ECMO in COVID-19-prolonged therapy needed? A retrospective analysis of outcome and prognostic factors

Prevalence and Survival of Prolonged Venovenous Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome: An Analysis of the Extracorporeal Life Support Organization Registry

OBJECTIVES

To examine trends in utilization and outcomes among patients with the acute respiratory distress syndrome (ARDS) requiring prolonged venovenous extracorporeal membrane oxygenation (VV ECMO) support.

DESIGN

Retrospective observational cohort study.

SETTING

Adult patients in the Extracorporeal Life Support Organization registry.

PATIENTS

Thirteen thousand six hundred eighty-one patients that required ECMO for the support of ARDS between January 2012 and December 2022.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Mortality while supported with VV ECMO and survival to hospital discharge based on ECMO duration were examined utilizing multivariable logistic regression. Among the 13,681 patients supported with VV ECMO, 4,040 (29.5%) were supported for greater than or equal to 21 days and 975 (7.1%) for greater than or equal to 50 days. Patients supported with prolonged VV ECMO were less likely to be discharged alive from the hospital compared with those with short duration of support (46.5% vs. 59.7%; p < 0.001). However, among patients supported with VV ECMO greater than or equal to 21 days, duration of extracorporeal life support was not significantly associated with mortality (odds ratio [OR], 0.99; 95% CI, 0.98-1.01; p = 0.87 and adjusted OR, 0.99; 95% CI, 0.97-1.02; p = 0.48). Even in those supported with VV ECMO for at least 120 days (n = 113), 52 (46.0%) of these patients were ultimately discharged alive from the hospital.

CONCLUSIONS

Prolonged VV ECMO support of ARDS has increased and accounts for a substantial portion of cases. Among patients that survive for greater than or equal to 21 days while receiving VV ECMO support, duration is not predictive of survival to hospital discharge and clinical recovery may occur even after very prolonged VV ECMO support.

[COVID-19 in the intensive care unit]

The acute respiratory failure as well as ARDS (acute respiratory distress syndrome) have challenged clinicians since the initial description over 50 years ago. Various causes can lead to ARDS and therapeutic approaches for ARDS/ARF are limited to the support or replacement of organ functions and the prevention of therapy-induced consequences. In recent years, triggered by the SARS-CoV-2 pathogen, numerous cases of acute lung failure (C-ARDS) have emerged. The pathophysiological processes of classical ARDS and C-ARDS are essentially similar. In their final stages of inflammation, both lead to a disruption of the blood-air barrier. Treatment strategies for C-ARDS, like classical ARDS, focus on supporting or replacing organ functions and preventing consequential damage. This article summarizes the treatment strategies in the intensive care unit.

The Role of Palliative Care Consultation in Withdrawal of Life-Sustaining Treatment among ICU Patients Receiving Veno-Venous Extracorporeal Membrane Oxygenation (VV-ECMO): A Retrospective Case-Control Study

Background: Extracorporeal membrane oxygenation (ECMO) has extended the survivability of critically ill patients beyond their unsupported prognosis and has widened the timeframe for making an informed decision about the goal of care. However, an extended time window for survival does not necessarily translate into a better outcome and the sustaining treatment is ultimately withdrawn in many patients. Emerging evidence has implicated the determining role of palliative care consult (PCC) in direction of the care that critically ill patients receive. Objective: To evaluate the impact of PCC in withdrawal of life-sustaining treatment (WOLST) among critically ill patients, who were placed on venovenous ECMO (VV-ECMO) at the intensive care unit (ICU) of a tertiary care hospital. Methods: In a retrospective observational study, electronic medical records of 750 patients admitted to the ICU of our hospital between January 1, 2015, and October 31, 2021, were reviewed. Data was collected for patients on VV-ECMO, for whom WOLST was withdrawn during the ICU stay. Clinical characteristics and the underlying reasons for WOLST were compared between those who received PCC (PCC group) and those who did not (non-PCC group). Results: A total of 95 patients were included in our analysis, 63 in the PCC group and 32 in the non-PCC group. The average age of the study population was 48.8 ± 12.6 years, and 64.2% were male. There was no statistically significant difference between the two groups in terms of demographics or clinical characteristics at the time of ICU admission. The average duration of ICU stay and VV-ECMO were 14.1 ± 19.9 days and 9.4 ± 16.6 days, respectively. The number of PCC visits was correlated with the length of ICU stay. The average duration of ICU stay (40.3 ± 33.2 days vs 27.8 ± 19.3 days, P = .05) and ECMO treatment (31.9 ± 27 days vs 18.6 ± 16.1 days, P = .01) were significantly longer in patients receiving PCC than those not receiving PCC. However, the frequency of life sustaining measures or the underlying reasons for WOLST did not significantly differ between the two groups (P > .05). Conclusion: Among ICU patients requiring ECMO support, longer duration of ICU stay and treatment with a higher number of life-sustaining measures seemed to be correlated with the number of PCC visits. The underlying reasons for WOLST seem not to be affected by PCC.

Relationship between the Pre-ECMO and ECMO Time and Survival of Severe COVID-19 Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is the etiology of acute respiratory distress syndrome (ARDS). Extracorporeal membrane oxygenation (ECMO) is used to support gas exchange in patients who have failed conventional mechanical ventilation. However, there is no clear consensus on the timing of ECMO use in severe COVID-19 patients.

OBJECTIVE

The aim of this study is to compare the differences in pre-ECMO time and ECMO duration between COVID-19 survivors and non-survivors and to explore the association between them.

METHODS

PubMed, the Cochrane Library, Embase, and other sources were searched until 21 October 2022. Studies reporting the relationship between ECMO-related time and COVID-19 survival were included. All available data were pooled using random-effects methods. Linear regression analysis was used to determine the correlation between pre-ECMO time and ECMO duration. The meta-analysis was registered with PROSPERO under registration number CRD42023403236.

RESULTS

Out of the initial 2473 citations, we analyzed 318 full-text articles, and 54 studies were included, involving 13,691 patients. There were significant differences between survivors and non-survivors in the time from COVID-19 diagnosis (standardized mean difference (SMD) = -0.41, 95% confidence interval (CI): [-0.53, -0.29], p < 0.00001), hospital (SMD = -0.53, 95% CI: [-0.97, -0.09], p = 0.02) and intensive care unit (ICU) admission (SMD = -0.28, 95% CI: [-0.49, -0.08], p = 0.007), intubation or mechanical ventilation to ECMO (SMD = -0.21, 95% CI: [-0.32, -0.09], p = 0.0003) and ECMO duration (SMD = -0.18, 95% CI: [-0.30, -0.06], p = 0.003). There was no statistical association between a longer time from symptom onset to ECMO (hazard ratio (HR) = 1.05, 95% CI: [0.99, 1.12], p = 0.11) or time from intubation or mechanical ventilation (MV) and the risk of mortality (highest vs. lowest time groups odds ratio (OR) = 1.18, 95% CI: [0.78, 1.78], p = 0.42; per one-day increase OR = 1.14, 95% CI: [0.86, 1.52], p = 0.36; HR = 0.99, 95% CI: [0.95, 1.02], p = 0.39). There was no linear relationship between pre-ECMO time and ECMO duration.

CONCLUSION

There are differences in pre-ECMO time between COVID-19 survivors and non-survivors, and there is insufficient evidence to conclude that longer pre-ECMO time is responsible for reduced survival in COVID-19 patients. ECMO duration differed between survivors and non-survivors, and the timing of pre-ECMO does not have an impact on ECMO duration. Further studies are needed to explore the association between pre-ECMO and ECMO time in the survival of COVID-19 patients.

"Death as the One Great Certainty": ethical implications of children with irreversible cardiorespiratory failure and dependence on extracorporeal membrane oxygenation

Introduction

Advances in medical technology have led to both clinical and philosophical challenges in defining death. Highly publicized cases have occurred when families or communities challenge a determination of death by the irreversible cessation of neurologic function (brain death). Parallels can be drawn in cases where an irreversible cessation of cardiopulmonary function exists, in which cases patients are supported by extracorporeal cardiopulmonary support, such as extracorporeal membrane oxygenation (ECMO).

Analysis

Two cases and an ethical analysis are presented which compare and contrast contested neurologic determinations of death and refusal to accept the irreversibility of an imminent death by cardiopulmonary standards. Ambiguities in the Uniform Determination of Death Act are highlighted, as it can be clear, when supported by ECMO, that a patient could have suffered the irreversible cessation of cardiopulmonary function yet still be alive (e.g., responsive and interactive). Parallel challenges with communication with families around the limits of medical technology are discussed.

