Experience with percutaneous venoarterial cardiopulmonary bypass for emergency circulatory support

Time to initiation of extracorporeal membrane oxygenation in conventional cardiopulmonary resuscitation affects the patient survival prognosis

BACKGROUND

Cardiopulmonary resuscitation (CPR) is the cornerstone intervention for cardiac arrest, with extracorporeal CPR (ECPR) demonstrating enhanced survival and neurologic outcomes in in-hospital cardiac arrest. This study explores the time interval between CPR initiation and the onset of extracorporeal membrane oxygenation (ECMO) in ECPR recipients, investigating its impact on survival outcomes.

METHODS

This retrospective analysis included 1950 adults who received CPR at a single medical center between March 2019 and April 2023. Data from 198 adult patients who had ECMO inserted during CPR were analyzed. The interval from CPR initiation to ECMO initiation was quantified and categorized as ≤20, 20-40, and >40 min. Cox regression analysis assessed associations between CPR-to-ECMO time and short- and long-term mortalities.

RESULTS

Among the 198 patients who underwent ECPR, 116 (58.6%) experienced 30-day mortality. Initiation of ECMO within 20 min occurred in 46 (23.2%), whereas 74 (37.4%) had ECMO initiated after 40 min. Cox regression revealed a significant association between time from CPR to ECMO initiation and 30-day mortality (adjusted hazard ratio [HR]: 2.20 in >40 min, HR: 2.63 in 20-40 min, p = 0.006) and 6-month mortality (HR: 1.81, in >40 min, HR: 1.99 in 20-40 min, p = 0.021).

CONCLUSIONS

This study revealed that, in ECPR recipients, a shorter duration between CPR initiation and ECMO flow commencement is associated with improved short- and long-term patient prognoses. These findings emphasize the critical role of timely ECMO application in optimizing outcomes for patients undergoing ECPR.

Central extracorporeal membrane oxygenation with left-ventricular vent for fulminant myocarditis: a retrospective study

PURPOSE

Fulminant myocarditis presents as acute severe heart failure and requires mechanical cardiocirculatory support. Left-ventricular (LV) decompression is necessary for the successful recovery of these patients. This retrospective study aimed to evaluate the functional outcomes of providing central extracorporeal membrane oxygenation (ECMO) with LV decompression for the treatment of refractory fulminant myocarditis.

METHODS

Between January 2015 and February 2021, seven consecutive fulminant myocarditis patients (mean age: 41.1 ± 26.1 years) received central ECMO support with transapical LV decompression, with an 18 French cannula integrated into the ECMO circuit in a Y-fashion. The baseline characteristics and postoperative outcomes of the patients were collected.

RESULTS

On admission, all patients received prior peripheral ECMO, and 85.7% (6/7) of patients received prior intra-aortic balloon pumping. However, all patients had refractory cardiogenic shock that failed prior to decompression. Six patients recovered successfully after a mean ECMO support of 20.0 ± 11.5 days and five patients had no recurrence of cardiac decompensation. The mean ICU and mean hospital stays were 36.7 ± 23.5 days and 60.6 ± 24.9 days, respectively. Hospital mortality was 28.6% (2/7). Two patients died due to sepsis and stroke during hospitalization.

CONCLUSIONS

Central ECMO with an LV vent was effective for fulminant myocarditis refractory to percutaneous cardiopulmonary support therapy and other therapies.

Rapid Development and Deployment of an Intensivist-Led Venovenous Extracorporeal Membrane Oxygenation Cannulation Program

OBJECTIVES

To determine the safety and efficacy of a rapidly deployed intensivist-led venovenous extracorporeal membrane oxygenation cannulation program in a preexisting extracorporeal membrane oxygenation program.

DESIGN

A retrospective observational before-and-after study of 40 patients undergoing percutaneous cannulation for venovenous extracorporeal membrane oxygenation in an established cannulation program by cardiothoracic surgeons versus a rapidly deployed medical intensivist cannulation program.

