Extracorporeal Membrane Oxygenation Use in Cardiogenic Shock: Impact of Age on In-Hospital Mortality, Length of Stay, and Costs

Extracorporeal Membrane Oxygenation for Cardiac Arrest: Does Age Matter?

OBJECTIVES

The impact of age on hospital survival for patients treated with extracorporeal cardiopulmonary resuscitation (ECPR) for cardiac arrest (CA) is unknown. We sought to characterize the association between older age and hospital survival after ECPR, using a large international database.

DESIGN

Retrospective analysis of the Extracorporeal Life Support Organization registry.

PATIENTS

Patients 18 years old or older who underwent ECPR for CA between December 1, 2016, and October 31, 2020.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was adjusted odds ratio (aOR) of death after ECPR, analyzed by age group (18-49, 50-64, 65-74, and > 75 yr). A total of 5,120 patients met inclusion criteria. The median age was 57 years (interquartile range, 46-66 yr). There was a significantly lower aOR of survival for those 65-74 (0.68l 95% CI, 0.57-0.81) or those greater than 75 (0.54; 95% CI, 0.41-0.69), compared with 18-49. Patients 50-64 had a significantly higher aOR of survival compared with those 65-74 and greater than 75; however, there was no difference in survival between the two youngest groups (aOR, 0.91; 95% CI, 0.79-1.05). A sensitivity analysis using alternative age categories (18-64, 65-69, 70-74, and ≥ 75) demonstrated decreased odds of survival for age greater than or equal to 65 compared with patients younger than 65 (for age 65-69: odds ratio [OR], 0.71; 95% CI, 0.59-0.86; for age 70-74: OR, 0.84; 95% CI, 0.67-1.04; and for age ≥ 75: OR, 0.64; 95% CI, 0.50-0.81).

CONCLUSIONS

This investigation represents the largest analysis of the relationship of older age on ECPR outcomes. We found that the odds of hospital survival for patients with CA treated with ECPR diminishes with increasing age, with significantly decreased odds of survival after age 65, despite controlling for illness severity and comorbidities. However, findings from this observational data have significant limitations and further studies are needed to evaluate these findings prospectively.

Age and associated outcomes among patients receiving venoarterial extracorporeal membrane oxygenation-analysis of the Extracorporeal Life Support Organization registry

PURPOSE

Venoarterial extracorporeal membrane oxygenation (V-A ECMO) can be used to support severely ill patients with cardiogenic shock. While age is commonly used in patient selection, little is known regarding its association with outcomes in this population. We sought to evaluate the association between increasing age and outcomes following V-A ECMO.

METHODS

We used individual-level patient data from 440 centers in the international Extracorporeal Life Support Organization registry. We included all adult patients receiving V-A ECMO from 2017 to 2019. The primary outcome was hospital mortality. Secondary outcomes included a composite of complications following initiation of V-A ECMO. We conducted Bayesian analyses of the relationship between increasing age and outcomes of interest.

RESULTS

We included 15,172 patients receiving V-A ECMO. Of these, 8172 (53.9%) died in hospital. For the analysis conducted using weakly informed priors, and as compared to the reference category of age 18-29, the age bracket of 30-39 (odds ratio [OR] 0.94, 95% credible interval [CrI] 0.79-1.10) was not associated with hospital mortality, but age brackets 40-49 (odds ratio [OR] 1.26, 95% CrI: 1.08-1.47), 50-59 (OR 1.78, 95% CrI: 1.55-2.06), 60-69 (OR 2.24, 95% CrI: 1.94-2.59), 70-79 (OR 2.90, 95% CrI: 2.49-3.39) and ≥ 80 (OR 4.02, 95% CrI: 3.13-5.20) were independently associated with increasing hospital mortality. Similar results were found in the analysis conducted with an informative prior, as well as between increasing age and post-ECMO complications.

CONCLUSIONS

Among patients receiving V-A ECMO for cardiogenic shock, increasing age is strongly associated with increasing odds of death and complications, and this association emerges as early as 40 years of age.

Predicting Survival for Veno-Arterial ECMO Using Conditional Inference Trees-A Multicenter Study

BACKGROUND

Despite increasing use and understanding of the process, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy is still associated with considerable mortality. Personalized and quick survival predictions using machine learning methods can assist in clinical decision making before ECMO insertion.

METHODS

This is a multicenter study to develop and validate an easy-to-use prognostic model to predict in-hospital mortality of VA-ECMO therapy, using unbiased recursive partitioning with conditional inference trees. We compared two sets with different numbers of variables (small and comprehensive), all of which were available just before ECMO initiation. The area under the curve (AUC), the cross-validated Brier score, and the error rate were applied to assess model performance. Data were collected retrospectively between 2007 and 2019.

