy physiologic demands. We aim to further characterize the patient population, indications, and outcomes associated with this hybrid configuration.

METHODS

We retrospectively reviewed all adult patients placed on V-AV ECMO at our institution from June 2016 to December 2019. Through a review of the electronic medical records, data describing demographic features, comorbidities, and ECMO-specific information were analyzed systematically.

RESULTS

14 patients were placed on V-AV ECMO during the study period. Our cohort was 79% male with a median age of 54 and BMI of 30.3. These patients had a median SOFA-0 score of 15 and SAVE score of -12. Patients were treated with ECMO support for a median of 144.1 (IQR 98.5 - 183.1) hours, consisting of 0.2 (IQR 0 - 17.7) hours of VA and 92.4 (IQR 53.7 - 115.1) hours of V-AV followed by 67.4 (IQR 20.3 - 96.6) hours of VV support. Of these 14 patients, 11 survived to decannulation (79%) and 9 survived to hospital discharge (64%).

CONCLUSION

ECMO patients with recovering left ventricular function and persistent gas exchange abnormalities are at risk for developing differential hypoxemia. We describe an approach to utilizing V-AV configuration when the likelihood of differential hypoxemia is extremely high, with a survival rate that compares favorably to Extracorporeal Life Support Organization statistics and published case series.

Dynamic and Hybrid Configurations for Extracorporeal Membrane Oxygenation: An Analysis of the Chinese Extracorporeal Life Support Registry

Dynamic or hybrid configurations for extracorporeal membrane oxygenation (ECMO) are needed when patient physiology or clinical conditions change. Dynamic configurations included configurations converting from veno-arterial (V-A) ECMO or veno-venous (V-V) ECMO to other forms. Hybrid configurations included venous-arteriovenous (V-AV) and venovenous-arterial (VV-A) ECMO. This study retrospectively analyzed a total of 3,814 ECMO cases (3,102 adult cases) reported to the Chinese Society of Extracorporeal Life Support from January 1, 2017 to December 31, 2019. Eight-three adult patients had dynamic or hybrid ECMO configurations, whose primary diagnoses included cardiogenic shock (33.7%), cardiac arrest (6.0%), acute respiratory failure (39.8%), septic shock (9.6%), multiple trauma (3.6%), pulmonary hypertension (3.6%), and others (3.6%). Configuration changes occurred in 37 patients with the initial configuration of VA (20 to VV, 13 to V-AV, and 4 to VV-A) and 27 with the initial configuration of VV (7 to VA, and 20 to V-AV). A total of 46 (55.4%) patients received hybrid configurations of V-AV and 10 (12.0%) received VV-A. Patients with the initial configuration of VV who converted to other configurations had higher in-hospital mortality (74.1%) than other initial configurations (VA 45.9%, V-AV 76.9%, VV-A 66.7%, P = 0.021). We concluded that dynamic or hybrid ECMO configurations were used in various underlying diseases, in which V-AV was most commonly used. Patients receiving VV ECMO for respiratory support initially, who then converted to other configurations for both respiratory and circulatory support, had significantly worst outcomes among the groups studied. The initial configuration should be selected carefully after thorough assessment of patient condition.

Acute Cor Pulmonale in a Critically Ill Patient with COVID-19 Resolved with Venoarteriovenous Extracorporeal Membrane Oxygenation

•Early detection of RV dysfunction may lead to decreased mortality in patients with COVID-19. •VAV-ECMO appears to be a viable treatment for patients with SARS-CoV-2 and RV failure. •Transesophageal echocardiogram played a critical role in therapeutic decisions.

2020 EACTS/ELSO/STS/AATS Expert Consensus on Post-cardiotomy Extracorporeal Life Support in Adult Patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

2020 EACTS/ELSO/STS/AATS expert consensus on post-cardiotomy extracorporeal life support in adult patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management, and avoidance of complications, appraisal of new approaches and ethics, education, and training.