Discussion

Cases that lead to conflict around the removal of technology considered not clinically beneficial are likely to increase. Reframing our goals when death is inevitable is important for both families and the medical team. Building relationships and trust between all parties will help families and teams navigate these situations. All parties may require support for moral distress. Suggested approaches are discussed.

Predictors of poor outcome in critically ill patients with COVID-19 pneumonia treated with extracorporeal membrane oxygenation

INTRODUCTION

We aimed to identify risk factors associated with ICU mortality in critically ill patients with COVID-19 pneumonia treated with Extracorporeal membrane oxygenation (ECMO). We also aimed to assess protocol violations of the local eligibility criteria of ECMO initiation.

METHODS

All 31 consecutive adult patients with confirmed COVID-19 pneumonia admitted to ICU and treated with ECMO from March 13th 2020 to 8 December 2021 were enrolled. Eligibility criteria for ECMO initiation were: P/F-ratio<50 mmHg >3 hours, P/F-ratio<80 mmHg >6 hours or pH<7.25 + PaCO2>60 mmHg >6 hours, despite maximal protective invasive ventilation. Primary outcome was ICU mortality. Univariate logistic regression analyses were performed to identify predictors of ICU mortality.

RESULTS

12 out of 31 patients (38.7%) did not survive ECMO treatment in ICU. Half of the non-survivors suffered from acute kidney failure compared to 3 out of 19 survivors (15.79%) (p = .04). Half of the non-survivors required CRRT treatment versus 1 patient in the survivor group (5.3%) (p < .01). Higher age (2.45 (0.97-6.18), p = .05), the development of AKI (5.33 (1.00-28.43), p = .05), need of CRRT during ICU stay (18.00 (1.79-181.31), p = .01) and major bleeding during ECMO therapy (0.51 (0.19-0.89), p < .01) were identified to be predictors of ICU mortality.

CONCLUSION

Almost 60% of patients could be treated successfully with ECMO with sustained results at 3 months. Predictors for ICU mortality were development of AKI and need of CRRT during ICU stay, higher age category and major bleeding. Inadvertent ECMO allocation was noted in almost one in five patients.

Outcomes of COVID-19 patients undergoing extracorporeal membrane oxygenation: A systematic review and meta-Analysis

BACKGROUND

The Coronavirus Disease 2019 (COVID-19) pandemic has been ongoing for over 3 years, during which numerous clinical and experimental studies have been conducted. The objective of this systematic review and meta-analysis was to assess the survival probability and complications of COVID-19 patients receiving extracorporeal membrane oxygenation (ECMO).

METHODS

We searched the databases by using Population-Intervention-Comparison-Outcome-Study Design (PICOS). We conducted a search of the PubMed, Web of Science, and EMBASE databases to retrieve studies published until December 10, 2022. A random-effects meta-analysis, subgroup analysis, and assessed the studies using the Newcastle-Ottawa Scale score. The results were presented as pooled morbidity with 95% confidence intervals.

RESULTS

The study was conducted on 19 studies that enrolled a total of 1494 patients, and the results showed a pooled survival probability of 66.0%. The pooled morbidity for intracranial hemorrhage was 8.7%, intracranial thrombosis 7.0%, pneumothorax 9.0%, pulmonary embolism 11.0%, pulmonary hemorrhage 9.0%, heart failure 14.0%, liver failure 13.0%, renal injury 44.0%, gastrointestinal hemorrhage 6.0%, gastrointestinal ischemia 6.0% and venous thrombosis 31.0%.

CONCLUSION

This systematic review and meta-analysis of observational studies focused on the survival probability and complications of COVID-19 patients undergoing ECMO, which are significant in evaluating the use of ECMO in COVID-19 patients and provide a basis for further research.

TRIAL REGISTRATION

Our study was registered on PROSPERO with registration number CRD42022382555.

Long-term venovenous extracorporeal membrane oxygenation support for acute respiratory distress syndrome after COVID-19

INTRODUCTION

Acute respiratory syndrome (ARDS) following coronavirus 2 (SARS-CoV-2) infection is a serious complication often causing irreversible lung injury associated with high mortality. Extracorporeal membrane oxygenation (ECMO) may be initiated in severe cases. We present a case of ARDS following SARS-CoV-2 infection with prolonged duration ECMO (1045 hours, 44 days) without exchanging circuit throughout the whole duration without technical complication.

CASE REPORT

A 71-year-old man of acute respiratory failure secondary to SARS-CoV-2 infection was initiated on venovenous ECMO (VV-ECMO). There was no technical complication without exchanging circuit throughout the whole prolonged ECMO duration (1045 hours, 44 days). Despite a great effort to improve his lung mechanics and gas exchange, there was continued clinical and physiological deterioration unfortunately. Following family discussion and with input from the multidisciplinary team (MDT) including palliative care specialists, there was recognition of deterioration despite optimal respiratory support. Shortly thereafter planned withdrawal occurred, and the patient passed away with his family at his bedside.

DISCUSSION

This case study illustrates that it may be considered to use long term ECMO as a bridge to recovery or lung transplantation of ARDS patient after SARS-CoV-2 infection with severe lung injury. Benefits from proper long-term ECMO management,it is possible of sparing to exchange circuit throughout the whole prolonged duration without technical complication.

CONCLUSION

This case indicates the feasibility of using of a long term VV-ECMO as a bridge to recovery or lung transplantation of ARDS patient after secondary to coronavirus 2 (SARS-CoV-2) infection with severe lung injury without circuit exchange. The optimal duration of VV-ECMO support and optimal diagnostic modalities for critical assessment of native lung recovery or irretrievable severe lung injury still require further investigation.

Outcomes of patients with COVID-19 supported by venovenous extracorporeal membrane oxygenation for greater than 90 days

Objective

To determine the characteristics and outcomes of patients requiring prolonged (>90 days) venovenous extracorporeal membrane oxygenation (VV ECMO) support for refractory Coronavirus disease 2019 (COVID-19)-associated respiratory failure.

Methods

A retrospective, observational analysis of consecutive patients requiring VV ECMO for COVID-19-associated respiratory failure was performed at a single institution between March 2020 and January 2022. Data were collected from the medical records. Patients were predominantly cannulated and supported long-term with a single, dual-lumen cannula in the internal jugular vein with the tip positioned in the pulmonary artery. All patients were managed with an awake VV ECMO approach, emphasizing avoidance of sedatives, extubation, ambulation, physical therapy, and nutrition. Patients requiring >90 days of ECMO were identified, analyzed, and compared to those needing a shorter duration of support.

Results

A total of 44 patients were supported on VV ECMO during the study period, of whom 36 (82%) survived to discharge. Thirty-one patients were supported for <90 days, of whom 28 (90%) were discharged alive. Thirteen patients required >90 days of ECMO. All patients were extubated. Eight patients (62%) survived to discharge, with 1 patient requiring lung transplantation prior to decannulation. All survivors were free from mechanical ventilation and alive at a 6-month follow-up. Of the 4 patients who died on prolonged ECMO, 2 developed hemothorax necessitating surgery and 2 succumbed to fatal intracranial hemorrhage.

Conclusions

Patients treated with VV ECMO for COVID-19-associated respiratory failure may require prolonged support to recover. Extubation, ambulation, aggressive rehabilitation, and nutritional support while on ECMO can yield favorable outcomes.

Outcomes associated with prolonged ECMO in COVID-19 associated ARDS: A single center experience

PURPOSE OF STUDY

The COVID-19 pandemic has led to a significant increase in the use of veno-venous extracorporeal membrane oxygenation (V-V ECMO) as a bridge to transplantation versus recovery. Unlike other etiologies of acute respiratory distress syndrome (ARDS), utilization of V-V ECMO in COVID-19 has been associated with longer duration of ECMO support requirements. Our team sought to evaluate outcomes associated with prolonged duration of ECMO support in this patient population.

METHODS

Single-center retrospective review of patients who were placed on ECMO due to COVID-19 associated ARDS. Specifically examining outcomes-transplant free survival, mortality and discharge rates-of patients requiring V-V ECMO support for greater than 50 days.

RESULTS

The median age of the cohort was 48 years and 13 patients (72%) were males. The median duration of ECMO support was 84 days (IQR 55-106). 11 patients (61%) had right ventricular dysfunction and 13 patients (72%) had pneumothoraces. There was a 33% percent (n = 6) mortality rate within cohort. One patient continues to require ECMO support at time of abstract submission. 11 patients (61%) patients were discharged, of which 3 patients required a lung transplant.

