Single-institution experience of extracorporeal membrane oxygenation for near-fatal asthma

Near-fatal asthma (NFA) is the most severe presentation of asthma. It is characterized by hypoxemic and hypercapnic respiratory failure requiring ventilatory assistance, including non-invasive ventilation and mechanical ventilation. However, NFA has a high mortality rate despite conventional therapy. Extracorporeal membrane oxygenation (ECMO) is a treatment modality that is increasingly being utilized as rescue therapy in patients with NFA that is refractory to mechanical ventilation. Prior analyses of the international Extracorporeal Life Support Organization (ELSO) registry data showed a survival rate of over 83% in patients placed on venovenous (VV) ECMO for NFA, but with notable rate of hemorrhagic complications. We report seven cases of adults with NFA requiring ECMO support at our large quaternary care institution between the years 2019 and 2022. All seven patients presented with respiratory failure in the setting of asthma exacerbation that progressed despite standard pharmacotherapy and mechanical ventilation. All patients survived to hospital discharge after ECMO support without hemorrhagic complications, highlighting the effectiveness and safety of ECMO when appropriately used in this population.

Ability of the respiratory ECMO survival prediction (RESP) score to predict survival for patients with COVID-19 ARDS and non-COVID-19 ARDS: a single-center retrospective study

The respiratory ECMO survival prediction (RESP) score is used to predict survival for patients managed with extracorporeal membrane oxygenation (ECMO), but its performance in patients with Coronavirus Disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS) is unclear. We evaluated the ability of the RESP score to predict survival for patients with both non-COVID 19 ARDS and COVID-19 ARDS managed with ECMO at our institution. Receiver operating characteristic area under the curve (AUC) analysis found the RESP score reasonably predicted survival in patients with non-COVID-19 ARDS (AUC 0.76, 95% CI 0.68-0.83), but not patients with COVID-19 ARDS (AUC 0.54, 95% CI 0.41-0.66).

Neonatal venoarterial and venovenous ECMO

ECMO remains an important support tool in the treatment of neonates with reversible congenital cardiopulmonary diseases. There are specific circumstances that call for either venoarterial (VA) or venovenous (VV) ECMO in neonates. While limited by the infant's the size and gestational age, ECMO can confer exceptional survival rates to a number of neonates who can often develop without devastating complications. However, it remains a labor and time intensive endeavor, which may be impractical or unattainable in resource-limited environments. While adult and pediatric ECMO indications and equipment options have expanded in recent years, neonatal ECMO continues to be a niche subspecialty requiring specific expertise and technical skill, especially considering the ever-changing neonatal physiology in the setting of cardiopulmonary support. It is critical to recognize the unique approaches to cannulation options, imaging, vessel management, anticoagulation, and monitoring protocols to achieve optimal outcomes. Thus, it becomes nearly impossible to separate the role of pediatric surgeons from the continuous involvement with and management of neonatal ECMO patients. This necessitates that pediatric surgeons in ECMO centers continue to hone their expertise and remain heavily involved in neonatal ECMO. This section reviews the most critical current approaches and unresolved controversies in neonatal ECMO with special attention to the practical aspects and decisions a surgeon faces in initiation and termination of neonatal ECMO.

Evolving outcomes of extracorporeal membrane oxygenation support for severe COVID-19 ARDS in Sorbonne hospitals, Paris

Background

Extracorporeal membrane oxygenation (ECMO) was frequently used to treat patients with severe coronavirus disease-2019 (COVID-19)-associated acute respiratory distress (ARDS) during the initial outbreak. Care of COVID-19 patients evolved markedly during the second part of 2020. Our objective was to compare the characteristics and outcomes of patients who received ECMO for severe COVID-19 ARDS before or after July 1, 2020.

Methods

We included consecutive adults diagnosed with COVID-19 in Paris–Sorbonne University Hospital Network ICUs, who received ECMO for severe ARDS until January 28, 2021. Characteristics and survival probabilities over time were estimated during the first and second waves. Pre-ECMO risk factors predicting 90-day mortality were assessed using multivariate Cox regression.