Early Findings after Implementation of Veno-Arteriovenous ECMO: A Multicenter European Experience

Extracorporeal membrane oxygenation (ECMO) is increasingly used to treat cardiopulmonary failure in critically ill patients. Peripheral cannulation may be complicated by a persistent low cardiac output in case of veno-venous cannulation (VV-ECMO) or by differential hypoxia (e.g., lower PaO₂ in the upper than in the lower body) in case of veno-arterial cannulation (VA-ECMO) and severe impairment of pulmonary function associated with cardiac recovery. The treatment of such complications remains challenging. We report the early effects of the use of veno-arterial-venous (V-AV) ECMO in this setting. Methods: Retrospective analysis including patients from five different European ECMO centers (January 2013 to December 2016) who required V-AV ECMO. We collected demographic data as well as comorbidities and ECMO characteristics, hemodynamics, and arterial blood gas values before and immediately after (i.e., within 2 h) V-AV implementation. Results: A total of 32 patients (age 53 (interquartiles, IQRs: 31–59) years) were identified: 16 were initially supported with VA-ECMO and 16 with VV-ECMO. The median time to V-AV conversion was 2 (1–5) days. After V-AV implantation, heart rate and norepinephrine dose significantly decreased, while PaO₂ and SaO₂ significantly increased compared to baseline values. Lactate levels significantly decreased from 3.9 (2.3–7.1) to 2.8 (1.4–4.4) mmol/L (p = 0.048). A significant increase in the overall ECMO blood flow (from 4.5 (3.8–5.0) to 4.9 (4.3–5.9) L/min; p < 0.01) was observed, with 3.0 (2.5–3.2) L/min for the arterial and 2.8 (2.1–3.6) L/min for the venous return flows. Conclusions: In ECMO patients with differential hypoxia or persistently low cardiac output syndrome, V-AV conversion was associated with improvement in some hemodynamic and respiratory parameters. A significant increase in the overall ECMO blood flow was also observed, with similar flow distributed into the arterial and venous return cannulas.

The Effect of Additional Stepwise Venous Inflow on Differential Hypoxia of Veno-Arterial Extracorporeal Membrane Oxygenation

Use of femoral-femoral veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) for cardiopulmonary support during lung transplantation can be inadequate for efficient distribution of oxygenated blood into the coronary circulation. We hypothesized that creating a left-to-right shunt flow using veno-arterio-venous (VAV) ECMO would alleviate the differential hypoxia. Total 10 patients undergoing lung transplantation were enrolled in this study. An additional inflow cannula was inserted into the right internal jugular (RIJ) vein for VAV ECMO. During left one-lung ventilation using a 1.0 inspired oxygen fraction (FiO₂), the left-to-right shunt flow was incrementally increased from 0 to 500, 1,000, and 1,500 ml/min. The arterial oxygen partial pressure (PaO₂) and oxygen saturation (SaO₂) were measured at the proximal ascending aorta and right radial artery. The ascending aorta gas analysis revealed that six patients had a PaO₂/FiO₂ ratio less than 200 mm Hg at a 0 ml/min shunt flow. The PaO₂ (SaO₂) values were 48.5 ± 14.8 mm Hg (80.9 ± 11.6%) at the ascending aorta and 77.8 ± 69.7 mm Hg (83.3 ± 13.2%) at the right radial artery. As the left-to-right shunt flow rate increased over 1,000 ml/min, the PaO₂ and SaO₂ values for the ascending aorta and right radial artery significantly increased. In conclusion, femoral-femoral VA ECMO can produce suboptimal coronary oxygenation in patients unable to tolerate one-lung ventilation. A left-to-right shunt using VAV ECMO can alleviate the differential hypoxia.

[Extracorporeal Lung Support in Thoracic Surgery: Basics and Pathophysiology]

Extracorporeal lung support (ECLS) is of increasing importance in general thoracic surgery. Different modes of ECLS may be applied in several situations throughout the perioperative phase and are adapted to the individual patient's needs and the planned surgical procedures. ECLS is not a static procedure and should be always evaluated according to the present condition of the patient. Therefore, it is essential to understand the pathophysiology of the disease and the different ECLS modes, as well as the different cannulation options, in order to be able to use the different escalation and de-escalation techniques in accordance with the clinical situation.