SUMMARY

Prolonged V-V ECMO can be associated with comparable outcomes to conventional V-V ECMO runs that are relatively shorter in duration. With availability of device and staffing, prolonged ECMO runs can potentially be justified in a highly selected patient population.

Prolonged VV ECMO: Navigating the Unchartered Sea

How to cite this article: Kumar V. Prolonged VV ECMO: Navigating the Unchartered Sea. Indian J Crit Care Med 2023;27(11):779-781.

Risk Factors for Bleeding in Coronavirus Disease 2019 Patients on Extracorporeal Membrane Oxygenation and Effects of Transcatheter Arterial Embolization for Hemostasis

Purpose

To evaluate risk factors for bleeding events in coronavirus disease 2019 (COVID-19) patients on extracorporeal membrane oxygenation (ECMO) and to share the initial results of transcatheter arterial embolization (TAE) for hemostasis.

Material and Methods

Forty-three COVID-19 patients who received ECMO from May 2020 to September 2021 were enrolled in this study. Patients with sudden onset anemia immediately underwent computed tomography to assess bleeding. We compared laboratory data, duration of ECMO, hospitalization period, and fatality of patients' groups with and without significant hemorrhagic events using the chi-square test and Mann-Whitney U test. We also assessed the results of TAE in patients who received hemostasis.

Results

A total of 25 bleeding events occurred in 24 of the 43 patients. Age was a risk factor for bleeding events and fatality. The average duration of ECMO and hospitalization period were significantly longer in those with bleeding events (42.9 and 54.3 days) than in those without bleeding events (16.2 and 25.0 days) (p < 0.05). In addition, those with bleeding had higher fatality (45.8%) than those without (15.8%) (p < 0.05). Active extravasation was confirmed for 5 events in 4 of 24 patients. TAE was attempted and performed successfully in all but one of these four cases, in whom bleeding ceased spontaneously.

Conclusions

Elderly COVID-19 patients on ECMO had a greater risk of bleeding complications and fatal outcomes. TAE was effective in providing prompt hemostasis for patients who have the treatment indication.

COVID-19 versus Other Disease Etiologies as the Cause of ARDS in Patients Necessitating Venovenous Extracorporeal Membrane Oxygenation-A Comparison of Patients' Data during the Three Years of the COVID-19 Pandemic

Considering the characteristics of coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS), we compared the clinical course and outcomes of patients with ARDS who received venovenous extracorporeal membrane oxygenation (VV ECMO) based on the etiology of ARDS. This retrospective single-center study included adult patients with severe ARDS necessitating VV ECMO during the COVID-19 pandemic. Among 45 patients who received VV ECMO, 21 presented with COVID-19. COVID-19 patients exhibited lower sequential organ failure assessment scores (9 [8-12.75] versus 8 [4-11.5], p = 0.033) but longer duration of VV ECMO support (10.5 days [3.25-29.25] versus 28 days [10.5-70.5] p = 0.018), which was accompanied by an weaning off rate from VV ECMO in 12/24 (50%) versus 12/21 (57.1%) and 28-day mortality in 9/24 [37.5%] versus 2/21 [9.5%] in non-COVID-19 and COVID-19 patients (p = 0.767, p = 0.040), respectively. Finally, in the adjusted Cox regression model for hospital mortality, the hazard ratio of COVID-19 was not significant (hazard ratio 0.350, 95% confidence interval 0.110-1.115, p = 0.076). Although the VV ECMO period was longer, COVID-19 did not significantly impact ECMO weaning off and mortality rates. Nonetheless, judicious patient selections based on risk factors should be followed.

Bleeding Complications in COVID-19 Critically Ill ARDS Patients Receiving VV-ECMO Therapy

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) therapy is rapidly expanding worldwide, yet this therapy has a serious risk of bleeding. Whether coagulation-activating viral infections such as COVID-19 may have an impact on the risk of bleeding is largely unknown. This study conducted a monocentric investigation of severely affected COVID-19 patients receiving VV-ECMO therapy with regard to the occurrence and possible influences of minor and major bleeding and transfusion requirements. Among the 114 included study patients, we were able to assess more than 74,000 h of VV-ECMO therapy. In these, 103 major bleeding events and 2283 minor bleeding events were detected. In total, 1396 red blood concentrates (RBCs) were administered. A statistically significant correlation with the applied anticoagulation or demographic data of the patients was not observed. Contrary to the frequently observed thromboembolic complications among COVID-19 patients, patients with VV-ECMO therapy, even under low-dose anticoagulation, show a distinct bleeding profile, especially of minor bleeding, with a substantial need for blood transfusions. COVID-19 patients show a tendency to have frequent bleeding and require repeated RBC transfusions during VV-ECMO. This fact might not be solely explained by the mechanical alteration of ECMO or anticoagulation.

Venovenous extracorporeal membrane oxygenation for coronavirus disease 2019 patients: A systematic review and meta-analysis

OBJECTIVE

Although the application of venovenous extracorporeal membrane oxygenation (VV-ECMO) in coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome (ARDS) is accumulating, the feasibility and safety of this therapy remain controversial. We aimed to evaluate the effect of VV-ECMO in the treatment of these patients.

METHODS

A comprehensive literature search was performed using PubMed, Embase, the Cochrane Library, and International Clinical Trials Registry Platform databases through November 2021. According to the inclusion and exclusion criteria, the included studies were screened, and meta-analysis was performed by R software (version 4.0.2).

RESULTS

Forty-two studies including 2037 COVID-19 patients supported with VV-ECMO due to ARDS were identified. The pooled analysis revealed that 30-, 60-, and 90-day mortality among patients were respectively 46% (95% CI 37%-57%, I2 = 66%), 46% (95% CI 30%-70%, I2 = 93%), and 49% (95% CI 43%-58%, I2 = 52%), and the pooled incidence rate of in-hospital mortality, major bleeding, hemorrhagic stroke, thrombosis, pulmonary embolism, deep venous thrombosis, and renal replacement therapy were respectively 35%, 39%, 11%, 40%, 15%, 21%, and 44%.

CONCLUSION

Although COVID-19 patients may have a higher risk of bleeding, hemorrhagic stroke, and acute kidney injury during ECMO therapy, the survival rate was more than half of the cases. Our data may support the application of VV-ECMO in COVID-19 patients.

Neutrophil-to-Lymphocyte Ratio as a Predictor of Mortality for COVID-19-Related Acute Respiratory Distress Syndrome (ARDS) Patients Requiring Extracorporeal Membrane Oxygenation Therapy

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) has been studied as an indicator of systemic inflammation and as a prognostic tool in multiple areas of medicine. Previous research has suggested that higher NLR and rapid increase to peak NLR are associated with poorer outcomes in patients with coronavirus disease 2019 (COVID-19), particularly in those experiencing acute respiratory distress syndrome (ARDS). Within vascular surgery, there is data to suggest a positive correlation between elevated pre-extracorporeal membrane oxygenation (ECMO) NLR and higher rates of mortality following major procedures. This study explores the prognostic value of peri-ECMO NLR in patients requiring veno-venous ECMO (VV-ECMO) therapy for COVID-19-related ARDS. The objective of this study was to explore the utility of pre-ECMO NLR as an easily accessible prognostic factor for patients suffering from COVID-19-associated ARDS that require VV-ECMO.

METHODS

This was a retrospective cohort study within a tertiary care hospital conducted between April 2020 and January 2021. Patients requiring VV-ECMO therapy for COVID-19-associated ARDS were included. Peri-ECMO NLR values, length of stay (LOS), duration on VV-ECMO, and discharge status were recorded. Receiver operating characteristic (ROC) curve analysis and Youden's J statistics were performed to calculate a cut-off value of 11.005 for pre-ECMO NLR and 17.616 for on-ECMO NLR. Pre-ECMO and on-ECMO Kaplan-Meyer curves were generated for two groups of patients, those above and below NLR cutoff thresholds. Two-sample T-test was performed to test for significant differences in LOS and duration on VV-ECMO.