RESULTS

837 patients were eligible for this study; 679 patients in the derivation cohort (median (IQR) age 60 (49 to 69) years; 187 (28%) female patients) and a total of 158 patients in two external validation cohorts (median (IQR) age 57 (49 to 65) and 70 (63 to 76) years). For the small data set, the model showed a cross-validated error rate of 35.79% and an AUC of 0.70 (95% confidence interval from 0.66 to 0.74). In the comprehensive data set, the error rate was the same with a value of 35.35%, with an AUC of 0.71 (95% confidence interval from 0.67 to 0.75). The mean Brier scores of the two models were 0.210 (small data set) and 0.211 (comprehensive data set). External validation showed an error rate of 43% and AUC of 0.60 (95% confidence interval from 0.52 to 0.69) using the small tree and an error rate of 35% with an AUC of 0.63 (95% confidence interval from 0.54 to 0.72) using the comprehensive tree. There were large differences between the two validation sets.

CONCLUSIONS

Conditional inference trees are able to augment prognostic clinical decision making for patients undergoing ECMO treatment. They may provide a degree of accuracy in mortality prediction and prognostic stratification using readily available variables.

Age-related outcomes in patients with cardiogenic shock stratified by etiology

BACKGROUND

As a result of improved and novel treatment strategies, the spectrum of patients with cardiovascular disease is consistently changing. Overall, those patients are typically older and characterized by increased burden with comorbidities. Limited data on the prognostic impact of age in cardiogenic shock (CS) is available. Therefore, this study investigates the prognostic impact of age in patients with CS.

METHODS

From 2019 to 2021, consecutive patients with CS of any cause were included. The prognostic value of age (i.e., 60-80 years and > 80 years) was investigated for 30-day all-cause mortality. Spearman's correlations, Kaplan-Meier analyses, as well as multivariable Cox proportional regression analyses were performed for statistics. Subsequent risk assessment was performed based on the presence or absence of CS related to acute myocardial infarction (AMI).

RESULTS

223 CS patients were included with a median age of 77 years (interquartile range: 69-82 years). No significant difference in 30-day all-cause mortality was observed for both age-groups (54.6% vs. 63.4%, log-rank P = 0.169; HR = 1.273, 95% CI: 0.886-1.831, P = 0.192). In contrast, when analyzing subgroups stratified by CS-etiology, AMI-related CS patients of the group > 80 years showed an increased risk of 30-day all-cause mortality (78.1% vs. 60.0%, log-rank P = 0.032; HR = 1.635, 95% CI: 1.000-2.673, P = 0.050), which was still evident after multivariable adjustment (HR = 2.072, 95% CI: 1.174-3.656, P = 0.012).

CONCLUSIONS

Age was not associated with 30-day all-cause mortality in patients with CS of mixed etiology. However, increasing age was shown to be a significant predictor of increased mortality-risk in the subgroup of patients presenting with AMI-CS.

External validation of the REMEMBER score

Background

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) after coronary artery bypass grafting (CABG) is associated with high in-hospital mortality rates. The pRedicting mortality in patients undergoing venoarterial Extracorporeal MEMBrane oxygenation after coronary artEry bypass gRafting (REMEMBER) score has been created to predict in-hospital mortality in this subgroup of patients. The aim of this study is to externally validate the REMEMBER score.

Methods

All CABG patients who received VA-ECMO during or after the operation at our center between 01/2012 and 12/2021 were included in the analysis. Discrimination was assessed using concordance statistics, visualized by ROC curve analysis. Calibration-in-the-large and Calibration slope were tested separately.

Results

A total of 107 patients (male: n = 78, 72.9%) were included in this study. The in-hospital mortality rate in our cohort was 45.8% compared with 55% in the original study. The REMEMBER score median predicted mortality rate was 52% (76.9-36%). However, the REMEMBER score showed low discriminative ability [AUC: 0.623 (p = 0.0244; 95% CI = 0.524-0.715)] and inaccurate calibration (intercept = 0.25074; p = 0.0195; slope = 0.39504; p = 0.0303), indicating poor performance.

Conclusions

The REMEMBER score did not predict in-hospital mortality and was therefore not applicable in our cohort of patients. Additional external validation studies in a multicenter setting are therefore advisable.

Immune function of colon cancer associated miRNA and target genes

Introduction

Colon cancer is a complex disease that involves intricate interactions between cancer cells and theimmune microenvironment. MicroRNAs (miRNAs) have recently emerged as critical regulators of gene expression in cancer, including colon cancer. There is increasing evidence suggesting that miRNA dysregulation plays a crucial role in modulating the immune microenvironment of intestinal cancer. In particular, miRNAs regulate immune cell activation, differentiation, and function, as well as cytokine and chemokine production in intestinal cancer. It is urgent to fully investigate the potential role of intestinal cancer-related miRNAs in shaping the immune microenvironment.

Methods

Therefore, this paper aims to identify miRNAs that are potentially associated with colon cancer and regulate a large number of genes related to immune function. We explored the role of these genes in colon cancer patient prognosis, immune infiltration, and tumor purity based on data of 174 colon cancer patients though convolutional neural network, survival analysis and multiple analysis tools.

