Neurological Complications of the Lower Extremities After Femoral Cannulated Extracorporeal Membrane Oxygenation: A Systematic Review

BACKGROUND

Femoral cannulated extracorporeal membrane oxygenation (ECMO) has been associated with neurologic complications in the lower extremity ipsilateral to the cannulation. There is uncertainty about the prevalence of these complications and their mechanisms of development.

OBJECTIVE

Aim of this systematic review was to investigate the prevalence of neurological complications after ECMO and to describe possible underlying mechanisms.

METHOD

A systematic literature search was performed in Medline-Ovid, Embase, Cochrane Library, CINAHL, and PEDro until April 2021 for clinical trials in English or German language which quantified neurologic complications in the lower extremity ipsilateral to the ECMO cannulation of adults. The complications had to be delimitable to intensive care unit-acquired weakness. Methodological quality was assessed by 2 independent investigators using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies of the National Heart, Lung, and Blood Institute.

RESULTS

Eight observational studies were included in the synthesis. Study quality was good to fair in 88% of the papers. Overall, 47 of 202 patients (23.3%; ranging from 3% to 48% across studies) with femoral ECMO cannulation showed neurologic complications of the lower extremity ipsilateral to the cannulation. Peripheral ischemia and compression of nerves by the ECMO cannula are discussed as mechanisms of injury.

CONCLUSION

The occurrence of neurological complications after ECMO was common and can lead to long-term impairment. The mechanisms are largely unknown but currently there is no sufficient evidence for the involvement of ECMO. Standardized assessments are needed to systematically screen for neurological complications early after ECMO, to enable countermeasures and prevent further complications.

ECMO aggravates platelet GPV shedding and δ-granule deficiency in COVID-19-associated acute respiratory distress syndrome

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a lifesaving therapy in patients with acute respiratory distress syndrome (ARDS). Hemostatic complications are frequently observed on ECMO and limit the success of this therapy. Platelets are key mediators of hemostasis enabling activation, aggregation and thrombus formation to exposed matrix proteins via their surface receptors such as glycoprotein (GP)VI or GPIb/V/IX. Recent research has elucidated a regulatory role of the GPV subunit. The cleaved soluble (s)GPV ectodomain was identified to spatio-temporally control fibrin formation through complex formation with thrombin.

OBJECTIVES

We aimed to decipher the impact of ECMO on platelet phenotype and function, including the role of GPV and plasmatic sGPV.

PATIENTS/METHODS

We recruited 36 patients with ARDS in the wake of coronavirus disease 2019 (COVID-19) pneumonia and performed a longitudinal comparison of platelet phenotype and function in non-ECMO (n=23) versus ECMO (n=13) compared to healthy controls. Patients were assessed at up to three time points (t1=day 1-3; t2=day 4-6; t3=day 7-14 after cannulation/study inclusion).

RESULTS

Agonist-induced platelet activation was assessed by flow cytometry and revealed decreased GPIIb/IIIa activation and α-granule release in all ARDS patients. During ECMO treatment, agonist-induced δ-granule release continuously decreased, which was independently confirmed by electron microscopy and associated with a prolonged in vitro bleeding time. GPV expression on the platelet surface markedly decreased in ECMO compared to non-ECMO patients. Plasma sGPV levels were increased in ECMO patients and associated with poor outcome.

CONCLUSIONS

Our data demonstrate an ECMO-intrinsic platelet δ-granule deficiency and hemostatic dysfunction beyond the underlying ARDS.

Prognostic factors in lung transplantation after extracorporeal membrane oxygenation bridging therapy: a systematic review and meta-analysis

Background

Extracorporeal membrane oxygenation (ECMO) has recently emerged as a critical support system for lung function in patients awaiting lung transplantation. This meta-analysis investigates the prognostic factors of lung transplantation following ECMO bridging therapy.

Methods

A comprehensive search was conducted in PubMed, Cochrane Library, Embase, CINAHL, Web of Science, Scopus, and ProQuest databases from inception to August 11, 2023. Included were cohort or case-control studies focusing on prognostic factors of lung transplantation with ECMO bridging therapy. Data extraction was performed independently, and study quality was assessed. A meta-analysis was carried out using RevMan 5.4 and Stata17.0 software to aggregate mortality rates and pertinent prognostic factors of ECMO as a bridge to lung transplantation.

Results

The search identified eight trials encompassing 1,086 participants. The prognosis of patients undergoing lung transplantation with ECMO bridging was significantly associated with several factors: prolonged ECMO support [odds ratio 1.07, 95% confidence interval (CI): 1.02-1.12, I2=77%], deterioration in liver and kidney function (odds ratio 3.62, 95% CI: 2.37-5.54, I2=0%), and complications during ECMO (odds ratio 2.24, 95% CI: 1.45-3.44, I2=5%).

Conclusions

Prolonged ECMO support, declining liver and kidney functions, and complications during ECMO are vital prognostic factors in lung transplantation following ECMO bridging therapy.

Comparative Analysis of Therapeutic Strategies in Post-Cardiotomy Cardiogenic Shock: Insight into a High-Volume Cardiac Surgery Center

Background: Post-cardiotomy cardiogenic shock (PCCS), which is defined as severe low cardiac output syndrome after cardiac surgery, has a mortality rate of up to 90%. No study has yet been performed to compare patients with PCCS treated by conservative means to patients receiving additional mechanical circulatory support with veno-arterial extracorporeal membrane oxygenation (ECMO). Methods: A single-center retrospective analysis from January 2018 to June 2022 was performed. Results: Out of 7028 patients who underwent cardiac surgery during this time period, 220 patients (3%) developed PCCS. The patients were stratified according to their severity of shock based on the Stage Classification Expert Consensus (SCAI) group. Known risk factors for shock-related mortality, including the vasoactive-inotropic score (VIS) and plasma lactate levels, were assessed at structured intervals. In patients treated additionally with ECMO (n = 73), the in-hospital mortality rate was 60%, compared to an in-hospital mortality rate of 85% in patients treated by conservative means (non-ECMO; n = 52). In 18/73 (25%) ECMO patients, the plasma lactate level normalized within 48 h, compared to 2/52 (4%) in non-ECMO patients. The morbidity of non-ECMO patients compared to ECMO patients included a need for dialysis (42% vs. 60%), myocardial infarction (19% vs. 27%), and cerebrovascular accident (17% vs. 12%). Conclusions: In conclusion, the additional use of ECMO in PCCS holds promise for enhancing outcomes in these critically ill patients, more rapid improvement of end-organ perfusion, and the normalization of plasma lactate levels.

Analysis of Vancomycin Dosage and Plasma Levels in Critically Ill Adult Patients Requiring Extracorporeal Membrane Oxygenation (ECMO)

Introduction: Critically ill patients undergoing extracorporeal membrane oxygenation (ECMO) exhibit unique pharmacokinetics. This study aimed to assess the achievement of vancomycin therapeutic targets in these patients. Methods: This retrospective cohort study included patients on ECMO treated with vancomycin between January 2010 and December 2018. Ninety patients were analyzed based on ECMO connection modality, baseline creatinine levels, estimated glomerular filtration rate (eGFR), renal replacement therapy (RRT) requirements, and vancomycin loading dose administration. Results: Twenty-three percent of the patients achieved the therapeutic range defined by baseline levels. No significant differences in meeting the therapeutic goal were found in multivariate analysis considering ECMO cannulation modality, initial creatinine level, initial eGFR, RRT requirement, or loading dose use. All trough levels between 15 and 20 mcg/mL achieved an estimated area under the curve/minimum inhibitory concentration (AUC/MIC) between 400 and 600, almost all trough levels over 10 mcg/mL predicted an AUC/MIC >400. Discussion: Achieving therapeutic plasma levels in these patients remains challenging, potentially due to factors such as individual pharmacokinetics and pathophysiology. A trough plasma level between 12 and 20 estimated the therapeutic AUC/MIC for all models, proposing a possible lower target, maintaining exposure, and potentially avoiding adverse effects. Despite being one of the largest cohorts of vancomycin use in ECMO patients studied, its retrospective nature and single-center focus limits its broad applicability.

