Complications Associated With Venovenous Extracorporeal Membrane Oxygenation-What Can Go Wrong?

Vascular Complications in Extracorporeal Membrane Oxygenation-A Narrative Review

The establishment of a peripheral ECMO circuit can lead to significant arterial and venous complications in 10-30% of patients. Vascular complications, particularly acute limb ischemia, are associated with worsening overall outcomes. Limb ischemia occurs significantly more frequently in the early stages of VA ECMO than in VV ECMO. Mechanisms of limb ischemia include arterial obstruction, cannulation injury, loss of pulsatile flow, thromboembolism, venous stasis from compressive obstruction with large venous cannulas, and systemic vasoconstriction due to shock and pharmacologic vasoconstriction. The care team may use several mitigation strategies to prevent limb ischemia. Arterial and venous complications can be mitigated by careful access site selection, minimizing cannula size, placement of distal perfusion and/or outflow catheter(s), and continuous NIRS monitoring. Rapid intervention, when ischemia or compartment syndrome occurs, can reduce limb loss but may not affect the mortality and morbidity of the ECMO patient in the long term due to their underlying conditions and the etiology of the ECMO need.

Device associated complications in the intensive care unit

Invasive devices are routinely used in the care of critically ill patients. Although they are often essential components of patient care, devices such as intravascular catheters, endotracheal tubes, and ventilators are a common source of complications in the intensive care unit. Critical care practitioners who use these devices need to use strategies for risk reduction and understand approaches to management when adverse events occur. This review discusses the identification, prevention, and management of complications of vascular, airway, and mechanical support devices commonly used in the intensive care unit.

Outcome of COVID-19 patients treated with VV-ECMO in Tyrol during the pandemic

INTRODUCTION

A small percentage of patients infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV‑2) showed severe respiratory deterioration requiring treatment with extracorporeal membrane oxygenation (ECMO). During the pandemic surges availability of ECMO devices was limited and resources had to be used wisely. The aim of this analysis was to determine the incidence and outcome of venovenous (VV) ECMO patients in Tyrol, when criteria based on the Extracorporeal Life Support Organization (ELSO) guidelines for VV-ECMO initiation were established.

METHODS

This is a secondary analysis of the Tyrol-CoV-ICU-Reg, which includes all patients admitted to an intensive care unit (ICU) during the coronavirus disease 2019 (COVID-19) pandemic in Tyrol. Of the 13 participating departments, VV-ECMO was performed at 4 units at the University Hospital Innsbruck.

RESULTS

Overall, 37 (3.4%) of 1101 patients were treated with VV-ECMO during their ICU stay. The hospital mortality rate was approximately 40% (n = 15). Multiorgan failure due to sepsis was the most common cause of death. No significant difference in survival rates between newly initiated and experienced centers was observed. The median survival time of nonsurvivors was 27 days (interquartile range, IQR: 22-36 days) after initiation of VV-ECMO. Acute kidney injury meeting the Kidney Disease: Improving Global Outcomes (KDIGO) criteria occurred in 48.6%. Renal replacement therapy (RRT) was initiated in 12 (32.4%) patients after a median of 18 days (IQR: 1-26 days) after VV-ECMO start. The median length of ICU and hospital stays were 38 days (IQR: 30-55 days) and 50 days (IQR: 37-83 days), respectively.

DISCUSSION

Despite a rapidly increased demand and the resulting requirement to initiate an additional ECMO center, we could demonstrate that a structured approach with interdisciplinary collaboration resulted in favorable survival rates similar to multinational reports.

Impact of Extracorporeal Membrane Oxygenation Bridging Duration on Lung Transplant Outcomes

BACKGROUND

We sought to characterize the association between venovenous extracorporeal membrane oxygenation (VV-ECMO) bridging duration and outcomes in patients listed for lung transplantation.

METHODS

A retrospective observational study was conducted using the Organ Procurement and Transplantation Network (OPTN) database to identify adults (aged ≥18 years) who were listed for lung transplantation between 2016 and 2020 and were bridged with VV-ECMO. Patients were then stratified into groups, determined by risk inflection points, depending on the amount of time spent on pretransplant ECMO: group 1 (≤5 days), group 2 (6-10 days), group 3 (11-20 days), and group 4 (>20 days). Waiting list survival between groups was analyzed using Fine-Gray competing risk models. Posttransplant survival was compared using Cox regression.