SETTING

An adult ICU in a tertiary academic medical center in Camden, NJ.

PATIENTS

Critically ill adult subjects with severe respiratory failure undergoing percutaneous cannulation for venovenous extracorporeal membrane oxygenation.

INTERVENTIONS

Percutaneous cannulation for venovenous extracorporeal membrane oxygenation performed by cardiothoracic surgeons compared with cannulations performed by medical intensivists.

MEASUREMENTS AND MAIN RESULTS

Venovenous extracorporeal membrane oxygenation cannulation site attempts were retrospectively reviewed. Subject demographics, specialty of physician performing cannulation, type of support, cannulation configuration, cannula size, imaging guidance, success rate, and complications were recorded and summarized. Twenty-two cannulations were performed by three cardiothoracic surgeons in 11 subjects between September 2019 and February 2020. The cannulation program rapidly transitioned to an intensivist-led and performed program in March 2020. Fifty-seven cannulations were performed by eight intensivists in 29 subjects between March 2020 and December 2020. Mean body mass index for subjects did not differ between groups (33.86 vs 35.89; p = 0.775). There was no difference in days on mechanical ventilation prior to cannulation, configuration, cannula size, or discharge condition. There was no difference in success rate of cannulation on first attempt per cannulation site (95.5 vs 96.7; p = 0.483) or major complication rate per cannulation site (4.5 vs 3.5; p = 1).

CONCLUSIONS

There is no difference between success and complication rates of percutaneous venovenous extracorporeal membrane oxygenation canulation when performed by cardiothoracic surgeons versus medical intensivist in an already established extracorporeal membrane oxygenation program. A rapidly deployed cannulation program by intensivists for venovenous extracorporeal membrane oxygenation can be performed with high success and low complication rates.

Incidence of Acute Kidney Injury Is Lower in High-Risk Patients Undergoing Percutaneous Coronary Intervention Supported with Impella Compared to ECMO

Acute kidney injury (AKI) is a common complication post-PCI. Here, in a single-center observational registry, we compared the frequency of AKI in patients at elevated risk for AKI (based on Mehran risk stratification scoring) who underwent VA-ECMO- or Impella-supported high-risk PCI. A total of 28 patients scheduled for elective high-risk PCI with mechanical circulatory support were studied prospectively. All patients were turned down for surgery due to exceedingly high risk. Allocation to VA-ECMO (n=11) or Impella (n=17) was performed according to site-specific restrictions on the daily availability of the VA-ECMO platform as a prospective enrollment and performed prior to initiation of PCI. We analyzed AKI incidence as our primary endpoint, as well as PCI success, duration, and peripheral complications. All patients were successfully revascularized and had MCS weaned at the end of the procedure. Baseline GFR and procedural contrast media were similar. Despite similar risks for AKI as calculated by the Mehran score (35 ± 18.9 vs. 31 ± 16.6 %; p=0.55), patients supported by Impella during PCI demonstrated a reduced incidence of AKI (55 vs. 12 %; p=0.03). MCS-assisted high-risk PCI with VA-ECMO or Impella is feasible. However, Impella is associated with a shorter procedure time and a lower incidence of AKI.

ECPella: Concept, Physiology and Clinical Applications

Addition of Impella on top of venoarterial extracorporeal membrane oxygenation (VA-ECMO) has gained wide interest as it might portend improved outcomes in patients with cardiogenic shock. This has been consistently reported in retrospective propensity-matched studies, case series, and meta-analyses. The pathophysiologic background is based on the mitigation of ECMO-related side effects and the additive benefit of myocardial unloading. In this perspective, thorough knowledge of these mechanisms is required to optimize the management of mechanical circulatory support with this approach and introduce best practices, as the interplay between the two devices and the implantation-explantation strategies are key for success.