Prognostic implication of Vasoactive Inotropic Score in adult patients with cardiogenic shock on veno-arterial extracorporeal membrane oxygenation

Background

Vasopressors and inotropes are crucial in managing cardiogenic shock (CS) as they enhance microcirculation in patients. Numerous studies have demonstrated the adverse outcomes associated with excessive use of vasoactive drugs and the vasoactive drug scoring system has emerged as a valuable prognostic tool, particularly in pediatric patients. This study aimed to examine the prognostic significance of the Vasoactive Inotropic Score (VIS) in adult patients with CS receiving veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment.

Methods

This retrospective multi-center study involved 2,453 adult patients who underwent VA-ECMO in China between 2015 and 2021. Among them, 1,742 adult patients with CS following VA-ECMO were finally included. The maximum VIS (VISmax) was determined by considering the highest doses of vasoactive and inotropic drugs administered within the first 6 hours before ECMO initiation. Based on the VISmax, patients were classified into two groups: 0-20 and >20. The primary outcome of this study was in-hospital mortality.

Results

A total of 1,146 patients were included in the high VISmax group, while 596 patients were assigned to the low VISmax group. Overall, 882 (50.6%) patients experienced in-hospital mortality, with significantly higher rates observed among those with higher VISmax scores (41.4% for VIS ≤20 versus 68.3% for VIS >20; P<0.001). Similar trends were observed for 30-day mortality (40.7% for VIS ≤20 versus 64.9% for VIS >20; P<0.001). Multivariable regression analysis demonstrated that a VIS score exceeding 20 independently predicted in-hospital mortality [odds ratio (OR) 2.64; 95% confidence interval (CI): 2.10-3.33; P<0.001]. The receiver operating characteristic (ROC) analysis revealed that VIS had an area under the curve (AUC) of 0.65 (95% CI: 0.63-0.68; P<0.001) as a predictor of in-hospital mortality, with an optimal cutoff value of 20.1. Moreover, the VIS exhibited good predictive ability for in-hospital mortality in patients with acute myocarditis (AUC 0.70; 95% CI: 0.63-0.78; P<0.001).

Conclusions

Firstly, higher maximum level of VIS within the first 6 hours before ECMO initiation independently predicted poorer clinical outcomes in patients supported with ECMO for CS. Secondly, VIS exceeding 20 was significantly associated with increased risks of in-hospital mortality and 30-day mortality. Thirdly, when categorized by the cause of CS, a high VIS exhibited good predictive ability in patients with acute myocardial infarction, heart failure, and acute myocarditis.

Effect of prone positioning on survival in adult patients receiving venovenous extracorporeal membrane oxygenation for acute respiratory distress syndrome: a prospective multicenter randomized controlled study

Background

Current data supporting the use of prone positioning (PP) during venovenous extracorporeal membrane oxygenation (VV-ECMO) in patients with acute respiratory distress syndrome (ARDS) are limited. This prospective randomized controlled study aimed to determine whether PP implemented within 24 hours of ECMO can improve survival in these patients.

Methods

From June 2021 to July 2023, 97 adult patients receiving VV-ECMO for ARDS in three centers were enrolled and 1:1 randomized into PP (n=49) and control groups (n=48). Patients in the PP group receiving prone positioning, while the control group were maintained in the supine position. The primary outcome was 30-day survival, and secondary outcomes included in-hospital survival and other clinical outcomes.

Results

All 97 patients were included for analysis. Patient characteristics did not significantly differ between the two groups. The median duration of PP was 81 hours, and the median number of PP sessions was 5 times. PP improved oxygenation and ventilator parameters. The incidence of complications during PP was low, with pressure sores being the most frequent (10.2%). The 30-day survival was significantly higher in the PP group (67.3% vs. 45.8%; P=0.033), as was in-hospital survival (61.2% vs. 39.6%; P=0.033). In the PP group, the successful ECMO weaning rate was significantly higher (77.5% vs. 50.0%; P=0.005), and the duration of ECMO support was significantly shorter {10 [8-11] vs. 10 [8-14] days; P=0.038}. However, in subgroup analysis of COVID patients the 30-day survival, in-hospital survival, successful ECMO weaning rate and the duration of ECMO support did not differ between the groups. The duration of mechanical ventilation, length of intensive care unit stay, and length of hospital stay did not significantly differ between the groups.

Conclusions

When initiated within 24 hours of ECMO, PP can improve 30-day survival in patients with ARDS receiving VV-ECMO. In addition, it may improve the successful ECMO weaning rate and reduce the duration of ECMO support. However, considering the limitations, more strictly designed, large sample prospective randomized controlled trials are proposed.

Trial Registration

Chinese Clinical Trial Registry ChiCTR2300075326.

Venovenous Extracorporeal Membrane Oxygenation Candidacy Decision-Making: Lessons and Hypotheses From a Single-Center Observational Analysis

BACKGROUND

Use of venovenous extracorporeal membrane oxygenation (ECMO) is increasing, but candidacy selection processes are variable and subject to bias.

RESEARCH QUESTION

What are the reasons behind venovenous ECMO candidacy decisions, and are decisions made consistently across patients?

STUDY DESIGN AND METHODS

Prospective observational study of all patients, admitted or outside hospital referrals, considered for venovenous ECMO at a tertiary referral center. Relevant clinical data and reasons for candidacy determination were cross-referenced with other noncandidates and candidates and were assessed qualitatively.

RESULTS

Eighty-one consultations resulted in 44 noncandidates (54%), 29 candidates (36%; nine of whom subsequently underwent cannulation), and eight deferred decisions (10%). Fifteen unique contraindications were identified, variably present across all patients. Five contraindications were invoked as the sole reason to deny ECMO to a patient. In patients with three or more contraindications, additional contraindications were cited even if the severity was relatively minor. All but four contraindications invoked to deny ECMO to a patient were nonprohibitive for at least one other candidate. Contraindications documented in noncandidates were present but not mentioned in 21 other noncandidates (47%). Twenty-six candidates (90%) had at least one contraindication that was prohibitive in a noncandidate, including a contraindication that was the sole reason to deny ECMO. Contraindications were proposed as informing three prognostic domains, through which patterns of inconsistency could be understood better: (1) irreversible underlying pulmonary process, (2) unsurvivable critical illness, and (3) clinical condition too compromised for meaningful recovery.

INTERPRETATION

ECMO candidacy decisions are inconsistent. We identified four patterns of inconsistency in our center and propose a three-domain model for understanding and categorizing contraindications, yielding five lessons that may improve candidacy decision processes until further research can guide practice more definitively.