RESULTS

Twenty-six patients were included in the study for final analyses. There was an overall mortality of 39% (n = 10). ROC curve analysis and Youden's J statistic revealed an optimal cut-off value of pre-ECMO NLR = 11.005 and on-ECMO NLR = 17.616. Results showed that the patient group placed on VV-ECMO with a pre-ECMO NLR less than 11.005 experienced no mortality (n = 7) and a median LOS of 28 days (IQR = 14.5-64.5 days). The patient group on VV-ECMO with a pre-ECMO NLR greater than 11.005 (n = 19) included all mortality (n = 10) and had a median LOS of 49 days (IQR = 25.5-63.5 days). The patient group with on-ECMO NLR less than 17.616 also conferred a survival advantage. There was no significant difference in LOS or duration on VV-ECMO between the two groups, pre-ECMO or on-ECMO.

CONCLUSIONS

 A pre-ECMO NLR cutoff was identified and offered statistically significant prognostic value in predicting mortality. A lower on-ECMO NLR value also indicated a survival advantage. Future studies should include NLR within multivariate models to better discern the effect of NLR and elucidate how it can be factored into clinical decision-making. Importantly, this data can be expanded to assess the predictive value of NLR pertaining to the COVID-19-induced ARDS population and matched cohorts.

Timing of Lung Transplant Referral in Patients with Severe COVID-19 Lung Injury Supported by ECMO

Severe respiratory failure caused by COVID-19 often requires mechanical ventilation, including extracorporeal membrane oxygenation (ECMO). In rare cases, lung transplantation (LTx) may be considered as a last resort. However, uncertainties remain about patient selection and optimal timing for referral and listing. This retrospective study analyzed patients with severe COVID-19 who were supported by veno-venous ECMO and listed for LTx between July 2020 and June 2022. Out of the 20 patients in the study population, four who underwent LTx were excluded. The clinical characteristics of the remaining 16 patients were compared, including nine who recovered and seven who died while awaiting LTx. The median duration from hospitalization to listing was 85.5 days, and the median duration on the waitlist was 25.5 days. Younger age was significantly associated with a higher likelihood of recovery without LTx after a median of 59 days on ECMO, compared to those who died at a median of 99 days. In patients with severe COVID-19-induced lung damage supported by ECMO, referral to LTx should be delayed for 8-10 weeks after ECMO initiation, particularly for younger patients who have a higher probability of spontaneous recovery and may not require LTx.

Expert consensus statement on venovenous extracorporeal membrane oxygenation ECMO for COVID-19 severe ARDS: an international Delphi study

BACKGROUND

The high-quality evidence on managing COVID-19 patients requiring extracorporeal membrane oxygenation (ECMO) support is insufficient. Furthermore, there is little consensus on allocating ECMO resources when scarce. The paucity of evidence and the need for guidance on controversial topics required an international expert consensus statement to understand the role of ECMO in COVID-19 better. Twenty-two international ECMO experts worldwide work together to interpret the most recent findings of the evolving published research, statement formulation, and voting to achieve consensus.

OBJECTIVES

To guide the next generation of ECMO practitioners during future pandemics on tackling controversial topics pertaining to using ECMO for patients with COVID-19-related severe ARDS.

METHODS

The scientific committee was assembled of five chairpersons with more than 5 years of ECMO experience and a critical care background. Their roles were modifying and restructuring the panel's questions and, assisting with statement formulation in addition to expert composition and literature review. Experts are identified based on their clinical experience with ECMO (minimum of 5 years) and previous academic activity on a global scale, with a focus on diversity in gender, geography, area of expertise, and level of seniority. We used the modified Delphi technique rounds and the nominal group technique (NGT) through three face-to-face meetings and the voting on the statement was conducted anonymously. The entire process was planned to be carried out in five phases: identifying the gap of knowledge, validation, statement formulation, voting, and drafting, respectively.

RESULTS

In phase I, the scientific committee obtained 52 questions on controversial topics in ECMO for COVID-19, further reviewed for duplication and redundancy in phase II, resulting in nine domains with 32 questions with a validation rate exceeding 75% (Fig. 1). In phase III, 25 questions were used to formulate 14 statements, and six questions achieved no consensus on the statements. In phase IV, two voting rounds resulted in 14 statements that reached a consensus are included in four domains which are: patient selection, ECMO clinical management, operational and logistics management, and ethics.

CONCLUSION

Three years after the onset of COVID-19, our understanding of the role of ECMO has evolved. However, it is incomplete. Tota14 statements achieved consensus; included in four domains discussing patient selection, clinical ECMO management, operational and logistic ECMO management and ethics to guide next-generation ECMO providers during future pandemic situations.

Therapy and Outcome of Prolonged Veno-Venous ECMO Therapy of Critically Ill ARDS Patients

Veno-venous Extracorporeal Membrane Oxygenation (VV-ECMO) therapy has become increasingly used and established in many hospitals as a routine treatment. With ECMO-therapy being a resource-demanding procedure, it is of interest whether a more prolonged VV-ECMO treatment would hold sufficient therapeutic success. Our retrospective study included all VV-ECMO runs from 1 January 2020 to 31 June 2022. We divided all runs into four groups (<14 days, 14-27, 28-49, 50+) of different durations and looked for differences overall in hospital survival. Additionally, corresponding treatments and therapeutic modalities, as well as laboratory results, were analyzed. We included 117 patients. Of those, 97 (82.9%) received a VV-ECMO treatment longer than two weeks. We did not find a significant association between ECMO duration (p = 0.15) and increased mortality though a significant correlation between the patients' age and their probability of survival (p = 0.02). Notably, we found significantly lower interleukin-6 levels with an increase in therapy duration (p < 0.01). Our findings show no association between the duration of ECMO therapy and mortality. Thus, the treatment duration alone may not be used for making assumptions about the prospect of survival. However, attention is also increasingly focused on long-term outcomes, such as post-intensive care syndrome with severe impairments.

Multi-horizon predictive models for guiding extracorporeal resource allocation in critically ill COVID-19 patients

OBJECTIVE

Extracorporeal membrane oxygenation (ECMO) resource allocation tools are currently lacking. We developed machine learning (ML) models for predicting COVID-19 patients at risk of receiving ECMO to guide patient triage and resource allocation.

MATERIAL AND METHODS

We included COVID-19 patients admitted to intensive care units for >24 h from March 2020 to October 2021, divided into training and testing development and testing-only holdout cohorts. We developed ECMO deployment timely prediction model ForecastECMO using Gradient Boosting Tree (GBT), with pre-ECMO prediction horizons from 0 to 48 h, compared to PaO2/FiO2 ratio, Sequential Organ Failure Assessment score, PREdiction of Survival on ECMO Therapy score, logistic regression, and 30 pre-selected clinical variables GBT Clinical GBT models, with area under the receiver operator curve (AUROC) and precision recall curve (AUPRC) metrics.

RESULTS

ECMO prevalence was 2.89% and 1.73% in development and holdout cohorts. ForecastECMO had the best performance in both cohorts. At the 18-h prediction horizon, a potentially clinically actionable pre-ECMO window, ForecastECMO, had the highest AUROC (0.94 and 0.95) and AUPRC (0.54 and 0.37) in development and holdout cohorts in identifying ECMO patients without data 18 h prior to ECMO.

DISCUSSION AND CONCLUSIONS

We developed a multi-horizon model, ForecastECMO, with high performance in identifying patients receiving ECMO at various prediction horizons. This model has potential to be used as early alert tool to guide ECMO resource allocation for COVID-19 patients. Future prospective multicenter validation would provide evidence for generalizability and real-world application of such models to improve patient outcomes.

Otolaryngologic Symptom Severity Post SARS-CoV-2 Infection

Objective(s)

To assess laryngologic symptomatology following SARS-CoV-2 infection and determine whether symptom severity correlates with disease severity.

Methods

Single-institution survey study in participants with documented SARS-CoV-2 infection between March 2020 and February 2021. Data acquired included demographic, infection severity characteristics, comorbidities, and current upper aerodigestive symptoms via validated patient reported outcome measures.  Primary outcomes of interest were scores of symptom severity questionnaires. COVID-19 severity was defined by hospitalization status. Descriptive subgroup analyses were performed to investigate differences in demographics, comorbidities, and symptom severity in hospitalized participants stratified by ICU status. Multivariate logistical regression was used to evaluate significant differences in symptom severity scores by hospitalization status.

