Use Of Extracorporeal Membrane Oxygenation Research Articles

Endothelial and Hemodynamic Function in a Large Animal Model in Relation to Different Extracorporeal Membrane Oxygenation Cannulation Strategies and Intra-Aortic Balloon Pumping.

The use of simultaneous veno-arterial extracorporeal membrane oxygenation (ECMO) with or without an Intra-Aortic Balloon Pump (IABP) is a widely used tool for mechanical hemodynamic support. Endothelial function, especially in relation to different cannulation techniques, is rarely investigated in the setting of extracorporeal life support (ECLS). In this study, we analyzed endothelial function in relation to hemodynamic and laboratory parameters for central and peripheral ECMO, with or without concomitant IABP support in a large animal model to gain a better understanding of the underlying basic mechanisms. In this large animal model, healthy female pigs with preserved ejection fraction were divided into the following groups related to cannulation strategy for ECMO and simultaneous IBAP support: control (no ECMO, no IABP), peripheral ECMO (pECMO), central ECMO (cECMO), pECMO and IABP or cECMO and IABP. During the experimental setting, the blood flow in the ascending aorta, left coronary artery and arteria carotis was measured. Afterwards, endothelial function was investigated after harvesting the right coronary artery, arteria carotis and renal artery. In addition, laboratory markers, such as creatine kinase (CK), creatine kinase muscle-brain (CK-MB), troponin, creatinine and endothelin were analyzed. The blood flow in the ascending aorta and the left coronary artery was significantly lower in all discussed experimental settings compared to the control group. Of note, the cECMO cannulation strategy generated favorable hemodynamic circumstances with higher blood flow in the coronary arteries than pECMO regardless of flow circumstances in the ascending aorta. The concomitant usage of IABP did not result in an improvement of the coronary blood flow, but partially showed a negative impact on the endothelial function of coronary arteries in comparison to the control. These findings correlate to higher CK/CK-MB levels in the setting of cECMO + IABP and pECMO + IABP. The usage of mechanical circulatory support with concomitant ECMO and IABP in a large animal model might have an influence on the endothelial function of coronary arteries while not improving the coronary artery perfusion in healthy hearts with preserved ejection.

Trends in Treatment Patterns and Outcomes of Patients With Pulmonary Embolism in Japan, 2010 to 2020: A Nationwide Inpatient Database Study.

Background The impact of major changes in the treatment practice of pulmonary embolism (PE), such as limited indications for systemic thrombolysis and the introduction of direct oral anticoagulants, is not well documented. This study aimed to describe annual trends in the treatment patterns and outcomes in patients with PE. Methods and Results Using the Japanese Diagnosis Procedure Combination inpatient database from April 2010 to March 2021, we identified hospitalized patients with PE. Patients with high-risk PE were defined as those admitted for out-of-hospital cardiac arrest or who received cardiopulmonary resuscitation, extracorporeal membrane oxygenation, vasopressors, or invasive mechanical ventilation on the day of admission. The remaining patients were defined as patients with non-high-risk PE. The patient characteristics and outcomes were reported with fiscal year trend analyses. Of 88 966 eligible patients, 8116 (9.1%) had high-risk PE, and the remaining 80 850 (90.9%) had non-high-risk PE. Between 2010 and 2020, in patients with high-risk PE, the annual proportion of extracorporeal membrane oxygenation use significantly increased from 11.0% to 21.3%, whereas that of thrombolysis use significantly decreased from 22.5% to 15.5% (P for trend <0.001 for both). In-hospital mortality significantly decreased from 51.0% to 43.7% (P for trend=0.04). In patients with non-high-risk PE, the annual proportion of direct oral anticoagulant use increased from 0.0% to 38.3%, whereas that of thrombolysis use significantly decreased from 13.7% to 3.4% (P for trend <0.001 for both). In-hospital mortality significantly decreased from 7.9% to 5.4% (P for trend <0.001). Conclusions Substantial changes in the PE practice and outcomes occurred in patients with high-risk and non-high-risk PE.