RESULTS

Of 566 eligible VV-ECMO bridge-to-lung-transplant patients (median age, 54 years, 49% men), 174 (31%), 124 (22%), 130 (23%), and 138 (24%) were categorized as groups 1, 2, 3, and 4, respectively. Overall, median duration of VV-ECMO was 10 days (interquartile range, 1-211 days), and 178 patients (31%) died on the waiting list. In the Fine-Gray model, compared with group 1, patients bridged with longer ECMO durations in group 2 (subdistribution hazard ratio [SHR], 2.95; 95% CI, 1.63-5.35), group 3 (SHR, 3.96; 95% CI, 2.36-6.63), and group 4 (SHR, 4.33; 95% CI, 2.59-7.22, all P < .001) were more likely to die on the waiting list. Of 388 patients receiving a transplant, pretransplant ECMO duration was not associated with 1-year survival in Cox regression.

CONCLUSIONS

Prolonged duration of ECMO bridging was associated with worse waiting list mortality but did not impact survival after lung transplant. Prioritization of very early transplantation may improve waiting list outcomes in this population.

Isolated Lung Ventilation With Tracheostomy Using Two Intubation Tubes for Severe Endotracheal Hemorrhage Due to Pulmonary Contusion

A 72-year-old man presented with severe pulmonary contusions and multiple traumas, including aortic injury, pelvic fracture, and renal injury. The patient required multidisciplinary treatment, including transcatheter arterial embolization, thoracic endovascular aortic repair, right lung upper lobe partial resection, and massive transfusion. During the initial treatment, the patient experienced respiratory failure due to endotracheal bleeding, and we attempted isolated lung ventilation with a 37 Fr double-lumen endotracheal intubation tube. Although drainage by suction and protection of the healthy lung was vital, the patient was unable to maintain ventilation volume because of poor drainage. Additionally, the respiratory status deteriorated. To resolve the situation, a tracheotomy was performed and two endotracheal intubation tubes (6.0 mm inner diameter, and 9.0 mm outer diameter) were inserted through a large U-shaped tracheal hole 18 hours after admission. The respiratory status of the patient gradually improved after the procedure. There were two advantages of this method of respiratory management. Firstly, each of the two endotracheal tubes had a separate cuff, allowing more reliable separation of the healthy lung from the injured lung. Secondly, bronchoscopes of sufficient diameter (4.9 mm outer diameter ) were used bilaterally, allowing sufficient drainage of viscous airway secretions mixed with hematoma and improving atelectasis. Although venovenous extracorporeal membrane oxygenation is a crucial support tool when the respiratory status deteriorates due to severe pulmonary contusions, our method of airway management may be attempted in patients with multiple traumatic injuries with coagulopathy.

"Decompression illness" on extracorporeal membrane oxygenation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is increasingly being used for critically ill patients with cardiopulmonary failure. Air in the ECMO circuit is an emergency, a rare but fatal complication.

CASE PRESENTATION

We introduce a case of a 76-year-old female who suffered from cardiac arrest complicated with severe trauma and was administered veno-arterial extracorporeal membrane oxygenation. In managing the patient with ECMO, air entered the ECMO circuit, which had not come out nor was folded or broken. Although the ECMO flow was quickly re-established, the patient died 6 h after initiating ECMO therapy.

CONCLUSIONS

In this case report, the reason for the complication is drainage insufficiency. This phenomenon is similar to decompression sickness. Understanding this complication is very helpful for educating the ECMO team for preventing this rare but devastating complication of fatal decompression sickness in patients on ECMO.