Dual RVAD-ECMO Circuits to Treat Cardiogenic Shock and Hypoxemia Due to Necrotizing Lung Infection: A Case Report

Utilization of venoarterial extracorporeal membrane oxygenation (VA-ECMO) is expanding, but dual VA-ECMO circuits to treat cardiogenic shock with refractory hypoxemia is unreported. We describe the case of combined cardiogenic and distributive shock due to necrotizing pulmonary blastomycosis. After initial central VA-ECMO cannulation, acute respiratory distress syndrome (ARDS) with increasing shunt resulted in significant central hypoxemia due to progressive ventilation-perfusion mismatch. An additional circuit provided complete oxygenation of the high circulating volume. After 4 months on support, he underwent successful heart-lung-kidney transplantation. Dual ECMO circuits are technically feasible and may be advantageous in specific circumstances of high pulmonary shunting resulting in excessive hypoxemia unbalanced with appropriate oxygen delivery.

2020 EACTS/ELSO/STS/AATS expert consensus on post-cardiotomy extracorporeal life support in adult patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

2020 EACTS/ELSO/STS/AATS Expert Consensus on Post-Cardiotomy Extracorporeal Life Support in Adult Patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

An experimental model of veno-venous arterial extracorporeal membrane oxygenation

INTRODUCTION

Veno-venous arterial extracorporeal membrane oxygenation is a hybrid-modality of extracorporeal membrane oxygenation combining veno-venous and veno-arterial extracorporeal membrane oxygenation. It may be applied to patients with both respiratory and cardio-circulatory failure.

AIM

To describe a computational spreadsheet regarding an ex vivo experimental model of veno-venous arterial extracorporeal membrane oxygenation to determine the return of cannula pairs in a single pump-driven circuit.

METHODS

We developed an ex vivo model of veno-venous arterial extracorporeal membrane oxygenation with a single pump and two outflow cannulas, and a glucose solution was used to mimic the features of blood. We maintained a fixed aortic impedance and physiological pulmonary resistance. Both flow and pressure data were collected while testing different pairs of outflow cannulas. Six simulations of different cannula pairs were performed, and data were analysed by a custom-made spreadsheet, which was able to predict the flow partition at different flow levels.

RESULTS

In all simulations, the flow in the arterial cannula gradually increased differently depending on the cannula pair. The best cannula pair was a 19-Fr/18-cm arterial with a 17-Fr/50-cm venous cannula, where we observed an equal flow split and acceptable flow into the arterial cannula at a lower flow rate of 4 L/min.

CONCLUSION

Our computational spreadsheet identifies the suitable cannula pairing set for correctly splitting the outlet blood flow into the arterial and venous return cannulas in a veno-venous arterial extracorporeal membrane oxygenation configuration without the use of external throttles. Several limitations were reported regarding fixed aortic impedance, central venous pressure and the types of cannulas tested; therefore, further studies are mandatory to confirm our findings.

Further options and survival results after failure following extracorporeal life support implantation

BACKGROUND

A retrospective study was designed to analyze the outcome of patients with extracorporeal life support (ECLS) who needed a consecutive cardiac or pulmonary support system.

METHODS

From 2006 to 2016, 93 out of 587 patients with their age ranging from 2.4 to 77.3 years required an exchange of an ECLS by another mechanical support system. Sixty-one patients were inhospital cases, 39 patients were referred with ECLS from other institutions by ambulance car (N.=15) or helicopter (N.=24). Sixty-five patients came from internal medicine wards, of which 38 patients had CPR, whereas 24 patients suffered postcardiotomy failure with CPR in 11 cases. Ten patients were referred from other hospitals for failure to wean from ECLS.