Results

Surveys were distributed to 5300 individuals with upper respiratory infections. Ultimately, 470 participants with COVID-19 were included where 352 were hospitalized and 118 were not hospitalized. Those not hospitalized were younger (45.87 vs. 56.28 years), more likely female (74.17 vs. 58.92%), and less likely white (44.17 vs. 52.41%). Severity of dysphonia, dyspnea, cough, and dysphagia was significantly worse in hospitalized patients overall and remained worse at all time points. Cough severity paradoxically worsened in hospitalized respondents over time. Dyspnea scores remained abnormally elevated in respondents even 12 months after resolution of infection.

Conclusion

Results indicate that laryngologic symptoms are expected to be worse in patients hospitalized with COVID-19. Dyspnea and cough symptoms can be expected to persist or even worsen by one-year post infection in those who were hospitalized. Dysphagia and dysphonia symptoms were mild. Non-hospitalized participants tended to have minimal residual symptoms by one year after infection.

Same but Different-ECMO in COVID-19 and ARDS of Other Etiologies. Comparison of Survival Outcomes and Management in Different ARDS Groups

Background: COVID-19 has led to increased numbers of patients in need of venovenous extracorporeal membrane oxygenation (ECMO) support, but knowledge on management in comparison to acute respiratory distress syndrome (ARDS) of other etiologies is still lacking. We analyzed venovenous ECMO management and survival outcomes in patients with COVID-19 in comparison to influenza ARDS and pulmonary ARDS of other origin. Results: Retrospective analysis of prospective venovenous ECMO registry-based data collection was performed. One hundred consecutive venovenous ECMO patients with severe ARDS were included (41 COVID-19, 24 influenza A, 35 ARDS of other etiologies). Patients with COVID-19 had higher BMI (body mass index), lower SOFA (Sequential Organ Failure Assessment) and APACHE II (Acute Physiology and Chronic Health Evaluation II) scores, lower C-reactive protein and procalcitonin levels and less vasoactive support at ECMO initiation. Significantly more patients were mechanically ventilated for more than 7 days prior to ECMO initiation in the COVID-19 group, however they were ventilated with lower tidal volumes and more often received additional rescue therapies prior to and on ECMO. COVID-19 patients had significantly more barotrauma and thrombotic events on ECMO. There were no differences in weaning of ECMO, however duration of ECMO runs and ICU length of stay was significantly longer in the COVID-19 group. The leading cause of death in the COVID-19 group was irreversible respiratory failure, while uncontrolled sepsis and multiorgan failure were leading causes in the other 2 groups. All patients who survived ICU treatment were discharged out of hospital, and there were no differences in survival among groups at 180 days. Conclusions: Survival outcomes of venovenous ECMO patients do not differ between COVID-19 and ARDS of other pulmonary etiologies. ARDS guidelines were in greater proportion adhered to in COVID-19 patients, with, however, longer time to ECMO initiation. COVID-19 ARDS seems specific as a more single-organ disease with longer ECMO duration and irreversible respiratory failure as a main cause of ICU mortality.

Dynamic coagulofibrinolytic responses under long-term VV-ECMO management without anticoagulation in a COVID-19-ARDS patient: A case report

RATIONALE

Venovenous extracorporeal membrane oxygenation (ECMO) is recommended for the treatment of critically ill patients with acute respiratory distress syndrome due to coronavirus disease 2019 (COVID-19). However, ECMO management can cause both bleeding and thrombotic complications. There are insufficient coagulofibrinolytic data for appropriate ECMO management in patients with COVID-19.

PATIENT CONCERNS

A 48-year-old man with severe COVID-19-acute respiratory distress syndrome underwent long-term venovenous ECMO management for 48 days. Refractory oronasal bleeding developed on day 13, so the administration of unfractionated heparin was ceased for 29 days.

DIAGNOSIS

The patient showed dynamic coagulofibrinolytic responses associated with ECMO management, as shown by fibrin/fibrinogen degradation products, soluble fibrin, thrombin-antithrombin complex, and plasmin-α2-plasmin inhibitor complex elevations, suggesting the development of ECMO-induced coagulopathy.

INTERVENTIONS

We assessed coagulofibrinolytic markers to decide the appropriate timing for controlling excessive activation of coagulation by exchanging ECMO circuits. Moreover, viscoelastic hemostatic assays were used for adequate transfusion of blood products.

OUTCOMES

Safe long-term ECMO management was completed, which was withdrawn on day 48. The patient was weaned off mechanical ventilation on day 57 and was transferred to another hospital for rehabilitation.

LESSONS

Monitoring the coagulofibrinolytic status using markers and viscoelastic hemostatic assays may be effective for safe long-term ECMO management even without anticoagulant therapy.

The role of ECMO in COVID-19 acute respiratory failure: Defining risk factors for mortality

BACKGROUND

Veno-venous extracorporeal membrane oxygenation (VV ECMO) utilization increased substantially during the COVID-19 pandemic, but without patient selection criteria.

METHODS

We conducted a retrospective review of all adult patients with COVID-19-associated ARDS placed on VV ECMO at our institution from April 2020 through June 2022.

RESULTS

162 patients were included (n = 95 Pre-Delta; n = 58 Delta; n = 9 Omicron). The frequency of ECMO duration greater than three weeks was variable by pandemic period (17% pre-Delta, 41% Delta, 22% Omicron, p = 0.003). In-hospital mortality was 60.5%. Age ≥50 years (RR 1.28, 95% CI 1.01, 1.62), ≥7 days of respiratory support (1.39, 95% CI 1.05, 1.83) and pre-cannulation renal failure requiring dialysis (RR 1.42, 95% CI 1.13, 1.78) were associated with mortality.

CONCLUSIONS

In this cohort of VV ECMO patients with COVID-19, older age, a longer duration of pre-ECMO respiratory support, and pre-ECMO renal failure all increased the risk of mortality by approximately 30%.

COVID-19-Related ARDS: Key Mechanistic Features and Treatments

Acute respiratory distress syndrome (ARDS) is a heterogeneous syndrome historically characterized by the presence of severe hypoxemia, high-permeability pulmonary edema manifesting as diffuse alveolar infiltrate on chest radiograph, and reduced compliance of the integrated respiratory system as a result of widespread compressive atelectasis and fluid-filled alveoli. Coronavirus disease 19 (COVID-19)-associated ARDS (C-ARDS) is a novel etiology caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that may present with distinct clinical features as a result of the viral pathobiology unique to SARS-CoV-2. In particular, severe injury to the pulmonary vascular endothelium, accompanied by the presence of diffuse microthrombi in the pulmonary microcirculation, can lead to a clinical presentation in which the severity of impaired gas exchange becomes uncoupled from lung capacity and respiratory mechanics. The purpose of this review is to highlight the key mechanistic features of C-ARDS and to discuss the implications these features have on its treatment. In some patients with C-ARDS, rigid adherence to guidelines derived from clinical trials in the pre-COVID era may not be appropriate.

ECMO-Kanülierung bei COVID-19

Hintergrund

Die Coronavirus Disease 2019 (COVID-19) kann zu einem schwerem therapierefraktären Lungenversagen führen. Die temporäre venovenöse extrakorporale Membranoxygenierung (v.v.-ECMO) stellt hierbei eine etablierte supportive Therapie dar, ist jedoch weiterhin mit einer sehr hohen Mortalität verbunden.

Fragestellung

In dieser Arbeit soll erforscht werden, ob die Kanülierungsstrategie der v.v.-ECMO einen Einfluss auf das Therapieergebnis bei COVID-19 hat.

Material und Methoden

Alle Patienten, die zwischen März 2020 und November 2021 bei COVID-19 in einem universitären Zentrum mit einer v.v.-ECMO behandelt wurden (n = 75), wurden prospektiv in eine Datenbank eingeschlossen. Die Patienten wurden hinsichtlich der Kanülierung der ECMO (femorofemoral: n = 20, femorojugulär: n = 55) in 2 Gruppen unterteilt und das Therapieergebnis retrospektiv verglichen.

Ergebnisse

In beiden Gruppen traten bei mehr als 70 % der Patienten während der ECMO-Therapie Komplikationen auf, wobei am häufigsten eine Sepsis (> 50 % der Patienten) beobachtet wurde. Hinsichtlich des Therapieergebnisses (ECMO-Entwöhnung, Tod im Krankenhausaufenthalt und 6‑Monate-Überleben) ergaben sich keine Unterschiede in Bezug auf die Kanülierungsstrategie der ECMO. Insgesamt beobachteten wir eine Krankenhausmortalität von rund 70 %. Die Dauer der komplikationsfreien ECMO-Therapie erschien in der femorojugulären Gruppe jedoch verlängert.