Results

Characteristics of the 88 and 71 patients admitted, respectively, before and after July 1, 2020, were comparable except for older age, more frequent use of dexamethasone (18% vs. 82%), high-flow nasal oxygenation (19% vs. 82%) and/or non-invasive ventilation (7% vs. 37%) after July 1. Respective estimated probabilities (95% confidence intervals) of 90-day mortality were 36% (27–47%) and 48% (37–60%) during the first and the second periods. After adjusting for confounders, probability of 90-day mortality was significantly higher for patients treated after July 1 (HR 2.27, 95% CI 1.02–5.07). ECMO-related complications did not differ between study periods.

Conclusions

90-day mortality of ECMO-supported COVID-19–ARDS patients increased significantly after July 1, 2020, and was no longer comparable to that of non-COVID ECMO-treated patients. Failure of prolonged non-invasive oxygenation strategies before intubation and increased lung damage may partly explain this outcome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03780-6.

Early initiation of awake venovenous extracorporeal membrane oxygenation (ECMO) in critical COVID-19 pneumonia: A case reports

Introduction

Overall, patients with Sars-cov-2 disease treated with mechanical ventilation, which is not the case in our study. This report presents our first successful experience of awake ECMO application in a critical patient with hypoxemic Respiratory Failure related to COVID-19 infection in Morocco.

Case management

We have reported a 52-year-old female patient who was diagnosed with COVID-19 infection and progressed to critical cases. She was a candidate for applying awake extracorporeal membrane oxygenation (ECMO) in the absence of invasive mechanical ventilation, under local anesthesia alone with good progress and ventilatory weaning.

Conclusion

This therapeutic attitude can be beneficial for certain critical and severe cases due to COVID-19 infection. Each ECMO program should develop goals, methods, protocols, and best practices while adapting appropriately to the personnel and equipment available.

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Extracorporeal membrane oxygenation (ECMO) is extracorporeal life support used as salvage therapies in patients with acute cardiac, pulmonary or cardiopulmonary failure.

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Early initiation of awake venovenous extracorporeal membrane oxygenation (ECMO) in critical cases of COVID-19 infection.

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“Awake ECMO” support in patients with COVID-19 is feasible and has benefits in the absence of mechanical ventilation.

A mathematical model of CO2, O2 and N2 exchange during venovenous extracorporeal membrane oxygenation

Background

Venovenous extracorporeal membrane oxygenation (vv-ECMO) is an effective treatment for severe respiratory failure. The interaction between the cardiorespiratory system and the oxygenator can be explored with mathematical models. Understanding the physiology will help the clinician optimise therapy. As others have examined O₂ exchange, the main focus of this study was on CO₂ exchange.

Methods

A model of the cardiorespiratory system during vv-ECMO was developed, incorporating O₂, CO₂ and N₂ exchange in both the lung and the oxygenator. We modelled lungs with shunt fractions varying from 0 to 1, covering the plausible range from normal lung to severe acute respiratory distress syndrome. The effects on P_aCO₂ of varying the input parameters for the cardiorespiratory system and for the oxygenator were examined.

Results

P_aCO₂ increased as the shunt fraction in the lung and metabolic CO₂ production rose. Changes in haemoglobin and F_IO₂ had minimal effect on P_aCO₂. The effect of cardiac output on P_aCO₂ was variable, depending on the shunt fraction in the lung.

P_aCO₂ decreased as extracorporeal circuit blood flow was increased, but the changes were relatively small in the range used clinically for vv-ECMO of > 2 l/min. P_aCO₂ decreased as gas flow to the oxygenator rose and increased with recirculation. The oxygen fraction of gas flow to the oxygenator had minimal effect on P_aCO₂.

Conclusions

This mathematical model of gas exchange during vv-ECMO found that the main determinants of P_aCO₂ during vv-ECMO were pulmonary shunt fraction, metabolic CO₂ production, gas flow to the oxygenator and extracorporeal circuit recirculation.

Electronic supplementary material

The online version of this article (10.1186/s40635-018-0183-4) contains supplementary material, which is available to authorized users.