Neutrophil extracellular traps - a potential trigger for the development of thrombocytopenia during extracorporeal membrane oxygenation

Neutrophil extracellular traps (NETs) have recently emerged as a potential link between inflammation, immunity, and thrombosis, as well as other coagulation disorders which present a major challenge in the context of extracorporeal membrane oxygenation (ECMO). By examining blood from ECMO patients for NETs and their precursors and correlating them with clinical and laboratory biomarkers of coagulation and inflammation, this study aims to evaluate the association between the presence of NETs in the bloodstream of ECMO patients and the development of potentially severe coagulation disorders during ECMO therapy. Therefore, blood samples were collected from healthy volunteers (n=13) and patients receiving veno-venous (VV) ECMO therapy (n=10). To identify NETs and their precursors, DNA and myeloperoxidase as well as granulocyte marker CD66b were visualized simultaneously by immunofluorescence staining in serial blood smears. Differentiation of DNA-containing objects and identification of NETs and their precursors was performed semiautomatically by a specific algorithm using the shape and size of DNA staining and the intensity of MPO and CD66b signal. Neutrophil extracellular traps and their precursors could be detected in blood smears from patients requiring VV ECMO. Compared to volunteers, ECMO patients presented significantly higher rates of NETs and NET precursors as well as an increased proportion of neutrophil granulocytes in all detected nucleated cells. A high NET rate prior to the initiation of ECMO therapy was associated with both increased IL-6 and TNF-α levels as an expression of a high cytokine burden. These patients with increased NET release also presented an earlier and significantly more pronounced decrease in platelet counts and ATIII activity following initiation of therapy compared with patients with less elevated NETs. These findings provide further indications for the development of immune-mediated acquired thrombocytopenia in ECMO patients.

Perioperative extracorporeal membrane oxygenation support for pulmonary endarterectomy: A 17-year experience from the UK national cohort

BACKGROUND

Pulmonary endarterectomy (PEA) is the guideline-recommended treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH). However, some patients develop severe cardiopulmonary compromise before surgery, intraoperatively, or early postoperatively. This may result from advanced CTEPH, reperfusion pulmonary edema, massive endobronchial bleeding, or right ventricular (RV) failure secondary to residual pulmonary hypertension. Conventional cardiorespiratory support is ineffective when these complications are severe. Since 2005, we used extracorporeal membrane oxygenation (ECMO) as a rescue therapy for this group. We review our experience with ECMO support in these patients.

METHODS

This study was a retrospective analysis of patients who received perioperative ECMO for PEA from a single national center from August 2005 to July 2022. Data were prospectively collected.

RESULTS

One hundred and ten patients (4.7%) had extreme cardiorespiratory compromise requiring perioperative ECMO. Nine were established on ECMO before PEA. Of those who received ECMO postoperatively, 39 were for refractory reperfusion lung injury, 20 for RV failure, 31 for endobronchial bleeding, and the remaining 11 were for "other" reasons, such as cardiopulmonary resuscitation following late tamponade and aspiration pneumonitis. Sixty-two (56.4%) were successfully weaned from ECMO. Fifty-seven patients left the hospital alive, giving a salvage rate of 51.8%. Distal disease (Jamieson Type III) and significant residual pulmonary hypertension were also predictors of mortality on ECMO support. Overall, 5- and 10-year survival in patients who were discharged alive following ECMO support was 73.9% (SE: 6.1%) and 58.2% (SE: 9.5%), respectively.

CONCLUSIONS

Perioperative ECMO support has an appropriate role as rescue therapy for this group. Over 50% survived to hospital discharge. These patients had satisfactory longer-term survival.

Ambulatory 7-day mechanical circulatory support in sheep model of pulmonary hypertension and right heart failure

BACKGROUND

Right heart failure is the major cause of death in pulmonary hypertension. Lung transplantation is the only long-term treatment option for patients who fail medical therapy. Due to the scarcity of donor lungs, there is a critical need to develop durable mechanical support for the failing right heart. A major design goal for durable support is to reduce the size and complexity of devices to facilitate ambulation. Toward this end, we sought to deploy wearable mechanical support technology in a sheep disease model of chronic right heart failure.

METHODS

In 6 sheep with chronic right heart failure, a mechanical support system consisting of an extracorporeal blood pump coupled with a gas exchange unit was attached in a right atrium-to-left atrium configuration for up to 7 days. Circuit performance, hematologic parameters, and animal hemodynamics were analyzed.

RESULTS

Six subjects underwent the chronic disease model for 56 to 71 days. Three of the subjects survived to the 7-day end-point for circulatory support. The circuit provided 2.8 (0.5) liter/min of flow compared to the native pulmonary blood flow of 3.5 (1.1) liter/min. The animals maintained physiologically balanced blood gas profile with a sweep flow of 1.2 (1.0) liter/min. Two animals freely ambulated while wearing the circuit.

CONCLUSIONS

Our novel mechanical support system provided physiologic support for a large animal model of pulmonary hypertension with right heart failure. The small footprint of the circuit and the low sweep requirement demonstrate the feasibility of this technology to enable mobile ambulatory applications.

"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.

In-hospital care of children with COVID-19

Children have been reported to be less affected and to have milder severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection than adults during the coronavirus disease 2019 (COVID-19) pandemic. However, children, and particularly those with underlying disorders, are still likely to develop critical illnesses. In the case of SARS-CoV-2 infection, most previous studies have focused on adult patients. To aid in the knowledge of in-hospital care of children with COVID-19, this study presents an expert review of the literature, including the management of respiratory distress or failure, extracorporeal membrane oxygenation (ECMO), multisystem inflammatory syndrome in children (MIS-C), hemodynamic and other organ support, pharmaceutical therapies (anti-viral drugs, anti-inflammatory or antithrombotic therapies) and management of cardiopulmonary arrest.

Possible Involvement of Protein Binding Inhibition in Changes in Dexmedetomidine Concentration in Extracorporeal Circuits during Midazolam Use

It was recently reported that the dexmedetomidine concentration within the extracorporeal circuit decreases with co-administration of midazolam. In this study, we investigated whether displacement of dexmedetomidine by midazolam from the binding site of major plasma proteins, human serum albumin (HSA) and α1-acid glycoprotein (AAG), would increase levels of free dexmedetomidine that could be adsorbed to the circuit. Equilibrium dialysis experiments indicated that dexmedetomidine binds to a single site on both HSA and AAG with four times greater affinity than midazolam. Midazolam-mediated inhibition of the binding of dexmedetomidine to HSA and AAG was also examined. The binding of dexmedetomidine to these proteins decreased in the presence of midazolam. Competitive binding experiments suggested that the inhibition of binding by midazolam was due to competitive displacement at site II of HSA and due to non-competitive displacement at the site of AAG. Thus, our present data indicate that free dexmedetomidine displaced by midazolam from site II of HSA or from AAG is adsorbed onto extracorporeal circuits, resulting in a change in the dexmedetomidine concentration within the circuit.

Cardiogenic shock in pregnancy

Cardiac disease complicates 1%-4% of pregnancies globally, with a predominance in low and middle-income countries (LMICs). Increasing maternal age, rates of obesity, cardiovascular comorbidities, pre-eclampsia and gestational diabetes all contribute to acquired cardiovascular disease in pregnancy. Additionally, improved survival in congenital heart disease (CHD) has led to increasing numbers of women with CHD undergoing pregnancy. Implementation of individualised care plans formulated through pre-conception counselling and based on national and international guidance have contributed to improved clinical outcomes. However, there remains a significant proportion of women of reproductive age with no apparent comorbidities or risk factors that develop heart disease during pregnancy, with no indication for pre-conception counselling. The most extreme manifestation of cardiac disease is cardiogenic shock (CS), where the primary cardiac pathology results in inadequate cardiac output and hypoperfusion, and is associated with significant mortality and morbidity. Key to management is early recognition, intervention to treat any potentially reversible underlying pathology and supportive measures, up to and including mechanical circulatory support (MCS). In this narrative review we discuss recent developments in the classification of CS, and how these may be adapted to improve outcomes of pregnant women with, or at risk of developing, this potentially lethal condition.