Results

Our findings suggest that miRNA regulated genes play important roles in CD4 memory resting cells, macrophages.M2, and Mast cell activated cells, and they are concentrated in the cytokinecytokine receptor interaction pathway.

Discussion

Our study enhances our understanding of the underlying mechanisms of intestinal cancer and provides new insights into the development of effective therapies. Additionally, identification of miRNA biomarkers could aid in diagnosis and prognosis, as well as guide personalized treatment strategies for patients with intestinal cancer.

The impact of preservation and recovery of renal function on survival after veno-arterial extracorporeal life support: A retrospective cohort study

BACKGROUND

Veno-arterial extracorporeal life support (V-A ECLS) has become a cornerstone in the management of critical cardiogenic shock, but it can also precipitate organ injury, e.g., acute kidney injury (AKI). Available studies highlight the effect of non-cardiac organ injury on patient outcomes. Only very little is known about the impact of non-cardiac organ recovery on patient survival. AKI occurs frequently during cardiogenic shock and carries a poor prognosis. We have developed descriptive models to hypothesize on the role of AKI severity versus that of recovery of renal function for patient survival.

METHODS

Retrospective, observational study including 175 patients who were successfully decannulated from V-A ECLS. We assessed AKI severity using the "Kidney Disease: Improving Global Outcomes" (KDIGO) criteria. We defined recovered or preserved renal function (RPRF) prior to decannulation from V-A ECLS as 0 (AKI with no improvement) or 1 (no AKI or AKI with improvement). We classified patient outcomes as alive or dead at hospital discharge.

RESULTS

78% (n = 138) of all patients survived hospital discharge of which 38% (n = 67) never developed AKI. After adjusting for shock severity and non-renal organ injury, RPRF emerged as an independent predictor of survival in both the overall cohort [OR (95% CI) - 4.11 (1.72-9.79)] and the AKI-only sub-cohort [OR (95% CI) - 5.18 (1.8-14.92)]. Neither maximum KDIGO stage nor KDIGO stage at the end of V-A ECLS was independently associated with survival.

CONCLUSIONS

Our model identifies RPRF, but not AKI severity, as an independent predictor of hospital survival in patients undergoing V-A ECLS for cardiogenic shock. We hypothesize that recovered or preserved non-cardiac organ function during V-A ECLS is crucial for patient survival.

Clinical picture of the duration of venoarterial extracorporeal membrane oxygenation: analysis from JROAD-DPC

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been widely used for critically ill patients all over the world; however, comprehensive survey regarding the relationship between VA-ECMO duration and prognosis is limited. We conducted a survey of VA-ECMO patients in the Japanese Registry of All Cardiac and Vascular Diseases-Diagnosis Procedure Combination (JROAD-DPC), which was a health insurance claim database study among cardiovascular centers associated with the Japan Circulation Society, between April 2012 and March 2016. Out of 13,542 VA-ECMO patients, we analyzed 5766 cardiovascular patients treated with VA-ECMO. 68% patients used VA-ECMO only for 1 day and 93% had VA-ECMO terminated within 1 week. In multivariate analysis, the hazard ratio of 1-day support was significantly high at 1.72 (95% confidence intervals; 95% CI 1.53-1.95) (p < 0.001), while that of 2-day [0.60 (95% CI 0.49-0.73)], 3-day [0.75 (95% CI 0.60-0.94)], 4-day [0.43 (95% CI 0.31-0.60)] and 5-day support [0.62 (95% CI 0.44-0.86)] was significantly low. Comprehensive database analysis of JROAD-DPC revealed that cardiovascular patients who were supported with VA-ECMO for 2-5 days showed lower mortality. The optimal VA-ECMO support window should be investigated in further studies.

Trends in Veno-Arterial Extracorporeal Life Support With and Without an Impella or Intra-Aortic Balloon Pump for Cardiogenic Shock

Background Mechanical circulatory support devices, such as the intra-aortic balloon pump (IABP) and Impella, are often used in patients on veno-arterial extracorporeal life support (VA-ECLS) with cardiogenic shock despite limited supporting clinical trial data. Methods and Results Hospitalizations for cardiogenic shock from 2016 to 2018 were identified from the National Inpatient Sample. Trends in the use of VA-ECLS with and without an IABP or Impella were assessed semiannually. Multivariable logistic regression and general linear regression evaluated the association of Impella and IABP use with in-hospital outcomes. Overall, 12 035 hospitalizations with cardiogenic shock and VA-ECLS were identified, of which 3115 (26%) also received an IABP and 1880 (16%) an Impella. Use of an Impella with VA-ECLS substantially increased from 10% to 18% over this period (P<0.001), whereas an IABP modestly increased from 25% to 26% (P<0.001). In-hospital mortality decreased 54% to 48% for VA-ECLS only, 61% to 58% for VA-ECLS with an Impella, and 54% to 49% for VA-ECLS with an IABP (P<0.001 each). Most (57%) IABPs or Impellas were placed on the same day as VA-ECLS. After adjustment, there were no differences in in-hospital mortality or length of stay with the addition of an IABP or Impella compared with VA-ECLS alone. Conclusions From 2016 to 2018 in the United States, use of an Impella and IABP with VA-ECLS significantly increased. More than half of Impellas and IABPs were placed on the same day as VA-ECLS, and the use of a second mechanical circulatory support device did not impact in-hospital mortality. Further studies are needed to decipher the optimal timing and patient selection for this growing practice.

