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

Mechanical ventilation during extracorporeal membrane oxygenation support - New trends and continuing challenges

BACKGROUND

The impact of mechanical ventilation on the survival of patients supported with veno-venous extracorporeal membrane oxygenation (V-V ECMO) due to severe acute respiratory distress syndrome (ARDS) remains still a focus of research.

METHODS

Recent guidelines, randomized trials, and registry data underscore the importance of lung-protective ventilation during respiratory and cardiac support on ECMO.

RESULTS

This approach includes decreasing mechanical power delivery by reducing tidal volume and driving pressure as much as possible, using low or very low respiratory rate, and a personalized approach to positive-end expiratory pressure (PEEP) setting. Notably, the use of ECMO in awake and spontaneously breathing patients is increasing, especially as a bridging strategy to lung transplantation. During respiratory support in V-V ECMO, native lung function is of highest importance and adjustments of blood flow on ECMO, or ventilator settings significantly impact the gas exchange. These interactions are more complex in veno-arterial (V-A) ECMO configuration and cardiac support. The fraction on delivered oxygen in the sweep gas and sweep gas flow rate, blood flow per minute, and oxygenator efficiency have an impact on gas exchange on device side. On the patient side, native cardiac output, native lung function, carbon dioxide production (VCO2), and oxygen consumption (VO2) play a role. Avoiding pulmonary oedema includes left ventricle (LV) distension monitoring and prevention, pulse pressure >10 mm Hg and aortic valve opening assessment, higher PEEP adjustment, use of vasodilators, ECMO flow adjustment according to the ejection fraction, moderate use of inotropes, diuretics, or venting strategies as indicated and according to local expertise and resources.

CONCLUSION

Understanding the physiological principles of gas exchange during cardiac support on femoro-femoral V-A ECMO configuration and the interactions with native gas exchange and haemodynamics are essential for the safe applications of these techniques in clinical practice. Proning during ECMO remains to be discussed until further data is available from prospective, randomized trials implementing individualized PEEP titration during proning.

Extracorporeal membrane oxygenation in obstetric patients: An Israeli nationwide study

BACKGROUND

The leading causes of maternal mortality include respiratory failure, cardiovascular events, infections, and hemorrhages. The use of extracorporeal membrane oxygenation (ECMO) as rescue therapy in the peripartum period for cardiopulmonary failure is expanding in critical care medicine.

METHODS

This retrospective observational study was conducted on a nationwide cohort in Israel. During the 3-year period, between September 1, 2019, and August 31, 2022, all women in the peripartum period who had been supported by ECMO for respiratory or circulatory failure at 10 large Israeli hospitals were identified. Indications for ECMO, maternal and neonatal outcomes, details of ECMO support, and complications were collected.

RESULTS

During the 3-year study period, in Israel, there were 540 234 live births, and 28 obstetric patients were supported by ECMO, with an incidence of 5.2 cases per 100 000 or 1 case per 19 000 births (when excluding patients with COVID-19, the incidence will be 2.5 cases per 100 000 births). Of these, 25 were during the postpartum period, of which 16 (64%) were connected in the PPD1, and 3 were during pregnancy. Eighteen patients (64.3%) were supported by V-V ECMO, 9 (32.1%) by V-A ECMO, and one (3.6%) by a VV-A configuration. Hypoxic respiratory failure (ARDS) was the most common indication for ECMO, observed in 21 patients (75%). COVID-19 was the cause of ARDS in 15 (53.7%) patients. The indications for the V-A configuration were cardiomyopathy (3 patients), amniotic fluid embolism (2 patients), sepsis, and pulmonary hypertension. The maternal and fetal survival rates were 89.3% (n = 25) and 100% (n = 28). The average ECMO duration was 17.6 ± 18.6 days and the ICU stay was 29.8 ± 23.8 days. Major bleeding complications requiring surgical intervention were observed in one patient.

CONCLUSIONS

The incidence of using ECMO in the peripartum period is low. The maternal and neonatal survival rates in patients treated with ECMO are high. These results show that ECMO remains an important treatment option for obstetric patients with respiratory and/or cardiopulmonary failure.