Using Signal Features of Functional Near-Infrared Spectroscopy for Acute Physiological Score Estimation in ECMO Patients

Extracorporeal membrane oxygenation (ECMO) is a vital emergency procedure providing respiratory and circulatory support to critically ill patients, especially those with compromised cardiopulmonary function. Its use has grown due to technological advances and clinical demand. Prolonged ECMO usage can lead to complications, necessitating the timely assessment of peripheral microcirculation for an accurate physiological evaluation. This study utilizes non-invasive near-infrared spectroscopy (NIRS) to monitor knee-level microcirculation in ECMO patients. After processing oxygenation data, machine learning distinguishes high and low disease severity in the veno-venous (VV-ECMO) and veno-arterial (VA-ECMO) groups, with two clinical parameters enhancing the model performance. Both ECMO modes show promise in the clinical severity diagnosis. The research further explores statistical correlations between the oxygenation data and disease severity in diverse physiological conditions, revealing moderate correlations with the acute physiologic and chronic health evaluation (APACHE II) scores in the VV-ECMO and VA-ECMO groups. NIRS holds the potential for assessing patient condition improvements.

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.

Early application of awake extracorporeal membrane oxygenation in pneumocystis jirovecii pneumonia complicated with severe acute respiratory distress syndrome: a case report

Introduction

Patients suffering from severe acute respiratory distress syndrome (ARDS) are usually treated with mechanical ventilation. Extracorporeal membrane oxygenation (ECMO) has traditionally been considered a life-saving therapy and was reserved as a last resort when other treatment options were exhausted. However, this report outlines our successful initial experience with early implementation of awake venovenous extracorporeal membrane oxygenation (VV-ECMO) in a case of pneumocystis jirovecii pneumonia complicated by severe acute respiratory distress syndrome (ARDS), offering a promising new approach for recovery.

Case presentation

We present a case report of the effective application of awake VV-ECMO in a 29 years-old man with severe ARDS caused by pneumocystis jirovecii pneumonia. The patient initially received antibiotic treatment and non-invasive ventilation (NIV) for respiratory distress, but these interventions failed to improve the worsening dyspnea that occurred in the patient. Following the combined antifungal therapy, high-flow nasal cannula (HFNC) oxygen therapy, and VV-ECMO for a duration of 7 days, the patient's symptoms improved, showing relief.

Conclusion

Awake VV-ECMO proved to be an effective treatment for critically ill patients with ARDS, avoiding the need for invasive mechanical ventilation. However, increased clinical evidence is needed to verify whether awake ECMO could be widely used in severe ARDS caused by other diseases or conditions.

Extracorporeal life support as a bridge to lung transplantation: a narrative review

Background and Objective

The utilization of extracorporeal life support (ECLS) as a bridge to lung transplantation (LTx) has rapidly expanded over recent years in highly urgent patients even though the reported outcomes in current literature are still divergent. The aim of our narrative review was to provide a comprehensive picture on the peri and post-operative outcomes of patients bridged to LTx with this device from the most updated literature in the field.

Methods

The literature about ECLS bridge to LTx was searched on PubMed using a formal strategy. We focused our research on studies published between 2015 and 2022 and in English language. Abstracts, case reports, conference presentations, editorials, expert opinions and review articles were excluded.

Key Content and Findings

ECLS has emerged as a valid tool to bridge critically ill patients to LTx. Some issues, like the selection of candidates and the post-operative outcomes, are still matter of debate in the current reported series. We analyzed 14 papers published in the last seven years and with at least 20 patients to provide an updated overview on this topic. We found that, in highly experienced centers, ECLS can be used as a good strategy to allow critically ill patients to remain eligible to LTx with satisfying post-operative outcomes.

Conclusions

Specific scores and algorithms should be implemented to improve the selection process of candidates who could benefit more from ECLS as a bridge to LTx. Ambulatory/awake ECLS strategies should be always preferred to enroll patients in active rehabilitation programs awaiting LTx, improving short and long-term outcomes and increasing the success of LTx.

The role of extracorporeal life support in extended lung resections for non-small cell lung cancer: a narrative review

Background and Objective

Extracorporeal membrane oxygenation (ECMO) may be used as a substitute of traditional cardiopulmonary bypass (CPB) in thoracic surgeries. Extended resections for the treatment of non-small cell lung cancer (NSCLC) occasionally require extracorporeal life support. We present a narrative review of the current clinical uses of extracorporeal devices in this setting of patients.

Methods

We searched Medline database/PubMed for "extra-corporeal membrane oxygenation" and "non-small cell lung carcinoma" in the English language literature between the years 2000 and 2022.

Key Content and Findings

As opposed to CPB, ECMO is simple, requires minimal or no anticoagulation and elicits fewer complications. T4 lung cancers are frequently considered for surgery in marginally operable patients. ECMO may provide the means to achieve these resections. There are case series of carinal extended resections safely performed under venovenous (VV) or venoarterial (VA) support. The main advantages are a clear surgical field, certainty of proper oxygenation and avoidance of ventilator induced trauma. Left atrial resections have been described with VA ECMO, but the standard of care is still CPB. Descending thoracic aorta resections can also benefit from extracorporeal support, making sure that abdominal organs and lower limbs are well perfused, the heart is not overloaded, and cross clamping is safe.

Conclusions

Surgeons performing extended lung cancer resections should be familiar with ECMO and are encouraged to report their experience.

Extracorporeal life support use in limited lung function: a narrative review

Background and Objective

In thoracic surgery, different modalities of extracorporeal life support (ECLS) can be used for cardiorespiratory support in complex scenarios. Decades of learning in clinical practice and physiology associated with technological development led to a great variety of ECLS technologies available. Thoracic surgery procedures with difficult or impossible single lung ventilation may still be performed using different ECLS modalities. The aim of this review is to describe the use of ECLS, with its different modalities, as a solution to perform complex surgeries in a patient with difficult or impossible single lung ventilation.

Methods

A literature review was conducted using the terms "extracorporeal life support pulmonary resection" and "extracorporeal life support thoracic surgery", and articles were selected according to defined criteria.

Key Content and Findings

To support lung function during thoracic surgery, the most efficient and popular variety of ECLS is venovenous extracorporeal membrane oxygenation. Lung resection on a single lung after pneumonectomy, surgery in a patient with severe hypercapnia and/or low respiratory reserve, carinal and airway surgery, and severe thoracic trauma are the main examples of situations where ECLS may be the solution to provide a safe surgical environment in patients who cannot tolerate single lung ventilation. Multidisciplinarity, selection of patients and careful surgical planning are cornerstones in defining the situations that may benefit from ECLS support.

Conclusions

Knowledge on techniques of ECLS are essential for every thoracic surgeon. Although rarely used, these techniques of cardiorespiratory support should be considered when planning complex cases with difficulties in ventilation and emergent situations.

Impact of intraoperative use of venovenous extracorporeal membrane oxygenation on the status of von Willebrand factor large multimers during single lung transplantation

Background

von Willebrand factors (vWFs), hemostatic factors, are produced as large multimers and are shear stress-dependently cleaved to become the appropriate size. A reduction in vWF large multimers develops in various conditions including the use of extracorporeal life support, which can cause excessive-high shear stress in the blood flow and result in hemostatic disorders. The objective of this prospective study was to investigate the impact of venovenous extracorporeal membrane oxygenation (VV ECMO) use on the status of vWF large multimers and hemostatic disorders during single lung transplantation (SLT).

Methods

We prospectively enrolled 12 patients who underwent SLT at our center. Among them, seven patients were supported by VV ECMO intraoperatively (ECMO group) and the remaining five patients underwent SLT without ECMO support (control group). The vWF large multimer index (%) was defined as the ratio of the large multimer proportion in total vWF (vWF large multimer ratio) derived from a patient's plasma to that from standard human plasma.

Results

The vWF large multimer index at the end of the surgery was significantly lower in the ECMO group than in the control group (112.6% vs. 75.8%, respectively; P<0.05). The intraoperative blood loss and the amounts of intraoperative transfusion products in the ECMO group tended to be greater than those in the control group; however, the differences were not significant.

