Acute kidney injury in ECMO patients

Assessment of Nutritional Risk Scores (the Nutritional Risk Screening 2002 and Modified Nutrition Risk in Critically Ill Scores) as Predictors of Mortality in Critically Ill Patients on Extracorporeal Membrane Oxygenation

Nutritional risk is associated with intensive care unit (ICU) stay and mortality, the Nutritional Risk Screening 2002 (NRS 2002) and the modified Nutritional Risk in the Critically Ill (mNUTRIC) score are assessment instruments and useful in predicting the risk regarding mortality in ICU patients. Our aim was to assess the effects of mNUTRIC and NRS 2002 on mortality in patients on extracorporeal membrane oxygenation (ECMO). A retrospective cohort study was performed and 78 patients were included for final analysis. In the current study, the NRS 2002 and the mNUTRIC score within 24 hours before starting ECMO were applied to assess patients' nutritional status on ECMO and explore the relationship between nutritional status and patient outcomes. This study suggests that both mNUTRIC and NRS 2002 scores were found to be significant independent risk and prognostic factors for in-hospital and 90 day morality among ECMO patients based on multivariable logistic regression analysis ( p < 0.05), with those in the high-risk group having higher in-hospital and 90 day mortality rates than those identified as being at low risk ( p < 0.001). In comparison to the NRS 2002 score, the mNUTRIC score demonstrated a superior prognostic ability in ECMO patients.

Outcomes of Adult Patients With COVID-19 Transitioning From Venovenous to Venoarterial or Hybrid Extracorporeal Membrane Oxygenation in the Extracorporeal Life Support Organization Registry

This retrospective analysis of the Extracorporeal Life Support Organization (ELSO) registry evaluates the outcomes and identifies risk factors associated with conversion from initial venovenous extracorporeal membrane oxygenation (ECMO) support to venoarterial or hybrid ECMO in patients with coronavirus disease 2019 (COVID-19). We collected deidentified data on all adult patients (≥18 years old) diagnosed with COVID who received venovenous extracorporeal membrane oxygenation between March 2020 and November 2022. Patients initially placed on an ECMO configuration other than venovenous (VV) ECMO were excluded from the analysis. Our analysis included data from 12,850 patients, of which 393 (3.1%) transitioned from VV ECMO to an alternative mode. The primary outcome measure was in-hospital mortality, and the conversion group exhibited a higher in-hospital mortality rate. We also examined baseline variables, including demographic information, biochemical labs, and inotrope requirements. Univariate analysis revealed that pre-ECMO arrest, the need for renal replacement therapy, and the use of inotropic agents, particularly milrinone, were strongly associated with the risk of conversion. Notably, even after implementing a 3:1 propensity score matching, the impact of conversion on both mortality and complications remained substantial. Our study underscores an elevated risk of mortality for COVID-19 patients initially treated with VV ECMO who subsequently require conversion to VA-ECMO or hybrid ECMO.

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.

Perioperative Extracorporeal Cardiopulmonary Resuscitation in Adult Patients: A Review for the Perioperative Physician

The use of extracorporeal cardiopulmonary resuscitation for refractory cardiac arrest has grown rapidly over the previous decade. Considerations for the implementation and management of extracorporeal cardiopulmonary resuscitation are presented for the perioperative physician.

Concurrent use of continuous kidney replacement therapy during extracorporeal membrane oxygenation: what pediatric nephrologists need to know-PCRRT-ICONIC practice points

Extracorporeal membrane oxygenation (ECMO) provides temporary cardiorespiratory support for neonatal, pediatric, and adult patients when traditional management has failed. This lifesaving therapy has intrinsic risks, including the development of a robust inflammatory response, acute kidney injury (AKI), fluid overload (FO), and blood loss via consumption and coagulopathy. Continuous kidney replacement therapy (CKRT) has been proposed to reduce these side effects by mitigating the host inflammatory response and controlling FO, improving outcomes in patients requiring ECMO. The Pediatric Continuous Renal Replacement Therapy (PCRRT) Workgroup and the International Collaboration of Nephrologists and Intensivists for Critical Care Children (ICONIC) met to highlight current practice standards for ECMO use within the pediatric population. This review discusses ECMO modalities, the pathophysiology of inflammation during an ECMO run, its adverse effects, various anticoagulation strategies, and the technical aspects and outcomes of implementing CKRT during ECMO in neonatal and pediatric populations. Consensus practice points and guidelines are summarized. ECMO should be utilized in patients with severe acute respiratory failure despite the use of conventional treatment modalities. The Extracorporeal Life Support Organization (ELSO) offers guidelines for ECMO initiation and management while maintaining a clinical registry of over 195,000 patients to assess outcomes and complications. Monitoring and preventing fluid overload during ECMO and CKRT are imperative to reduce mortality risk. Clinical evidence, resources, and experience of the nephrologist and healthcare team should guide the selection of ECMO circuit.

Vasoactive-Inotropic Score as a Promising Predictor of Acute Kidney Injury in Adult Patients Requiring Extracorporeal Membrane Oxygenation

Acute kidney injury (AKI) is a common complication in patients supported by extracorporeal membrane oxygenation (ECMO). Vasoactive-Inotropic Score (VIS) serves as an indicator of the extent of cardiovascular drug support provided. Our objective is to assess the relationship between the VIS and ECMO-associated AKI (EAKI). This single-center retrospective study extracted adult patients treated with ECMO between August 2016 and September 2022 from an intensive care unit (ICU) in a university hospital. A total of 126 patients requiring ECMO support were included in the study, of which 76% developed AKI. Multivariate logistic regression analysis identified VIS-max Day1 (odds ratio [OR]: 1.025, 95% confidence interval [CI]: 1.007-1.044, p = 0.006), VIS-max Day2 (OR: 1.038, 95% CI: 1.007-1.069, p = 0.015), VIS-mean Day1 (OR: 1.048, 95% CI: 1.013-1.084, p = 0.007), and VIS-mean Day2 (OR: 1.059, 95% CI: 1.014-1.107, p = 0.010) as independent risk factors for EAKI. VIS-max Day1 showing the best predictive effect (Area under the receiver operating characteristic curve (AUROC): 0.80, sensitivity: 71.87%, specificity: 80.00%) for EAKI with a cutoff value of 33.33. Surprisingly, VIS-mean Day2 was also excellent at predicting 7 day mortality (AUROC: 0.77, sensitivity: 87.50%, specificity: 56.38%) with a cutoff value of 8.67. In conclusion, VIS could independently predict EAKI and 7 day mortality in patients with ECMO implantation, which may help clinicians to recognize the poor prognosis in time for early intervention.

Kidney Increase Natriuresis but Not Glomerular Filtration Under Veno-venous ECMO, a Retrospective Study

PURPOSE

Acute kidney injury is a frequent complication of acute respiratory distress syndrome (ARDS). We aim to study the evolution of kidney function in patients presenting severe ARDS and requiring veno-venous extracorporeal membrane oxygenation (VV ECMO).

METHODS

We conducted a multicenter retrospective study, including adult patients requiring VV ECMO for ARDS. The primary outcome was the evolution of the serum creatinine level after VV ECMO initiation. Secondary outcomes were change in urine output, and urine biochemical parameters after VV ECMO initiation.

RESULTS

One hundred and two patients were included. VV ECMO was initiated after a median of 6 days of mechanical ventilation, mainly for ARDS caused by COVID-19 (73%). Serum creatinine level did not significantly differ after VV ECMO initiation (P = .20). VV ECMO was associated with a significant increase in daily urine output (+6.6 mL/kg/day, [3.8;9.3] P < .001), even after adjustment for potential confounding factors; with an increase in natriuresis. The increase in urine output under VV ECMO was associated with a reduced risk of receiving kidney replacement therapy (OR 0.4 [0.2;0.8], P = .026).

CONCLUSIONS

VV ECMO initiation in severe ARDS is associated with an increase in daily urine output and natriuresis, without change in glomerular filtration rate.