Clinical indications and outcomes of Impella devices for severe cardiogenic shock in COVID-19 patients: a systematic review

Background

Coronavirus disease 2019 (COVID-19) can present with significant cardiac dysfunction, including cardiogenic shock. Mechanical circulatory support with an Impella device may be utilized in these patients to support and offload native right ventricle (RV) and left ventricle (LV) functions. This systematic review aims to describe clinical indications, management, laboratory data, and outcomes in patients with severe cardiogenic shock from COVID-19 treated with an Impella device.

Methods

A PRISMA-directed systematic review was performed and prospectively registered in PROSPERO. The databases accessed included PubMed/MEDLINE, Scopus, and ScienceDirect. Quality and risk of bias assessments were completed using the Joanna Briggs Institute (JBI) checklist for case reports.

Results

A total of 16 records were included in the qualitative synthesis; 8/16 (50%) of the patients were men. The average age was 39 years (SD: 14.7). The biventricular Impella (BiPella) approach was recorded in 3/16 (18.75%) patients. A total of 4/16 (25%) individuals required renal replacement therapy (RRT). Single-device usage was observed in three cases: 2/16 Impella CP (12.5%) and 1/16 Impella RP (6.25%). Treatment of COVID-19 myocarditis included a wide range of antivirals and immunomodulators; 8/16 (50%) cases needed ECMO (extracorporeal membrane oxygenation) support. Overall, only 2/16 (11.7%) individuals died.

Conclusions

Sixteen reported individuals have received an Impella implanted with a mortality rate of 11.7%. Concurrent use of RRT and ECMO implantation was often observed. Overall, the Impella device is an effective and safe strategy in the management of COVID-19-related cardiogenic shock. Future studies should include long-term results.

Effects of adding the second drainage cannula in severely hypoxemic patients supported with VV ECMO due to COVID-19-associated ARDS

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a recognized method of support in patients with severe and refractory acute respiratory distress syndrome (ARDS) caused by SARS-CoV-2 infection. While veno-venous (VV) ECMO is the most common type, some patients with severe hypoxemia may require modifications to the ECMO circuit. In this study, we aimed to investigate the effects of adding a second drainage cannula to the circuit in patients with refractory hypoxemia, on their gas exchange, mechanical ventilation, ECMO settings, and clinical outcomes.

METHODS

We conducted an observational retrospective study based on a single-center institutional registry including all consecutive cases of COVID-19 patients requiring ECMO admitted to the Centre of Extracorporeal Therapies in Warsaw between March 1, 2020 and March 1, 2022. We selected patients who had an additional drainage cannula inserted. Changes in ECMO and ventilator settings, blood oxygenation, and hemodynamic parameters, as well as clinical outcomes were assessed.

RESULTS

Of 138 VV ECMO patients, 12 (9%) patients met the inclusion criteria. Ten patients (83%) were men, and mean age was 42.2 ± 6.8. An addition of drainage cannula resulted in a significant raise in ECMO blood flow (4.77 ± 0.44 to 5.94 ± 0.81 [L/min]; p = 0.001), and the ratio of ECMO blood flow to ECMO pump rotations per minute (RPM), whereas the raise in ECMO RPM alone was not statistically significant (3432 ± 258 to 3673 ± 340 [1/min]; p = 0.064). We observed a significant drop in ventilator FiO2 and a raise in PaO2 to FiO2 ratio, while blood lactates did not change significantly. Nine patients died in hospital, one was referred to lung transplantation center, two were discharged uneventfully.

CONCLUSIONS

The use of an additional drainage cannula in severe ARDS associated with COVID-19 allows for an increased ECMO blood flow and improved oxygenation. However, we observed no further improvement in lung-protective ventilation and poor survival.

Extracorporeal membrane oxygenation for COVID-19-related acute respiratory distress syndrome: a narrative review

A growing body of evidence supports the use of extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome (ARDS) refractory to maximal medical therapy. ARDS may develop in a proportion of patients hospitalized for coronavirus disease 2019 (COVID-19) and ECMO may be used to manage patients refractory to maximal medical therapy to mitigate the risk of ventilator-induced lung injury and provide lung rest while awaiting recovery. The mortality of COVID-19-related ARDS was variously reassessed during the pandemic. Veno-venous (VV) ECMO was the default choice to manage refractory respiratory failure; however, with concomitant severe right ventricular dysfunction, venoarterial (VA) ECMO or mechanical right ventricular assist devices with extracorporeal gas exchange (Oxy-RVAD) were also considered. ECMO has also been used to manage special populations such as pregnant women, pediatric patients affected by severe forms of COVID-19, and, in cases with persistent and seemingly irreversible respiratory failure, as a bridge to successful lung transplantation. In this narrative review, we outline and summarize the most recent evidence that has emerged on ECMO use in different patient populations with COVID-19-related ARDS.