Conclusions

During SLT, the use of VV ECMO caused a decrease in the vWF large multimer index. The short duration of time of VV ECMO use in our study did not significantly affect the intra- and postoperative outcomes including blood loss, blood transfusion, and re-exploration thoracotomy for bleeding. Nevertheless, to comprehensively evaluate the actual influence of this decrease in the vWF large multimer index on intra- and postoperative outcomes, a multicenter larger-scale study is warranted.

Extracorporeal Membrane Oxygenation (VA-ECMO) in Management of Cardiogenic Shock

Cardiogenic shock is a critical condition of low cardiac output resulting in insufficient systemic perfusion and end-organ dysfunction. Though significant advances have been achieved in reperfusion therapy and mechanical circulatory support, cardiogenic shock continues to be a life-threatening condition associated with a high rate of complications and excessively high patient mortality, reported to be between 35% and 50%. Extracorporeal membrane oxygenation can provide full cardiopulmonary support, has been increasingly used in the last two decades, and can be used to restore systemic end-organ hypoperfusion. However, a paucity of randomized controlled trials in combination with high complication and mortality rates suggest the need for more research to better define its efficacy, safety, and optimal patient selection. In this review, we provide an updated review on VA-ECMO, with an emphasis on its application in cardiogenic shock, including indications and contraindications, expected hemodynamic and echocardiographic findings, recommendations for weaning, complications, and outcomes. Furthermore, specific emphasis will be devoted to the two published randomized controlled trials recently presented in this setting.

Cardiac dysfunction in severe pediatric acute respiratory distress syndrome: the right ventricle in search of the right therapy

Severe acute respiratory distress syndrome in children, or PARDS, carries a high risk of morbidity and mortality that is not fully explained by PARDS severity alone. Right ventricular (RV) dysfunction can be an insidious and often under-recognized complication of severe PARDS that may contribute to its untoward outcomes. Indeed, recent evidence suggest significantly worse outcomes in children who develop RV failure in their course of PARDS. However, in this narrative review, we highlight the dearth of evidence regarding the incidence of and risk factors for PARDS-associated RV dysfunction. While we wish to draw attention to the absence of available evidence that would inform recommendations around surveillance and treatment of RV dysfunction during severe PARDS, we leverage available evidence to glean insights into potentially helpful surveillance strategies and therapeutic approaches.

Long-Term Outcomes of Extracorporeal Life Support in Respiratory Failure

Although extracorporeal life support is an expensive method with serious risks of complications, it is nowadays a well-established and generally accepted method of organ support. In patients with severe respiratory failure, when conventional mechanical ventilation cannot ensure adequate blood gas exchange, veno-venous extracorporeal membrane oxygenation (ECMO) is the method of choice. An improvement in oxygenation or normalization of acid-base balance by itself does not necessarily mean an improvement in the outcome but allows us to prevent potential negative effects of mechanical ventilation, which can be considered a crucial part of complex care leading potentially to an improvement in the outcome. The disconnection from ECMO or discharge from the intensive care unit should not be viewed as the main goal, and the long-term outcome of the ECMO-surviving patients should also be considered. Approximately three-quarters of patients survive the veno-venous ECMO, but various (both physical and psychological) health problems may persist. Despite these, a large proportion of these patients are eventually able to return to everyday life with relatively little limitation of respiratory function. In this review, we summarize the available knowledge on long-term mortality and quality of life of ECMO patients with respiratory failure.

Management of primary graft dysfunction after lung transplantation with extracorporeal life support: an evidence-based review

Primary graft dysfunction (PGD) is a complex inflammatory syndrome that can lead to respiratory failure after lung transplantation (LTx). The pathogenesis of PGD is multifactorial and can be driven by attributes of both the donor and recipient, perioperative characteristics, and technical handling of the graft. Despite significant advancements in patient and donor selection, perioperative management and surgical technique, PGD is still a major contributor to morbidity and mortality after lung transplant. Although there are no known durable treatment options for PGD after LTx, an increasing body of evidence and experience in high-volume lung transplant centers show that extracorporeal life support (ECLS) is a reliable option for both preventing PGD and supporting critically ill patients with PGD. Both veno-venous (V-V) ECLS and veno-arterial (V-A) ECLS are proven and feasible strategies for mitigating the morbidity and mortality associated with post-LTx PGD. In this evidence-based review, we provide an overview of the epidemiology and physiology of PGD as well as a growing body of data that supports ECLS as a major tool to manage PGD. We describe the role of ECMO in PGD prevention and management, worldwide outcomes of LTx with ECLS support, and outline our step-wise approach to managing this complex respiratory syndrome leading up to institution of ECLS.

Current use of extracorporeal life support in airway surgery: a narrative review

BACKGROUND AND OBJECTIVE

Extracorporeal life support (ECLS) is widely used in patients with severe respiratory or cardiocirculatory failure. The most commonly used extracorporeal membrane oxygenation (ECMO) modes are veno-venous (V-V) and veno-arterial (V-A) ECMO, which can both be achieved by various types of vascular cannulation. Within the scope of tracheobronchial surgery, intraoperative ECLS may occasionally be necessary to provide sufficient oxygenation to a patient throughout a procedure, especially when conventional ventilation strategies are limited. Additionally, V-A ECMO can provide cardiopulmonary support in emergencies and in cases where hemodynamic instability can occur.

METHODS

This narrative literature review was carried out to identify the use and the specifics of ECLS in airway surgery over the last years. Data from 168 cases were summarized according to the indication for surgery and the mode of ECLS (V-V, V-A).

KEY CONTENT AND FINDINGS

The most common tracheobronchial pathologies in which support was needed were: primary malignant disease of the airways, malignant infiltration, tracheal stenosis, injury of the airway, and congenital airway disease. With increasing experience in ECLS, the number of reported cases performed with intraoperative ECLS increased steadily over the last decade.

CONCLUSIONS

A trend favoring the use of V-V ECMO over V-A ECMO was identified. These approaches should now be considered indispensable tools for managing challenging surgical cases.

Extracorporeal life support in thoracic emergencies-a narrative review of current evidence

BACKGROUND AND OBJECTIVE

Resuscitative therapies for respiratory and cardiac failure are lifesaving and extended by using extracorporeal life support (ECLS) as mechanical circulatory support (MSC). This review informs the debate to identify the life-threatening thoracic emergencies in which patients may be cannulated for ECLS support.

METHODS

An advanced search was performed in PubMed, Embase, Google Scholar, and references query, assessed in June 2022, identified 761 records. Among them, 74 publications in English were included in the current narrative review.

KEY CONTENT AND FINDINGS

ECLS is an additional tool for organ support in life-threatening thoracic emergencies. It provides bridging to recovery or to decision about destination as definitive therapy, intervention, or surgery. Non-traumatic emergencies include mediastinal mass, acute lung injury (ALI), aspiration, embolisms, acute and chronic heart failure. However, based on the current evidence, trauma, and especially blunt thoracic trauma, is one of the main indications for ECLS use in thoracic emergencies, among others in chest wall fractures, blunt and penetrating lung injuries. ECLS use is always individualized to patient's needs, injury pattern and kind of organ failure, circulatory arrest inclusive, depending on if respiratory or cardiac and circulatory support is needed. Further, ECLS offers the possibility for fast volume resuscitation and rewarming, thus preventing the lethal of trauma: hypothermia, hypoperfusion and acidosis. Anticoagulation may be omitted for some hours or days. Interdisciplinary cooperation between the intensivists, surgeons, anesthesiologists, emergency medical services, an appropriately organized and trained staff, equipment resources and logistical planning are essential for successful outcomes.

CONCLUSIONS

ECLS use in selected life-threatening thoracic emergencies is increasing. The summarized findings appeal to policymakers, and we hope that our summary of recommendations may impact clinical practice and research.