Diskussion

Die ECMO-Therapie bei COVID-19 zeigt neben der Notwendigkeit einer langen Therapiedauer eine hohe Mortalität. Die Kanülierungsstrategie scheint keinen direkten Einfluss auf das Therapieergebnis zu haben, eine femorojuguläre Kanülierung könnte aber insbesondere die Mobilisierung der Patienten sowie die komplikationsfreie Therapiedauer positiv beeinflussen.

Right Ventricular Dysfunction is Associated with Increased Mortality in Patients Requiring Venovenous Extracorporeal Membrane Oxygenation for Coronavirus Disease 2019

Respiratory failure caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is associated with mortality. Patients unresponsive to conventional therapy may benefit from temporary venovenous extracorporeal membrane oxygenation (VV-ECMO). We investigated clinical and echocardiographic characteristics, particularly, right ventricular dysfunction, with survival in patients with respiratory failure caused by SARS-CoV-2. We performed a single-center retrospective cohort study of patients requiring VV-ECMO for respiratory failure from COVID-19 infection between January 2020 and December 2020. Demographics, comorbidities, laboratory parameters, and echocardiographic features of left and right ventricular (LV/RV) function were compared between patients who survived and those who could not be weaned from VV-ECMO. In addition, we evaluated outcomes in a separate population managed with venoarterial extracorporeal membrane oxygenation (VA-ECMO). In total, 10/17 patients failed to wean from VV-ECMO and died in the hospital on average 41.5 ± 10.9 days post admission. Seven were decannulated (41%) and survived to hospital discharge. There were no significant differences in demographics, comorbidities, and laboratory parameters between groups. Moderate to severe RV dysfunction was significantly more in those who died (8/10, 80%) compared to survivors (0/7, 0%) (p = 0.002). Patients supported with VA-ECMO had superior survival with 5/9 patients (56%) decannulated and discharged. Moderate to severe RV dysfunction is associated with increased mortality in patients with respiratory failure requiring VV-ECMO for COVID-19.

Lung transplantation for COVID-19 associated ARDS: Patience is a virtue

Not applicable.

Evolving outcomes of extracorporeal membrane oxygenation during the first 2 years of the COVID-19 pandemic: a systematic review and meta-analysis

Background

Extracorporeal membrane oxygenation (ECMO) has been used extensively for coronavirus disease 2019 (COVID-19)-related acute respiratory distress syndrome (ARDS). Reports early in the pandemic suggested that mortality in patients with COVID-19 receiving ECMO was comparable to non-COVID-19-related ARDS. However, subsequent reports suggested that mortality appeared to be increasing over time. Therefore, we conducted an updated systematic review and meta-analysis, to characterise changes in mortality over time and elucidate risk factors for poor outcomes.

Methods

We conducted a meta-analysis (CRD42021271202), searching MEDLINE, Embase, Cochrane, and Scopus databases, from 1 December 2019 to 26 January 2022, for studies reporting on mortality among adults with COVID-19 receiving ECMO. We also captured hospital and intensive care unit lengths of stay, duration of mechanical ventilation and ECMO, as well as complications of ECMO. We conducted random-effects meta-analyses, assessed risk of bias of included studies using the Joanna Briggs Institute checklist and evaluated certainty of pooled estimates using GRADE methodology.

Results

Of 4522 citations, we included 52 studies comprising 18,211 patients in the meta-analysis. The pooled mortality rate among patients with COVID-19 requiring ECMO was 48.8% (95% confidence interval 44.8–52.9%, high certainty). Mortality was higher among studies which enrolled patients later in the pandemic as opposed to earlier (1st half 2020: 41.2%, 2nd half 2020: 46.4%, 1st half 2021: 62.0%, 2nd half 2021: 46.5%, interaction p value = 0.0014). Predictors of increased mortality included age, the time of final patient enrolment from 1 January 2020, and the proportion of patients receiving corticosteroids, and reduced duration of ECMO run.

Conclusions

The mortality rate for patients receiving ECMO for COVID-19-related ARDS has increased as the pandemic has progressed. The reasons for this are likely multifactorial; however, as outcomes for these patients evolve, the decision to initiate ECMO should include the best contextual estimate of mortality at the time of ECMO initiation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04011-2.

Temporary mechanical circulatory support for COVID‐19 patients: A systematic review of literature

Objective

Myocardial damage occurs in up to 25% of coronavirus disease 2019 (COVID‐19) cases. While veno‐venous extracorporeal life support (V‐V ECLS) is used as respiratory support, mechanical circulatory support (MCS) may be required for severe cardiac dysfunction. This systematic review summarizes the available literature regarding MCS use rates, disease drivers for MCS initiation, and MCS outcomes in COVID‐19 patients.

Methods

PubMed/EMBASE were searched until October 14, 2021. Articles including adults receiving ECLS for COVID‐19 were included. The primary outcome was the rate of MCS use. Secondary outcomes included mortality at follow‐up, ECLS conversion rate, intubation‐to‐cannulation time, time on ECLS, cardiac diseases, use of inotropes, and vasopressors.

Results

Twenty‐eight observational studies (comprising both ECLS‐only populations and ECLS patients as part of larger populations) included 4218 COVID‐19 patients (females: 28.8%; median age: 54.3 years, 95%CI: 50.7–57.8) of whom 2774 (65.8%) required ECLS with the majority (92.7%) on V‐V ECLS, 4.7% on veno‐arterial ECLS and/or Impella, and 2.6% on other ECLS. Acute heart failure, cardiogenic shock, and cardiac arrest were reported in 7.8%, 9.7%, and 6.6% of patients, respectively. Vasopressors were used in 37.2%. Overall, 3.1% of patients required an ECLS change from V‐V ECLS to MCS for heart failure, myocarditis, or myocardial infarction. The median ECLS duration was 15.9 days (95%CI: 13.9–16.3), with an overall survival of 54.6% and 28.1% in V‐V ECLS and MCS patients. One study reported 61.1% survival with oxy‐right ventricular assist device.

Conclusion

MCS use for cardiocirculatory compromise has been reported in 7.3% of COVID‐19 patients requiring ECLS, which is a lower percentage compared to the incidence of any severe cardiocirculatory complication. Based on the poor survival rates, further investigations are warranted to establish the most appropriated indications and timing for MCS in COVID‐19.

The Year in Extracorporeal Membrane Oxygenation: Selected Highlights From 2021

This review summarizes the extracorporeal membrane oxygenation (ECMO) or extracorporeal life support literature published in 2021. This Selected Highlights article is not intended to be an exhaustive review of the literature, but rather a summarizing of key themes that developed in the ECMO literature during 2021. The primary topics presented include the following: ECMO for coronavirus disease 2019, extracorporeal cardiopulmonary resuscitation, periprocedural cardiopulmonary support with ECMO, and anticoagulation for ECMO.

ECMO Long Haulers: A Distinct Phenotype of COVID-19-Associated ARDS With Implications for Lung Transplant Candidacy

BACKGROUND

Studies indicate that the recovery from coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome may be slower than other viral pneumonia. There are limited data to guide decisions among patients who need extracorporeal membrane oxygenation (ECMO) support, especially the expected time of recovery and considering lung transplantation (LT).

METHODS

This was a retrospective chart review of patients with COVID-19-associated acute respiratory distress syndrome placed on ECMO between March 1, 2020, and September 15, 2021 (n = 20; median age, 44 y; range, 22-62 y; male:female, 15:5). We contrasted the baseline variables and clinical course of patients with and without the need for ECMO support >30 d (ECMO long haulers, n = 10).

RESULTS

Ten patients met the criteria for ECMO long haulers (median duration of ECMO, 86 d; range, 42-201 d). The long haulers were healthier at baseline with fewer comorbidities but had worse pulmonary compliance and higher partial pressure of CO2. They had a significantly higher number of membrane oxygenator failures, changes to their cannulation sites, and suffer more complications on ECMO. One of the long hauler was bridged to LT while another 6 patients recovered and were discharged. Overall survival was better among the ECMO long haulers (70% versus 20%; 9.3, 1.2-73; P = 0.03).

CONCLUSIONS

Despite worse pulmonary physiology, frequent complications, and a tortuous hospital course that may appear to portend a poor prognosis, ECMO long haulers have the potential to recover and be weaned off ECMO without the need for LT. A customized approach comprising a more conservative timeline for the consideration of LT may be prudent among these patients.