In-hospital and 6-month outcomes in patients with COVID-19 supported with extracorporeal membrane oxygenation (EuroECMO-COVID): a multicentre, prospective observational study

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been widely used in patients with COVID-19, but uncertainty remains about the determinants of in-hospital mortality and data on post-discharge outcomes are scarce. The aims of this study were to investigate the variables associated with in-hospital outcomes in patients who received ECMO during the first wave of COVID-19 and to describe the status of patients 6 months after ECMO initiation.

METHODS

EuroECMO-COVID is a prospective, multicentre, observational study developed by the European Extracorporeal Life Support Organization. This study was based on data from patients aged 16 years or older who received ECMO support for refractory COVID-19 during the first wave of the pandemic-from March 1 to Sept 13, 2020-at 133 centres in 21 countries. In-hospital mortality and mortality 6 months after ECMO initiation were the primary outcomes. Mixed-Cox proportional hazards models were used to investigate associations between patient and management-related variables (eg, patient demographics, comorbidities, pre-ECMO status, and ECMO characteristics and complications) and in-hospital deaths. Survival status at 6 months was established through patient contact or institutional charts review. This study is registered with ClinicalTrials.gov, NCT04366921, and is ongoing.

FINDINGS

Between March 1 and Sept 13, 2020, 1215 patients (942 [78%] men and 267 [22%] women; median age 53 years [IQR 46-60]) were included in the study. Median ECMO duration was 15 days (IQR 8-27). 602 (50%) of 1215 patients died in hospital, and 852 (74%) patients had at least one complication. Multiorgan failure was the leading cause of death (192 [36%] of 528 patients who died with available data). In mixed-Cox analyses, age of 60 years or older, use of inotropes and vasopressors before ECMO initiation, chronic renal failure, and time from intubation to ECMO initiation of 4 days or more were associated with higher in-hospital mortality. 613 patients did not die in hospital, and 547 (95%) of 577 patients for whom data were available were alive at 6 months. 102 (24%) of 431 patients had returned to full-time work at 6 months, and 57 (13%) of 428 patients had returned to part-time work. At 6 months, respiratory rehabilitation was required in 88 (17%) of 522 patients with available data, and the most common residual symptoms included dyspnoea (185 [35%] of 523 patients) and cardiac (52 [10%] of 514 patients) or neurocognitive (66 [13%] of 512 patients) symptoms.

INTERPRETATION

Patient's age, timing of cannulation (<4 days vs ≥4 days from intubation), and use of inotropes and vasopressors are essential factors to consider when analysing the outcomes of patients receiving ECMO for COVID-19. Despite post-discharge survival being favourable, persisting long-term symptoms suggest that dedicated post-ECMO follow-up programmes are required.

FUNDING

None.

Extracorporeal life support provision in COVID-19 patients - An international EuroELSO 2022 update survey

INTRODUCTION

An analysis on the ECLS use for patients with respiratory or cardiac support in COVID-19 based on an international response to EuroELSO survey, aims to generate a more comprehensive understanding of ECLS role during the recent viral pandemic.

METHODS

EuroELSO announced the survey at the 10th annual congress in London, May 2022. The survey covered 26 multiple-choice questions.

RESULTS

The survey returned 69 questionnaires from 62 centers across 22 European countries and seven centers across five non-European countries. Most of the centers providing ECLS for COVID-19 patients had more than 30 runs for respiratory support since December 2019. In the same period, at least 31 runs in adult COVID-19 patients have been performed in 48 of 69 centers (69.6%). The reported pediatric data from 18 centers is limited to less than the patients per center.