COVID-19 Is an Independent Risk Factor for Detrimental Invasive Fungal Disease in Patients on Veno-Venous Extracorporeal Membrane Oxygenation: A Retrospective Study

Invasive fungal disease (IFD) is associated with the mortality of patients on extracorporeal membrane oxygenation (ECMO). Several risk factors for IFD have been identified in patients with or without ECMO. Here, we assessed the relevance of coronavirus disease (COVID-19) for the occurrence of IFD in patients on veno-venous (V-V) ECMO for respiratory failure. In a retrospective analysis of all ECMO cases between January 2013 and December 2022 (2020-2022 for COVID-19 patients), active COVID-19 and the type, timing and duration of IFD were investigated. Demographics, hospital, ICU length of stay (LoS), duration of ECMO, days on invasive mechanical ventilation, prognostic scores (Respiratory ECMO Survival Prediction (RESP) score, Charlson Comorbidity Index (CCI), Therapeutic Intervention Scoring System (TISS)-10, Sequential Organ Failure Assessment (SOFA) score and Simplified Acute Physiology Score (SAPS)-II) and length of survival were assessed. The association of COVID-19 with IFD was investigated using propensity score matching and uni- and multivariable logistic regression analyses. We identified 814 patients supported with ECMO, and 452 patients were included in further analyses. The incidence of IFD was 4.8% and 11.0% in patients without and with COVID-19, respectively. COVID-19 status represented an independent risk factor for IFD (OR 4.30; CI 1.72-10.85; p: 0.002; multivariable regression analysis). In patients with COVID-19, 84.6% of IFD was candidemia and 15.4% represented invasive aspergillosis (IA). All of these patients died. In patients on V-V ECMO, we report that COVID-19 is an independent risk factor for IFD, which is associated with a detrimental prognosis. Further studies are needed to investigate strategies of antifungal therapy or prophylaxis in these patients.

Expanded extracorporeal membrane oxygenation bridge to heart and lung transplant candidate selection does not impact outcomes compared to traditional candidate selection criteria

Extracorporeal membrane oxygenation is used as a bridge to transplant (ECMO-BTT) in selected patients. The objective of this study was to determine whether 1-year post-transplant and post-ECMO survival are impacted by traditional compared to expanded selection criteria. We performed a retrospective study of patients >17 years who received ECMO as bridge to transplant (BTT) or bridge to transplant decision for lung or combined heart and lung transplantation at the Mayo Clinic Florida and Rochester. Institutional protocol excludes patients >55 years, maintained on steroids, unable to participate in physical therapy, with body mass index >30 or <18.5 kg/m², non-pulmonary end-organ dysfunction, or unmanageable infections from ECMO-BTT. For this study, adherence to this protocol was considered traditional whereas exceptions to the protocol were considered expanded selection criteria. A total of 45 patients received ECMO as bridge therapy. Out of those 29 patients (64%) received ECMO as bridge to transplant and 16 patients (36%) as bridge to transplant decision. The traditional criteria cohort consisted of 15 (33%) patients and expanded criteria cohort consisted of 30 (67%) patients. In the traditional cohort, 9 (60%) of 15 patients were successfully transplanted compared to 16 (53%) of 30 patients in the expanded criteria cohort. No difference in being delisted or dying on the waitlist (OR: 0.58, CI: 0.13-2.58), surviving to 1-year post-transplant (OR: 0.53, CI: 0.03-9.71) or 1-year post-ECMO (OR: 0.77, CI: 0.0.23-2.56) was observed between the traditional criteria and expanded criteria cohorts. At our institution, we did not see differences in odds of 1-year post-transplant and post-ECMO survival between those who met traditional criteria compared to those who did not. Multicenter, prospective studies are needed to evaluate the impact of ECMO-BTT selection criteria.

Bilateral lung transplantation for pediatric pulmonary arterial hypertension: perioperative management and one-year follow-up

Background

Bilateral lung transplantation (LuTx) remains the only established treatment for children with end-stage pulmonary arterial hypertension (PAH). Although PAH is the second most common indication for LuTx, little is known about optimal perioperative management and midterm clinical outcomes.

Methods

Prospective observational study on consecutive children with PAH who underwent LuTx with scheduled postoperative VA-ECMO support at Hannover Medical School from December 2013 to June 2020.

Results

Twelve patients with PAH underwent LuTx (mean age 11.9 years; age range 1.9-17.8). Underlying diagnoses included idiopathic (n = 4) or heritable PAH (n = 4), PAH associated with congenital heart disease (n = 2), pulmonary veno-occlusive disease (n = 1), and pulmonary capillary hemangiomatosis (n = 1). The mean waiting time was 58.5 days (range 1-220d). Three patients were bridged to LuTx on VA-ECMO. Intraoperative VA-ECMO/cardiopulmonary bypass was applied and VA-ECMO was continued postoperatively in all patients (mean ECMO-duration 185 h; range 73-363 h; early extubation). The median postoperative ventilation time was 28 h (range 17-145 h). Echocardiographic conventional and strain analysis showed that 12 months after LuTx, all patients had normal biventricular systolic function. All PAH patients are alive 2 years after LuTx (median follow-up 53 months, range 26-104 months).

Conclusion

LuTx in children with end-stage PAH resulted in excellent midterm outcomes (100% survival 2 years post-LuTx). Postoperative VA-ECMO facilitates early extubation with rapid gain of allograft function and sustained biventricular reverse-remodeling and systolic function after RV pressure unloading and LV volume loading.

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.

Catastrophic complications of PVL-MRSA necrotizing pneumonia presenting as respiratory failure and rhabdomyolysis, case report and review of the literature

Panton-Valentine leucocidin toxin-producing methicillin-resistant staphylococcus aureus is an important uncommon cause of community-acquired pneumonia; we describe a case of necrotizing pneumonia presenting as respiratory failure necessitating early initiation of extracorporeal membrane oxygenation, acute kidney injury and rhabdomyolysis, awareness, prompt recognition and appropriate management are crucial due to possible significant pathology.

Indirect Calorimetry in Spontaneously Breathing, Mechanically Ventilated and Extracorporeally Oxygenated Patients: An Engineering Review

Indirect calorimetry (IC) is considered the gold standard for measuring resting energy expenditure (REE). This review presents an overview of the different techniques to assess REE with special regard to the use of IC in critically ill patients on extracorporeal membrane oxygenation (ECMO), as well as to the sensors used in commercially available indirect calorimeters. The theoretical and technical aspects of IC in spontaneously breathing subjects and critically ill patients on mechanical ventilation and/or ECMO are covered and a critical review and comparison of the different techniques and sensors is provided. This review also aims to accurately present the physical quantities and mathematical concepts regarding IC to reduce errors and promote consistency in further research. By studying IC on ECMO from an engineering point of view rather than a medical point of view, new problem definitions come into play to further advance these techniques.

Bronchoscopic Endobronchial Valve Therapy for Persistent Air Leaks in COVID-19 Patients Requiring Veno-Venous Extracorporeal Membrane Oxygenation

COVID-19 acute respiratory distress syndrome (ARDS) can be associated with extensive lung damage, pneumothorax, pneumomediastinum and, in severe cases, persistent air leaks (PALs) via bronchopleural fistulae (BPF). PALs can impede weaning from invasive ventilation or extracorporeal membrane oxygenation (ECMO). We present a series of patients requiring veno-venous ECMO for COVID-19 ARDS who underwent endobronchial valve (EBV) management of PAL. This is a single-centre retrospective observational study. Data were collated from electronic health records. Patients treated with EBV met the following criteria: ECMO for COVID-19 ARDS; the presence of BPF causing PAL; air leak refractory to conventional management preventing ECMO and ventilator weaning. Between March 2020 and March 2022, 10 out of 152 patients requiring ECMO for COVID-19 developed refractory PALs, which were successfully treated with bronchoscopic EBV placement. The mean age was 38.3 years, 60% were male, and half had no prior co-morbidities. The average duration of air leaks prior to EBV deployment was 18 days. EBV placement resulted in the immediate cessation of air leaks in all patients with no peri-procedural complications. Weaning of ECMO, successful ventilator recruitment and removal of pleural drains were subsequently possible. A total of 80% of patients survived to hospital discharge and follow-up. Two patients died from multi-organ failure unrelated to EBV use. This case series presents the feasibility of EBV placement in severe parenchymal lung disease with PAL in patients requiring ECMO for COVID-19 ARDS and its potential to expedite weaning from both ECMO and mechanical ventilation, recovery from respiratory failure and ICU/hospital discharge.