Currently Available Options for Mechanical Circulatory Support for the Management of Cardiogenic Shock

Cardiogenic shock (CS) is a complex condition with a high risk for morbidity and mortality. Mechanical circulatory support (MCS) devices were developed to support patients with CS in cases refractory to treatment with vasoactive medications. Current devices include intra-aortic balloon pumps, intravascular microaxial pumps, percutaneous LVAD, percutaneous RVAD, and VA ECMO. Data from limited observational studies and clinical trials show a clear difference in the level of hemodynamic support offered by each device. However, at this point, there are insufficient clinical trial data to guide MCS selection and, until ongoing clinical trials are completed, use of the right device for the right patient depends largely on clinical judgment.

A case report of thrombotic complete obstruction of the ascending aorta as a complication of Venoarterial extracorporeal membrane oxygenation support: steps to prevent thrombosis

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is an essential device in the field of emergency and intensive-care medicine. However, long-term use of VA-ECMO has various severe complications, including thrombosis.

CASE PRESENTATION

A 60-year-old man underwent his third aortic root replacement using a homograft because of infectious endocarditis. Although the operation was difficult because of severe adhesion caused by the two previous interventions, aortic root replacement using a homograft was performed. At the time of withdrawal from cardiopulmonary bypass, the maintenance of hemodynamics was difficult because of bleeding from the surgical site, leading to hypovolemic shock. Cardiac function subsequently deteriorated; therefore, VA-ECMO was established and the operation was finished. Three days later, thrombus was formed inside the homograft and completely occluded ascending aorta. Evacuation of hematoma was performed, however, cardiac function was not ameliorated. Eventually, the patient had brain infarction and died. To prevent thrombus formation in very severe low cardiac output cases under VA-ECMO management after surgery, to prevent the stagnation of the blood flow from VA-ECMO will be necessary because anticoagulant therapy will be difficult. Impella ventricular assist device which is recently used widely generates anterograde blood flow and effectively prevents stagnation.

CONCLUSIONS

To prevent thrombus formation in cases of very severe low cardiac output, Impella® should be combinatorially introduced from the beginning of VA-ECMO establishment to prevent thrombosis.

Predictors of in-hospital mortality and midterm outcomes of patients successfully weaned from venoarterial extracorporeal membrane oxygenation

OBJECTIVES

There is limited evidence to guide the decision to proceed with weaning from venoarterial extracorporeal membrane oxygenation, and approximately 30% of patients weaned "successfully" do not survive to hospital discharge. We evaluated predictors of in-hospital mortality and midterm outcomes of patients successfully weaned from venoarterial extracorporeal membrane oxygenation after support for cardiogenic shock, surviving more than 24 hours after weaning, with the aim of improving patient selection for durable weaning.

METHODS

We performed a retrospective analysis of 92 patients supported on venoarterial extracorporeal membrane oxygenation and successfully weaned between January 2013 and February 2018. Survival was estimated by the Kaplan-Meier method. Predictors of in-hospital mortality were identified using a Cox proportional hazards model and an Akaike information criterion-selected multivariate model.

RESULTS

Overall survival at hospital discharge was 64.2%; survival was 54.6% 1 year after support and 51.4% 3 years after support. A history of diabetes, previous myocardial infarction, prolonged extracorporeal membrane oxygenation support, and hypoxemia at extracorporeal membrane oxygenation weaning were independent predictors of in-hospital mortality. At midterm follow-up, New York Heart Association class I heart function was observed in 53% of patients, class II in 19%, class III in 16%, and class IV in 12%. Average left ventricular ejection fraction was 46.5% ± 18.2%, and 50% of the patients had been readmitted to the hospital because of heart failure.

CONCLUSIONS

Durable extracorporeal membrane oxygenation weaning with acceptable midterm functional status is obtainable in well-selected patients. Previous myocardial infarction, diabetes, prolonged extracorporeal membrane oxygenation support, and pulmonary dysfunction strongly predicted in-hospital mortality after venoarterial extracorporeal membrane oxygenation weaning. In this high-risk situation, other heart replacement therapies should be considered.