Differential Hypoxia Risk in Cardiopulmonary Arrest Patients Undergoing Veno-Arterial Extracorporeal Membrane Oxygenation and IMPELLA Support

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a therapeutic strategy for managing cardiogenic shock. However, it carries the risk of cardiogenic pulmonary edema, potentially leading to differential hypoxia. Although IMPELLA can mitigate pulmonary congestion, the combination of VA-ECMO and IMPELLA has frequently resulted in differential hypoxia, requiring a transition from VA-ECMO to veno-arteriovenous extracorporeal membrane oxygenation (VAV-ECMO). Therefore, this study aimed to examine the influence of IMPELLA on the incidence of differential hypoxia, necessitating a shift to VAV-ECMO. This single-center, retrospective, observational study included patients who experienced cardiopulmonary arrest and received treatment with VA-ECMO combined with an intra-aortic balloon pump (IABP) or IMPELLA between 2017 and 2022. The primary endpoint assessed the incidence of differential hypoxia, necessitating a switch to VAV-ECMO. Patients with cardiopulmonary arrest received treatment with VA-ECMO in combination with IABP (N = 28) or IMPELLA (N = 29). There was a significant increase in differential hypoxia 96 hours post-VA-ECMO initiation in the IMPELLA group, necessitating a transition to VAV-ECMO. The combination of VA-ECMO and IMPELLA in patients experiencing cardiopulmonary arrest may significantly increase the risk of differential hypoxia. A multidisciplinary approach employing mechanical circulatory support is crucial, with ongoing consideration of the potential risks associated with differential hypoxia.

Web-based Dashboard on ECMO Utilization in Germany: An Interactive Visualization, Analyses, and Prediction Based on Real-life Data

In Germany, a comprehensive reimbursement policy for extracorporeal membrane oxygenation (ECMO) results in the highest per capita use worldwide, although benefits remain controversial. Public ECMO data is unstructured and poorly accessible to healthcare professionals, researchers, and policymakers. In addition, there are no uniform policies for ECMO allocation which confronts medical personnel with ethical considerations during health crises such as respiratory virus outbreaks.Retrospective information on adult and pediatric ECMO support performed in German hospitals was extracted from publicly available reimbursement data and hospital quality reports and processed to create the web-based ECMO Dashboard built on Open-Source software. Patient-level and hospital-level data were merged resulting in a solid base for ECMO use analysis and ECMO demand forecasting with high spatial granularity at the level of 413 county and city districts in Germany.The ECMO Dashboard ( https://www.ecmo-dash.de/ ), an innovative visual platform, presents the retrospective utilization patterns of ECMO support in Germany. It features interactive maps, comprehensive charts, and tables, providing insights at the hospital, district, and national levels. This tool also highlights the high prevalence of ECMO support in Germany and emphasizes districts with ECMO surplus - where patients from other regions are treated, or deficit - origins from which ECMO patients are transferred to other regions. The dashboard will evolve iteratively to provide stakeholders with vital information for informed and transparent resource allocation and decision-making.Accessible public routine data could support evidence-informed, forward-looking resource management policies, which are urgently needed to increase the quality and prepare the critical care infrastructure for future pandemics.

Extracorporeal Membrane Oxygenation as a Bridge Therapy Prior to Surgery in a Patient With Echinococcus Cyst Rupture: A Case Report and Literature Review

Tapeworms of the genus Echinococcus cause parasitic disease in humans through the ingestion of eggs in contaminated food and water. Rupture of slowly enlarging cysts in the liver, lungs, and other organs can be life-threatening and many deaths are recorded yearly worldwide. Surgery and removal of such cysts remain the most effective treatment. Veno-venous extracorporeal membrane oxygenation (ECMO) routinely placed in the ICU in patients with acute respiratory distress syndrome (ARDS), may provide time and adequate oxygenation for the completion of surgery in echinococcosis cases. In this article, we present a rare case of pulmonary echinococcosis in a young patient requiring ECMO support prior to surgery.