SKey Concepts Surrounding Cardiogenic Shock

Cardiogenic shock (CS) is the final common pathway of impaired cardiovascular performance that results in ineffective forward cardiac output producing clinical and biochemical signs of organ hypoperfusion. CS represents the most common cause of shock in the cardiac intensive care unit (CICU) and accounts for a substantial proportion of CICU patient deaths. Despite significant advances in revascularization techniques, pharmacologic therapeutics and mechanical support devices, CS remains associated with a high mortality rate. Indeed, the prevalence of CS within the CICU appears to be increasing. CS can be differentiated as phenotypes reflecting different metabolic, inflammatory, and hemodynamic profiles, depending also on anatomic substrate and congestion profile. Future prospective studies and clinical trials may further characterize these phenotypes and apply targeted intervention for each phenotype and SCAI SHOCK stage rather than a one-size-fits-all approach. Overall, there are 8 key concepts of CS; 1) the mortality associated with CS; 2) Shock attributed to AMI may be declining in both incidence and associated mortality; 3) providers should think about hemodynamic, metabolic, inflammation and cardiac function in totality to assess CS; 4) CS is a dynamic process; 5) no randomized trials evaluating use of the PAC in patients with CS; 6) most data supporting neosynephrine as first line agent in CS; 7) most registries suggest that almost half of CS patients do not have any mechanical support, and the vast majority of the remainder utilize the IABP; and 8) patients with AMI CS should receive emergent PCI of the culprit vessel.

A Comprehensive Appraisal of Risk Prediction Models for Cardiogenic Shock

ABSTRACT

Despite advances in early revascularization, percutaneous hemodynamic support platforms, and systems of care, cardiogenic shock (CS) remains associated with a mortality rate higher than 50%. Several risk stratification models have been derived since the 1990 s to identify patients at high risk of adverse outcomes. Still, limited information is available on the differences between scoring systems and their relative applicability to both acute myocardial infarction and advanced decompensated heart failure CS. Thus, we reviewed the similarities, differences, and limitations of published CS risk prediction models and herein discuss their suitability to the contemporary management of CS care.

Hemodynamic-based Assessment and Management of Cardiogenic Shock

Cardiogenic shock (CS) remains a deadly disease entity challenging patients, caregivers, and communities across the globe. CS can rapidly lead to the development of hypoperfusion and end-organ dysfunction, transforming a predictable hemodynamic event into a potential high-resource, intense, hemometabolic clinical catastrophe. Based on the scalable heterogeneity from a cellular level to healthcare systems in the hemodynamic-based management of patients experiencing CS, we present considerations towards systematic hemodynamic-based transitions in which distinct clinical entities share the common path of early identification and rapid transitions through an adaptive longitudinal situational awareness model of care that influences specific management considerations. Future studies are needed to best understand optimal management of drugs and devices along with engagement of health systems of care for patients with CS.

Platelet Phenotype and Function Changes With Increasing Duration of Extracorporeal Membrane Oxygenation

OBJECTIVES

To investigate platelet pathophysiology associated with pediatric extracorporeal membrane oxygenation (ECMO).

DESIGN

Prospective observational study of neonatal and pediatric ECMO patients from September 1, 2016, to December 31, 2019.

SETTING

The PICU in a large tertiary referral pediatric ECMO center.

PATIENTS

Eighty-seven neonates and children (< 18 yr) supported by ECMO.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Arterial blood samples were collected on days 1, 2, and 5 of ECMO and were analyzed by whole blood flow cytometry. Corresponding clinical data for each patient was also recorded. A total of 87 patients were recruited (median age, 65 d; interquartile range [IQR], 7 d to 4 yr). The median duration of ECMO was 5 days (IQR, 3-8 d) with a median length of stay in PICU and hospital of 18 days (IQR, 10-29 d) and 35 days (IQR, 19-75 d), respectively. Forty-two patients (48%) had at least one major bleed according to a priori determined definitions, and 12 patients (14%) had at least one thrombotic event during ECMO. Platelet fibrinogen receptor expression decreased (median fluorescence intensity [MFI], 29,256 vs 26,544; p = 0.0005), while von Willebrand Factor expression increased (MFI: 7,620 vs 8,829; p = 0.0459) from day 2 to day 5 of ECMO. Platelet response to agonist, Thrombin Receptor Activator Peptide 6, also decreased from day 2 to day 5 of ECMO, as measured by binding with anti-P-selectin, PAC-1 (binds activated GPIIb/IIIa), and anti-CD63 monoclonal antibodies (P-selectin area under the curve [AUC]: 63.46 vs 42.82, respectively, p = 0.0022; PAC-1 AUC: 93.75 vs 74.46, p = 0.0191; CD63 AUC: 55.69 vs 41.76, p = 0.0020).