Early Initiation of Venovenous Extracorporeal Membrane Oxygenation for Critically Ill COVID-19 Patients

The optimal timing for initiating extracorporeal membrane oxygenation (ECMO) after starting mechanical ventilation has yet to be clarified. We report herein the cases of two patients with coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS) who were successfully managed with an early ECMO induction strategy. Case 1 involved a 64-year-old man admitted in respiratory distress with polymerase chain reaction-confirmed COVID-19. On day 5 at hospital, he was intubated, but oxygenation remained unimproved despite mechanical ventilation treatment with high positive end-expiratory pressure (PEEP) (PaO₂/FiO₂ [P/F] ratio, 127; Respiratory ECMO Survival Prediction [RESP] score, 4). ECMO was initiated 4 hours after intubation, and stopped on day 16 at hospital. The patient was discharged from hospital on day 36. Case 2 involved a 49-year-old man who had been admitted 8 days prior. He was intubated on hospital on day 2. High PEEP mechanical ventilation did not improve oxygenation (P/F ratio, 93; RESP score, 7). ECMO was stopped on hospital on day 7 and he was discharged from hospital on day 21. The strategy of early initiation of ECMO in these two cases may have minimized the risk of ventilation-related lung injury and contributed to the achievement of favorable outcomes.

Coagulation abnormalities in patients with COVID-19 on venovenous ECLS increased risk for technical complications and support times but had no impact on survival

BACKGROUND

Patients with severe coronavirus disease-19 (COVID-19)-associated acute respiratory distress on venovenous extracorporeal lung support (V-V ECLS) showed high incidence of vascular as well as ECLS-related thrombotic complications. The latter may influence the outcome of the patients.

METHODS

This is a retrospective monocentric study on prospectively collected data of technical complications including 69 adult COVID-19 patients on V-V ECLS (ECLS Registry, March 2020 until April 2021) without and with system exchanges. Alterations in ECLS-specific data, hemolysis, coagulation and hemostasis parameters were analyzed.

RESULTS

Every second COVID-19 patient on V-V ECLS developed technical complications. Optimized ECLS management at our ECLS center reduced cases of acute clot formation (pump head thrombosis, acute oxygenator thrombosis) (17%), and allowed early identification of progressive clotting processes (worsened gas transfer, coagulation disorder) (14%, 54%) with a significant overhang of hyperfibrinolysis (37%). Although COVID-19 disease and technical complications caused prolonged length of stay at the intensive care unit and ECLS support times, the proportion of successful weaning and survival rates were comparable with patients without system exchange.

CONCLUSION

The survival of ECLS patients with COVID-19 was independent of the requirement for system exchange due to technical-induced coagulation disorders. Close monitoring for circuit clotting is mandatory in COVID-19 patients and is one prerequisite for successful organ support in these difficult patients.

Rehabilitation Characteristics of Acute-stage COVID-19 Survivors Managed with Extracorporeal Membrane Oxygenation in the Intensive Care Unit

Objectives:

This study aimed to describe the rehabilitation characteristics of patients with acute stage coronavirus disease managed with extracorporeal membrane oxygenation (ECMO) in the intensive care unit.

Methods:

This retrospective study enrolled coronavirus disease patients who underwent rehabilitation following ECMO between April 21, 2020, and August 20, 2021. The following patient data were evaluated: age, sex, weaning, peak C-reactive protein, lowest albumin level, white blood cell count, use of steroids and muscle relaxants, duration of respiratory management, ECMO management and rehabilitation, Medical Research Council (MRC) score, and Barthel index after sedation and at discharge.

Results:

ECMO was performed in 20 patients, and 16 were weaned successfully. The median durations of ECMO and respiratory management in survivors were 14.5 and 38 days, respectively. The median MRC scores after sedation and after rehabilitation therapy were 18 and 45, respectively. The median rehabilitation duration after sedation was 14 days. The MRC score after sedation showed significant correlations with the durations of ECMO and intubation. The median Barthel index values after sedation and at discharge were 0 and 30, respectively.

Conclusions:

Rehabilitation was important for patients with severe coronavirus disease because muscle weakness advanced in proportion with the durations of ECMO and ventilation management in the intensive care unit.

Multiple Secondary Healthcare-Associated Infections Due to Carbapenem-Resistant Organisms in a Critically Ill COVID-19 Patient on Extensively Prolonged Venovenous Extracorporeal Membrane Oxygenation Support-A Case Report

Patients with severe Coronavirus disease 2019 (COVID-19) are at high risk for secondary infection with multidrug-resistant organisms (MDROs). Secondary infections contribute to a more severe clinical course and longer intensive care unit (ICU) stays in patients with COVID-19. A man in his 60s was admitted to the ICU at a university hospital for severe COVID-19 pneumonia requiring mechanical ventilation. His respiratory condition worsened further due to persistent bacteremia caused by imipenem-non-susceptible Klebsiella aerogenes and he required VV-ECMO. Subsequently, he developed a catheter-related bloodstream infection (CRBSI) due to Candida albicans, ventilator-associated pneumonia (VAP) due to multidrug-resistant Pseudomonas aeruginosa (MDRP), and a perianal abscess due to carbapenem-resistant K. aerogenes despite infection control procedures that maximized contact precautions and the absence of MDRO contamination in the patient’s room environment. He was decannulated from VV-ECMO after a total of 72 days of ECMO support, and was eventually weaned off ventilator support and discharged from the ICU on day 138. This case highlights the challenges of preventing, diagnosing, and treating multidrug-resistant organisms and healthcare-associated infections (HAIs) in the critical care management of severe COVID-19. In addition to the stringent implementation of infection prevention measures, a high index of suspicion and a careful evaluation of HAIs are required in such patients.

Extracorporeal membrane oxygenation support for SARS-CoV-2: a multi-centered, prospective, observational study in critically ill 92 patients in Saudi Arabia

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been used as a rescue strategy in patients with severe with acute respiratory distress syndrome (ARDS) due to SARS-CoV-2 infection, but there has been little evidence of its efficacy.

OBJECTIVES

To describe the effect of ECMO rescue therapy on patient-important outcomes in patients with severe SARS-CoV-2.

METHODS

A case series study was conducted for the laboratory-confirmed SARS-CoV-2 patients who were admitted to the ICUs of 22 Saudi hospitals, between March 1, 2020, and October 30, 2020, by reviewing patient's medical records prospectively.

RESULTS

ECMO use was associated with higher in-hospital mortality (40.2% vs. 48.9%; p = 0.000); lower COVID-19 virological cure (41.3% vs 14.1%, p = 0.000); and longer hospitalization (20.2 days vs 29.1 days; p = 0.000), ICU stay (12.6 vs 26 days; p = 0.000) and mechanical ventilation use (14.2 days vs 22.4 days; p = 0.000) compared to non-ECMO group. Also, there was a high number of patients with septic shock (19.6%) and multiple organ failure (10.9%); and more complications occurred at any time during hospitalization [pneumothorax (5% vs 29.3%, p = 0.000), bleeding requiring blood transfusion (7.1% vs 38%, p = 0.000), pulmonary embolism (6.4% vs 15.2%, p = 0.016), and gastrointestinal bleeding (3.3% vs 8.7%, p = 0.017)] in the ECMO group. However, PaO2 was significantly higher in the 72-h post-ECMO initiation group and PCO2 was significantly lower in the 72-h post-ECMO start group than those in the 12-h pre-ECMO group (62.9 vs. 70 mmHg, p = 0.002 and 61.8 vs. 51 mmHg, p = 0.042, respectively).

CONCLUSION

Following the use of ECMO, the mortality rate of patients and length of ICU and hospital stay were not improved. However, these findings need to be carefully interpreted, as most of our cohort patients were relatively old and had multiple severe comorbidities. Future randomized trials, although challenging to conduct, are highly needed to confirm or dispute reported observations.