RESULTS

Leading symptoms were continuing cardiac failure in 43 patients (46%) and ongoing respiratory failure after cardiac recovery in 50 patients (54%). Patients with cardiac failure underwent implantation of a ventricular assist device (N.=36) or remained on long-term ECLS (N.=7) until a donor organ for heart transplantation was available (mean waiting time 43 days). Respiratory failure was treated by veno-venous ECMO (N.=34) or vav-ECMO (N.=16). Overall inhouse survival was 50.5% (N.=47). Only 22.6% of patients (N.=21) died during ongoing support. In contrast, 26.9% of patients (N.=25) deceased 35+/-51 days after weaning from vv- or vav-ECMO. Major reasons of death were multi-organ failure in 16 patients, cerebral hypoxia in 12 patients, sepsis in 10 patients, and intractable ow output in 5 patients.

CONCLUSIONS

Despite a switch from ECLS to another mechanical support system, survival remains limited as irreversible multi-organ failure and sepsis still jeopardize the patients' life.

Hybrid extracorporeal membrane oxygenation

Veno-venous (VV) and veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) therapy is widely used in critically ill patients with refractory cardiogenic shock and cardiac arrest or suffering from severe respiratory failure. Besides traditional ECMO cannulation, changes in patients' conditions or the occurrence of specific complications (i.e., cerebral hypoxia or left ventricular dilation) may require modifications in cannulation strategies or the combination of ECMO with additional invasive or minimally invasive procedures, to improve organ function and ECMO efficiency. In this review, we described all these "hybrid" approaches, such as the addition of a third or fourth ECMO cannula to improve venous drainage and/or optimize systemic hemodynamics/oxygenation, or the implementation of surgical or percutaneous unloading of the left ventricle (LV), to reduce cardiac dilation and pulmonary edema. Although few data are still available about the effectiveness of such interventions, clinicians should be aware of these advances in ECMO management to improve the management of more complex cases.

Rituximab Induced Pulmonary Edema Managed with Extracorporeal Life Support

Though rare, rituximab has been reported to induce severe pulmonary edema. We describe the first report of ECLS utilization for this indication. A 31-year-old female with severe thrombotic thrombocytopenic purpura developed florid pulmonary edema after rituximab infusion. Despite advanced ventilatory settings, she developed severe respiratory acidosis and remained hypoxemic with a significant vasopressor requirement. Since her pulmonary insult was likely transient, ECLS was considered. Due to combined cardiorespiratory failure, she received support with peripheral venoarterial ECLS. During her ECLS course, she received daily plasmapheresis and high dose steroids. Her pulmonary function recovered and she was decannulated after 8 days. She was discharged after 23 days without residual sequelae.

Predictable capability control scheme for oxygen-exchange blood flow regulation in an extracorporeal membrane oxygenation system

Extracorporeal membrane oxygenation system is used for rescue treatment strategies for temporary cardiopulmonary function support to facilitate adequately oxygenated blood to return into the systemic and pulmonary circulation systems. Therefore, a servo flow regulator is used to adjust the roller motor speed, while support blood flow can match the sweep gas flow (GF) in a membrane oxygenator. A generalised regression neural network is designed as an estimator to automatically estimate the desired roller pump speed and control parameters. Then, the proportional-integral-derivative controller with tuning control parameters showed good performance to achieve speed regulation and speed tracking in the desired operating point. Given the pressure of carbon dioxide, drainage blood flow, and cannula size, the proposed predictable capability control scheme can be validated to meet the intended uses in clinical applications.

Pitfalls of cannulation for extracorporeal life support: review of the literature and illustrative case presentation

Extracorporeal membrane oxygenation (ECMO) and extracorporeal life support (ECLS) are an increasingly established advanced therapy for emerging severe lung and/or cardiocirculatory dysfunction or failure. Several reports have provided evidence for a potential benefit in prognosis by ECLS in cases of cardiogenic shock including cardiopulmonary resuscitation. Routine use in specialized centers reduces the incidence of negative side effects (e.g., vascular/ischemic, embolic, hemorrhagic, hemolytic and, furthermore, septic). Vascular complications like not only limb ischemia but also hypoxia proximal to the cannulation site up to complete sectorial hypoxia called "harlequin phenomenon" could refer to be a major adverse event in ECLS which, therefore, should be limited primarily to cardiocirculatory indications. Here we report on a case with "harlequin phenomenon" after ECLS implementation as a relevant complication of the mode of cannulation and review benefits and risks of commonly used variants of vascular access.