Acute Kidney Injury in Patients Undergoing Extracorporeal Membrane Oxygenation: A Retrospective Cohort Study

Aims and background

Extracorporeal membrane oxygenation (ECMO) is a mode of extracorporeal therapy to support oxygenation of patients with severe cardiac or respiratory failure. Studies have shown that acute kidney injury (AKI) can worsen the outcome in these patients. This study aims to assess the incidence and outcome of AKI in patients on ECMO support.

Materials and methods

This retrospective study included 64 patients who underwent ECMO for more than 24 hours. Patients who died within 48 hours of initiation of ECMO and patients with end-stage renal disease (ESRD) on maintenance hemodialysis were excluded. Acute kidney injury was diagnosed and categorized according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria.

Results

Of the 64 patients studied, 38 patients (59.38%) developed AKI and 17 patients (44.73%) among them developed AKI within 24 hours of initiation of ECMO. Age, Acute Physiology and Chronic Health Evaluation (APACHE-II) score, hypertension, use of nephrotoxic agents, inotropic support, and poor cardiac function were the risk factors associated with the development of AKI. Diabetes mellitus, type of ECMO used, and duration of ECMO were not found to be risk factors for AKI. Renal replacement therapy was initiated in 31 patients (81.58%). The overall mortality in the whole group was 67.19%, while it was 81.58% among the patients with AKI.

Conclusion

Acute kidney injury was found to be an independent risk factor for mortality in patients on ECMO. Early identification of the risk factors for AKI and management may help to improve the survival rate.

Clinical significance

The occurrence of AKI among patients on ECMO support increases the risk of mortality significantly. Hence, measures to prevent AKI, as well as early detection and appropriate management of AKI, would improve patient outcomes.

How to cite this article

Surjit A, Prasannan B, Abraham J, Balagopal A, Unni VA. Acute Kidney Injury in Patients Undergoing Extracorporeal Membrane Oxygenation: A Retrospective Cohort Study. Indian J Crit Care Med 2024;28(1):26-29.

Use of Extracorporeal Membrane Oxygenation for Primary Graft Dysfunction After Cardiac Transplantation: Results of an A Priori Ventless Approach

Primary graft dysfunction (PGD) after cardiac transplantation is a devastating complication with increasing frequency lately in the setting of donation after circulatory death (DCD). Severe PGD is commonly treated with extracorporeal membrane oxygenation (ECMO) using central or peripheral cannulation. We retrospectively reviewed the outcomes of PGD after cardiac transplantation requiring ECMO support at our center from 2015 to 2020, focused on our now preferential approach using peripheral cannulation without a priori venting. During the study period, 255 patients underwent heart transplantation at our center and 26 (10.2%) of them required ECMO for PGD. Of 24 patients cannulated peripherally 19 (79%) were alive at 30 days and 17 (71%) 1 year after transplant; two additional patients underwent central ECMO cannulation due to unfavorable size of femoral vessels and concern for limb ischemia. Successful decannulation with full graft function recovery occurred in 22 of 24 (92%) patients cannulated peripherally. Six of them had an indwelling intra-aortic balloon pump placed before the transplantation. None of the other 18 patients received a ventricular vent. In conclusion, the use of an a priori peripheral and ventless ECMO approach in patients with PGD after heart transplant is an effective strategy associated with high rates of graft recovery and survival.

Early renal recovery after acute kidney injury in patients on venoarterial extracorporeal membrane oxygenation: A retrospective study

PURPOSE

The impact of VA-ECMO on early renal recovery (within 7 days after ECMO onset) in patients with pre-ECMO acute kidney injury and cardiogenic shock is unknown.

MATERIAL AND METHODS

This retrospective single-center study included adult patients with cardiogenic shock rescued by VA-ECMO and severe AKI occurring before ECMO implantation (pre-ECMO AKI). Patients with early renal recovery (defined as at least a 50% decrease in peak serum creatinine or weaning from renal replacement therapy) were compared to patients without early renal recovery.

RESULTS

During 7 years, 145 patients with severe pre-ECMO AKI were included. Eighty-two patients had no early renal recovery whereas 63 had early renal recovery within 7 days after VA-ECMO onset. The median time to early renal recovery was 4 (3,6) days. Nephrotoxic antibiotics (HR = 0.35 [95% CI, 0.21-0.59], p < 0.001), median fluid balance during the first 7 days of VA-ECMO (HR = 0.77 [95% CI, 0.64-0.93], p = 0.008), pre-ECMO AKI stage 3 (HR = 0.36 [95% CI, 0.20-0.64], p < 0.001) and median vasoactive-inotropic score (HR = 0.99 [95% CI, 0.98,1.00], p = 0.035) were independently associated with no early renal recovery.

CONCLUSIONS

Only 43% of patients with severe pre-ECMO AKI had early renal recovery after VA-ECMO initiation.

Early acute kidney injury and transition to renal replacement therapy in critically ill patients with SARS-CoV-2 requiring veno-venous extracorporeal membrane oxygenation

BACKGROUND

Critically ill patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requiring veno-venous extracorporeal membrane oxygenation (vv-ECMO) are at risk for acute kidney injury (AKI). Currently, the incidence of AKI and progression to kidney replacement therapy (RRT) in critically ill patients with vv-ECMO for severe COVID-19 and implications on outcome are still unclear.

METHODS

Retrospective analysis at the University Medical Center Hamburg-Eppendorf (Germany) between March 1st, 2020 and July 31st, 2021. Demographics, clinical parameters, AKI, type of organ support, length of ICU stay, mortality and severity scores were assessed.

RESULTS

Ninety-one critically ill patients with SARS-CoV-2 requiring ECMO were included. The median age of the study population was 57 (IQR 49-64) years and 67% (n = 61) were male. The median SAPS II and SOFA Score on admission were 40 (34-46) and 12 (10-14) points, respectively. We observed that 45% (n = 41) developed early-AKI, 38% (n = 35) late-AKI and 16% (n = 15) no AKI during the ICU stay. Overall, 70% (n = 64) of patients required RRT during the ICU stay, 93% with early-AKI and 74% with late-AKI. Risk factors for early-AKI were younger age (OR 0.94, 95% CI 0.90-0.99, p = 0.02) and SAPS II (OR 1.12, 95% CI 1.06-1.19, p < 0.001). Patients with and without RRT were comparable regarding baseline characteristics. SAPS II (41 vs. 37 points, p < 0.05) and SOFA score (13 vs. 12 points, p < 0.05) on admission were significantly higher in patients receiving RRT. The median duration of ICU (36 vs. 28 days, p = 0.27) stay was longer in patients with RRT. An ICU mortality rate in patients with RRT in 69% (n = 44) and in patients without RRT of 56% (n = 27) was observed (p = 0.23).

CONCLUSION

Critically ill patients with severe SARS-CoV-2 related ARDS requiring vv-ECMO are at high risk of early acute kidney injury. Early-AKI is associated with age and severity of illness, and presents with high need for RRT. Mortality in patients with RRT was comparable to patients without RRT.

Risk factors for mortality in surgical patients on combined continuous renal replacement therapy and extracorporeal membrane oxygenation: single-center retrospective study

OBJECTIVE

In patients receiving extracorporeal membrane oxygenation (ECMO), continuous renal replacement therapy (CRRT) is increasingly being used for renal replacement and fluid management. However, critically ill surgical patients receiving combined ECMO and CRRT tend to have a high mortality rate, and there are limited studies on this population. Therefore, we aimed to investigate the risk factors for mortality in surgical patients receiving combined ECMO and CRRT.

METHODS

Data of surgical patients who underwent ECMO between December 2013 and April 2023 were retrospectively reviewed. Univariate and multivariate logistic regression analysis were used to identify the risk variables. Receiver operating characteristic (ROC) curve analysis was used to determine the cutoff value of albumin and age to predict death.