Veno-arterial extracorporeal membrane oxygenation versus standard medical management for massive pulmonary embolism.

There is limited research on the use and outcomes of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment for massive pulmonary embolism (PE). This study compared VA-ECMO treatment for massive PE versus patients treated medically. Patients diagnosed with massive PE at one hospital system were reviewed. VA-ECMO and non-ECMO groups were compared by t test and Chi-square. Mortality risk factors were identified by logistic regression. Survival was assessed by Kaplan Meier and propensity matching of groups. Ninety-two patients were included (22 VA-ECMO and 70 non-ECMO). Age (OR 1.08, 95% CI 1.03-1.13), arterial SBP (OR 0.97, 95% CI 0.94-0.99), albumin (OR 0.3, 95% CI 0.1-0.8), and phosphorus (OR 2.0, 95% CI 1.4-3.17) were independently associated with 30-day mortality. Alkaline phosphate (OR 1.03, 95% CI 1.01-1.05) and SOFA score (OR 1.3, 95% CI 1.06-1.51) were associated with 1-year mortality. Propensity matching showed no difference in 30-day (59% VA-ECMO versus 72% non-ECMO, p = 0.363) or 1-year survival (50% VA-ECMO versus 64% non-ECMO, p = 0.355). Patients treated with VA-ECMO for massive PE and medically treated patients have similar short- and long-term survival. Further research is needed to define clinical recommendations and benefits of intensive therapy such as VA-ECMO in this critically ill population.

New and personalized ventilatory strategies in patients with COVID-19.

Coronavirus disease (COVID-19) is caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) virus and may lead to severe respiratory failure and the need for mechanical ventilation (MV). At hospital admission, patients can present with severe hypoxemia and dyspnea requiring increasingly aggressive MV strategies according to the clinical severity: noninvasive respiratory support (NRS), MV, and the use of rescue strategies such as extracorporeal membrane oxygenation (ECMO). Among NRS strategies, new tools have been adopted for critically ill patients, with advantages and disadvantages that need to be further elucidated. Advances in the field of lung imaging have allowed better understanding of the disease, not only the pathophysiology of COVID-19 but also the consequences of ventilatory strategies. In cases of refractory hypoxemia, the use of ECMO has been advocated and knowledge on handling and how to personalize strategies have increased during the pandemic. The aims of the present review are to: (1) discuss the evidence on different devices and strategies under NRS; (2) discuss new and personalized management under MV based on the pathophysiology of COVID-19; and (3) contextualize the use of rescue strategies such as ECMO in critically ill patients with COVID-19.

RWD152 Real-World Evidence on the Use of Ecmo in Hospitalized COVID-19 Patients: Results from a Linked Closed and Open Claims Database in the US

To describe the use of extracorporeal membrane oxygenation (ECMO) among hospitalized coronavirus disease 2019 (H-COVID-19) patients in a linked closed claims (CC) and open claims (OC) database. This analysis identified H-COVID-19 patients between April 2020 (Q2 2020) and June 2022 (Q2 2022) in CHRONOS, a linked CC and OC database. The index event was the date of hospitalization, defined as an inpatient claim within 21 days of a COVID-19 diagnosis in the CC. The occurrence of ECMO 30 days after index was identified using CC data alone and then CC and OP data in combination to assess missing data. Study exclusions included patients under the age of 18, a first COVID-19 diagnosis that did not result in hospitalization, and less than 12-months of continuous enrollment in the CC before index. Study criteria were defined by the presence of an ICD-10-CM, ICD-10-PCS, or CPT code on a claim. Results are reported as percentages and 95% confidence intervals. Of 321,687 patients with H-COVID-19, the mean age was 50.1 (SD:12.8) with the highest proportion of hospitalizations occurring in Q3 2021 (19.4%). Overall, 0.50% (0.48%-0.52%) of patients in the CC data received ECMO, increasing to 0.61% (0.58%-0.64%) with the inclusion of OC data. The use of ECMO to treat H-COVID-19 patients decreased between Q2 2021 and Q2 2022, with the highest rates occurring in Q2 of 2020 (0.78%) and Q2 2021 (0.80%). The addition of OC data increased rates to 1.12% and 0.89% in Q2 of 2020 and Q2 2021. Although use of ECMO decreased in the later months of the pandemic, it represents a substantial burden. The current analysis demonstrates that CC data, often sourced from payers, may underestimate the use of ECMO in real-world settings. Opportunities exist to mitigate issues of missing data by linking CC, OC, and other real-world data sources.