CONCLUSIONS

The loss of platelet response over time may contribute to bleeding during ECMO. These novel insights may be useful in understanding mechanisms of bleeding in pediatric ECMO and monitoring platelet markers clinically could allow for prediction or early detection of bleeding and thrombosis.

Risk factors associated with in-hospital mortality for patients with ECLS due to post cardiotomy cardiogenic shock after isolated coronary surgery

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) or extracorporeal life support (ECLS) in patients after cardiac surgery and post cardiotomy cardiogenic shock (PCS) is known to be associated with high mortality. Especially in patients after coronary artery bypass grafting (CABG) and PCS, ECLS is frequently established. Aim of this analysis was to evaluate factors associated with in-hospital mortality in patients treated with ECLS due to PCS after CABG.

METHODS

Between August 2006 and January 2017, 92 consecutive patients with V-A ECLS due to PCS after isolated CABG were identified and included in this retrospective analysis. Patients were divided into survivors (S) and non-survivors (NS) and analysed in regard of risk factors of in-hospital mortality.

RESULTS

In-hospital mortality added up to 61 patients (66 %). Non-survivors were significantly older (60±12 (S) vs. 67±10 (NS); p=0.013). Bilateral internal mammary artery graft was significantly more frequently used in S (23% (S) vs. 2% (NS); p=0.001). After 24 hours of ECLS support, median lactate levels were significantly higher in NS (1.9(1.3;3.5) mmol/L (S) vs. 3.5(2.1;6.3) mmol/L (NS); p=0.001). NS suffered more often acute kidney injury requiring dialysis (42% (S) vs. 74% (NS); p=0.002).

CONCLUSION

Mortality in patients with refractory PCS after CABG and consecutive ECLS support remains high. Failing end-organ recovery under ECLS despite optimized concomitant medical therapy is an indicator of adverse outcomes in this specific patient cohort. Moreover, total-arterial revascularization might be beneficial for cardiac recovery in patients suffering PCS after CABG and following ECLS.

Hospital Costs of Extracorporeal Membrane Oxygenation in Adults: A Systematic Review

BACKGROUND

Costs associated with extracorporeal membrane oxygenation (ECMO) are an important factor in establishing cost effectiveness. In this systematic review, we aimed to determine the total hospital costs of ECMO for adults.

METHODS

The literature was retrieved from the PubMed/MEDLINE, EMBASE, and Web of Science databases from inception to 4 March 2020 using the search terms 'extracorporeal membrane oxygenation' combined with 'costs'; similar terms or phrases were then added to the search, i.e. 'Extracorporeal Life Support' or 'ECMO' or 'ECLS' combined with 'costs'. We included any type of study (e.g. randomized trial or observational cohort) evaluating hospital costs of ECMO in adults (age ≥18 years).

RESULTS

A total of 1768 unique articles were retrieved during our search. We assessed 74 full-text articles for eligibility, of which 14 articles were selected for inclusion in this review; six papers were from the US, five were from Europe, and one each from Japan, Australia, and Taiwan. The sample sizes ranged from 16 to 18,684 patients. One paper exclusively used prospective cost data collection, while all other papers used retrospective data collection. Five papers reported charges instead of costs. There was large variation in hospital costs, ranging from US$22,305 to US$334,608 (2019 values), largely depending on the indication for ECMO support and location. The highest reported costs were for lung transplant recipients who were receiving ECMO support in the US, and the lowest reported costs were for extracorporeal cardiopulmonary resuscitation patients presenting with non-shockable rhythm in Japan. The additional costs of ECMO patients compared with non-ECMO patients varied between US$2518 and US$200,658. Personnel costs varied between 11 and 52% of the total amount.

CONCLUSIONS

ECMO therapy is an advanced and expensive technology, although reported costs differ considerably depending on ECMO indication and whether charges or costs are measured. Combined with the ongoing gathering of outcome data, cost effectiveness per ECMO indication could be determined in the future.

Short-term mechanical circulatory support in elderly patients

BACKGROUND

Age over 70 years seems to confer poor prognosis for patients under mechanical circulatory support (MCS). Advanced age is usually a relative contraindication. Our objective was to assess the impact of age on survival of patients with short-term MCS.

METHODS

Retrospective analysis of ≥70-year-old patients supported with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) or Impella CP® due to cardiogenic shock and other situations of hemodynamic instability in a referral hospital (elderly group), compared with younger patients (<70 years). We analyze factors associated with survival in elderly group.