Left ventricular decompression on Veno-arterial extracorporeal membrane oxygenation with intra-aortic balloon Counterpulsation

Background

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been used increasingly to support patients with cardiogenic shock (CS). There has been growing recognition of the favorable and unfavorable hemodynamic effects of this therapy and recent interest in the use of other percutaneous circulatory support devices to offset some of the potentially harmful hemodynamic effects. Herein, we provide visual evidence of the effects of intra-aortic balloon pump (IABP) counterpulsation for a patient with peripheral VA-ECMO cannulation.

Case presentation

A 68 year old man who had undergone orthotopic heart transplantation presented with 2 days of fatigue, orthopnea, and paroxysmal nocturnal dyspnea. On examination, he was tachycardic, hypotensive and hypoxic with cool extremities, consistent with CS. Transthoracic echocardiogram (TTE) showed new severe biventricular dysfunction with a left ventricular ejection fraction of 15%, right heart catheterization demonstrated elevated filling pressures and low output. An IABP was inserted via the left femoral artery with minimal improvement in hemodynamics. He was escalated to VA-ECMO. Repeat TTE demonstrated aortic valve (AV) opening with each cardiac cycle and mild MR. With placement of the IABP on standby Additional file 1: Video 1 (video 0:03), the AV no longer opened. Re-initiation of balloon counterpulsation resulted in resumed AV opening with each beat Additional file 1: Video 1 (video 0:17). He was treated for presumed acute allograft rejection with methylprednisolone, thymoglobulin, intravenous immunoglobulin and plasmapheresis with improvement in allograft function. However, he developed an Enterobacter aerogenes pneumonia and rapidly fatal septic shock.

Conclusions

This case visually demonstrates effective LV decompression by IABP counterpulsation in VA-ECMO support. While the overall effects of LV decompression in patients on VA-ECMO with IABP are still unclear, this report demonstrates one potential mechanism of benefit in the prevention of stagnation of blood flow that may lead to intra-cardiac or aortic root thrombus formation.

Electronic supplementary material

The online version of this article (10.1186/s13019-019-0970-3) contains supplementary material, which is available to authorized users.

The top 100 manuscripts in emergency cardiac surgery. Potential role in cardiothoracic training. A bibliometric analysis

Background

Emergency Cardiac Surgery (ECS) is a component of cardiothoracic training. Citations are considered to represent a papers influence. Bibliometric analyses allow us to identify the most influential work, and future research. We aim to highlight the key research themes within ECS and determine their potential impact on cardiothoracic training.

Methods

Thomas Reuters Web of Science was searched using terms [Emergency AND Card* AND Surg*]. Results were ranked by citation and reviewed by a panel of cardiac surgeons to identify the top 100 cited papers relevant to ECS. Papers were analysed by topic, journal and impact. Regression analysis was used to determine a link between impact factor and scientific impact.

Results

3823 papers were identified. Median citations for the top 100 was 88. The paper with the highest impact was by Nashef et al. focusing on the use of EuroSCORE (2043 citations). The Annals of Thoracic Surgery published most papers (n = 18:1778 citations). The European Journal of Cardiothoracic Surgery coveted the most citations (n = 2649). The USA published most papers (n = 55).The most ubiquitous topics were; risk stratification, circulatory support and aortic surgery. A positive relationship between journal impact fact and the scientific impact of manuscripts in ECS (P = 0.043) was deduced.

Conclusion

This study is the first of its kind and identified the papers which are likely to the contribute most to training and understanding of ECS. A papers influence is partially determined by journal impact factor. Bibliometric analysis is a potent tool to identify surgical training needs.

Successful Use of ECMO in Adults with Life-threatening Infections

Two cases of critically ill patients who received extracorporeal membrane oxygenation (ECMO) using different forms of circuitry and for different indications are presented. Both patients had life-threatening infections with septic shock and were not able to be supported by conventional means. The first patient had staphylococcal septicaemia and received venoarterial ECMO for circulatory failure. The second patient had psittacosis and received venovenous ECMO for respiratory failure. We discuss the expanding indications for this technology and the role it has to play in adult intensive care.