P3: ECMO and Calcium Channel Blocker Overdose: A Systematic Review

Introduction: The increasing indications and prevalence of extracorporeal membrane oxygenation (ECMO) are evident by the exponential increase in ECMO in the last decade. In recent literature, ECMO use has sustained patients who have intentionally or unintentionally overdosed on cardiac medications. Specifically, calcium channel blocker overdose (CCBOD) can lead to significant cardiopulmonary dysfunction and has increased in recent years. Calcium channel blockers (CCB) block L-type voltage gated calcium channels throughout the body, and overdose results in cardiac depression, vasoplegia, and hyperglycemia. Expert consensus and poison control centers both recommend treatment with calcium, high dose insulin, inotropes, and vasopressors. Our systematic review evaluated when to initiate ECMO in the CCBOD population and the mortality rate with ECMO use. Methods: An electronic literature review was conducted to identify all relevant studies for CCB use and ECMO. PRISMA guidelines for systematic review were followed. Rayyan was used as a screening tool for blinding the authors from each other, and abstracts and full texts were reviewed by three independent authors. Inclusion criteria were strictly limited to CCB ingestion without polypharmacy. A data collection tool was devised and data was independently collected by two authors prior to statistical analysis. Data points included demographics, a list of currently recommended medical treatments for CCBOD, ECMO cannulation type, and survival to hospital discharge. Results: After exclusion of duplicates, 314 abstracts were reviewed; of these 25 papers were included from 6 different countries, with the median year of the study publication 2019. From the 25 papers, 26 patients were studied with an average patient age of 32.7 years with 42% male and 58% female. Between male and female there was no significant difference in age, type of CCB taken, or days on ECMO. Average time on ECMO was 4.3 days. Venoarterial and venovenous ECMO use were 92.3% and 7.7%, respectively. Survival to hospital discharge was 84.6%. Prior to ECMO cannulation, patients received up to six medical treatments for CCBOD, with the majority receiving four to five treatments (53.8%). There was no correlation between number of therapies and days on ECMO (r=0.092, P=0.684). Conclusion: Our systematic review demonstrates that ECMO is a newly used and possibly valuable therapy for CCBOD when medical treatment fails. Most patients received aggressive medical therapies and still were unstable enough to require ECMO. Survival to discharge after ECMO for CCBOD is substantially higher than standard VV or VA ECMO uses. While medical management is still the main therapy for CCBOD, our results show that a persistently unstable patient may benefit from prompt evaluation at an ECMO center for treatment.

Use of Veno-Arterial Extracorporeal Membrane Oxygenation as a Bridge to Transplantation

Use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a potential option to bridge critically unwell patients to heart transplantation. However, given the critically unwell nature of this patient cohort, morbidity and mortality are expectedly high, with previous literature reporting 30-day mortality of up to 30%. This study investigated the mortality of patients on preoperative VA-ECMO prior to heart transplantation in a single Australian centre.

Management of Multisystem Inflammatory Syndrome in Children: Decision-Making Regarding a New Condition in the Absence of Clinical Trial Data.