RESULTS

A total of 199 patients on ECMO support were screened, of which 105 patients were included in the final analysis. Of 105 patients, 77 (73.33%) were treated with CRRT. Veno-arterial ECMO was performed in 97 cases (92.38%), and the rest were veno-venous ECMO (n = 8, 7.62%). Cardiovascular-related surgery was performed in the main patients (n = 86, 81.90%) and other types of surgery in 19 patients. In surgical patients on ECMO support, the logistic regression analysis showed that CRRT implantation, male sex, and age were the independent risks factors for mortality. Furthermore, the ROC curve analysis showed that age 48.5 years had the highest Youden index. In surgical patients on combined CRRT and ECMO, age, valvular heart disease, and albumin were the independent risk factors for prognosis. Albumin had the highest Youden index at a cutoff value of 39.95 g/L for predicting mortality, though the overall predictive value was modest (area under ROC 0.704). Age had the highest Youden index at a cutoff value of 48.5 years for predicting mortality.

CONCLUSIONS

In our cohort of surgical patients requiring ECMO, which consisted mostly of patients undergoing cardiovascular surgery requiring VA-ECMO, the need for CRRT was an independent risk factor for mortality. In the subset of patients on combined CRRT and ECMO, independent risk factors for mortality included higher age, lack of valvular heart disease, and lower serum albumin.

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.

Nomenclature of Extracorporeal Blood Purification Therapies for Acute Indications: The Nomenclature Standardization Conference

The development of new extracorporeal blood purification (EBP) techniques has led to increased application in clinical practice but also inconsistencies in nomenclature and misunderstanding. In November 2022, an international consensus conference was held to establish consensus on the terminology of EBP therapies. It was agreed to define EBP therapies as techniques that use an extracorporeal circuit to remove and/or modulate circulating substances to achieve physiological homeostasis, including support of the function of specific organs and/or detoxification. Specific acute EBP techniques include renal replacement therapy, isolated ultrafiltration, hemoadsorption, and plasma therapies, all of which can be applied in isolation and combination. This paper summarizes the proposed nomenclature of EBP therapies and serves as a framework for clinical practice and future research.

Predictors and Outcomes of Extracorporeal Membrane Oxygenation in COVID-19 Patients With ARDS: A Propensity-Matched Analysis of National Inpatient Sample

Extracorporeal membrane oxygenation (ECMO) is a significant treatment modality for COVID-19 patients on ventilators. The current data is limited for understanding the indicators and outcomes of ECMO in COVID-19 patients with acute respiratory distress syndrome (ARDS). The National Inpatient Sample (NIS) database from 2020 was queried in this study. Among 1,666,960 patients admitted with COVID-19, 99,785 (5.98%) patients developed ARDS, and 60,114 (60.2%) were placed on mechanical ventilation. Of these mechanically ventilated COVID-ARDS patients, 2580 (4.3%) were placed on ECMO. Patients with ECMO intervention had higher adjusted odds (aOR) of blood loss anemia (aOR 9.1, 95% CI: 6.16-13.5, propensity score-matched (PSM) 42% vs 5.4%, P < 0.001), major bleeding (aOR 3.79, 95% CI: 2.5-5.6, PSM 19.9% vs 5.9%, P < 0.001) and acute liver injury (aOR 1.7, 95% CI: 1.14-2.6 PSM 14% vs 6%, P = 0.009) compared to patients without ECMO intervention. However, in-hospital mortality, acute kidney injury, transfusions, acute MI, and cardiac arrest were insignificant. On subgroup analysis, patients placed on veno-arterial ECMO had higher odds of cardiogenic shock (aOR 13.4, CI 3.95-46, P < 0.0001), cardiac arrest (aOR 3.5, CI 1.45-8.47, P = 0.0057), acute congestive heart failure (aOR 4.18, CI 1.05-16.5, P = 0.042) and lower odds of major bleeding (aOR 0.26, CI 0.07-0.92). However, there was no significant difference in mortality, intracranial hemorrhage, and acute MI. Further studies are needed before considering COVID-19 ARDS patients for placement on ECMO.

Analysis of 24-hour Death Risk Factors in Circulatory Failure Patients Treated with Venoarterial Extracorporeal Membrane Oxygenation

OBJECTIVE

To explore the factors affecting short-term prognosis of circulatory failure patients undergoing venoarterial extracorporeal membrane oxygenation (VA-ECMO) treatment.

METHODS

A total of 136 patients undergoing VA-ECMO were enrolled in this study and subsequently divided into the death group (n=35) and the survival group (n=101) based on whether death occurred during hospitalisation. Extracorporeal membrane oxygenation (ECMO) running time, length of intensive care unit stay, length of hospital stay, costs, and ECMO complications were then compared between the two groups.

RESULTS

The average age of all patients undergoing ECMO was 47.64±16.78 years (53.2±16.20 years in the death group and 45.713±16.62 years in the survival group) (P=0.022). Patients in the survival group exhibited a clear downward trend in lactic acid value following ECMO treatment compared to those in the death group. Total hospitalisation stay was longer in the survival group (35 days) than in the death group (15.5 days) (P<0.001). In the analysis of ECMO complications, the incidence of neurological complications, renal failure, limb complications, and infection were higher in the death group than in the survival group (P<0.05 for all). Specifically, as a risk factor for patient survival and discharge, the occurrence of infection will lead to increased hospitalisation stays and costs (P<0.05 for both).

CONCLUSION

Complications such as kidney failure and infection are associated with in-hospital death, and ECMO-related complications should be actively prevented to improve the survival rate of VA-ECMO treatment.

Impact of renal complications on outcome in adult patients with acute fulminant myocarditis receiving venoarterial extracorporeal membrane oxygenation: an analysis of nationwide CSECLS database in China

BACKGROUND

Limited data are available on renal complications in patients with acute fulminant myocarditis (AFM) receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) support in China. To evaluate the impact of renal complications on outcomes in adult patients with AFM supported with VA-ECMO.

METHODS

Data were extracted from Chinese Society of ExtraCorporeal Life Support (CSECLS) Registry database. Adult patients who were diagnosed with AFM receiving VA-ECMO support in the database were included. The primary outcome was 30-day mortality in patients with AFM supported with VA-ECMO. Logistic regression model was used to examine the impact of renal complications on 30-day mortality by adjusting confounders.

RESULTS

A total of 202 patients were included. The median age was 38 years (IQR 29-48) and males (n = 103) represented 51.0% of the total accounted patients. The median ECMO duration was 142.9 h (IQR 112.1-188.8 h). 178 (88.1%) patients weaned from ECMO and 156 (71.9%) patients survived. 94(46.5%) patients developed renal complications while on ECMO course. Patients with renal complications had higher 30-day mortality (40.7% (37 of 94) vs 8.3% (9 of 108), P < 0.001) compared with those without. The development of renal complications was related to a 3.12-fold increase risk of 30-day mortality (adjusted OR 3.120, 95%CI 1.002-6.577, P = 0.049). Increasing age (adjusted OR1.025, 95% CI 1.008-1.298, P = 0.040) and higher SOFA score (adjusted OR 1.162, 95%CI 1.012-1.334, P = 0.034) were independent risk factors of renal complications.

CONCLUSIONS

Our findings demonstrated that patients with AFM receiving VA-ECMO at high risk of developing renal complications. Advancing age and higher SOFA score was associated with increased risk of developing renal complications. The onset of renal complications was significantly associated with 30-day mortality.

VA-ECMO Cardiac Support During Liver Transplant: A Case Report

Extracorporeal membrane oxygenation (ECMO) is a rescue therapy for cardiovascular collapse during and after liver transplantation (LT). According to the most recent guidelines, patients with severe cardiomyopathy are excluded from LT because of high-mortality risk during surgery. Intraoperative ECMO support could give these patients the opportunity to undergo LT by reducing the risk of heart failure and reperfusion syndrome. In this case report, we present a case of veno-arterial ECMO (VA-ECMO) support started before LT surgery in a patient with severe pulmonary hypertension, mitral valve steno-insufficiency, and right heart dysfunction. The presence of severe heart disease would have contraindicated LT, but simultaneous liver cirrhosis contraindicated mitral valve surgery, leaving the patient locked in a "Catch-22" state. The best solution was to perform LT with VA-ECMO support before, during, and after the surgery to reduce cardiac load and possible heart failure. LT was performed with good hemodynamic stability and the patient was successfully weaned from ECMO a few hours after surgery. At the 6 month follow-up, normal liver and kidney functions were recorded as well as an overall improvement of heart function; the patient successfully underwent mitral valve replacement and tricuspid annuloplasty 10 months after transplant and is now in good condition.