Unusual presentation of alveolar capillary dysplasia with misalignment of the pulmonary veins in a child with respiratory syncytial virus pneumonia: A case report

Alveolar capillary dysplasia with misalignment of the pulmonary veins (ACDMPV) is a rare congenital diffuse lung disorder, with a fatal course during the neonatal period. We describe an 18-month-old boy who presented with respiratory syncytial virus pneumonia and pulmonary hypertensive crisis requiring extracorporeal membrane oxygenation. Exome sequencing revealed a FOXF1 frameshift variant, NM_001451.2:c.995_998delACTC, inherited from his asymptomatic mother. Genetic findings were compatible with histopathology findings from a lung biopsy. Based on the disease course, histopathology, and outcomes of this case, we believe ACDMPV should be considered a possibility in an infant presenting with hypoxemic respiratory failure, resistant pulmonary hypertension, and vasodilator-induced pulmonary edema. Genetic testing can contribute to the diagnostic process.

Use of bivalirudin for anticoagulation in pediatric extracorporeal membrane oxygenation (ECMO)

This study describes the use of bivalirudin in children on extracorporeal membrane oxygenation (ECMO). Pediatric patients receiving bivalirudin were compared to patients receiving heparin as the anticoagulant on ECMO. Data was collected for children under 18 years of age supported by ECMO from January 2016 to December 2019. Data collected included demographics, diagnosis, ECMO indication, type, and duration, indication for bivalirudin use, dose range, activated partial thromboplastin time (aPTT) levels, minor and major bleeding, hemolysis, and mortality. Forty pediatric patients received ECMO; eight received bivalirudin primarily for anticoagulation. The median age was 4 months (IQR 0.5, 92) in the heparin cohort, 0.6 months (IQR 0.0, 80.0) in the primary bivalirudin cohort. The indication for ECMO was respiratory in 5 patients (18%) in the heparin group versus 6 (75%) in the primary bivalirudin group, cardiac in 18 (67%) in heparin versus 1 (12.5%) in primary bivalirudin, and extracorporeal-cardiopulmonary resuscitation (E-CPR) in 4 (15%) in heparin versus 1 (12.5%) in primary bivalirudin. Bivalirudin was the initial anticoagulant for eight patients (66.6%) while three (25%) were switched due to concern for heparin-induced thrombocytopenia (HIT) and one (8%) for heparin resistance. The median time to achieve therapeutic aPTT was 14.5 hours compared to 12 hours in the heparin group. Sixty-five percent of aPTT values in the bivalirudin and 44% of values in the heparin group were in the therapeutic range in the first 7 days. Patients with primary bivalirudin use had significantly lower dose requirement at 12 (p = 0.003), 36 (p = 0.007), and 48 (p = 0.0002) hours compared to patients with secondary use of bivalirudin. One patient (12.5%) had major bleeding, and two patients (25%) required circuit change in the primary bivalirudin cohort. Bivalirudin may provide stable and successful anticoagulation in children. Further large, multicenter studies are needed to confirm these findings.

Impact of in utero drug exposure on neonates requiring ECMO: A retrospective cohort study

The incidence of in utero drug exposure (IUDE) and neonatal extracorporeal membrane oxygenation (ECMO) utilization have both increased over the past decade. However, there are no studies to date that examine the impact that IUDE has on neonates requiring ECMO. In this retrospective cohort study, we compared the clinic course and outcomes of neonates who were placed on ECMO with IUDE vs. neonates without IUDE. Analysis included data extracted from medical records from all neonatal ECMO runs between January 2014 and January 2021 at the University of Kentucky Children's Hospital. A total of 56 neonatal patients were placed on ECMO during this time period and there were a total of 57 ECMO runs. Nearly one-third of neonates (16) had documented IUDE. There were no differences in gestational age, length of ECMO run, survival to discharge, or number of major complications while on ECMO in the neonates with IUDE compared to those without. In contrast, greater use of sedative and analgesic adjuvant medications during ECMO was required for IUDE-ECMO cases (p < 0.01). Trending results indicated that post-ECMO feeding complications and total hospitalization length were also greater in the IUDE-ECMO group. These findings illustrate the complex influence of prenatal drug exposures on neonatal patient care and warrant the development of clinical care strategies optimized for this unique patient group.

The anesthetic management and the role of extracorporeal membrane oxygenation for giant mediastinal tumor surgery

Mediastinal tumors are a remarkably diverse category. They include malignant and benign forms with different rates of disease progression and tissue invasion. Anesthesiologists may encounter significant difficulties in managing patients with giant mediastinal tumors due to the non-negligible occurrence of severe cardiorespiratory collapse. Respiratory complications ensue from the compression of the airways induced by the mediastinal mass: the compressive effects may be exacerbated by positioning or anesthesia induction. Furthermore, the compression or invasion of major vessels may elicit acute cardiovascular collapse. The specter of sudden cardiorespiratory deterioration should lead the anesthesiologist to careful planning: acknowledging clinical and radiological signs that may presage an increased risk of life-threatening complications is of pivotal importance. This review aims to present a strategy for treating patients with mediastinal masses, starting with the pathophysiological elements and moving through preoperative care, intraoperative behavior, and the recovery period. We will also focus on respiratory and cardiovascular issues, emphasizing the need for extracorporeal membrane oxygenation (ECMO) as a rescue and crucial component of the anesthesia strategy. Understanding the physiological alterations after anesthesia induction can aid in identifying and treating potential problems. In addition, we attempted to offer insight into multimodal anesthesia and analgesia management: we emphasize the importance of a thorough preoperative assessment and the need for reviewing extracorporeal support not just a resuscitative strategy but as an integrated component of the perioperative care.

The economic burden and long-term mortality in survivors of extracorporeal membrane oxygenation in South Korea

Background

The economic burden for extracorporeal membrane oxygenation (ECMO) survivors is a critical issue. We investigated the total healthcare costs for one year following ECMO support and its association with three-year all-cause mortality.

Methods

This population-based cohort study used data from the National Health Insurance Service (NHIS) in South Korea. Adult ECMO survivors (age ≥18 years who were alive ≥365 days following ECMO support) from January 1, 2005, to December 31, 2018, were included. The total healthcare costs for one year included all the expenses for hospital and outpatient clinic visits after discharge.

Results

In total, 6,044 patients were included in the final analysis comprising 3,566 (59.0%) in the cardiac indication group, 658 (10.9%) in the respiratory indication group, and 1,820 (30.1%) in the "other" group. The median total healthcare cost was United States Dollars (USD) 46,308.0 [interquartile range (IQR): 25,727.0-86,924.8]. The median ECMO support and hospital stay durations were three (IQR: 1-7) days and 25 (IQR: 15-31) days. In the multivariable Cox regression model, a USD 1,000 increase in the total healthcare cost was associated with an increase in the three-year all-cause mortality (hazard ratio, 1.01; 95% CI: 1.00-1.01; P=0.015).

Conclusions

After one year, ECMO survivors accrued USD 46,308 in healthcare costs in South Korea. An increase in the total healthcare cost was associated with a higher risk of three-year all-cause mortality among ECMO survivors.