Multisystem inflammatory syndrome in children (MIS-C) is a new illness that evolved during the COVID-19 pandemic with initial reports of severe disease including use of extracorporeal membrane oxygenation and death. Institutions rapidly assembled task forces to develop treatment algorithms. At the national/international levels, collaboratives and associations assembled consensus writing groups to draft guidelines. These guidelines and algorithms were initially on the basis of expert opinion and small case series. Some groups used the Delphi approach, and the resultant guidelines often mimicked those for other conditions that resembled MIS-C, like Kawasaki disease (KD). For instance, intravenous immunoglobulin (IVIG), a known effective treatment for KD, was recommended for MIS-C. Early in the pandemic many favoured IVIG over steroids as first-line therapy. As evidence evolved so did some guidelines, which now endorse the dual use of IVIG with steroids as first-line therapy. In contrast, withholding immunotherapy became an option for some MIS-C patients with mild symptoms. Herein, we review guidelines and discuss the evidence informing early recommendations, how this has evolved, the role and limitations of expert opinion and observational data, and the importance of leveraging existing research infrastructures, such as the intensive care unit collaborative (Overcoming COVID-19 surveillance registry), and the International Kawasaki Disease Registry. Finally, we discuss strategies to rapidly develop, deploy, and adapt clinical trials evaluating the treatment of such rare conditions in children, which might include alternatives to conventional clinical trial design. The emergence of MIS-C during the COVID-19 pandemic has highlighted unmet needs regarding research of a new condition.

P94: Successful Extracorporeal Membrane Oxygenation Course in an Acquired Immune Deficiency Syndrome (AIDS) Patient with Acute Respiratory Distress Syndrome (ARDS) Complicated by Pneumocystis jirovecii Pneumonia and COVID-19: A Unique Case

Background: The use of extracorporeal membrane oxygenation (ECMO) in patients who have acute respiratory distress syndrome has been shown to have very good outcomes. However, there is limited data to support the initiation of ECMO in patients who have human immunodeficiency virus infection with or without acquired immune deficiency syndrome. We review the current literature and case reports of patients placed on Venous-Venous ECMO support for HIV and AIDS, with confection with Pneumocystis pneumonia and covid-19 pneumonia. Methods: We present a unique and challenging case of a 30 year old male, with no known past medical history, unvaccinated against covid-19, who presented with one week of progressive shortness of breath. On admission he was found with moderate bilateral infiltrates and was diagnosed with covid-19 pneumonia. Despite appropriate medical therapy, patient developed worsening hypoxic respiratory failure. Found to have elevated (1-3)-β-d-glucan and tested positive for HIV. CD4 count 11, HIV viral load 70,000. The patient remained severely hypoxemic despite mechanical ventilation, sedation, paralytics and proning. Venous venous extracorporeal membrane oxygenation was initiated. Considering his non improvement with variety of antivirals and antibiotics and with elevated (1-3)-β-d-glucan in the setting of AIDS he was treated for presumed Pneumocystis pneumonia. The patient tolerated proning while on VV ECMO and his course was complicated with bilateral pneumothorax necessitating chest tube placement. Results: The patient successfully completed 64 days on VV ECMO, where he was treated for PCP pneumonia, covid pneumonia, CMV viremia and tolerated initiation of anti-retroviral therapy. Patient was successfully decannulated, and ultimately discharged from the hospital. Conclusion: VV-ECMO can be a beneficial intervention with successful outcomes in severely immunocomprimised patients with AIDS. This case highlights the importance of minimizing sedation and early mobilization on ECMO support.Figure 1. CT Chest with contrast approximately 40 days on VV ECMO

Intensity at the end of life in pediatric neuro-oncology patients: The case for pediatric palliative care.