Investigation of microcirculation in patients with venoarterial extracorporeal membrane oxygenation life support

Background

Microcirculatory dysfunction develops in both septic and cardiogenic shock patients, and it is associated with poor prognosis in patients with septic shock. Information on the association between microcirculatory dysfunction and prognosis in cardiogenic shock patients with venoarterial extracorporeal membrane oxygenation (VA-ECMO) support is limited.

Methods

Sublingual microcirculation images were recorded using an incident dark-field video microscope at the following time points: within 12 h (T1), 24 h (T2), 48 h (T3), 72 h (T4), and 96 h (T5) after VA-ECMO placement. If a patient could be weaned off VA-ECMO, sublingual microcirculation images were recorded before and after VA-ECMO removal. Microcirculatory parameters were compared between 28-day nonsurvivors and survivors with VA-ECMO support. In addition, the microcirculation and clinical parameters were assessed as prognostic tests of 28-day mortality, and patients were divided into three subgroups according to microcirculation parameters for survival analysis.

Results

Forty-eight patients were enrolled in this study. At T1, the observed heart rate, mean arterial pressure, inotropic score and lactate level of 28-day nonsurvivors and survivors did not differ significantly, but the perfused small vessel density (PSVD) and proportion of perfused vessels (PPV) were lower in the 28-day nonsurvivors than in the survivors. The PSVD and PPV were slightly superior to lactate levels in predicting 28-day mortality (area under curve of 0.68, 0.70, and 0.62, respectively). The subgroup with the lowest PSVD (< 15 mm/mm²) and PPV (< 64%) values exhibited less favorable survival compared with the other two subgroups.

Conclusions

Early microcirculatory parameters could be used to predict the survival of cardiogenic shock patients with VA-ECMO support.

Trial registration

ClinicalTrials.gov, NCT02393274. Registered on 19 March 2015.

Near-Infrared Spectroscopy Monitoring for Early Detection of Limb Ischemia in Patients on Veno-Arterial Extracorporeal Membrane Oxygenation

This study aimed to investigate the effectiveness of near-infrared spectroscopy (NIRS) monitoring for the early detection of limb ischemia in patients who were placed on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) via femoral artery. We prospectively used NIRS monitoring for the early detection of limb ischemia in 28 adult patients, who were supported with peripheral VA-ECMO between August 2013 and August 2014 (NIRS group). A decision to perform distal perfusion catheterization was made in accordance with the regional oxygen saturation (rSO2) values provided by the NIRS system. For the comparison of outcome, the medical records of 36 adult patients who had been previously supported with peripheral VA-ECMO without NIRS monitoring (Control group), between July 2012 and July 2013, were retrospectively reviewed. There was no significant difference between the frequency of distal perfusion in both groups (p = 0.435). The mean time to distal perfusion is shorter in the NIRS group (19.6 ± 21.4 vs. 42.0 ± 69.0 hours). No patient underwent fasciotomy in the NIRS group, while 13.9% did in the control group (p = 0.040). We think that NIRS monitoring is a useful and reliable method for the early detection of limb ischemia in patients undergoing peripheral VA-ECMO. Its application may allow timely correction of perfusion deficits and the prevention of compartment syndrome and limb complications.

Percutaneous Bridge to Heart Transplantation by Venoarterial ECMO and Transaortic Left Ventricular Venting

We report a case in which life support for cardiogenic shock was achieved by a nonpulsatile venoarterial bypass, and left ventricular decompression was obtained by a catheter placed percutaneously through the aortic valve into the left ventricle. The blood drained from the left ventricle was pumped into the femoral artery. The normalization of left heart filling pressures allowed the resolution of pulmonary edema, and the patient underwent a successful heart transplantation following 7 days of mechanical cardiocirculatory support.