RESULTS

Out of 164 short-term MCS implants from 2013 to October 2020, 45 (27.4%) correspond to ≥70-year-old patients (73.3% VA-ECMO; 26.7% Impella CP®), 80% as bridge to recovery and 15.6% for high-risk percutaneous coronary intervention (PCI). We found no significant differences in complications developed between both groups. Survivals at discharge (40% vs. 43.7%, p = 0.403) and at follow-up (median 13.6 [30] months) were similar in elderly and young patients (35.6% vs. 37.8%, log-rank p = 0.061). Predictive factors of mortality in elderly patients were peripheral artery disease (p = 0.037), higher lactate (p = 0.003) and creatinine (p = 0.035) at implant, longer cardiac arrest (p = 0.003), and worse post-implantation left ventricular ejection fraction (p = 0.003). Patients with indication of MCS for high-risk PCI had higher survival compared to other indications (p = 0.013).

CONCLUSION

Short-term MCS with VA-ECMO or Impella CP® in elderly patients may be a reasonable option in hemodynamic compromise situations as bridge to recovery or elective high-risk PCI, without a significant increase in complications or mortality. Age should not be an absolute contraindication, but careful selection of candidate patients is necessary.

Effect of Acute Limb Ischemia on the Mortality of Patients with Extracorporeal Membrane Oxygenation Established by Femoral Vein-Arterial Catheterization and Analysis of Related Risk Factors

Extracorporeal membrane oxygenation (ECMO) is a common treatment for cardiopulmonary failure. Although it can effectively reduce the mortality of patients with cardiopulmonary failure, it still has a high mortality rate, such as acute limb ischemia (ALI), stroke, liver and kidney failure, and other related complications and related causes of death. This study aims to explore the impact of ALI on the mortality of VA-ECMO patients in hospital and 6 months after discharge and analyze the occurrence of ALI and related factors that affect the mortality of VA-ECMO in hospital and 6 months after discharge. The results showed that the smoking history was an independent risk factor for ALI, and age, diabetes, cardiac arrest, first time of ECMO, and hyperbilirubinemia were associated risk factors for in-hospital mortality. Cardiac arrest and ALI were associated risk factors for mortality at 6 months after discharge. Although ALI is not significantly associated with VA-ECMO in-hospital mortality, it is a risk factor for mortality at 6 months after discharge, and medical personnel should therefore strive to reduce and avoid ALI.

Association of Hospital Safety Net Status With Outcomes and Resource Use for Extracorporeal Membrane Oxygenation in the United States

PURPOSE

Safety net hospitals (SNH) have been associated with inferior surgical outcomes and increased resource use. Utilization and outcomes for extracorporeal membrane oxygenation (ECMO), a rescue modality for patients with respiratory or cardiac failure, may vary by safety net status. We hypothesized SNH to be associated with inferior outcomes and costs of ECMO in a national cohort.

MATERIALS AND METHODS

The 2008-2017 National Inpatient Sample was queried for ECMO hospitalizations and safety net hospitals were identified. Multivariable regression was used to perform risk-adjusted comparisons of mortality, complications and resource utilization at safety net and non-safety net hospitals.

RESULTS

Of 36,491 ECMO hospitalizations, 28.2% were at SNH. On adjusted comparison SNH was associated with increased odds of mortality (AOR: 1.23), tracheostomy use (AOR: 1.51), intracranial hemorrhage (AOR: 1.39), as well as infectious complications (AOR: 1.21, all P < .05), with NSNH as reference. SNH was also associated with increased hospitalization duration (β=+4.5 days) and hospitalization costs (β=+$32,880, all P < .01).

CONCLUSIONS

We have found SNH to be associated with inferior survival, increased complications, and higher costs compared to NSNH. These disparate outcomes warrant further studies examining systemic and hospital-level factors that may impact outcomes and resource use of ECMO at SNH.

Risk Scores in ST-Segment Elevation Myocardial Infarction Patients with Refractory Cardiogenic Shock and Veno-Arterial Extracorporeal Membrane Oxygenation

Although many risk models have been tested in patients implanted by veno-arterial extracorporeal membrane oxygenation (VA-ECMO), few scores assessed patients’ prognosis in the setting of ST-segment elevation myocardial infarction (STEMI) with refractory cardiogenic shock. We aimed at assessing the performance of risk scores, notably the prEdictioN of Cardiogenic shock OUtcome foR AMI patients salvaGed by VA-ECMO (ENCOURAGE) score, for predicting mortality in this particular population. This retrospective observational study included patients admitted to Tours University Hospital for STEMI with cardiogenic shock and requiring hemodynamic support by VA-ECMO. Among the fifty-one patients, the 30-day and 6-month survival rates were 63% and 56% respectively. Thirty days after VA-ECMO therapy, probabilities of mortality were 12, 17, 33, 66, 80% according to the ENCOURAGE score classes 0–12, 13–18, 19–22, 23–27, and ≥28, respectively. The ENCOURAGE score (AUC of the Receiving Operating Characteristic curve = 0.83) was significantly better compared to other risk scores. The hazard ratio for survival at 30 days for each point of the ENCOURAGE score was 1.10 (CI 95% (1.06, 1.15); p < 0.001). Decision curve analysis indicated that the ENCOURAGE score had the best clinical usefulness of the tested risk scores and the Hosmer–Lemeshow test suggested an accurate calibration. Our data suggest that the ENCOURAGE score is valid and the most relevant score to predict 30-day mortality after VA-ECMO therapy in STEMI patients with refractory cardiogenic shock. It may help decision-making teams to better select STEMI patients with shock for VA-ECMO therapy.