Head-to-toe bedside ultrasound for adult patients on extracorporeal membrane oxygenation

Bedside ultrasound represents a well-suited diagnostic and monitoring tool for patients on extracorporeal membrane oxygenation (ECMO) who may be too unstable for transport to other hospital areas for diagnostic tests. The role of ultrasound, however, starts even before ECMO initiation. Every patient considered for ECMO should have a thorough ultrasonographic assessment of cardiac and valvular function, as well as vascular anatomy without delaying ECMO cannulation. The role of pre-ECMO ultrasound is to confirm the indication for ECMO, identify clinical situations for which ECMO is not indicated, rule out contraindications, and inform the choice of ECMO configuration. During ECMO cannulation, the use of vascular and cardiac ultrasound reduces the risk of complications and ensures adequate cannula positioning. Ultrasound remains key for monitoring during ECMO support and troubleshooting ECMO complications. For instance, ultrasound is helpful in the assessment of drainage insufficiency, hemodynamic instability, biventricular function, persistent hypoxemia, and recirculation on venovenous (VV) ECMO. Lung ultrasound can be used to monitor signs of recovery on VV ECMO. Brain ultrasound provides valuable diagnostic and prognostic information on ECMO. Echocardiography is essential in the assessment of readiness for liberation from venoarterial (VA) ECMO. Lastly, post decannulation ultrasound mainly aims at identifying post decannulation thrombosis and vascular complications. This review will cover the role of head-to-toe ultrasound for the management of adult ECMO patients from decision to initiate ECMO to the post decannulation phase.

Age and associated outcomes among patients receiving venovenous extracorporeal membrane oxygenation for acute respiratory failure: analysis of the Extracorporeal Life Support Organization registry

PURPOSE

Venovenous extracorporeal membrane oxygenation (VV-ECMO) can be used to support patients with refractory acute respiratory failure, though guidance on patient selection is lacking. While age is commonly utilized as a factor in establishing the potential VV-ECMO candidacy of these patients, little is known regarding its association with outcome. We studied the association between increasing patient age and outcomes among patients with acute respiratory failure receiving VV-ECMO.

METHODS

In this registry-based cohort study, we used individual patient data from 144 centres. We included adult patients (≥ 18 years of age) receiving VV-ECMO from 2017 to 2022. The primary outcome was hospital mortality. Secondary outcomes included a composite of complications following initiation of VV-ECMO. We conducted Bayesian analyses to estimate the association between chronological age and outcomes.

RESULTS

We included 27,811 patients receiving VV-ECMO. Of these, 11,533 (41.5%) died in hospital. For the analysis conducted using weakly informed priors, and as compared to the reference category of age 18-29, the age brackets of 30-39 (odds ratio [OR] 1.17, 95% credible interval [CrI] 1.06-1.31), 40-49 (OR 1.65, 95% CrI 1.49-1.82), 50-59 (OR 2.39, 95% CrI 2.16-2.61), 60-69 (OR 3.29, 95% CrI 2.97-3.67), 70-79 (OR 4.57, 95% CrI 3.90-5.37), and ≥ 80 (OR 8.08, 95% CrI 4.85-13.74) were independently associated with increasing hospital mortality. Similar results were found between increasing age and post-ECMO complications.

CONCLUSIONS

Among patients receiving VV-ECMO for acute respiratory failure, increasing age is significantly associated with poorer outcomes, and this association emerges as early as 30 years of age.

Deoxyribonuclease I Alleviates Septic Liver Injury in a Rat Model Supported by Venoarterial Extracorporeal Membrane Oxygenation

Sepsis is an unusual systemic reaction with high mortality and secondary septic liver injury is proposed to be the major cause of mortality. Extracorporeal membrane oxygenation (ECMO) can enhance terminal organ perfusion by elevating circulatory support which is used in severe sepsis patients. However, the interaction of blood components with the biomaterials of the extracorporeal membrane elicits a systemic inflammatory response. Besides, inflammation and apoptosis are the main mediators in the pathophysiology of septic liver injury. Therefore, we investigated the protective effect of Deoxyribonuclease I (DNase I) against septic liver injury supported by ECMO in rats. Sepsis was induced by lipopolysaccharide (LPS) and 24 hours after the administration, the rats were treated with ECMO. Then blood samples and liver tissues were collected. DNase I significantly attenuated the level of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and significantly decreased hepatic levels of NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome, myeloperoxidase (MPO), downstream inflammatory factor interleukin-1β (IL-1β) and interleukin-18 (IL-18), and improved neutrophil infiltration. Additionally, DNase I significantly reduced the expression of apoptosis key protein and terminal-deoxynucleotidyl transferase-mediated nick end labeling (TUNEL)-labeled apoptotic hepatocytes. In summary, our findings demonstrated that DNase I alleviates liver injury in ECMO-supported septic rats by reducing the inflammatory and apoptotic responses.