Five-year Experience of Extracorporeal Life Support in Emergency Physicians

Background

This study aimed to present our 5-year experience of extracorporeal cardiopulmonary resuscitation (ECPR) performed by emergency physicians.

Methods

We retrospectively analyzed 58 patients who underwent ECPR between January 2010 and December 2014. The primary parameter analyzed was survival to hospital discharge. The secondary parameters analyzed were neurologic outcome at hospital discharge, cannulation time, and ECPR-related complications.

Results

Thirty-one patients (53.4%) were successfully weaned from extracorporeal membrane oxygenation, and 18 (31.0%) survived to hospital discharge. Twelve patients (20.7%) were discharged with good neurologic outcomes. The median cannulation time was 25.0 min (interquartile range 20.0-31.0 min). Nineteen patients (32.8%) had ECPR-related complications, the most frequent being distal limb ischemia. Regarding the initial presentation, 52 patients (83.9%) collapsed due to a cardiac etiology, and acute myocardial infarction (33/62, 53.2%) was the most common cause of cardiac arrest.

Conclusions

The survival to hospital discharge rate for cardiac arrest patients who underwent ECPR conducted by an emergency physician was within the acceptable limits. The cannulation time and complications following ECPR were comparable to those found in previous studies.

Microcirculatory assessment of patients under VA-ECMO

Background

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an effective technique for providing emergency mechanical circulatory support for patients with cardiogenic shock. VA-ECMO enables a rapid restoration of global systemic organ perfusion, but it has not been found to always show a parallel improvement in the microcirculation. We hypothesized in this study that the response of the microcirculation to the initiation of VA-ECMO might identify patients with increased chances of intensive care unit (ICU) survival.

Methods

Twenty-four patients were included in this study. Sublingual microcirculation measurements were performed using the CytoCam-IDF (incident dark field) imaging device. Microcirculatory measurements were performed at baseline, after VA-ECMO insertion (T1), 48–72 h after initiation of VA-ECMO (T2), 5–6 days after (T3), 9–10 days after (T4), and within 24 h of VA-ECMO removal.

Results

Of the 24 patients included in the study population, 15 survived and 9 died while on VA-ECMO. There was no significant difference between the systemic global hemodynamic variables at initiation of VA-ECMO between the survivors and non-survivors. There was, however, a significant difference in the microcirculatory parameters of both small and large vessels at all time points between the survivors and non-survivors. Perfused vessel density (PVD) at baseline (survivor versus non-survivor, 19.21 versus 13.78 mm/mm², p = 0.001) was able to predict ICU survival on initiation of VA-ECMO; the area under the receiver operating characteristic curve (ROC) was 0.908 (95 % confidence interval 0.772–1.0).

Conclusion

PVD of the sublingual microcirculation at initiation of VA-ECMO can be used to predict ICU mortality in patients with cardiogenic shock.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1519-7) contains supplementary material, which is available to authorized users.

Effects of Additional Intra-aortic Balloon Counter-Pulsation Therapy to Cardiogenic Shock Patients Supported by Extra-corporeal Membranous Oxygenation

Extra-corporeal membranous oxygenation (ECMO) has been applied in patients with cardiopulmonary failure. One critical drawback of peripheral ECMO is an increase in left ventricular (LV) afterload which could be counterbalanced by the combination of intra-aortic balloon counter-pulsation (IABP) therapy. We hypothesized that an add-on therapy with IABP could improve outcomes in patients receiving ECMO support. We included patients (>18 years old) from 2002 to 2013 requiring ECMO support due to cardiogenic shock in a medical center. A total of 529 patients (227 ECMO alone and 302 combined IABP plus ECMO) were included. The mortality rates at 2 weeks (48.5 vs. 47.7%) after ECMO implantation were not different between the two groups (ECMO vs. combined group). After adjustment for propensity score and potential confounders, the odds ratios of outcomes within 14 days (combined group vs. ECMO) for poor LV systolic function, high preload, multi-organ failure and mortality were not different. The results remained similar for subgroup analysis. Compared with ECMO alone, combined IABP and ECMO treatment did not improve outcomes in patients with circulatory failure.