Failing Fontan cardiovascular support: Review

BACKGROUND

Although all congenital heart defects (CHD) present unique challenges, univentricular CHD are especially challenging given the difficulty of passively perfusing pulmonary blood flow. Three surgical procedures are required within the first years of life, with the final completing a Fontan circulation in which the inferior vena cava is connected to the pulmonary artery and previously connected superior vena cava. This allows passive venous return to the pulmonary circulation then flow into the single ventricle for systemic circulation.

METHODS

Although a Fontan provides successful palliation for two to three decades, many complications can arise as pulmonary resistance must remain low to allow adequate forward flow. Eventually, the failing Fontan circulation requires temporary support as the patient awaits a heart transplant. We reviewed PubMed, Google Scholar, and U. Kentucky library for different techniques evaluated to support a failing Fontan circulation.

RESULTS

Multiple technologies have been developed as a bridge to transplant to decrease morbidity. Innovative types of extracorporeal membrane oxygenation, ventricular assist devices, and total artificial hearts have been attempted in laboratory settings as well as in Fontan patients with varying degrees of success. This article emphasizes the strengths and weaknesses of each technology in the context of Fontan physiology.

CONCLUSION

The end game for these patients remains a heart transplant. Without easy access to donors, each of the options discussed is a potential bridge to limit morbidity and mortality until a suitable donor heart becomes available.

Mechanical circulatory support in ventricular arrhythmias

In atrial and ventricular tachyarrhythmias, reduced time for ventricular filling and loss of atrial contribution lead to a significant reduction in cardiac output, resulting in cardiogenic shock. This may also occur during catheter ablation in 11% of overall procedures and is associated with increased mortality. Managing cardiogenic shock and (supra) ventricular arrhythmias is particularly challenging. Inotropic support may exacerbate tachyarrhythmias or accelerate heart rate; antiarrhythmic drugs often come with negative inotropic effects, and electrical reconversions may risk worsening circulatory failure or even cardiac arrest. The drop in native cardiac output during an arrhythmic storm can be partly covered by the insertion of percutaneous mechanical circulatory support (MCS) devices guaranteeing end-organ perfusion. This provides physicians a time window of stability to investigate the underlying cause of arrhythmia and allow proper therapeutic interventions (e.g., percutaneous coronary intervention and catheter ablation). Temporary MCS can be used in the case of overt hemodynamic decompensation or as a “preemptive strategy” to avoid circulatory instability during interventional cardiology procedures in high-risk patients. Despite the increasing use of MCS in cardiogenic shock and during catheter ablation procedures, the recommendation level is still low, considering the lack of large observational studies and randomized clinical trials. Therefore, the evidence on the timing and the kinds of MCS devices has also scarcely been investigated. In the current review, we discuss the available evidence in the literature and gaps in knowledge on the use of MCS devices in the setting of ventricular arrhythmias and arrhythmic storms, including a specific focus on pathophysiology and related therapies.

Biomarkers for differentiation of coronavirus disease 2019 or extracorporeal membrane oxygenation related inflammation and bacterial/fungal infections in critically ill patients: A prospective observational study

Secondary infections in coronavirus disease 2019 (COVID-19) patients are difficult to distinguish from inflammation associated with COVID-19 and/or extracorporeal membrane oxygenation (ECMO). Therefore, highly specific and sensitive biomarkers are needed to identify patients in whom antimicrobial therapy can be safely withheld. In this prospective monocentric study, 66 COVID-19 patients admitted to the intensive care unit (ICU) for ECMO evaluation were included. A total of 46 (70%) patients with secondary infections were identified by using broad microbiological and virological panels and standardized diagnostic criteria. Various laboratory parameters including C-reactive protein (CRP), interleukin (IL)-6, procalcitonin (PCT), and IL-10 were determined at time of study inclusion. The best test performance for differentiating bacterial/fungal secondary infections and COVID-19 and/or ECMO associated inflammation was achieved by IL-10 (ROC-AUC 0.84) and a multivariant step-wise regression model including CRP, IL-6, PCT, and IL-10 (ROC-AUC 0.93). Data obtained in the present study highlights the use of IL-10 to differentiate secondary bacterial/fungal infections from COVID-19 and/or ECMO associated inflammation in severely ill COVID-19 patients.

Coronavirus Infection COVID-19 and Pregnancy

The novel coronavirus infection SARS-CoV-2, which broke out in China in December 2019, has rapidly spread around the world. On March 11, 2020, the World Health Organization (WHO) assigned this infection pandemic status. Pregnant women and puerperae occupy a special place in the structure of the incidence of COVID-19. For more than a year and a half, the Lapino Clinical Hospital of the Mother and Child Group of Companies has accumulated significant experience in managing patients with COVID-19, including pregnant women and puerperae. This article presents the features of the course of the new coronavirus infection in pregnant women and puerperae during various periods of the pandemic, the experience of managing pregnancy and childbirth in the above group of patients, and methods of treatment.

Veno-Arterial Extracorporeal Membrane Oxygenation (ECMO) Impairs Bradykinin-Induced Relaxation in Neonatal Porcine Coronary Arteries

Extracorporeal membrane oxygenation (ECMO) is a lifesaving support for respiratory and cardiovascular failure. However, ECMO induces a systemic inflammatory response syndrome that can lead to various complications, including endothelial dysfunction in the cerebral circulation. We aimed to investigate whether ECMO-associated endothelial dysfunction also affected coronary circulation. Ten-day-old piglets were randomized to undergo either 8 h of veno-arterial ECMO (n = 5) or no treatment (Control, n = 5). Hearts were harvested and coronary arteries were dissected and mounted as 3 mm rings in organ baths for isometric force measurement. Following precontraction with the thromboxane prostanoid (TP) receptor agonist U46619, concentration−response curves to the endothelium-dependent vasodilator bradykinin (BK) and the nitric oxide (NO) donor (endothelium-independent vasodilator) sodium nitroprusside (SNP) were performed. Relaxation to BK was studied in the absence or presence of the NO synthase inhibitor Nω-nitro-L-arginine methyl ester HCl (L-NAME). U46619-induced contraction and SNP-induced relaxation were similar in control and ECMO coronary arteries. However, BK-induced relaxation was significantly impaired in the ECMO group (30.4 ± 2.2% vs. 59.2 ± 2.1%; p < 0.0001). When L-NAME was present, no differences in BK-mediated relaxation were observed between the control and ECMO groups. Taken together, our data suggest that ECMO exposure impairs endothelium-derived NO-mediated coronary relaxation. However, there is a NO-independent component in BK-induced relaxation that remains unaffected by ECMO. In addition, the smooth muscle cell response to exogenous NO is not altered by ECMO exposure.

Intracerebral Hemorrhage associated COVID-19 patient with normal coagulation profile after ECMO treatment: A case report"

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a novel coronavirus-caused infectious acute respiratory disease that can progress to severe acute respiratory distress syndrome (ARDS). For severe cases, extracorporeal membrane oxygenation (ECMO) is an excellent treatment option. ECMO had a number of side effects, including bleeding. Intracerebral hemorrhage can occur in COVID patients due to a variety of mechanisms, including covid's effect on ACE-2 receptors and subsequent hypertension, coagulopathy, DIC, or medication, such as anticoagulant use.

CASE

We present a case of a 53-year-old male COVID-19 patient who developed multiple, massive, severe intracerebral hemorrhages (ICH) despite a normal coagulation profile after ECMO treatment.

CONCLUSION

COVID-19 can progress to severe acute respiratory distress syndrome (ARDS), necessitating the use of extracorporeal membrane oxygenation (ECMO). Although ICH is not a common complication in patients with COVID-19 disease, it is unknown why this patient had a lower threshold of ICH despite having a normal coagulation profile.