Perception of prolonged extracorporeal membrane oxygenation in Europe: an EuroELSO survey

Prolonged extracorporeal membrane oxygenation in pediatrics: How long did we wait?

BACKGROUND

In this study, we aimed to evaluate the duration of extracorporeal membrane oxygenation (ECMO) and its effect on outcomes. Also, we sought to identify hospital mortality predictors and determine when ECMO support began to be ineffective.

METHODS

This was a single-center, retrospective cohort study conducted between January 2014 and January 2022. The prolonged ECMO (pECMO) cut-off point was accepted as 14 days.

RESULTS

Thirty-one (29.2%) of 106 patients followed up with ECMO had pECMO. The mean follow-up period of the patients who underwent pECMO was 22 (range, 15-72) days, and the mean age was 75 ± 72 months. According to the results of our heterogeneous study population, life expectancy decreased dramatically towards the 21st day. Hospital mortality predictors were determined in the logistic regression analysis in all ECMO groups in our study as high Pediatric Logistic Organ Dysfunction (PELOD) two score, continuous renal replacement therapy (CRRT) use, and sepsis. The pECMO mortality was 61.2% and the overall mortality was 53.0%, with the highest mortality rate in the bridge-to-transplant group (90.9%) because of lack of organ donation in our country.

CONCLUSIONS

In our study, the PELOD two score, presence of sepsis, and use of CRRT were found to be in the predictors of in-hospital ECMO mortality model. Considering the complications, in the COX regression model analysis, the factors affecting the probability of dying in patients followed under ECMO were found to be bleeding, thrombosis, and thrombocytopenia.

Survival and Long-Term Functional Status of COVID-19 Patients Requiring Prolonged Extracorporeal Membrane Oxygenation Support

Rationale: Severe cases of acute respiratory distress syndrome (ARDS) may require prolonged (>28 d) extracorporeal membrane oxygenation (ECMO). In nonresolving disease, recovery is uncertain, and lung transplant may be proposed. Objectives: This study aims to identify the variables influencing survival and to describe the functional status of these patients at 6 months. Methods: This was a retrospective, multicenter, observational cohort study including patients requiring ECMO support for coronavirus disease (COVID-19)-related ARDS for >28 days. Multivariate analysis was performed using Cox regression in preselected variables and in least absolute shrinkage and selection operator selected variables. In a post hoc analysis to account for confounders and differences in awake strategy use by centers, treatment effects of the awake strategy were estimated using an augmented inverse probability weighting estimator with robust standard errors clustered by center. Results: Between March 15, 2020 and March 15, 2021, 120 patients required ECMO for >28 days. Sixty-four patients (53.3%) survived decannulation, 62 (51.7%) were alive at hospital discharge, and 61 (50.8%) were alive at 6-month follow-up. In the multivariate analysis, age (1.09; 95% confidence interval [CI], 1.03-1.15; P = 0.002) and an awake ECMO strategy (defined as the patient being awake, cooperative, and performing rehabilitation and physiotherapy with or without invasive mechanical ventilation at any time during the extracorporeal support) (0.14; 95% CI, 0.03-0.47; P = 0.003) were found to be predictors of hospital survival. At 6 months, 51 (42.5%) patients were at home, 42 (84.3%) of them without oxygen therapy. A cutoff point of 47 ECMO days had a 100% (95% CI, 76.8-100%) sensitivity and 60% (95% CI, 44.3-73.6%) specificity for oxygen therapy at 6 months, with 100% specificity being found in 97 days. Conclusions: Patients with COVID-19 who require ECMO for >28 days can survive with nonlimiting lung impairment. Age and an awake ECMO strategy may be associated with survival. Longer duration of support correlates with need for oxygen therapy at 6 months.

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.

Liberation From Venovenous Extracorporeal Membrane Oxygenation for Respiratory Failure: A Scoping Review

BACKGROUND

Safe and timely liberation from venovenous extracorporeal membrane oxygenation (ECMO) would be expected to reduce the duration of ECMO, the risk of complications, and costs. However, how to liberate patients from venovenous ECMO effectively remains understudied.

RESEARCH QUESTION

What is the current state of the evidence on liberation from venovenous ECMO?

STUDY DESIGN AND METHODS

We systematically searched for relevant publications on liberation from venovenous ECMO in Medline and EMBASE. Citations were included if the manuscripts provided any of the following: criteria for readiness for liberation, a liberation protocol, or a definition of successful decannulation or decannulation failure. We included randomized trials, observational trials, narrative reviews, guidelines, editorials, and commentaries. We excluded single case reports and citations where the full text was unavailable.