Interleukin-10: A Potential Pre-Cannulation Marker for Development of Acute Kidney Injury in Patients Receiving Veno-Arterial Extracorporeal Membrane Oxygenation

INTRODUCTION

Acute kidney injury (AKI) in patients treated with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is associated with high mortality. The objective of this study was to investigate whether cytokine levels before the initiation of ECMO treatment could predict AKI. We also aimed to investigate the impact of AKI on 30-day and 1-year mortality.

METHODS

Serum cytokine levels were analyzed in 100 consecutive VA-ECMO-treated patients at pre-cannulation, at 48 h post-cannulation, and at 8 days. Clinical data to establish the incidence and outcome of AKI after the start of ECMO was retrieved from the local ECMO registry.

SETTING

The study was conducted at tertiary care, university hospital. Participants included 100 patients treated with VA-ECMO.

INTERVENTIONS

The blood samples for cytokine analysis were collected before VA-ECMO treatment, at 48 h after VA-ECMO treatment was started, and at 8 days.

RESULTS

Pre-cannulation serum IL-10 levels were significantly higher in patients who developed AKI (212 [38.9, 620.7]) versus those who did not (49.0 [11.9, 102.2]; p = 0.007), and the development of AKI can be predicted by pre-cannulation IL-10 levels (p = 0.025, OR = 1.2 [1.02-1.32]). The development of AKI during ECMO treatment is associated with increased 30-day mortality (p = 0.049) compared to patients who did not develop AKI and had a pre-cannulation estimated glomerular filtration rate ≥ 45 mL/min. The 1-year survival rate for patients with AKI who survived the first 30 days of ECMO treatment is comparable to that of patients without AKI.

CONCLUSION

Increased pre-cannulation IL-10 levels are associated with the development of AKI during VA-ECMO support. AKI is associated with increased 30-day mortality compared to patients with no AKI and better renal function. However, patients with AKI who survive the first 30 days have a 1-year survival rate similar to those without AKI.

Managing the kidney - The role of continuous renal replacement therapy in neonatal and pediatric ECMO

Extracorporeal membrane oxygenation (ECMO) represents a lifesaving therapy utilized in in the most critically ill neonates and children with reversible cardiopulmonary failure. As a result of the severity of their critical illness these patients are among the highest risk populations for developing acute kidney injury (AKI) and disorders of fluid balance including the pathologic state of fluid overload (FO). In multiple studies AKI has been shown to occur commonly in 60-80% children treated with ECMO and is associated with adverse outcomes. In early studies evaluating ECMO in neonatal respiratory populations, the importance of fluid balance and the development of FO was recognized as an important contributor to adverse outcomes. Multiple single center studies and multicenter work have confirmed that FO occurs commonly across ECMO populations and is consistently associated with adverse outcomes. As a result of the high rates of AKI and the high rates of FO, continuous renal replacement therapy (CRRT) is increasingly utilized in neonatal and pediatric ECMO. In this state-of-the-art review, we cover the definitions, pathophysiology, incidence, and impact of AKI and FO in neonates and children supported with ECMO and summarize and appraise the evidence regarding the use of CRRT concurrently with ECMO. This review will cover the appropriate timing of this initiation, the options for providing CRRT with ECMO, overview of CRRT prescription, and the long-term implications of kidney support therapy in this population.

Haematological Trends and Transfusion during Adult Extracorporeal Membrane Oxygenation: A Single Centre Study

The temporal trends in haematological parameters and their associations with blood product transfusion requirements in patients supported with extracorporeal membrane oxygenation (ECMO) are poorly understood. We performed a retrospective data analysis to better understand the behaviour of haematological and coagulation parameters and their associations with transfusion requirements during ECMO.

METHODS

Patient demographics, haematological and coagulation parameters, plasma haemoglobin and fibrinogen concentrations, platelet count, the international normalised ratio (INR), the activated partial thromboplastin time (APTT), and blood product transfusion data from 138 patients who received ECMO in a single high-volume centre were analysed.

RESULTS

Ninety-two patients received venoarterial (VA) ECMO and 46 patients received venovenous (VV) ECMO. The median (IQR) duration of VA, and VV ECMO was 8 (5-13) days and 13 (8-23) days, respectively. There were significant reductions in haemoglobin, the platelet count, and the fibrinogen concentration upon initiation of ECMO. On average, over time, patients on VV ECMO had platelet counts 44 × 109/L higher than those on VA ECMO (p ≤ 0.001). Fibrinogen and APTT did not vary significantly based on the mode of ECMO (p = 0.55 and p = 0.072, respectively). A platelet count < 50 × 109/L or a fibrinogen level < 1.8 g/L was associated with 50% chance of PRBC transfusion, regardless of the ECMO type, and packed red blood cell (PRBC) transfusion was more common with VA ECMO. APTT was predictive of the transfusion requirement, and the decrement in APTT was discriminatory between VVECMO survivors and nonsurvivors.

CONCLUSION

ECMO support is associated with reductions in haemoglobin, platelet count, and fibrinogen. Patients supported with VA ECMO are more likely to receive a PRBC transfusion compared to those on VV ECMO. Thrombocytopaenia, hypofibrinogenaemia, and anticoagulation effect the likelihood of requiring PRBC transfusion. Further research is needed to define optimal blood management during ECMO, including appropriate transfusion triggers and the anticoagulation intensity.

Effect of flow change on brain injury during an experimental model of differential hypoxaemia in cardiogenic shock supported by extracorporeal membrane oxygenation

Differential hypoxaemia (DH) is common in patients supported by femoral veno-arterial extracorporeal membrane oxygenation (V-A ECMO) and can cause cerebral hypoxaemia. To date, no models have studied the direct impact of flow on cerebral damage. We investigated the impact of V-A ECMO flow on brain injury in an ovine model of DH. After inducing severe cardiorespiratory failure and providing ECMO support, we randomised six sheep into two groups: low flow (LF) in which ECMO was set at 2.5 L min-1 ensuring that the brain was entirely perfused by the native heart and lungs, and high flow (HF) in which ECMO was set at 4.5 L min-1 ensuring that the brain was at least partially perfused by ECMO. We used invasive (oxygenation tension-PbTO2, and cerebral microdialysis) and non-invasive (near infrared spectroscopy-NIRS) neuromonitoring, and euthanised animals after five hours for histological analysis. Cerebral oxygenation was significantly improved in the HF group as shown by higher PbTO2 levels (+ 215% vs - 58%, p = 0.043) and NIRS (67 ± 5% vs 49 ± 4%, p = 0.003). The HF group showed significantly less severe brain injury than the LF group in terms of neuronal shrinkage, congestion and perivascular oedema (p < 0.0001). Cerebral microdialysis values in the LF group all reached the pathological thresholds, even though no statistical difference was found between the two groups. Differential hypoxaemia can lead to cerebral damage after only a few hours and mandates a thorough neuromonitoring of patients. An increase in ECMO flow was an effective strategy to reduce such damages.