The Roles of Venopulmonary Arterial Extracorporeal Membrane Oxygenation

OBJECTIVES

Concise definitive review of the use of venopulmonary arterial extracorporeal membrane oxygenation (V-PA ECMO) support in patients with cardiopulmonary failure.

DATA SOURCES

Original investigations identified through a PubMed search with search terms "percutaneous right ventricular assist device," "oxy-RVAD," "V-PA ECMO," and "veno-pulmonary arterial ECMO" were reviewed and evaluated for relevance.

STUDY SELECTION

Studies that included more than three patients supported with V-PA ECMO were included.

DATA EXTRACTION

Clinically relevant data from included studies, including patient-important outcomes, were summarized and discussed.

DATA SYNTHESIS

We identified four groups of patients where V-PA ECMO has been studied: acute respiratory distress syndrome, right ventricular dysfunction after left ventricular assist device placement, bridge to lung transplantation, and pulmonary embolism. Most identified works are small, single center, and retrospective in nature, precluding definitive conclusions regarding the efficacy of V-PA ECMO. There have been no clinical trials evaluating the efficacy of V-PA ECMO for any indication.

CONCLUSIONS

V-PA ECMO is a promising form of extracorporeal support for patients with right ventricular dysfunction. Future work should focus on identifying the optimal timing and populations for the use of V-PA ECMO.

Extracorporeal membrane oxygenation in adult patients with sepsis and septic shock: Why, how, when, and for whom

Sepsis and septic shock remain the leading causes of death in intensive care units. Some patients with sepsis fail to respond to routine treatment and rapidly progress to refractory respiratory and circulatory failure, necessitating extracorporeal membrane oxygenation (ECMO). However, the role of ECMO in adult patients with sepsis has not been fully established. According to existing studies, ECMO may be a viable salvage therapy in carefully selected adult patients with sepsis. The choice of venovenous, venoarterial, or hybrid ECMO modes is primarily determined by the patient's oxygenation and hemodynamics (distributive shock with preserved cardiac output, septic cardiomyopathy (left, right, or biventricular heart failure), or right ventricular failure caused by acute respiratory distress syndrome). Veno-venous ECMO can be used in patients with sepsis and severe acute respiratory distress syndrome when conventional mechanical ventilation fails, and early application of veno-arterial ECMO in patients with sepsis-induced refractory cardiogenic shock may be critical in improving their chances of survival. When ECMO is indicated, the choice of an appropriate mode and determination of the optimal timing of initiation and weaning are critical, particularly in an experienced ECMO center. Furthermore, some special issues, such as ECMO flow, anticoagulation, and antibiotic therapy, should be noted during the management of ECMO support.

Assessing Venous Thrombotic Risks in Extracorporeal Membrane Oxygenation-Supported Patients: A Systematic Review and Meta-Analysis

This study investigates the prevalence and risk factors associated with venous thrombotic events in patients receiving (ECMO) support. Systematic review and meta-analysis of case-control and cohort studies. PubMed, Cochrane Library, Embase, CINAHL, Web of Science, Scopus, and ProQuest databases from inception through November 25, 2023.Case-control and cohort studies focusing on the prevalence and risk factors for venous thrombotic events in patients supported by ECMO. Identification of risk factors and calculation of incidence rates. Nineteen studies encompassing 10,767 participants were identified and included in the analysis. The pooled prevalence of venous thrombotic events among patients receiving ECMO support was 48% [95% confidence interval (CI) 0.37-0.60, I2 = 97.18%]. Factors associated with increased incidence rates included longer duration of ECMO support (odds ratio [OR] 1.08, 95% CI 1.07-1.09, I2 = 49%), abnormal anti-coagulation monitoring indicators (OR 1.02, 95% CI 1.00-1.04, I2 = 84%), and type of ECMO cannulation (OR 1.77, 95% CI 1.14-3.34, I2 = 64%). The pooled prevalence of venous thrombotic events in patients with ECMO support is high. Increased risk is associated with extended duration of ECMO support, abnormal anti-coagulation monitoring, and specific types of ECMO cannulation.