10021 Background: Although pediatric cancer is rare, it is the leading cause of death by disease after infancy for children and adolescents in the United States. Children exist in the context of a family; hence, excellent care for a child must also include attention to the needs of the family. Palliative care aims to enhance quality-of-life for these children living with life threatening illnesses and their families. Among pediatric cancers, brain tumors have high disease-related mortality rates; therefore, early introduction of palliative care to these patients is critical. This study aims to evaluate the association of palliative care during the terminal admissions of pediatric neuro-oncology patients and intensity of care provided at the end of life. Methods: Pediatric patients with brain tumors were identified using the Pediatric Health Information System (PHIS). Inclusion criteria were age &lt;18, diagnosis of brain tumor as defined by ICD-10 codes, discharged as deceased, and hospital admission between 1/1/2017 and 12/31/2021. Intensity of care measures included: pediatric intensive care unit (PICU) admission, mechanical ventilation, total parenteral nutrition (TPN), and extracorporeal membrane oxygenation (ECMO). Results: 567 patients met the inclusion criteria. 359/567 (63%) patients had an inpatient palliative care consultation during their terminal hospital stay. Patients receiving a palliative care consultation had a lower percentage of PICU admission (64.9 vs 83.2, p=&lt;0.001), mechanical ventilation use (51.0 vs 76.0, p=&lt;0.001), and TPN use (18.1 vs 25.5, p=0.027). There were no significant differences in length of stay (22.07 vs 22.25 days, p=0.181) and ECMO use (0.28% vs 1.92%, p=0.450). Conclusions: Pediatric patients receiving palliative care consultations during their terminal admission received less intense care while having comparable lengths of stay. Palliative care should be offered to all families, even with aggressive goals, to help incorporate quality of life and comfort in the treatment plan and to ensure bereavement support is available if needed. Similar to data in the adult palliative care literature, this data demonstrates reduced resource utilization among pediatric patients receiving palliative care. Palliative care has been shown to be a supportive service that has the potential to improve the quality of life of patients. The first step toward equitable healthcare is to ensure that all children with a potentially terminal cancer diagnosis have access to full supportive services, including palliative care.

Comparison of clinical outcomes with cangrelor plus aspirin versus oral dual antiplatelet therapy in patients supported with venoarterial extracorporeal membrane oxygenation.

Patients with refractory cardiogenic shock from an acute myocardial infarction may receive percutaneous coronary intervention (PCI) and require the use of venoarterial extracorporeal membrane oxygenation (VA-ECMO). The purpose of this study was to compare bleeding and thrombotic events in patients treated with cangrelor plus aspirin versus oral dual antiplatelet therapy (DAPT) while supported with VA-ECMO. We conducted a retrospective review of patients who received PCI, were supported with VA-ECMO, and were treated with either cangrelor plus aspirin or oral DAPT from February 2016 through May 2021 at Allegheny General Hospital. The primary objective was the incidence of major bleeding, defined as Bleeding Academic Research Consortium (BARC) type 3 or greater. The incidence of thrombotic events was a secondary objective. Thirty-seven patients were included, 19 in the cangrelor plus aspirin group, and 18 in the oral DAPT group. All the patients in the cangrelor group received a dose of 0.75 mcg/kg/min. Major bleeding occurred in 7 patients (36.8%) in the cangrelor group compared to 7 patients (38.9%) in the oral DAPT group (p = 0.90). No patient developed stent thrombosis. Two patients (10.5%) in the cangrelor group had a thrombotic event versus 3 patients (16.7%) in the oral DAPT group (p = 0.66). Bleeding and thrombotic events were comparable between patients receiving cangrelor plus aspirin versus oral DAPT while on VA-ECMO.

P71: Use of Veno-Arterial Extracorporeal Membrane Oxygenation and Impella for Cardiogenic Shock due to Cocaine Abuse