Predictors of Mortality in Patients With Refractory Cardiac Arrest Supported With VA-ECMO: A Systematic Review and a Meta-Analysis

Cardiac arrest (CA) is associated with high mortality rate, ranging between 75% and 93%. Given its significance, venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been used for end-organs perfusion and to maintain adequate oxygenation as a life-saving option in refractory CA. The predictors for the success of VA-ECMO in this setting have not been established yet. In this meta-analysis, we aim to identify the variables associated with increased mortality in patients with CA supported with VA-ECMO. We conducted a systematic review and meta-analysis to evaluate mortality-predicting factors in patients with CA supported with VA-ECMO that were published between January 2000 and July 2022. To identify relevant articles, the MEDLINE (Pubmed, Ovid) and Cochrane Databases were queried with various combinations of our prespecified keywords, including VA-ECMO, CA, and mortality predictors. We performed a meta-analysis using a random-effects model to calculate the odds ratio (OR). We retrieved a total of 4476 records, out of which we included 10 observational studies in our study. A total of 931 patients were included in our study with the age range of 47-68 years, predominantly males (63.9%). The overall mortality was 69.4%. The predictors for mortality were age >65 (OR 4.61, 95% CI 1.63-13.03, P < 0.01), history of chronic kidney disease (OR 2.42, 95% CI 1.37-4.28, P < 0.01), cardiopulmonary resuscitation duration prior to ECMO > 40 minutes (OR 6.62 [95% CI 1.39, 9.02], P < 0.01), having an initial nonshockable rhythm (OR 2.62 [95% CI 1.85, 3.70], P < 0.01) and sequential organ failure assessment score >14 (OR 12.29, 95% CI 2.71-55.74, P <0.01). Regarding blood work, an increase in lactate by 5 mmol/L increased the odds of mortality by 121% (2 studies; OR 2.21 [95% CI 1.26, 3.86], P < 0.01; I2 = 0%) while the increase in lactate by 1 mmol/L increases odd of mortality by 15% (2 studies, OR 1.15 [95% CI 1.02, 1.31], P = 0.03, I = 0%), and an increase in creatinine by 1 mg/dL increased the odds of mortality by 225% (1 study; OR 3.25 [95% CI 1.22, 8.7], P = 0.02). Albumin was protective as for each 1 g/dL increase, the odds of mortality decreased by 68% (1 study; OR 0.32 [95% CI 0.14, 0.74], P < 0.01). Refractory CA requiring VA-ECMO has a high mortality. Predictors of mortality include age >65, history of chronic kidney disease, cardiopulmonary resuscitation duration prior to ECMO > 40 minutes, initial rhythm being non-shockable and Sequential Organ Failure Assessment score >14.

Veno-venous extracorporeal membrane oxygenation for the treatment of respiratory compromise

Extracorporeal membrane oxygenation for the purpose of intervening upon profound cardiovascular or pulmonary compromise has proven to be a worthy intervention. Technological advancements have allowed this mode of therapy to become more effective and widespread. Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is a commonly used strategy to help manage patients with pulmonary dysfunction refractory to traditional management methods. This review intends to focus upon common indications and the clinical considerations for the institution of VV-ECMO as well as some of its known complications.

Planned Extracorporeal Life Support Employment during Liver Transplantation: The Potential of ECMO and CRRT as Preventive Therapies-Case Reports and Literature Review

Liver Transplantation (LT) has become the gold standard treatment for End-Stage Liver Disease (ESLD). One of the main strategies to manage life-threatening complications, such as cardio-respiratory failure, is Extracorporeal Membrane Oxygenation (ECMO) in the peri-transplantation period, with different configurations of the technique and in combination with other extracorporeal care devices such as Continuous Renal Replacement Therapy (CRRT). This retrospective study includes three clinical cases of planned ECMO support strategies in LT and evaluates their application compared with current literature exploring PubMed/Medline. The three LT supported with ECMO and CRRT were performed at IRCCS Polyclinic S. Orsola-Malpighi, Bologna. All three cases of patients with compromised organ function analysed produced positive outcomes. The planned use of ECMO and CRRT support in peri-transplantation has allowed the patients to overcome contraindications and successfully undergo LT. In recent years, only a few reports have documented successful LT outcomes performed with intraoperative ECMO in critically ESLD patients. However, the management of LT with ECMO and/or CRRT assistance is an emerging challenge, with the need for more published evidence on this topic to guide treatment choices in patients with severe, acute and reversible respiratory and cardiovascular failure after LT.

Higher Rates of Dialysis and Subsequent Mortality in the New Allocation Era for Heart Transplants

BACKGROUND

In 2018, a United Network for Organ Sharing (UNOS) policy change increased prioritization of patients bridged with temporary mechanical circulatory support devices, such as venoarterial ECMO, for cardiac transplantation. Considering increased waitlist acuity, we sought to characterize whether this was associated with an increased risk for development of postoperative acute renal failure requiring dialysis (AKI-D) and risk of death after transplantation.

METHODS

Dialysis-naive adults receiving single-organ heart transplant between November 2009 and February 2020 were stratified by receipt of AKI-D. Era 1 and era 2 were defined by the periods of UNOS allocation before and after policy change, respectively. Multivariable logistic regression was performed to determine risk factors for AKI-D. Rates of AKI-D were compared by propensity score-matched cohorts. Survival was compared by Kaplan-Meier analysis.

RESULTS

A total of 20 698 patients were included. Venoarterial ECMO use significantly increased in era 2 (5.6% vs 0.58%; P < .01). Overall prevalence of AKI-D was greater in era 2 (13.5% vs 10.2%; P < .01). Use of preoperative ECMO, intra-aortic balloon pump, and ventilators and longer ischemia times were identified as independent risk factors for development of AKI-D. Five- and 10-year survival rates were significantly decreased for patients with AKI-D. There was no short-term survival difference of patients with AKI-D between era 2 and the more contemporary era 1.

CONCLUSIONS

Patients in whom AKI-D develops after transplantation have significantly worse short- and long-term outcomes. Preoperative use of ECMO, preoperative ventilator support, and longer ischemia times are risk factors for development of AKI-D, and their prevalence has increased since the allocation policy change.

ECMO Retrieval Program: What Have We Learned So Far

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used for patients with cardiogenic shock or cardiac arrest. However, survival rates remain low. It is unclear to what extent ECMO patients benefit from the ECMO team learning curve. Therefore, we aimed to analyze our mobile ECMO program patients from the past seven years to evaluate if a learning curve benefits patients’ outcomes. We analyzed 111 patients from our databank who were supported with a VA-ECMO and brought to our hospital from January 2015 to December 2021. Patients were divided into two groups: survival (n = 70) and non-survival (n = 41). As expected, complications after ECMO implantation were more severe in the non-survivor group. The incidence of thromboembolic events (p = 0.002), hepatic failure (p < 0.001), renal failure (p = 0.002), dialysis (p = 0.002) and systemic inflammatory response syndrome (SIRS, p = 0.044) occurred significantly more often compared with the survivor group. We were able to show that despite our extensive experience in terms of ECMO retrieval program the high mortality and morbidity rates stay fairly the same over the years. This displays that we have to focus even more on patient selection and ECMO indication.

NEUROLOGIC IMPAIRMENT IN PATIENTS WITH EXTRACORPOREAL CARDIOPULMONARY RESUSCITATION SUPPORT: CLINICAL FEATURES AND LONG-TERM OUTCOMES

ABSTRACT

Introduction: The present study aimed to explore the clinical features and long-term outcomes associated with neurologic impairment in patients with cardiac arrest (CA) who received extracorporeal cardiopulmonary resuscitation (ECPR). Methods: A total of 37 adult CA patients who underwent venoarterial extracorporeal membrane oxygenation and were admitted to our department between January 2015 and February 2022 were divided according to neurologic impairment. Baseline and CPR- and ECMO-related characteristics were compared between the two groups. Long-term neurologic outcomes were collected via telephone follow-ups. Results: Twenty-four (64.9%) ECPR-supported patients developed neurologic impairments. The two groups differed significantly in median age (P = 0.026), proportion of intra-aortic balloon pump (IABP) support (P = 0.011), proportion of continuous renal replacement therapy (P = 0.025), and median serum creatinine (Cr) level (P = 0.012) pre-ECMO. The 28-day mortality (P = 0.001), hospital mortality (P = 0.003), median duration from CA to restoration of spontaneous circulation (P = 0.029), proportion of patients with nonpulsatile perfusion (NP) >12 hours (P = 0.040), and median ECMO duration (P = 0.047) were higher in the neurologic impairment group. In contrast, the group without neurologic impairment exhibited a longer median intensive care unit length of stay (P = 0.047), longer median hospital LOS (P = 0.031), and more successful ECMO weaning (P = 0.049). Moreover, NP >12 hours combined with IABP support (odds ratio [OR], 14.769; 95% confidence interval [CI], 1.417~153.889; P = 0.024) and serum Cr level (OR, 1.028; 95% CI, 1.001~1.056; P = 0.043) were independent risk factors for neurologic impairment. Furthermore, neurologic impairment was associated with significantly worse 90-day survival (hazards ratio, 4.218; 95% CI, 1.745~10.2; P = 0.0014). Conclusions: The incidence of neurologic impairment was higher in patients who received ECPR and was closely related to 28-day mortality and discharge survival. NP >12 hours combined with IABP support and serum Cr levels were independent risk factors for neurologic impairments in ECPR-supported patients. Neurologic impairment significantly adversely affected the long-term outcomes of ECPR-supported patients after discharge.