ECMO in cardiac arrest and cardiogenic shock

Cardiogenic shock is an acute emergency, which is classically managed by medical support with inotropes or vasopressors and frequently requires invasive ventilation. However, both catecholamines and ventilation are associated with a worse prognosis, and many patients deteriorate despite all efforts. Mechanical circulatory support is increasingly considered to allow for recovery or to bridge until making a decision or definite treatment. Of all devices, extracorporeal membrane oxygenation (ECMO) is the most widely used. Here we review features and strategical considerations for the use of ECMO in cardiogenic shock and cardiac arrest.

Escalation of extracorporeal life support as a bridge to lung transplantation in end-stage lung disease

Extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplant (LTx) is not uncommon, but it is not commonplace yet. We present a case of a 45-year-old man with cystic fibrosis with recent deterioration in lung function who was initially supported with veno-venous (VV) ECMO. However, he subsequently required conversion to veno-veno-arterial (VVA) ECMO. After 21 days of support, he underwent double lung transplantation, with an uneventful postoperative course. This case shows that, in patients with end-stage respiratory failure awaiting lung transplantation, extracorporeal life support may require escalation to improve gas exchange and address circulatory requirements.

Impact of age on extracorporeal membrane oxygenation survival of patients with cardiac failure

Purpose

Extracorporeal membrane oxygenation (ECMO) is used to treat patients in critical condition with cardiogenic shock. However, few studies have examined the effect of old age in ECMO survival. This study analyzed the impact of age on ECMO survival of patients with cardiac failure, and analyzed predictive factors for survival according to age.

Materials and methods

We retrospectively reviewed the medical records of 95 patients who required veno-arterial (V-A) ECMO between May 2009 and May 2016 at a single center. Patients were classified into “age ≥65” (n=48, 50.5%) and “age <65” (n=47, 49.5%) groups.

Results

The age ≥65 group was significantly associated with increased mortality (HR: 1.715; 95% CI =1.038–2.831) at 90 days after ECMO initiation. These associations were attenuated and did not retain statistical significance after adjustment for comorbidities (HR: 1.485; 95% CI =0.844–2.614). To determine predictive factors of mortality, multivariate logistic analysis revealed that age ≥65 (OR 5.750; 95% CI [1.508–21.920]; P=0.010), low pre-ECMO serum bicarbonate (OR 0.884; 95% CI [0.788–0.991]; P=0.035), and high pre-ECMO serum creatinine (OR 4.546; 95% CI [1.021–20.239]; P=0.047) were significantly associated with survival to 90 days. By analyzing two groups separately, high pre-ECMO serum potassium level (OR 3.552; 95% CI [1.023–12.331]; P=0.046) was the only independent predictor in patients aged <65 years while low Glasgow Coma Scale score (OR 0.698; 95% CI [0.478–1.019]; P=0.063) showed a considerable trend toward significance in patients aged ≥65.

Conclusion

Older age was not an independent risk factor for mortality at 90 days among V-A ECMO patients. In addition, our study provides understanding of the differences in predictive factors for ECMO survival according to age. Pre-ECMO laboratory findings and mental status can assist clinicians in the prediction of a patient’s prognosis.

Childhood Obesity and Extracorporeal Membrane Oxygenation: Special Considerations for Successful Outcomes

The effects of obesity on venoarterial extracorporeal membrane oxygenation (VA-ECMO) outcomes in pediatric population are unknown. We performed retrospective analysis of 41 children (age 2-18 years) undergoing VA-ECMO. The percentage difference between actual body weight and lean body weight, referred to as Δmass, was calculated. Ratios of Δmass to ECMO flow were calculated at 4 and 24 hours. In patients with Δmass:flow ≥ 0.1 at 4 hours, higher 24-hour lactates (20.0 vs. 14.5 mg/dL; p = 0.002) and inotrope scores (17.3 vs. 11.2; p = 0.015) were observed. However, elevated Δmass:flow was not associated with mortality, and in-hospital mortality rates between groups were similar (53 vs. 45%; p = 0.647). In obese pediatric patients requiring VA-ECMO, increased flow is necessary to avoid complications of hypoperfusion and related complications.