Ventilatory Management of Patients with Acute Respiratory Distress Syndrome Due to SARS-CoV-2

The emergence of the new SARS-CoV-2 in December 2019 caused a worldwide pandemic of the resultant disease, COVID-19. There was a massive surge in admissions to intensive care units (ICU), notably of patients with hypoxaemic acute respiratory failure. In these patients, optimal oxygen therapy was crucial. In this article, we discuss tracheal intubation to provide mechanical ventilation in patients with hypoxaemic acute respiratory failure due to SARS-CoV-2. We first describe the pathophysiology of respiratory anomalies leading to acute respiratory distress syndrome (ARDS) due to infection with SARS-CoV-2, and then briefly review management, focusing particularly on the ventilation strategy. Overall, the ventilatory management of ARDS due to SARS-CoV-2 infection is largely the same as that applied in ARDS from other causes, and lung-protective ventilation is recommended. The difference lies in the initial clinical presentation, with profound hypoxaemia often observed concomitantly with near-normal pulmonary compliance.

Early Blood Clot Detection Using Forward Scattering Light Measurements Is Not Superior to Delta Pressure Measurements

The occurrence of thrombus formation within an extracorporeal membrane oxygenator is a common complication during extracorporeal membrane oxygenation therapy and can rapidly result in a life-threatening situation due to arterial thromboembolism, causing stroke, pulmonary embolism, and limb ischemia in the patient. The standard clinical practice is to monitor the pressure at the inlet and outlet of oxygenators, indicating fulminant, obstructive clot formation indicated by an increasing pressure difference (ΔP). However, smaller blood clots at early stages are not detectable. Therefore, there is an unmet need for sensors that can detect blood clots at an early stage to minimize the associated thromboembolic risks for patients. This study aimed to evaluate if forward scattered light (FSL) measurements can be used for early blood clot detection and if it is superior to the current clinical gold standard (pressure measurements). A miniaturized in vitro test circuit, including a custom-made test chamber, was used. Heparinized human whole blood was circulated through the test circuit until clot formation occurred. Four LEDs and four photodiodes were placed along the sidewall of the test chamber in different positions for FSL measurements. The pressure monitor was connected to the inlet and the outlet to detect changes in ΔP across the test chamber. Despite several modifications in the LED positions on the test chamber, the FSL measurements could not reliably detect a blood clot within the in vitro test circuit, although the pressure measurements used as the current clinical gold standard detected fulminant clot formation in 11 independent experiments.

Standardized approach for extubation during extracorporeal membrane oxygenation in severe acute respiratory distress syndrome: a prospective observational study

BACKGROUND

Extubation during extracorporeal oxygenation (ECMO) in severe acute respiratory distress syndrome (ARDS) has not been well studied. Despite the potential benefits of this strategy, weaning from ECMO before liberation from invasive mechanical ventilation remains the most frequent approach. Our aim was to evaluate the safety and feasibility of a standardized approach for extubation during ECMO in patients with severe ARDS.

RESULTS

We conducted a prospective observational study to assess the safety and feasibility of a standardized approach for extubation during ECMO in severe ARDS among 254 adult patients across 4 intensive care units (ICU) from 2 tertiary ECMO centers over 6 years. This consisted of a daily assessment of clinical and gas exchange criteria based on an Extracorporeal Life Support Organization guideline, with extubation during ECMO after validation by a dedicated intensive care medicine specialist. Fifty-four (21%) patients were extubated during ECMO, 167 (66%) did not reach the clinical criteria, and in 33 (13%) patients, gas exchange precluded extubation during ECMO. At ECMO initiation, there were fewer extrapulmonary organ dysfunctions (lower SOFA score [OR, 0.88; 95% CI, 0.79-0.98; P = .02] with similar PaO2/FiO2) when compared with patients not extubated during ECMO. Extubation during ECMO associated with shorter duration of invasive mechanical ventilation (7 (4-18) vs. 32 (18-54) days; P < .01) and of ECMO (12 (7-25) vs. 19 (10-41) days; P = .01). This was accompanied by a lower incidence of hemorrhagic shock (2 vs. 11%; P = .05), but more cannula-associated deep vein thrombosis (49 vs. 31%; P = .02) and failed extubation (20 vs. 6%; P < .01). There were no increased major adverse events. Extubation during ECMO is associated with a lower risk of all-cause death, independently of measured confounding (adjusted logistic regression OR 0.23; 95% confidence interval 0.08-0.69, P = .008).