Cannulation Strategy for Extracorporeal Membrane Oxygenation Does Not Influence Total Hospital Cost

BACKGROUND

Center for Medicare Services decreased reimbursement rates for peripheral veno-arterial (VA ECMO) and veno-venous (VV ECMO) extracorporeal membrane oxygenation procedures in October 2018. Limited data are available describing hospital costs and clinical resources required to support ECMO patients.

METHODS

All patients supported on ECMO at our institution between March 2017 and October 2018 were identified. Exclusion criteria were cannulation at referring hospitals, organ transplant recipients, and temporary right ventricular support. The cohort was stratified by initial cannulation strategy. Outcomes were total hospital cost and clinical resource utilization.

RESULTS

29 patients were supported on central VA, 72 on peripheral VA, and 37 on VV ECMO. Thirty-day survival was 48% for central vs 37% for peripheral vs 51% for VV. Hospital costs were $187,848 for central vs $178,069 for peripheral vs $172,994 for VV, P=0.91. Mean hospital stay was 25.8 days for central vs 21.5 for peripheral vs 26.2 for VV, P=0.49. Mean intensive care unit stay was 14.1 days for central vs 12.8 for peripheral vs 7.7 for VV, P=0.25. Mean length of ECMO support was 6.5 days for central vs 6.2 for peripheral vs 7.8 for VV, P=0.38. Mean ventilator time was 13.0 days for central vs 8.2 for peripheral vs 10.0 for VV P=0.06. Hemodialysis was utilized in 41% central, 47% peripheral, and 41% VV patients, P=0.75. Theoretical ECMO reimbursement losses ranged from $1,970,698 to $5,648,219 annually under 2018 Center for Medicare Services rates.

CONCLUSIONS

ECMO cannulation strategy has minimal impact on resource utilization and hospital cost.

The Year in Cardiothoracic Critical Care: Selected Highlights from 2019

In 2019, cardiothoracic and vascular critical care remained an important focus and subspecialty. This article continues the annual series to review relevant contributions in postoperative critical care that may affect the cardiac anesthesiologist. Herein, the pertinent literature published in 2019 is explored and organized by organ system.

Transition to Advanced Therapies in Elderly Patients Supported by Extracorporeal Membrane Oxygenation Therapy

BACKGROUND

Although the use of extracorporeal membrane oxygenation (ECMO) continues to increase, very little is known about how age influences the transition to definitive advanced therapies.

METHODS

Using the National Inpatient Sample database from 2008 to 2017, we analyzed patients supported by ECMO for cardiogenic shock and separated patients into 2 age cohorts: < 65 years and ≥ 65 years. Primary outcomes of interest included the proportion of patients undergoing orthotopic cardiac transplantation (OHT) and left ventricular assist device (LVAD) implantation.

RESULTS

Over the study period, we identified 16,132 hospitalizations of people with cardiogenic shock requiring ECMO support. Significantly fewer patients in the older group underwent OHT compared to the younger group (0.4% vs 1.2%, P < 0.001). Compared to the younger group, a lower proportion of those ≥ 65 years received an LVAD (3.7% vs 5.8%, P < 0.001). LVAD implantation increased over the study period in both age cohorts, whereas OHT increased only in the < 65 group (P < 0.05, all). After multivariable adjustment, patients in the oldest age group were still less likely to receive an LVAD (odds ratio 0.54; confidence interval: 0.43-0.69, P < 0.001) and continued to have the highest odds of in-hospital mortality (odds ratio 1.53; confidence interval : 1.39-1.69, P < 0.001).

CONCLUSIONS

Survival of patients ≥ 65 years requiring ECMO for cardiogenic shock is poor and less commonly includes transition to definitive advanced therapies. Although we must stress that no patient should be denied ECMO based solely on age, we believe our results may be helpful for providers when counseling patients and their families.

Predicting Survival After Extracorporeal Membrane Oxygenation by Using Machine Learning

BACKGROUND

Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) undoubtedly saves many lives, but it is associated with a high degree of patient morbidity, mortality, and resource use. This study aimed to develop a machine learning algorithm to augment clinical decision making related to VA-ECMO.

METHODS

Patients supported by VA-ECMO at a single institution from May 2011 to October 2018 were retrospectively reviewed. Laboratory values from only the initial 48 hours of VA-ECMO support were used. Data were split into 70% for training, 15% for validation, and 15% withheld for testing. Feature importance was estimated, and dimensionality reduction techniques were used. A deep neural network was trained to predict survival to discharge, and the final model was assessed using the independent testing cohort. Model performance was compared with that of the SAVE (Survival After Veno-arterial ECMO) score by using a receiver operator characteristic curve.