Background: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and Impella left ventricular assist device individually offer cardiovascular support for cardiogenic shock patients. Each modality has its own benefits and downfalls. We present a case in which a patient developed cocaine-induced coronary vasoconstriction resulting in cardiogenic shock with rapid systemic decompensation. We employed VA-ECMO and subsequent Impella to recover the patient. Methods: A 26-year-old male with a history of Graves’ Disease and chronic cocaine abuse presented to the ED with chest pain following cocaine ingestion. EKG showed sinus tachycardia and ST-elevations throughout, suspicious of coronary vasospasm. Labs showed an acute kidney injury as well as shock liver. Bedside echocardiogram (ECHO) revealed a severely depressed left ventricular ejection fraction (LVEF) of <10%. He was hemodynamically unstable for coronary catheterization and was emergently cannulated for VA-ECMO via the right femoral artery and left femoral vein. After we gained stability and slowly weaned the inotropic support. A follow-up ECHO revealed a dilated left ventricle and biventricular failure. With better hemodynamics, we did a catheterization showing coronary vasoconstriction, “clamping down” of distal vessels. (Figure 1) Due to the left ventricular dilation and its poor contractility, we decided to place an Impella. Results: The patient was supported on VA ECMO for 4 days, at which his LVEF recovered to 30-35%. The Impella device remained for an additional 3 days as his labs and hemodynamics improved. His LVEF at Impella removal was 40%. The patient was discharged in 14 days with a normal LVEF. Conclusion: One of the major downfalls of VA-ECMO is the lack of left ventricular unloading resulting in increased afterload and hindering recovery. An Impella can be used to help vent the left ventricle. This combination has been shown in several studies to improve outcomes in patients with acute coronary syndrome. The technique was employed with successful cardiac recovery in a patient who developed cardiogenic shock from coronary vasospasm from cocaine use.Figure 1. Coronary angiography showing coronary vasoconstriction due to cocaine use

Sustaining Life versus Altering Life-Saving Drugs: Insights to Explain the Paradoxical Effect of Extracorporeal Membrane Oxygenation on Drugs.

There has been a substantial increase in the use of extracorporeal membrane oxygenation (ECMO) support in critically ill adults. Understanding the complex changes that could affect drugs' pharmacokinetics (PK) and pharmacodynamics (PD) is of suitable need. Therefore, critically ill patients on ECMO represent a challenging clinical situation to manage pharmacotherapy. Thus, clinicians' ability to predict PK and PD alterations within this complex clinical context is fundamental to ensure further optimal and, sometimes, individualized therapeutic plans that balance clinical outcomes with the minimum drug adverse events. Although ECMO remains an irreplaceable extracorporeal technology, and despite the resurgence in its use for respiratory and cardiac failures, especially in the era of the COVID-19 pandemic, scarce data exist on both its effect on the most commonly used drugs and their relative management to achieve the best therapeutic outcomes. The goal of this review is to provide key information about some evidence-based PK alterations of the drugs used in an ECMO setting and their monitoring.

Use of Perioperative Extracorporeal Membranous Oxygenation in Pulmonary Endarterectomy Cases: A Systematic Review and Meta-Analysis.

Introduction: Pulmonary endarterectomy (PEA) is known to be a curative intervention for chronic thromboembolic pulmonary hypertension (CTEPH). Its complications include endobronchial bleeding, persistent pulmonary arterial hypertension, right ventricular failure, and reperfusion lung injury. Extracorporeal membranous oxygenation (ECMO) is a perioperative salvage method for PEA. Although risk factors and outcomes have been reported in several studies, overall trends remain unknown. We performed a systematic review and study-level meta-analysis to understand the outcomes of ECMO utilization in the perioperative period of PEA. Methods: We performed a literature search with PubMed and EMBASE on 11/18/2022. We included studies including patients who underwent perioperative ECMO in PEA. We collected data including baseline demographics, hemodynamic measurements, and outcomes such as mortality and weaning of ECMO and performed a study-level meta-analysis. Results: Eleven studies with 2632 patients were included in our review. ECMO insertion rate was 8.7% (225/2,625, 95% CI 5.9-12.5) in total, VV-ECMO was performed as the initial intervention in 1.1% (41/2,625, 95% CI 0.4-1.7) (Figure 3), and VA-ECMO was performed as an initial intervention in 7.1% (184/2,625, 95% CI 4.7-9.9). Preoperative hemodynamic measurements showed higher pulmonary vascular resistance, mean pulmonary arterial pressure, and lower cardiac output in the ECMO group. Mortality rates were 2.8% (32/1238, 95% CI: 1.7-4.5) in the non-ECMO group and 43.5% (115/225, 95% CI: 30.8-56.2) in the ECMO group. The proportion of patients with successful weaning of ECMO was 72.6% (111/188, 95% CI: 53.4-91.7). Regarding complications of ECMO, the incidence of bleeding and multi-organ failure were 12.2% (16/79, 95% CI: 13.0-34.8) and 16.5% (15/99, 95% CI: 9.1-28.1), respectively. Conclusion: Our systematic review showed a higher baseline cardiopulmonary risk in patients with perioperative ECMO in PEA, and its insertion rate was 8.7%. Further studies that compare the use of ECMO in high-risk patients who undergo PEA are anticipated.