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.

Veno-venous extracorporeal membrane oxygenation: cannulation techniques

The development of extracorporeal membrane oxygenation (ECMO) technology allows a new approach for the intensive care management of acute cardiac and/or respiratory failure in adult patients who are not responsive to conventional treatment. Current ECMO therapies provide a variety of options for the multidisciplinary teams who are involved in the management of these critically ill patients. In this regard, veno-venous ECMO (VV-ECMO) can provide quite complete respiratory support, even if this highly complex technique presents substantial risks, such as bleeding, thromboembolic events and infection. While VV-ECMO circuits usually include the cannulation of two vessels (double cannulation) in its classic configuration, the use of a single cannula is now possible for VV-ECMO support. Recently, experienced centers have employed more advanced approaches by cannulating three vessels (triple cannulation) which follows veno-arterio-venous (VAV) or veno-arterio-pulmonary-arterial cannulation (VAPa). However, 'triple' cannulation expands the field of application but increases the complexity of ECMO systems. In the present review, the authors focus on the indications for VV-ECMO, patient assessment prior to cannulation, the role of ultrasound-guided vessel puncture, double lumen single bicaval cannulations, and finally triple cannulation in VV-ECMO.

Cannulation strategies for percutaneous extracorporeal membrane oxygenation in adults

Extracorporeal membrane oxygenation (ECMO) has revolutionized treatment of severe isolated or combined failure of lung and heart. Due to remarkable technical development the frequency of use is growing fast, with increasing adoption by interventional cardiologists independent of cardiac surgery. Nevertheless, ECMO support harbors substantial risk such as bleeding, thromboembolic events and infection. Percutaneous ECMO circuits usually comprise cannulation of two large vessels ('dual' cannulation), either veno-venous for respiratory and veno-arterial for circulatory support. Recently experienced centers apply more advanced strategies by cannulation of three large vessels ('triple' cannulation), resulting in veno-veno-arterial or veno-arterio-venous cannulation. While the former intends to improve drainage and unloading, the latter represents a very potent method to provide circulatory and respiratory support at the same time. As such triple cannulation expands the field of application at the expense of increased complexity of ECMO systems. Here, we review percutaneous dual and triple cannulation strategies for different clinical scenarios of the critically ill. As there is no unifying terminology to date, we propose a nomenclature which uses "A" and all following letters for supplying cannulas and all letters before "A" for draining cannulas. This general and unequivocal code covers both dual and triple ECMO cannulation strategies (VV, VA, VVA, VAV). Notwithstanding the technical evolution, current knowledge of ECMO support is mainly based on observational experience and mostly retrospective studies. Prospective controlled trials are urgently needed to generate evidence on safety and efficacy of ECMO support in different clinical settings.

Short-term and longer-term survival after veno-arterial extracorporeal membrane oxygenation in an adult patient population: does older age matter?

Background:

Veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) is increasingly being used for patients with refractory cardiopulmonary failure. This study evaluates the short-term (to discharge) and longer-term (1 year) survival among older (⩾65 years) versus younger (<65 years) adults, adjusted for comorbidities, in a diverse cohort of V-A ECMO patients.

Methods:

This was a retrospective cohort analysis of 131 adult patients (28% ⩾65 years old) who received V-A ECMO at an academic medical center from 2004-2013. Demographics, comorbidities and surgical characteristics were abstracted from the medical records and verified. Mortality status at discharge and at one year post-ECMO were determined by the hospital clinical information system, updated monthly with Social Security Death Index data. Cox proportional hazard analyses were conducted to evaluate associations between age strata and mortality at discharge and at one year post ECMO initiation, adjusted for covariates.