RESULTS

We screened 1,467 citations to identify 39 key publications on liberation from venovenous ECMO. We then summarized the data into five main topics: current strategies used for liberation, criteria used to define readiness for liberation, conducting liberation trials, criteria used to proceed with decannulation, and parameters used to predict decannulation outcomes.

INTERPRETATION

Practices on liberation from venovenous ECMO are heterogeneous and are influenced strongly by clinician preference. Additional research on liberation thresholds is needed to define optimal liberation strategies and to close existing knowledge gaps in essential topics on liberation from venovenous ECMO.

Outcomes of Extremely Prolonged (> 50 d) Venovenous Extracorporeal Membrane Oxygenation Support

OBJECTIVES

There has been a sustained increase in the utilization of venovenous extracorporeal membrane oxygenation (ECMO) over the last decade, further exacerbated by the COVID-19 pandemic. We set out to describe our institutional experience with extremely prolonged (> 50 d) venovenous ECMO support for recovery or bridge to lung transplant candidacy in patients with acute respiratory failure.

DESIGN

Retrospective cohort study.

SETTING

A large tertiary urban care center.

PATIENTS

Patients 18 years or older receiving venovenous ECMO support for greater than 50 days, with initial cannulation between January 2018 and January 2022.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred thirty patients were placed on venovenous ECMO during the study period. Of these, 12 received prolonged (> 50 d) venovenous ECMO support. Eleven patients (92%) suffered from adult respiratory distress syndrome (ARDS) secondary to COVID-19, while one patient with prior bilateral lung transplant suffered from ARDS secondary to bacterial pneumonia. The median age of patients was 39 years (interquartile range [IQR], 35-51 yr). The median duration of venovenous ECMO support was 94 days (IQR, 70-128 d), with a maximum of 180 days. Median time from intubation to cannulation was 5 days (IQR, 2-14 d). Nine patients (75%) were successfully mobilized while on venovenous ECMO support. Successful weaning of venovenous ECMO support occurred in eight patients (67%); 6 (50%) were bridged to lung transplantation and 2 (17%) were bridged to recovery. Of those successfully weaned, seven patients (88%) were discharged from the hospital. All seven patients discharged from the hospital were alive 6 months post-decannulation; 83% (5/6) with sufficient follow-up time were alive 1-year after decannulation.

CONCLUSIONS

Our experience suggests that extremely prolonged venovenous ECMO support to allow native lung recovery or optimization for lung transplantation may be a feasible strategy in select critically ill patients, further supporting the expanded utilization of venovenous ECMO for refractory respiratory failure.

Lung recovery with prolonged ECMO following fibrotic COVID-19 acute respiratory distress syndrome

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has been associated with acute respiratory distress syndrome (ARDS) and in some cases with pulmonary fibrosis. There is limited information regarding the long-term outcomes of patients who develop severe COVID-19 infection and subsequent pulmonary fibrosis. We present a patient with severe ARDS due to COVID-19 who required prolonged extra-corporeal oxygenation support and eventually recovered significant lung function. This case is unique because the patient survived one of the longest reported runs on extra-corporeal membrane oxygenation without requiring lung transplantation. Further, our patient developed severe parenchymal and airway distortion but ultimately resolved pulmonary fibrosis many months into the hospitalization. In addition to our detailed case discussion, we will provide a focused review on pulmonary fibrosis post COVID-19.

Be Patient: Prolonged Extracorporeal Membrane Oxygenation Support Including Full System Switch With Favorable Outcome

Despite tremendous advances in treatment, acute respiratory distress syndrome (ARDS) remains a disease with high mortality (42-48%). Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is often used as a last treatment option, which poses complex problems for the treatment team, especially with prolonged ECMO support. We report an interesting case of a 40-year-old female patient who developed influenza pneumonia leading to ARDS and subsequently requiring ECMO. Due to severe clotting complications, a prolonged ECMO run time with numerous filter changes was required. After a total of 56 days of ECMO therapy, the patient was successfully weaned. Fortunately, further in the course of treatment, complete recovery with restitutio ad integrum was achieved. A distinguishing feature of this case report is the description of a complete ECMO system change and the concurrent use of two ECMO systems for the same patient. Additionally, we provide data on the patient's current health-related quality of life as measured using the World Health Organization Disability Assessment Schedule 2.0.

Rehabilitation of adult patients on extracorporeal membrane oxygenation: A scoping review

OBJECTIVES

The objective of this study was to conduct a scoping review to comprehensively map the breadth of literature related to the rehabilitation of adult patients whilst on extracorporeal membrane oxygenation (ECMO) and identify gaps and areas for future research.