Long-term outcomes in patients who received veno-venous extracorporeal membrane oxygenation and renal replacement therapy: a retrospective cohort study

Background

Acute kidney injury (AKI) is a frequent complication in patients with severe respiratory failure receiving extracorporeal membrane oxygenation (ECMO). However, little is known of long-term kidney function in ECMO survivors. We aimed to assess the long-term mortality and kidney outcomes in adult patients treated with veno-venous ECMO (VV-ECMO).

Methods

This was a single-centre retrospective study of adult patients (≥ 18 years old) who were treated with VV-ECMO at a commissioned ECMO centre in the UK between 1st September 2010, and 30th November 2016. AKI was defined and staged using the serum creatinine and urine output criteria of the Kidney Diseases: Improving Global Outcomes (KDIGO) classification. The primary outcome was 1-year mortality. Secondary outcomes were long-term mortality (up to March 2020), 1-year incidence of end-stage kidney disease (ESKD) or chronic kidney disease (CKD) among AKI patients who received renal replacement therapy (AKI-RRT), AKI patients who did not receive RRT (AKI-no RRT) and patients without AKI (non-AKI).

Results

A total of 300 patients [57% male; median age 44.5; interquartile range (IQR) 34–54] were included in the final analysis. Past medical histories included diabetes (12%), hypertension (17%), and CKD (2.3%). The main cause of severe respiratory failure was pulmonary infection (72%). AKI occurred in 230 patients (76.7%) and 59.3% received renal replacement therapy (RRT). One-year mortality was 32% in AKI-RRT patients vs. 21.4% in non-AKI patients (p = 0.014). The median follow-up time was 4.35 years. Patients who received RRT had a higher risk of 1-year mortality than those who did not receive RRT (adjusted HR 1.80, 95% CI 1.06, 3.06; p = 0.029). ESKD occurred in 3 patients, all of whom were in the AKI-RRT group. At 1-year, 41.2% of survivors had serum creatinine results available. Among these, CKD was prevalent in 33.3% of AKI-RRT patients vs. 4.3% in non-AKI patients (p = 0.004).

Conclusions

VV-EMCO patients with AKI-RRT had high long-term mortality. Monitoring of kidney function after hospital discharge was poor. In patients with follow-up creatinine results available, the CKD prevalence was high at 1 year, especially in AKI-RRT patients. More awareness about this serious long-term complication and appropriate follow-up interventions are required.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01046-0.

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

OBJECTIVES

Despite increasing use and promising outcomes, venovenous extracorporeal membrane oxygenation (V-V ECMO) introduces the risk of a number of complications across the spectrum of ECMO care. This narrative review describes the variety of short- and long-term complications that can occur during treatment with ECMO and how patient selection and management decisions may influence the risk of these complications.

DATA SOURCES

English language articles were identified in PubMed using phrases related to V-V ECMO, acute respiratory distress syndrome, severe respiratory failure, and complications.

STUDY SELECTION

Original research, review articles, commentaries, and published guidelines from the Extracorporeal Life support Organization were considered.

DATA EXTRACTION

Data from relevant literature were identified, reviewed, and integrated into a concise narrative review.

DATA SYNTHESIS

Selecting patients for V-V ECMO exposes the patient to a number of complications. Adequate knowledge of these risks is needed to weigh them against the anticipated benefit of treatment. Timing of ECMO initiation and transfer to centers capable of providing ECMO affect patient outcomes. Choosing a configuration that insufficiently addresses the patient's physiologic deficit leads to consequences of inadequate physiologic support. Suboptimal mechanical ventilator management during ECMO may lead to worsening lung injury, delayed lung recovery, or ventilator-associated pneumonia. Premature decannulation from ECMO as lungs recover can lead to clinical worsening, and delayed decannulation can prolong exposure to complications unnecessarily. Short-term complications include bleeding, thrombosis, and hemolysis, renal and neurologic injury, concomitant infections, and technical and mechanical problems. Long-term complications reflect the physical, functional, and neurologic sequelae of critical illness. ECMO can introduce ethical and emotional challenges, particularly when bridging strategies fail.

CONCLUSIONS

V-V ECMO is associated with a number of complications. ECMO selection, timing of initiation, and management decisions impact the presence and severity of these potential harms.

Outcomes of critically ill coronavirus disease 2019 patients requiring kidney replacement therapy: A retrospective cohort study

BACKGROUND

Coronavirus disease 2019 (COVID-19) has resulted in high hospitalization rates worldwide. Acute kidney injury (AKI) in patients hospitalized for COVID-19 is frequent and associated with disease severity and poor outcome. The aim of this study was to investigate the incidence of kidney replacement therapy (KRT) in critically ill patients with COVID-19 and its implication on outcome.

METHODS

We retrospectively analyzed all COVID-19 patients admitted to the Department of Intensive Care Medicine at the University Medical Center Hamburg-Eppendorf (Germany) between 1 March 2020 and 31 July 2021. Demographics, clinical parameters, type of organ support, length of intensive care unit (ICU) stay, mortality and severity scores were assessed.

RESULTS

Three-hundred critically ill patients with COVID-19 were included. The median age of the study population was 61 (IQR 51-71) years and 66% (n = 198) were male. 73% (n = 219) of patients required invasive mechanical ventilation. Overall, 68% (n = 204) of patients suffered from acute respiratory distress syndrome and 30% (n = 91) required extracorporeal membrane oxygenation (ECMO). We found that 46% (n = 139) of patients required KRT. Septic shock (OR 11.818, 95% CI: 5.941-23.506, p < 0.001), higher simplified acute physiology scores (SAPS II) (OR 1.048, 95% CI: 1.014-1.084, p = 0.006) and vasopressor therapy (OR 5.475, 95% CI: 1.127-26.589, p = 0.035) were independently associated with the initiation of KRT. 61% (n = 85) of patients with and 18% (n = 29) without KRT died in the ICU (p < 0.001). Cox regression found that KRT was independently associated with mortality (HR 2.075, 95% CI: 1.342-3.208, p = 0.001) after adjusting for confounders.

CONCLUSION

Critically ill patients with COVID-19 are at high risk of acute kidney injury with about half of patients requiring KRT. The initiation of KRT was associated with high mortality.

A phased intervention bundle to decrease the mortality of patients with extracorporeal membrane oxygenation in intensive care unit

Aim

To evaluate whether a phased multidimensional intervention bundle would decrease the mortality of patients with extracorporeal membrane oxygenation (ECMO) and the complication incidence.

Materials and methods

We conducted a prospective observational study in comparison with a retrospective control group in six intensive care units (ICUs) in China. Patients older than 18 years supported with ECMO between March 2018 to March 2022 were included in the study. A phased intervention bundle to improve the outcome of patients with ECMO was developed and implemented. Multivariable logistic regression modeling was used to compare the mortality of patients with ECMO and the complication incidence before, during, and up to 18 months after implementation of the intervention bundle.