CONCLUSIONS

A standardized approach was safe and feasible allowing extubation during ECMO in 21% of patients with severe ARDS, selecting patients who will have a shorter duration of invasive mechanical ventilation, ECMO course, and ICU stay, as well as fewer infectious complications, and high hospital survival.

VV-ECMO as bridge and safety net for successful therapeutic polypragmasy in a case of influenza-triggered near-fatal asthma

Key Clinical Message

In near-fatal asthma, the combination of ECMO therapy and isoflurane application via an intensive care ventilator with an anesthetic conservation device represents a therapeutic combination in seemingly hopeless clinical situations.

Abstract

We report a case of an adult patient with near-fatal asthma, who was implanted venovenous extracorporeal membrane oxygenation in an extern hospital before transfer to our tertiary center. After 13 days and various therapeutic approaches, including inhaled isoflurane therapy via an anesthetic-conserving device, the patient was decannulated and extubated 3 days later.

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

OBJECTIVES

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

DESIGN

Retrospective cohort study.

SETTING

A large tertiary urban care center.

PATIENTS

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

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

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

CONCLUSIONS

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

Characteristics of the pulmonary opacities on chest CT associated with difficulty in short-term liberation from veno-venous ECMO in patients with severe ARDS

BACKGROUND

It is clinically important to predict difficulty in short-term liberation from veno-venous extracorporeal membrane oxygenation (V-V ECMO) in patients with severe acute respiratory distress syndrome (ARDS) at the time of initiation of the support. The aim of this study was to identify the characteristics of pulmonary opacities on chest CT that is associated with difficulty in short-term liberation from V-V ECMO (< 14 days).

METHODS

This multicenter retrospective study was conducted in adult patients initiated on V-V ECMO for severe ARDS between January 2014 and June 2022. The pulmonary opacities on CT at the time of initiation of the ECMO support were evaluated in a blinded manner, focusing on the following three characteristics of the opacities: (1) their distribution (focal/diffuse on the dorso-ventral axis or unilateral/bilateral on the left-right axis); (2) their intensity (pure ground glass/pure consolidation/mixed pattern); and (3) the degree of fibroproliferation (signs of traction bronchiectasis or reticular opacities).

RESULTS

Among the 153 patients, 72 (47%) were successfully liberated from ECMO in the short term, while short-term liberation failed in the remaining 81 (53%) patients. Multivariate logistic regression analysis showed that the presence of mixed-pattern pulmonary opacities and signs of traction bronchiectasis, but not the distribution of the opacities, were independently associated with difficulty in short-term liberation (OR [95% CI]; 4.8 [1.4-16.5] and 3.9 [1.4-11.2], respectively).

CONCLUSIONS

The presence of a mixed pattern of the pulmonary opacities and signs of traction bronchiectasis on the chest CT were independently associated with difficulty in short-term liberation from V-V ECMO in severe ARDS patients.

Refractory Hypoxemia on VV-ECMO: Repetition of a Structured Approach Is Paramount: A Case Report

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is increasingly used to manage severe respiratory failure. Unfortunately, refractory hypoxemia often complicates VV-ECMO support. Both circuit- and patient-related etiologies can drive this, and a structured approach is necessary to diagnose and treat the condition. We present the case of a patient on VV-ECMO for acute respiratory distress syndrome who suffered from several distinct etiologies of refractory hypoxemia over a short timeframe. Frequent recalculation of cardiac output and oxygen delivery enabled early diagnosis and treatment of these conditions. We highlight the need for a structured and oft-repeated approach to this complex problem.

Extracorporeal Support for Acute Respiratory Distress Syndrome in Adults

Extracorporeal Support for ARDS in AdultsThere is a subset of patients who develop severe ARDS for whom supportive care with mechanical ventilation is insufficient or possibly injurious. The use of ECMO as an adjunct to treat these patients is reviewed.