RESULTS

Of the 282 eligible adult patients who were undergoing VA-ECMO, 117 (41%) survived to discharge. A total of 1.96 million laboratory values were extracted from the electronic medical record, from which 270 different summary variables were derived for each patient. The most important variables in predicting the primary outcome included lactate, age, total bilirubin, and creatinine. For the testing cohort, the final model achieved 82% overall accuracy and a greater area under the curve than the SAVE score (0.92 vs 0.65; P = .01) in predicting survival to discharge.

CONCLUSIONS

This proof of concept study demonstrates the potential for machine learning models to augment clinical decision making for patients undergoing VA-ECMO. Further development with multi-institutional data is warranted.

Noteworthy Literature From 2019 for Cardiothoracic Critical Care

This annual article summarizes key findings from notable studies published in 2019 relevant to the practice of cardiothoracic critical care medicine. This year's article encompasses updates to the literature on enhanced recovery after cardiac surgery, extracorporeal membranous oxygenation, delirium, and primary graft dysfunction after heart transplant.

Cost-utility of venoarterial extracorporeal membrane oxygenation in cardiogenic shock and cardiac arrest

BACKGROUND

The use of venoarterial extracorporeal membrane oxygenation in cardiogenic shock keeps increasing, but its cost-utility is unknown.

METHODS

We studied retrospectively the cost-utility of venoarterial extracorporeal membrane oxygenation in a five-year cohort of consequent patients treated due to refractory cardiogenic shock or cardiac arrest in a transplant centre in 2013-2017. In our centre, venoarterial extracorporeal membrane oxygenation is considered for all cardiogenic shock patients potentially eligible for heart transplantation, and for selected postcardiotomy patients. We assessed the costs of the index hospitalization and of the one-year hospital costs, and the patients' health-related quality of life (response rate 71.7%). Based on the data and the population-based life expectancies, we calculated the amount and the costs of quality-adjusted life years gained both without discount and with an annual discount of 3.5%.

RESULTS

The cohort included 102 patients (78 cardiogenic shock; 24 cardiac arrest) of whom 67 (65.7%) survived to discharge and 66 (64.7%) to one year. The effective costs per one hospital survivor were 242,303€. Median in-hospital costs of the index hospitalization per patient were 129,967€ (interquartile range 150,340€). Mean predicted number of quality-adjusted life years gained by the treatment was 20.9 (standard deviation 9.7) without discount, and the median cost per quality-adjusted life year was 7474€ (interquartile range 10,973€). With the annual discount of 3.5%, 13.0 (standard deviation 4.8) quality-adjusted life years were gained with the cost of 12,642€ per quality-adjusted life year (interquartile range 15,059€).

CONCLUSIONS

We found the use of venoarterial extracorporeal membrane oxygenation in refractory cardiogenic shock and cardiac arrest justified from the cost-utility point of view in a transplant centre setting.

Early prediction of transition to durable mechanical circulatory support in patients undergoing peripheral veno-arterial extracorporeal membrane oxygenation for critical cardiogenic shock

Peripheral veno-arterial extracorporeal membrane oxygenation (pVA-ECMO) has gained increasing value in the management of patients with critical cardiogenic shock (cCS), allowing time for myocardial recovery. Failure of myocardial recovery has life-altering consequences: transition to durable mechanical circulatory support (dMCS), urgent heart transplantation, or withdrawal of support. Clinical factors controlling myocardial recovery under these circumstances remain largely unknown. Using a retrospective cohort, we developed a model for early prediction of transition to dMCS in patients undergoing pVA-ECMO for cCS. To promote myocardial recovery, our clinical management centered around left ventricular pressure unloading, that is, targeting pulmonary capillary wedge pressures (PCWP) ≤18 mm Hg. We collected demographic data, laboratory findings, inotrope use, and two-dimensional transthoracic echocardiography measurements, all limited to the first 72h of pVA-ECMO (D1-3). Out of 70 patients who were alive after pVA-ECMO, 27 patients underwent implantation of dMCS. There was no significant difference in survival to hospital discharge between patients with or without transition to dMCS. Ejection fraction_D1-3 (per 10% increase, OR 0.37 [0.17-0.79]) and amount of inotropic support_D1-3 (OR 4.77 [1.6-14.18]) but neither myocardial wall tension nor PCWP emerged as significant predictors of transition to dMCS. Optimism-corrected c-index (0.90 [0.89-0.90]) revealed an excellent discriminative ability of our model. In summary, our model for early prediction of transition to dMCS in patients with cCS undergoing pVA-ECMO identifies indicators of inotropic state as relevant factors. Absence of markers for myocardial oxygen consumption or left ventricular pressure loading allows us to hypothesize sufficient cardiac unloading in our cohort with PCWP-targeted management.