Clinical Characteristics Between Survivors and Nonsurvivors of COVID-19 Patients Requiring Extracorporeal Membrane Oxygenation (ECMO) Support: A Systematic Review and Meta-Analysis

Background: The use of extracorporeal membrane oxygenation (ECMO) in coronavirus disease 2019 (COVID-19) for refractory respiratory failure, severe cardiac dysfunction, and bridge to lung transplantation has been steadily increasing during the ongoing global pandemic. Objective: Our meta-analysis aims to compare the clinical characteristics between COVID-19 survivors and nonsurvivors requiring ECMO support. Methods: A systematic search of Pubmed, Cochrane, Embase, Scopus, and Web of Science databases was performed between December first, 2019, to June first, 2021. Studies with comparative data of COVID-19 ECMO patients were selected, in which clinical characteristics and complications were assessed. Results: Sixteen cohort studies involving 706 COVID-19 patients requiring ECMO support with pooled mortality rate of 40% were included. Younger age (mean 51 years vs 55 years; P < .001), fewer comorbidities (23% vs 31%; odds ratio [OR] 0.55; P  =  .02), and less renal replacement therapy (RRT) (21% vs 39%; OR 0.41; P  =  .007) and vasopressor (76% vs 92%; OR 0.35; P  =  .008) requirement were demonstrated in COVID-19 survivors requiring ECMO support than nonsurvivors. Survivors also had higher pre-ECMO pH (mean 7.33 vs 7.26; P < .001) than nonsurvivors. No difference was observed in gender, body mass index, duration of mechanical ventilation (MV) before ECMO support initiation, total ECMO support duration, and pre-ECMO parameters of PaO2/FiO2 ratio, tidal volume (mL/kg), positive end-expiratory pressure, and plateau pressure. The rate of bleeding complications was lower in survivors (32% vs 59%; OR 0.36; P  =  .001) than nonsurvivors, but no difference was observed in thromboembolism and secondary infections. Conclusions: We found advanced age, multiple comorbidities, lower pre-ECMO pH, greater RRT, and vasopressor requirements, and bleeding are predictors of death in COVID-19 patients requiring ECMO support. The duration of MV before ECMO support initiation and total ECMO support duration was similar among survivors and nonsurvivors. Our study results have important clinical implications when considering ECMO support in critically ill COVID-19 patients.

Risk Factors of Mortality for Patients Receiving Venovenous Extracorporeal Membrane Oxygenation for COVID-19 Acute Respiratory Distress Syndrome

Background: Venovenous extracorporeal membrane oxygenation (VV-ECMO) for select adults with severe acute respiratory distress syndrome (ARDS) cause by coronavirus disease 2019 (COVID-19) infection is a guideline-supported therapy with associated hospital survival of 62%-74%, similar to expected survival with VV-ECMO for other indications. However, ECMO is a resource-heavy intervention, and these patients often require long ECMO runs and prolonged intensive care unit (ICU) care. Identifying factors associated with mortality in VV-ECMO patients with COVID-19 infection can inform the evaluation of ECMO candidates as well as prognostication for those patients on prolonged VV-ECMO. Patients and Methods: This was a retrospective cohort study that included all patients who received either VV- or venoarteriovenous (VAV)-ECMO at one of four ECMO Centers of Excellence in the state of Minnesota between March 1, 2020 and November 1, 2020. The primary outcome was 60-day survival. Secondary outcomes were hospital complications, infectious complications, and complications from ECMO. Results: There were 46 patients who met criteria during this study period and 30 survived to 60-day follow-up (65.2%). Prior to cannulation, older patient age (55.5 in non-survivors vs. 49.1 years in survivors; p = 0.03), lower P/F ratio (62.1 vs. 76.2; p = 0.04), and higher sequential organ failure assessment (SOFA) score (8.1 vs. 6.6; p = 0.02) were identified as risk factors for mortality. After ECMO cannulation, increased mortality was associated with increased number of antibiotic days (25.9 vs. 14.5; p = 0.04), increased number of transfusions (23.9 vs. 9.9; p = 0.03), elevated white blood cell (WBC) count at post-ECMO days one through three, elevated D-dimer at post-ECMO day 21-27, and decreased platelet count from post-ECMO days 14 and onward using univariable analysis. Conclusions: Multiple markers of infection including leukocytosis, thrombocytopenia, and increased antibiotic days are associated with increased mortality in patients placed on VV-ECMO for COVID-19 infection and subsequent ARDS. Knowledge of these factors may assist with determining appropriate candidates for this limited resource as well as direct goals of care in prolonged ECMO courses.

Contraindications to the Initiation of Veno-Venous ECMO for Severe Acute Respiratory Failure in Adults: A Systematic Review and Practical Approach Based on the Current Literature

(1) Background: Extracorporeal membrane oxygenation (ECMO) is increasingly used for acute respiratory failure with few absolute but many relative contraindications. The provider in charge often has a difficult time weighing indications and contraindications to anticipate if the patient will benefit from this treatment, a decision that often decides life and death for the patient. To assist in this process in coming to a good evidence-based decision, we reviewed the available literature. (2) Methods: We performed a systematic review through a literature search of the MEDLINE database of former and current absolute and relative contraindications to the initiation of ECMO treatment. (3) Results: The following relative and absolute contraindications were identified in the literature: absolute-refusal of the use of extracorporeal techniques by the patient, advanced stage of cancer, fatal intracerebral hemorrhage/cerebral herniation/intractable intracranial hypertension, irreversible destruction of the lung parenchyma without the possibility of transplantation, and contraindications to lung transplantation; relative-advanced age, immunosuppressed patients/pharmacological immunosuppression, injurious ventilator settings > 7 days, right-heart failure, hematologic malignancies, especially bone marrow transplantation and graft-versus-host disease, SAPS II score ≥ 60 points, SOFA score > 12 points, PRESERVE score ≥ 5 points, RESP score ≤ -2 points, PRESET score ≥ 6 points, and "do not attempt resuscitation" order (DN(A)R status). (4) Conclusions: We provide a simple-to-follow algorithm that incorporates absolute and relative contraindications to the initiation of ECMO treatment. This algorithm attempts to weigh pros and cons regarding the benefit for an individual patient and hopefully assists caregivers to make better, informed decisions.

Transition from Simple V-V to V-A and Hybrid ECMO Configurations in COVID-19 ARDS

In SARS-CoV-2 patients with severe acute respiratory distress syndrome (ARDS), Veno-Venous Extracorporeal Membrane Oxygenation (V-V ECMO) was shown to provide valuable treatment with reasonable survival in large multi-centre investigations. However, in some patients, conversion to modified ECMO support forms may be needed. In this single-centre retrospective registry, all consecutive patients receiving V-V ECMO between 1 March 2020 to 1 May 2021 were included and analysed. The patient cohort was divided into two groups: those who remained on V-V ECMO and those who required conversion to other modalities. Seventy-eight patients were included, with fourteen cases (18%) requiring conversions to veno-arterial (V-A) or hybrid ECMO. The reasons for the ECMO mode configuration change were inadequate drainage (35.7%), inadequate perfusion (14.3%), myocardial infarction (7.1%), hypovolemic shock (14.3%), cardiogenic shock (14.3%) and septic shock (7.1%). In multivariable analysis, the use of dobutamine (p = 0.007) and a shorter ICU duration (p = 0.047) predicted the conversion. The 30-day mortality was higher in converted patients (log-rank p = 0.029). Overall, only 19 patients (24.4%) survived to discharge or lung transplantation. Adverse events were more common after conversion and included renal, cardiovascular and ECMO-circuit complications. Conversion itself was not associated with mortality in the multivariable analysis. In conclusion, as many as 18% of patients undergoing V-V ECMO for COVID-19 ARDS may require conversion to advanced ECMO support.

Extracorporeal Membrane Oxygenation for COVID-19: Updated 2021 Guidelines from the Extracorporeal Life Support Organization

DISCLAIMER

This is an updated guideline from the Extracorporeal Life Support Organization (ELSO) for the role of extracorporeal membrane oxygenation (ECMO) for patients with severe cardiopulmonary failure due to coronavirus disease 2019 (COVID-19). The great majority of COVID-19 patients (>90%) requiring ECMO have been supported using venovenous (V-V) ECMO for acute respiratory distress syndrome (ARDS). While COVID-19 ECMO run duration may be longer than in non-COVID-19 ECMO patients, published mortality appears to be similar between the two groups. However, data collection is ongoing, and there is a signal that overall mortality may be increasing. Conventional selection criteria for COVID-19-related ECMO should be used; however, when resources become more constrained during a pandemic, more stringent contraindications should be implemented. Formation of regional ECMO referral networks may facilitate communication, resource sharing, expedited patient referral, and mobile ECMO retrieval. There are no data to suggest deviation from conventional ECMO device or patient management when applying ECMO for COVID-19 patients. Rarely, children may require ECMO support for COVID-19-related ARDS, myocarditis, or multisystem inflammatory syndrome in children (MIS-C); conventional selection criteria and management practices should be the standard. We strongly encourage participation in data submission to investigate the optimal use of ECMO for COVID-19.