Extracorporeal Membrane Oxygenation and the Kidney

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is an effective therapy for patients with reversible cardiac and/or respiratory failure. Acute kidney injury (AKI) often occurs in patients supported with ECMO; it frequently evolves into chronic kidney damage or end-stage renal disease and is associated with a reported 4-fold increase in mortality rate. Although AKI is generally due to the hemodynamic alterations associated with the baseline disease, ECMO itself may contribute to maintaining kidney dysfunction through several mechanisms.

SUMMARY

AKI may be related to conditions derived from or associated with extracorporeal therapy, leading to a reduction in renal oxygen delivery and/or to inflammatory damage. In particular, during pathological conditions requiring ECMO, the biological defense mechanisms maintaining central perfusion by a reduction of perfusion to peripheral organs (such as the kidney) have been identified as pretreatment and patient-related risk factors for AKI. Hormonal pathways are also impaired in patients supported with ECMO, leading to failures in mechanisms of renal homeostasis and worsening fluid overload. Finally, inflammatory damage, due to the primary disease, heart and lung crosstalk with the kidney or associated with extracorporeal therapy itself, may further increase the susceptibility to AKI. Renal replacement therapy can be integrated into the main extracorporeal circuit during ECMO to provide for optimal fluid management and removal of inflammatory mediators.

KEY MESSAGES

AKI is frequently observed in patients supported with ECMO. The pathophysiology of the associated AKI is chiefly related to a reduction in renal oxygen delivery and/or to inflammatory damage. Risk factors for AKI are associated with a patient's underlying disease and ECMO-related conditions.

Comparison of Extracorporeal Cardiopulmonary Resuscitation with Conventional Cardiopulmonary Resuscitation: Is Extracorporeal Cardiopulmonary Resuscitation Beneficial?

BACKGROUND

With improvements in cardiopulmonary resuscitation (CPR) techniques, the quality and the effectiveness of CPR have been established; nevertheless, the survival rate after cardiac arrest still remains poor. Recently, many reports have shown good outcomes in cases where extracorporeal membrane oxygenation (ECMO) was used during prolonged CPR. Accordingly, we attempted to evaluate the impact of extracorporeal cardiopulmonary resuscitation (ECPR) on the survival of patients who experienced a prolonged cardiac arrest and compared it with that of conventional CPR (CCPR).

METHODS

Between March 2009 and April 2014, CPR, including both in-hospital and out-of-hospital CPR, was carried out in 955 patients. The ECPR group, counted from the start of the ECPR program in March 2010, included 81 patients in total, and the CCPR group consisted of 874 patients. All data were retrospectively collected from the patients' medical records.

RESULTS

The return of spontaneous circulation (ROSC) rate was 2.24 times better in CPR of in-hospital cardiac arrest (IHCA) patients than in CPR of out-of-hospital CA (OHCA) patients (p=0.0012). For every 1-minute increase in the CPR duration, the ROSC rate decreased by 1% (p=0.0228). Further, for every 10-year decrease in the age, the rate of survival discharge increased by 31%. The CPR of IHCA patients showed a 2.49 times higher survival discharge rate than the CPR of OHCA patients (p=0.03). For every 1-minute increase in the CPR duration, the rate of survival discharge was decreased by 4%. ECPR showed superiority in terms of the survival discharge in the univariate analysis, although with no statistical significance in the multivariate analysis.

CONCLUSION

The survival discharge rate of the ECPR group was comparable to that of the CCPR group. As the CPR duration increased, the survival discharge and the ROSC rate decreased. Therefore, a continuous effort to reduce the time for the decision of ECMO initiation and ECMO team activation is necessary, particularly during the CPR of relatively young patients and IHCA patients.