Results:

The survival rate following V-A ECMO was 48% (n=68/131) to discharge and 44% (n=58/131) to one year. Age ⩾65 versus <65 was significantly associated with increased mortality during hospitalization (HR:2.03; 95%CI=1.23-3.33) and at one year (HR:1.81; 95% CI=1.12-2.93); these associations were attenuated and did not retain statistical significance after adjustment for comorbidities (HR:1.61; 95%CI=0.90-2.88 and HR:1.42; 95% CI=0.81-2.50, respectively). Statistically significant predictors of mortality at discharge and one year included history of coronary artery bypass graft, peripheral vascular disease and renal failure/dialysis (p<0.05).

Conclusions:

Older age was not independently associated with short-term or longer-term survival among V-A ECMO patients, but may reflect greater comorbidity, suggesting that age alone may not disqualify patients from V-A ECMO therapy.

Extracorporeal Membrane Oxygenation Applications in Cardiac Critical Care

The use of extracorporeal membrane oxygenation therapy (ECMO) in cardiac critical care has steadily increased over the past decade. Significant improvements in the technology associated with ECMO have propagated this recent resurgence and contributed to improved patient outcomes in the fields of cardiac and transplant (heart and lung) surgery. Specifically, ECMO is being increasingly utilized as a bridge to heart and lung transplantation, as well as to ventricular assist device placement. ECMO is also employed during the administration of cardiopulmonary resuscitation, known as extracorporeal life support. In this review, we examine the recent literature regarding the applications of ECMO and also describe emerging topics involving current ECMO management strategies.

Veno-venous extracorporeal membrane oxygenation in a patient with severe acute respiratory failure - case report

Acute respiratory failure resistant to conventional pulmonary therapy often requires intensive medical care. In rare cases, ventilator therapy proves insufficient, and only the option of employing veno-venous extracorporeal membrane oxygenation (ECMO V-V) remains. The present article describes the case of a 23-year-old patient who experienced severe acute respiratory distress syndrome with associated multiple organ failure. The patient was admitted to the pulmonary ward of the Alfred Sokołowski Regional Pulmonary Hospital in Szczecin-Zdunowo with suspected pneumonia of unknown etiology. After the initial 5 days of diagnostics at the pulmonary ward, the patient required a further 97 days of hospital treatment and spent 63 days at the Intensive Care Unit. There, he underwent ECMO V-V therapy lasting 22 days, which resulted in the improvement of his arterial blood gas parameters and clinical condition.

Veno-veno-arterial extracorporeal membrane oxygenation for respiratory failure with severe haemodynamic impairment: technique and early outcomes

OBJECTIVES

Patients with respiratory failure may benefit from veno-venous and veno-arterial extracorporeal membrane oxygenation (ECMO) support. We report on our initial experience of veno-veno-arterial (v-v-a) ECMO in patients with respiratory failure.

METHODS

Between January 2012 and February 2014, 406 patients required ECMO support at our institution. Here, we retrospectively analysed the characteristics and outcomes of patients commenced on either veno-venous or veno-arterial ECMO due to respiratory failure, and then switched to v-v-a ECMO.

RESULTS

Ten (2%) patients proceeded to v-v-a ECMO. The underlying conditions were acute respiratory distress syndrome (n = 3), end-stage pulmonary fibrosis (n = 5) and respiratory failure after major thoracic surgery (n = 1) and Caesarean section (n = 1). In all of these patients, ECMO was initially started as veno-venous (n = 9) or veno-arterial (n = 1) ECMO but was switched to a veno-veno-arterial (v-v-a) approach after a mean of 2 (range, 0-7) days. Reasons for switching were: haemodynamic instability (right heart failure, n = 5; pericardial tamponade, n = 1; severe mitral valve regurgitation, n = 1; haemodynamic instability following cardiopulmonary resuscitation, n = 1 and evidence of previously unknown atrial septal defect with pulmonary hypertension and Eisenmenger syndrome, n = 1) and upper-body hypoxaemia (n = 1). ECMO-related complications were bleeding (n = 3) and leg ischaemia (n = 2). Seven patients were successfully taken off ECMO with 4 being bridged to recovery and a further 3 to lung transplantation after a mean of 11 (range, 9-18) days. Five patients survived until hospital discharge and all of them were alive at the end of the follow-up.