Results

The cohort included 297 patients in 6 ICUs, mostly VA ECMO (68.7%) with a median (25th–75th percentile) duration in ECMO of 9.0 (4.0–15.0) days. The mean (SD) APECHII score was 24.1 (7.5). Overall, the mortality of ECMO decreased from 57.1% at baseline to 21.8% at 13–18 months after implementation of the study intervention (P < 0.001). In multivariable analysis, even after excluding the confounding factors, such as age, APECHII score, pre-ECMO lactate, and incidence of CRRT during ECMO, the intervention bundle still can decrease the mortality independently, which also remained true in the statistical analysis of V-V and V-A ECMO separately. Among all the ECMO-related complications, the incidence of bloodstream infection and bleeding decreased significantly at 13–18 months after implementation compared with the baseline. The CUSUM analysis revealed a typical learning curve with a point of inflection during the implementation of the bundle.

Conclusion

A phased multidimensional intervention bundle resulted in a large and sustained reduction in the mortality of ECMO that was maintained throughout the 18-month study period.

Clinical trial registration

[ClinicalTrials.gov], identifier [NCT05024786].

Early Levosimendan Administration Improved Weaning Success Rate in Extracorporeal Membrane Oxygenation in Patients With Cardiogenic Shock

Background

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been increasingly used in patients with refractory cardiogenic shock (CS) or out-of-hospital cardiac arrest. It is difficult to perform VA-ECMO weaning, which may cause circulatory failure and death. Levosimendan is an effective inotropic agent used to maintain cardiac output, has a long-lasting effect, and may have the potential benefit for VA-ECMO weaning. The study aimed to explore the relationship between the early use of levosimendan and the rate of VA-ECMO weaning failure in patients on VA-ECMO support for circulatory failure.

Methods

All patients who underwent VA-ECMO in our hospital for CS between January 2017 and December 2020 were recruited in this cohort study and divided into two groups: without and with levosimendan use. Levosimendan was used as an add-on to other inotropic agents as early as possible after VA-ECMO setting. The primary endpoint was VA-ECMO weaning success, which was defined as survival without events for 24 h after VA-ECMO withdrawl. The secondary outcomes were cardiovascular and all-cause mortality at the 30-day and 180-day follow-up periods post-VA-ECMO initialization.

Results

A total of 159 patients were recruited for our study; 113 patients were enrolled in the without levosimendan-use group and 46 patients were enrolled in the levosimendan-use group. In levosimendan-use group, the patients received levosimendan infusion within 24 h after VA-ECMO initialization. Similar hemodynamic parameters were noted between the two groups. Poorer left ventricular ejection fraction and a higher prevalence of intra-aortic balloon pumping were observed in the levosimendan group. An improved weaning rate (without vs. with: 48.7 vs. 82.6%; p < 0.001), lower in-hospital mortality rate (without vs. with: 68.1 vs. 43.5%; p = 0.007), and 180-day cardiovascular mortality (without vs. with: 75.3 vs. 43.2%; p < 0.001) were also noted. Patients administered with levosimendan also presented a lower rate of 30-day (without vs. with: 75.3 vs. 41.3%; p = 0.034) and 180-day (without vs. with: 77.0 vs. 43.2%; p < 0.001) all-cause mortality.

Conclusion

Early levosimendan administration may contribute to increasing the success rate of VA-ECMO weaning and may help to decrease CV and all-cause mortality.

Outcome of post-traumatic acute respiratory distress syndrome in young patients requiring extracorporeal membrane oxygenation (ECMO)

We aimed to evaluate the outcomes of post-traumatic acute respiratory distress syndrome (ARDS) in young patients with and without Extracorporeal membrane oxygenation (ECMO) support. A retrospective analysis was conducted for trauma patients who developed ARDS at a level I trauma facility between 2014 and 2020. Data were analyzed and compared between ECMO and non-ECMO group. We identified 85 patients with ARDS (22 patients had ECMO support and 63 matched patients managed by the conventional mechanical ventilation; 1:3 matching ratio). The two groups were comparable for age, sex, injury severity score, abbreviated injury score, shock index, SOFA score, and head injury. Kaplan Meier survival analysis showed that the survival in the ECMO group was initially close to that of the non-ECMO, however, during follow-up, the survival rate was better in the ECMO group, but did not reach statistical significance (Log-rank, p = 0.43 and Tarone-Ware, p = 0.37). Multivariable logistic regression analysis showed that acute kidney injury (AKI) (Odds ratio 13.03; 95% CI 3.17–53.54) and brain edema (Odds ratio 4.80; 95% CI 1.10–21.03) were independent predictors of mortality. Sub-analysis showed that in patients with severe Murray Lung Injury (MLI) scores, non-ECMO group had higher mortality than the ECMO group (100% vs 36.8%, p = 0.004). Although ARDS is uncommon in young trauma patients, it has a high mortality. ECMO therapy was used in a quarter of ARDS cases. AKI and brain edema were the predictors of mortality among ARDS patients. ECMO use did not worsen the outcome in trauma patients; however, the survival was better in those who had severe MLI and ECMO support. Further prospective study is needed to define the appropriate selection criteria for the use of ECMO to optimize the outcomes in trauma patients.

Trends, Advantages and Disadvantages in Combined Extracorporeal Lung and Kidney Support From a Technical Point of View

Extracorporeal membrane oxygenation (ECMO) provides pulmonary and/or cardiac support for critically ill patients. Due to their diseases, they are at high risk of developing acute kidney injury. In that case, continuous renal replacement therapy (CRRT) is applied to provide renal support and fluid management. The ECMO and CRRT circuits can be combined by an integrated or parallel approach. So far, all methods used for combined extracorporeal lung and kidney support present serious drawbacks. This includes not only high risks of circuit related complications such as bleeding, thrombus formation, and hemolysis, but also increase in technical workload and health care costs. In this sense, the development of a novel optimized artificial lung device with integrated renal support could offer important treatment benefits. Therefore, we conducted a review to provide technical background on existing techniques for extracorporeal lung and kidney support and give insight on important aspects to be addressed in the development of this novel highly integrated artificial lung device.

Extracorporeal Membrane Oxygenation—First Strategy for Acute Life-Threatening Pulmonary Embolism

Background

Both venoarterial extracorporeal membrane oxygenation (VA-ECMO) and percutaneous mechanical thrombectomy (PMT) are increasingly used to treat acute life-threatening pulmonary embolism (PE). However, there are little data regarding their effectiveness. This study aimed to present the short-term outcomes after managing nine patients with acute life-threatening massive or submassive PE by VA-ECMO with or without complemented PMT and propose a preliminary treatment algorithm.

Methods

This study was a single-center retrospective review of a prospectively maintained registry. It included nine consecutive patients with massive or submassive pulmonary embolism who underwent VA-ECMO for initial hemodynamic stabilization, with or without PMT, from August 2018 to November 2021.

Results

Mean patient age was 54.7 years. Four of nine patients (44.4%) required cardiopulmonary resuscitation before or during VA-ECMO cannulation. All cannulations (100%) were successfully performed percutaneously. Overall survival was 88.9% (8 of 9 patients). One patient died from a hemorrhagic stroke. Of the survivors, the median ECMO duration was 8 days in patients treated with ECMO alone and 4 days in those treated with EMCO and PMT. Five of nine patients (55.6%) required concomitant PMT to address persistent right heart dysfunction, with the remaining survivors (44.4%) receiving VA-ECMO and anticoagulation alone. For survivors receiving VA-ECMO plus PMT, median hospital lengths of stay were 7 and 13 days, respectively.

Conclusions

An ECMO-first strategy complemented with PMT can be performed effectively and safely for acute life-threatening massive or submassive PE. VA-ECMO is feasible for initial stabilization, serving as a bridge to therapy primarily in inoperable patients with massive PE. Further evaluation in a larger cohort of patients is warranted to assess whether VA-ECMO plus PMT may offer an alternative or complementary therapy to thrombolysis or surgical thrombectomy.

Type of Research

Single-center retrospective review of a prospectively maintained registry.