Improving the Numbers, But Harming the Patient? The Authors Respond.

To the Editor: We thank da Costa et al.1 for their letter which makes some interesting observations. We agree that our study alone cannot be used to justify the use of extracorporeal membrane oxygenation (ECMO) as a strategy to protect the lungs in patients with moderate acute respiratory failure (ARF)—nor do we make a claim that it should. Severity of respiratory failure is not just defined by a single PaO2/FiO2 ratio value, but on a more complex clinical evaluation which must also take into account the duration of hypoxemia. We take this opportunity to stress that all patients in our study2 had ARF severe enough to receive ECMO based on the indications established by our national service. The “less severe” group had a median PaO2/FiO2 ratio of 105 mm Hg despite median FiO2 of 0.85, but fulfilled other criteria for ECMO. As this cohort was matched for PaCO2 with the “very severe” group, it is likely the price the patient has to pay for the PaO2/FiO2 ratio is injurious mechanical ventilation. Therefore, we would suggest that many of these patients would already meet criteria for ECMO in many systems, and that we are not advancing a “new” indication. There is now substantial evidence for the association between increased mechanical power, ventilator-induced lung injury and mortality in ARF,3 and in this context the use of ECMO allows the least damaging lung ventilation strategy4 and better outcomes.5 We would suggest, intuitively, that increased duration of high mechanical power to the lungs will thus increase mortality even if PaO2/FiO2 ratio is not yet “severe.” High mechanical power can—in the short term—increase PaO2/FiO2 masking the severity of disease, but ultimately increasing mortality. This was exactly what happened in the OSCILLATE Trial, where high-flow oscillatory ventilation resulted in better oxygenation but worse patient outcomes.6 The results of more recent studies are consistent with our findings: a large multinational cohort study of coronavirus patients suggested a survival benefit in those with PaO2/FiO2 ratio of 120–150 mm Hg.7 Da Costa et al. are correct also to identify the subset of ARF patients who experience acute right ventricular dysfunction, which is often exacerbated by “lung-protective” ventilation measures.8 Whether, or at what stage, such patients may benefit from ECMO support, is not a question our study can answer. The task then is how best to determine the answer to these questions? Do patients with “moderate-severe” respiratory failure benefit from ECMO? What about those with acute right ventricle (RV) dysfunction? Ultimately, we agree with da Costa et al. that in the absence of randomized controlled trials, the solution is in high-quality observational registries of ARF, not just of therapies such as ECMO, with advanced causal inference methods. For the individual patient, we suggest that the optimal strategy remains to identify the point at which the benefits of ECMO in preventing hypoxia and avoiding injurious lung ventilation outweigh its risks.

Tricuspid Regurgitation After Heart Transplantation: The Cause or the Result of Graft Dysfunction?