CONCLUSION

Majority of the COVID-19 patients received respiratory ECLS support and adult patients dominated. The indications and contraindications are broadly aligned with available guidelines. Most of the centers considered age >65 or biological age as a relative or absolute contraindication for ECLS in COVID-19. ECLS withdrawal criteria in COVID-19 are controversial because the long-term outcomes after ECLS in COVID-19 and the impact of critical illness and the impact of long-COVID are still not known.

COVID-19 and Pulmonary Embolism Outcomes among Hospitalized Patients in the United States: A Propensity-Matched Analysis of National Inpatient Sample

Venous thromboembolism, in particular, pulmonary embolism (PE), is a significant contributor to the morbidity and mortality associated with COVID-19. In this study, we utilized the National Inpatient Sample (NIS) database 2020 to evaluate and compare clinical outcomes in patients with COVID-19 with and without PE. Our sample includes 1,659,040 patients hospitalized with COVID-19 pneumonia between January 2020 and December 2020. We performed propensity-matched analysis for patient characteristics and in-hospital outcomes, including the patient’s age, race, sex, insurance status, median income, length of stay, mortality, hospitalization cost, comorbidities, mechanical ventilation, and vasopressor support. Patients with COVID-19 with PE had a higher need for mechanical ventilation (25.7% vs. 15.6%, adjusted odds ratio 1.4, 95% CI 1.4−1.5, p < 0.001), the vasopressor requirement (5.4% vs. 2.6%, adjusted OR 1.6, 95% CI 1.4−1.8, p < 0.001), longer hospital stays (10.8 vs. 7.9 days, p < 0.001), and overall higher in-hospital mortality (19.1 vs. 13.9%, adjusted OR of 1.3, 95% CI 1.1−1.5, p < 0.001). This study highlights the need for more aggressive management of PE in COVID-19-positive patients with the aim to improve early diagnosis and treatment to reduce morbidity, mortality, and healthcare costs seen in the synchronous COVID-19 and PE-positive patients.

Coronavirus disease 2019 and mechanical circulatory support devices: A comprehensive review

Coronavirus disease (COVID-19) can cause circulatory shock refractory to medical therapy. Such patients can be managed with mechanical circulatory support (MCS) devices like IABP, Impella, VA ECMO, and Left Ventricular Assist Devices (LVADs). Moreover, patients on long-term durable LVADs are a special population having increased susceptibility and mortality to COVID-19 infection. In this narrative review, we searched PubMed and Medline for studies on COVID-19 patients on short-term MCS devices. We found 36 papers with 110 patients who met our review criteria, including 89 LVAD patients and 21 COVID-19 patients who needed MCS device therapy. These studies were used to extract patient demographics, clinical presentation, MCS device details, management, and outcomes. Mean age of patients with COVID-19 infection on LVADs was 60, 73% were male, and HeartMate 3 was the most common device (53%). Most patients (77.5%) needed hospitalization, and mortality was 23.6%. Among the 21 reported cases of critically ill COVID-19 patients who required MCS, the mean age was 49.8 years, 52% were women, and the most common MCS device used was VA ECMO (62%) in conjunction with an Impella for LV venting. Comorbidities were not present in 43%, but 71% had abnormal ventricular function on echocardiography. MCS is a viable option for managing severe COVID-19 infection with shock, with many reported cases of favorable outcomes.

Acute respiratory distress syndrome following coronary artery bypass grafting successfully treated with venovenous extracorporeal membrane oxygenation

Introduction. Acute respiratory distress syndrome (ARDS) is one of the most serious complications during the postoperative period in cardiac surgery. Venovenous extracorporeal membrane oxygenation (VV-ECMO) has proven to be a valuable therapy in ARDS when standard therapy is insufficient. Our aim is to present a case of severe ARDS which was succesfully treated by VV-ECMO. Case outline. A 54-year-old male patient was urgently admitted to our hospital due to anterior wall myocardal infarction. Urgent coronarography was performed, which found severe three-vessel coronary disease. Triple coronary artery bypass grafting (CABG) was performed. After surgery, due to prolonged respiratory insufficiency, the patient was diagnosed with ARDS and VV-ECMO was placed. Nine days later, normal values of gase exchange were achieved and the patient was succesfully weaned from VV-ECMO. Conclusion. We showed that when conventional therapy for ARDS is not effective, use of ECMO should be considered.