Monitoring during extracorporeal membrane oxygenation

PURPOSE OF REVIEW

Extracorporeal membrane oxygenation (ECMO) offers advanced mechanical support to patients with severe acute respiratory and/or cardiac failure. Ensuring an adequate therapeutic approach as well as prevention of ECMO-associated complications, by means of timely liberation, forms an essential part of standard ECMO care and is only achievable through continuous monitoring and evaluation. This review focus on the cardiorespiratory monitoring tools that can be used to assess and titrate adequacy of ECMO therapy; as well as methods to assess readiness to wean and/or discontinue ECMO support.

RECENT FINDINGS

Surrogates of tissue perfusion and near infrared spectroscopy are not standards of care but may provide useful information in select patients. Echocardiography allows to determine cannulas position, evaluate cardiac structures, and function, and diagnose complications. Respiratory monitoring is mandatory to achieve lung protective ventilation and identify early lung recovery, surrogate measurements of respiratory effort and ECMO derived parameters are invaluable in optimally managing ECMO patients.

SUMMARY

Novel applications of existing monitoring modalities alongside evolving technological advances enable the advanced monitoring required for safe delivery of ECMO. Liberation trials are necessary to minimize time sensitive ECMO related complications; however, these have yet to be standardized.

Veno-Arterial Extracorporeal Membrane Oxygenation in Elective High-Risk Percutaneous Coronary Interventions

Background

The safety and feasibility of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) as mechanical circulatory support in high-risk percutaneous coronary intervention (HR-PCI) remain unclear.

Methods

This retrospective study included patients with complex and high-risk coronary artery disease who underwent elective PCI with VA-ECMO support pre-operatively during March 2019–December 2020. Rates of VA-ECMO-related complications, complications during PCI, death, myocardial infarction, and stroke during hospitalisation and 1-year post-operatively were analysed.

Results

Overall, 36 patients (average age: 63.6 ± 8.9 years) underwent PCI. The average duration of VA-ECMO support was 12.5 (range, 3.0–26.3) h. Intra-aortic balloon pump counterpulsation was used in 44.4% of patients. The SYNTAX score was 34.6 ± 8.4 pre-operatively and 10.8 ± 8.8 post-operatively (P < 0.001). Intraoperative complications included pericardial tamponade (N = 2, 5.6%), acute left-sided heart failure (N = 1, 2.8%), malignant arrhythmia requiring electrocardioversion (N = 2, 5.6%), and no deaths. Blood haemoglobin levels before PCI and 24 h after VA-ECMO withdrawal were 145.4 ± 20.2 g/L and 105.7 ± 21.7 g/L, respectively (P < 0.001). Outcomes during hospitalisation included death (N = 1, 2.8%), stroke (N = 1, 2.8%), lower limb ischaemia (N = 2, 5.6%), lower limb deep venous thrombosis (N = 1, 2.8%), cannulation site haematoma (N = 2, 5.6%), acute renal injury (N = 2, 5.6%), bacteraemia (N = 2, 5.6%), bleeding requiring blood transfusion (N = 5, 13.9%), and no recurrent myocardial infarctions. Within 1 year post-operatively, two patients (5.6%) were hospitalised for heart failure.

Conclusions

Veno-arterial extracorporeal membrane oxygenation mechanical circulation support during HR-PCI is a safe and feasible strategy for achieving revascularisation in complex and high-risk coronary artery lesions. VA-ECMO-related complications require special attention.

Integration of sustained low-efficiency dialysis into extracorporeal membrane oxygenation circuit in critically ill COVID-19 patients - a feasibility study

Background

Severe COVID‐19 can necessitate multiple organ support including veno‐venous extracorporeal membrane oxygenation (vvECMO) and renal replacement therapy. The therapy can be complicated by venous thromboembolism due to COVID‐19‐related hypercoagulability, thus restricting vascular access beyond the vvECMO cannula. Although continuous renal replacement therapy can be performed via a vvECMO circuit, studies addressing sustained low‐efficiency dialysis (SLED) integration into vvECMO circuits are scarce. Here we address the lack of evidence by evaluating feasibility of SLED integration into vvECMO circuits.

Methods

Retrospective cohort study on nine critically ill COVID‐19 patients, treated with integrated ECMO‐SLED on a single intensive care unit at a tertiary healthcare facility between December 2020 and November 2021. The SLED circuits were established between the accessory arterial oxygenator outlets of a double‐oxygenator vvECMO setup. Data on filter survival, quality of dialysis, and volume management were collected and compared with an internal control group receiving single SLED.

Results

This study demonstrates general feasibility of SLED integration into existing vvECMO circuits. Filter lifespans of ECMO‐SLED compared with single SLED are significantly prolonged (median 18.3 h vs. 10.3 h, p < 0.01). ECMO‐SLED treatment is furthermore able to sufficiently normalize creatinine, blood urea nitrogen, and serum sodium, and allows for adequate ultrafiltration rates.

Conclusions

We can show that ECMO‐SLED is practical, safe, results in adequate dialysis quality and enables sufficient electrolyte and volume management. Our data indicate that SLED devices can serve as potential alternative to continuous‐veno‐venous‐hemodialysis for integration in vvECMO circuits.

Renal Replacement Therapy for Patients Requiring Extracorporeal Membrane Oxygenation: A Multicenter International Survey

INTRODUCTION

Patients receiving extracorporeal membrane oxygenation (ECMO) often require renal replacement therapy (RRT). The challenge of inserting a dialysis catheter (DC) could be solved by direct connection of RRT lines on an ECMO circuit (DCRE) without published guidelines. This study aimed to describe the practice of RRT in patients on ECMO, including the DCRE as well as the perception and concerns related to this technique.

METHODS

An international survey was worldwide sent via email to professionals involved in the management of ECMO. Respondents always or often performing RRT via the ECMO circuit were classified in the ECMO group, and those using a DC were classified in the DC group.

RESULTS

From March 2019 to October 2019, 298 participants answered the questionnaire from 46 different countries. Only 28% were working in pediatric departments. Among the 165 participants commonly performing RRT in patients on ECMO, 100 (61%) performed mainly RRT via the ECMO circuit, and 65 (39%) performed RRT via DC. Pediatric practice and a longer experience were the only noticeable characteristics of the ECMO group. The most reported concern regarding DCRE was the risk of air embolism (n = 84, 28%), but the most encountered problem was unmanageable pressure alarms in RRT devices.

CONCLUSION

The present study showed significant heterogeneity in RRT practices in patients on ECMO. The lower experience of the DC group, the high rates of concerns toward DCRE, and pressure alarm issues suggested that protocols and training may overcome reluctance and technical difficulties.

Does delivering more dialysis improve clinical outcomes? What randomized controlled trials have shown

Some randomized controlled trials (RCTs) have sought to determine whether different dialysis techniques, dialysis doses and frequencies of treatment are able to improve clinical outcomes in end-stage kidney disease (ESKD). Virtually all of these RCTs were enacted on the premise that 'more' haemodialysis might improve clinical outcomes compared to 'conventional' haemodialysis. Aim of the present narrative review was to analyse these landmark RCTs by posing the following question: were their intervention strategies (i.e., earlier dialysis start, higher haemodialysis dose, intensive haemodialysis, increase in convective transport, starting haemodialysis with three sessions per week) able to improve clinical outcomes? The answer is no. There are at least two main reasons why many RCTs have failed to demonstrate the expected benefits thus far: (1) in general, RCTs included relatively small cohorts and short follow-ups, thus producing low event rates and limited statistical power; (2) the designs of these studies did not take into account that ESKD does not result from a single disease entity: it is a collection of different diseases and subtypes of kidney dysfunction. Patients with advanced kidney failure requiring dialysis treatment differ on a multitude of levels including residual kidney function, biochemical parameters (e.g., acid base balance, serum electrolytes, mineral and bone disorder), and volume overload. In conclusion, the different intervention strategies of the RCTs herein reviewed were not able to improve clinical outcomes of ESKD patients. Higher quality studies are needed to guide patients and clinicians in the decision-making process. Future RCTs should account for the heterogeneity of patients when considering inclusion/exclusion criteria and study design, and should a priori consider subgroup analyses to highlight specific subgroups that can benefit most from a particular intervention.