Tricuspid regurgitation (TR) is common following heart transplantation and has been shown to adversely influence patient outcomes. The aim of this study was to identify causes of progression to moderate-severe TR in the first 2 y after transplantation. This was a retrospective, single-center study of all patients who underwent heart transplantation over a 6-y period. Transthoracic echocardiogram (TTE) was performed at month 0, between 6 and 12 mo, and 1-2 y postoperatively to determine the presence and severity of TR. A total of 163 patients were included, of whom 142 underwent TTE before first endomyocardial biopsy. At month 0, 127 (78%) patients had nil-mild TR before first biopsy, whereas 36 (22%) had moderate-severe TR. In patients with nil-mild TR, 9 (7%) progressed to moderate-severe TR by 6 mo and 1 underwent tricuspid valve (TV) surgery. Of patients with moderate-severe TR before first biopsy, by 2 y, 3 had undergone TV surgery. The use of postoperative extracorporeal membrane oxygenation (ECMO) in the latter group was significant (78%; P < 0.05) as was rejection profile ( P = 0.02). Patients with late progressive moderate-severe TR had a significantly higher 2-y mortality than those who had moderate-severe TR immediately. Overall, our study has shown that in the 2 main groups of interest (early moderate-severe TR and progression from nil-mild to moderate-severe TR), TR is more likely to be the result of significant underling graft dysfunction rather than the cause of it.

Predictors and Hospital Outcomes in Pregnant Patients Undergoing Extracorporeal Membrane Oxygenation: A Nationwide Study

(Anesth Analg. 2022;135:1172–1179) Extracorporeal membrane oxygenation (ECMO) use, advanced cardiorespiratory support for patients with decreased cardiac or respiratory function, has been on the rise. ECMO for pregnant women has also become more common, however, studies on ECMO often lack inclusion of parturients. Given a lack of information regarding appropriate timing and indications for ECMO for pregnant women, this study seeks to identify in-hospital mortality and morbidity rates for parturients who underwent ECMO.

Cardiovascular Complications Related to the Use of ECMO in Cardiac Surgery

ECMO (Extracorporeal Membrane Oxygenation) is an extracorporeal oxygenation technique that involves the use of a specialized membrane to oxygenate the blood and remove carbon dioxide out of the body. It is commonly used in critically ill patients with severe respiratory or cardiac failure to provide life support while waiting for organs to recover normal function.1

P290 EXTRACORPOREAL MEMBRANE OXYGENATION SYSTEM AS A BRIDGE TO REPARATIVE SURGERY IN VENTRICULAR SEPTAL DEFECT COMPLICATING ACUTE MYOCARDIAL INFARCTION

Abstract Introduction Post–infarct ventricular septal defect (VSD) is a life tethering complication of acute myocardial infarction which is associated to high in–hospital mortality (90–95%). The optimal peri–operative management including timing of surgical correction is still debated. There is a large body of evidence demonstrating that surgical repair is also associated to poor post–operative outcomes due to cardiogenic shock and multiorgan failure (MOF). The use of extracorporeal membrane oxygenation (ECMO) system in adult cardiac surgery is not routine, occurring in a minority of critically ill patients, typically postoperatively. Here we present our single centre experience of patients with post–infarct VSD managed preoperatively with ECMO support as a bridge to definitive surgical closure. Materials and methods Between February 2020 to July 2021, 5 patients presented to our unit with diagnosis of post–infarct VSD and were managed with preoperative veno–arterial (V–A) ECMO implantation and enrolled in our study. Clinical parameters (such as mean arterial pressure, central venous pressure, ECG, pulmonary artery pressure), blood tests, trans–thoracic and trans–esophageal echocardiography, chest X–rays have been evaluated both before and after surgery. Primary end–point was all causes in–hospital mortality. Results Three (60%) patients were male and mean age was 70,4 (60–78) years. All patients underwent surgical repair. ECMO was positioned between 1 and 9 days prior to surgical correction, giving the chance to reduce the pharmacological inotropic support while still reverting the MOF as demonstrated by the reduction of AST, ALT, bilirubin level, decreased CVP and systemic lactate levels. Two (40%) patients were successfully weaned off from the mechanical support and discharged home in good clinical conditions. Two (40%) patients developed MOF after surgery leading to the exitus. Conclusions We postulate that the use of V–A use preoperatively in patients with cardiogenic shock secondary to post–infarct VSD is appropriate and where feasible should be considered. It allows restoration of haemodynamic stability and resolution of MOF. This provides for a delayed surgical repair with a likely higher chance of operative success and reduced 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.