CONCLUSIONS

Veno-veno-arterial ECMO is a technically feasible rescue strategy in treating patients presenting with combined respiratory and haemodynamic failure.

[Acute respiratory distress syndrome and septic cardiomyopathy : successful application of veno-venoarterial extracorporeal membrane oxygenation]

A 30-year-old patient was admitted to hospital with fever and respiratory insufficiency due to community acquired pneumonia. Within a few days the patient developed septic cardiomyopathy and severe acute respiratory distress syndrome (ARDS) which deteriorated under conventional mechanical ventilation. Peripheral venoarterial extracorporeal membrane oxygenation (va-ECMO) was initiated by the retrieval team of an ARDS/ECMO centre at a paO2/FIO2 ratio of 73 mmHg and a left ventricular ejection fraction (EF) of 10 %. After 12 h va-ECMO was converted to veno-venoarterial ECMO (vva-ECMO) for improvement of pulmonary and systemic oxygenation. Left ventricular function improved (EF 45 %) 36 h after starting ECMO and the patient was weaned from vva-ECMO and converted to vv-ECMO. The patient was weaned successfully from vv-ECMO after 5 additional days and transferred back to the referring hospital for weaning from the ventilator.

Extracorporeal membrane oxygenation with double venous drainage

We report on a successful configuration strategy of extracorporeal membrane oxygenation(ECMO) in two consecutive cases of acute lung injury. A 60-year-old woman with Streptococcus pneumoniae infection and a 22-year-old man with hemothorax were admitted to our hospital with failing lungs. Although treatment with a ventilator was started, oxygenation could not be maintained. ECMO with a femoro-femoral circuit was performed, which showed a slight improvement in oxygenation. However, not enough oxygen support was provided. To minimize the venous mixture at the right atrium, we added venous drainage from the right jugular vein which resulted in better oxygenation and patient survival.

Extracorporeal membrane oxygenation (ECMO) in patients with H1N1 influenza infection: a systematic review and meta-analysis including 8 studies and 266 patients receiving ECMO

Introduction

H1N1 influenza can cause severe acute lung injury (ALI). Extracorporeal membrane oxygenation (ECMO) can support gas exchange in patients failing conventional mechanical ventilation, but its role is still controversial. We conducted a systematic review and meta-analysis on ECMO for H1N1-associated ALI.

Methods

CENTRAL, Google Scholar, MEDLINE/PubMed and Scopus (updated 2 January 2012) were systematically searched. Studies reporting on 10 or more patients with H1N1 infection treated with ECMO were included. Baseline, procedural, outcome and validity data were systematically appraised and pooled, when appropriate, with random-effect methods.

Results

From 1,196 initial citations, 8 studies were selected, including 1,357 patients with confirmed/suspected H1N1 infection requiring intensive care unit admission, 266 (20%) of whom were treated with ECMO. Patients had a median Sequential Organ Failure Assessment (SOFA) score of 9, and had received mechanical ventilation before ECMO implementation for a median of two days. ECMO was implanted before inter-hospital patient transfer in 72% of cases and in most patients (94%) the veno-venous configuration was used. ECMO was maintained for a median of 10 days. Outcomes were highly variable among the included studies, with in-hospital or short-term mortality ranging between 8% and 65%, mainly depending on baseline patient features. Random-effect pooled estimates suggested an overall in-hospital mortality of 28% (95% confidence interval 18% to 37%; I² = 64%).

Conclusions

ECMO is feasible and effective in patients with ALI due to H1N1 infection. Despite this, prolonged support (more than one week) is required in most cases, and subjects with severe comorbidities or multiorgan failure remain at high risk of in-hospital death.