REVIEW METHOD USED

This review was conducted using recommended frameworks for methods and reporting including the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews.

DATE SOURCES

We searched seven databases from inception to June 2021 and included all study designs and grey literature.

REVIEW METHODS

Eligibility screening was completed by two independent reviewers according to inclusion and exclusion criteria, with any disagreement resolved by consensus or with consultation with a third reviewer. Two independent reviewers extracted data related to intervention characteristics, patient outcomes, feasibility, safety, hospital outcomes, and mortality using a custom-designed piloted form.

RESULTS

Of 8507 records, 185 original studies met inclusion criteria, with the majority being small retrospective studies. Rehabilitation was more commonly reported in patients on veno-venous rather than veno-arterial ECMO. Ambulation was the most commonly reported intervention (51% of studies). Critical gaps were identified including incomplete reporting of the intervention along with heterogeneity in the type and timing of outcome measures. Less than 50% of patients met eligibility criteria to participate, but screening for eligibility was infrequently reported (9% of studies). Delivery of rehabilitation during ECMO may be facilitated by an expert multidisciplinary team, along with a strategy that targets low sedation levels and an upper body cannulation approach.

CONCLUSIONS

Rehabilitation during ECMO is an emerging area of research and mostly consisted of small retrospective single-centre studies. Future research requires more robust methodological designs that include comprehensive screening of potential candidates with reporting of eligibility, more detailed descriptions of the rehabilitation interventions, inclusion of a core outcome set with defined measurement instruments, and consistent timing of outcome measurement.

Hospital survival outcomes in acute respiratory distress syndrome patients receiving veno-venous extracorporeal membrane oxygenation for longer than 28 days: A retrospective study

The successful use of prolonged (ie, >28 days) veno-venous extracorporeal membrane oxygenation (V-V ECMO) is being increasingly reported. However, limited data are available on its outcomes. This study investigated the outcomes of acute respiratory distress syndrome (ARDS) patients on prolonged ECMO support. We retrospectively evaluated 57 patients requiring V-V ECMO for ARDS between 2015 and 2020. The patients were divided into two groups according to ECMO duration: (a) ≤28 days group (n = 43, 75%) or (b) >28 days (n = 14, 25%) group. Clinical characteristics, complications, and outcomes between these two groups were statistically compared. There were no significant differences in demographics, comorbidity, ARDS etiology, and severity scores between the two groups. However, the mechanical ventilation period before ECMO initiation was significantly longer in the >28 days group than in the ≤28 days group (10.5 days vs. 1 day; P < .05). The incidence of positive bacterial blood culture results during ECMO was significantly higher in the >28 days group than in the ≤28 days group (43% vs. 9%; P < .05). Additionally, the hospital survival rate was significantly lower in the >28 days group than in the ≤28 days ECMO group (21% vs. 60%; P < .05). Prolonged ECMO was associated with worse hospital survival outcomes. Early initiation of ECMO along with meticulous care and appropriate treatment against infection during ECMO could improve the hospital survival of ARDS patients on prolonged ECMO support.

Month-long Respiratory Support by a Wearable Pumping Artificial Lung in an Ovine Model

BACKGROUND

A wearable artificial lung could improve lung transplantation outcomes by easing implementation of physical rehabilitation during long-term pretransplant respiratory support. The Modular Extracorporeal Lung Assist System (ModELAS) is a compact pumping artificial lung currently under development. This study evaluated the long-term in vivo performance of the ModELAS during venovenous support in awake sheep. Feedback from early trials and computational fluid dynamic analysis guided device design optimization along the way.

METHODS

The ModELAS was connected to healthy sheep via a dual-lumen cannula in the jugular vein. Sheep were housed in a fixed-tether pen while wearing the device in a holster during support. Targeted blood flow rate and support duration were 2-2.5 L/min and 28-30 days, respectively. Anticoagulation was maintained via systemic heparin. Device pumping and gas exchange performance and hematologic indicators of sheep physiology were measured throughout support.

RESULTS

Computational fluid dynamic-guided design modifications successfully decreased pump thrombogenicity from initial designs. For the optimized design, 4 of 5 trials advancing past early perioperative and cannula-related complications lasted the full month of support. Blood flow rate and CO2 removal in these trials were 2.1 ± 0.3 L/min and 139 ± 15 mL/min, respectively, and were stable during support. One trial ended after 22 days of support due to intradevice thrombosis. Support was well tolerated by the sheep with no signs of hemolysis or device-related organ impairment.

CONCLUSIONS

These results demonstrate the ability of the ModELAS to provide safe month-long support without consistent deterioration of pumping or gas exchange capabilities.