Percutaneous cannulation for extracorporeal membrane oxygenation by intensivists: a retrospective single-institution case series

OBJECTIVE

Extracorporeal membrane oxygenation provides support for patients with severe acute cardiopulmonary failure, allowing the application of lung or myocardial rest in anticipation of organ recovery, or as a bridge to long-term support. Advances in technology have improved the safety and ease of application of extracorporeal membrane oxygenation. Percutaneous cannulation is one of these advances and is now preferred over surgical cannulation in most cases. Percutaneous cannulation is increasingly performed by intensivists, cardiologists, interventional radiologists, and related specialties. The objective of this study is to review the experience of percutaneous cannulation by intensivists at a single institution.

DESIGN

A retrospective review of 100 subjects undergoing percutaneous cannulation for extracorporeal membrane oxygenation.

SETTING

Adult ICUs and PICUs at a tertiary academic medical institution.

PATIENTS

Critically ill neonatal, pediatric, and adult subjects with severe respiratory and/or cardiac failure undergoing percutaneous cannulation for extracorporeal membrane oxygenation. Modes of support included venoarterial, venovenous, venovenoarterial, and arteriovenous.

INTERVENTIONS

Percutaneous extracorporeal membrane oxygenation.

MEASUREMENTS AND MAIN RESULTS

Case reports submitted to the Extracorporeal Life Support Organization and hospital records of the subjects were retrospectively reviewed. Subject demographics, type of support, cannulation configuration, types of cannulas, use of imaging modalities, and complications were recorded and summarized. One hundred ninety cannulations with cannula sizes from size 12 to 31F were performed by four intensivists in 100 subjects. Twenty-three were arterial (12-16F) and 167 were venous (12-31F). Preinsertion ultrasound was performed in 93 subjects (93%), fluoroscopic guidance in 79 subjects (85% of nonarteriovenous subjects), and ultrasound-guided insertion was performed in 65 subjects (65%). Two major complications occurred, each associated with mortality. Cannulation was successful in all other subjects (98% of subjects and 99% of cannulations). There were no cases of cannula-related bloodstream infection.

CONCLUSIONS

Percutaneous cannulation for extracorporeal membrane oxygenation by intensivists can be performed with a high rate of success and a low rate of complications when accompanied by imaging support.

Survival and quality of life after extracorporeal life support for refractory cardiac arrest: A case series

OBJECTIVES

Extracorporeal life support (ECLS) is an emerging option to treat selected patients with cardiac arrest refractory to cardiopulmonary resuscitation (CPR). Our primary objective was to determine the mortality at 30 days and at hospital discharge among adult patients receiving veno-arterial ECLS for refractory cardiac arrest. Our secondary objectives were to determine the 1-year survival and the health-related quality of life, and to examine factors associated with 30-day mortality.

METHODS

In a retrospective, single-center investigation within a tertiary referral center, we analyzed the prospectively collected data of 49 patients rescued from refractory cardiac arrest through emergent implantation of ECLS (E-CPR) (18.1% of our overall ECLS activity, 2005-2013), implanted in-hospital and during ongoing external cardiac massage in all cases. A prospective follow-up with administration of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) questionnaire was performed.

RESULTS

The mean age was 47.6 ± 1.6 years; out-of-hospital cardiac arrest occurred in 12% of cases; average low-flow time was 47.2 ± 33 minutes; causes of cardiac arrest were heart disease (61.2%), trauma (14.3%), respiratory disease (4.1%), sepsis (2%), and miscellaneous (18.4%).

PRIMARY OBJECTIVE

Rates of survival at E-CPR explantation and at 30 days were 42.9% and 36.7%, respectively; brain death occurred in 24.5% of cases.

SECONDARY OBJECTIVES

Increased simplified acute physiology score; higher serum lactate levels and lower body temperature at the time of implantation were associated with 30-day mortality. Bridge to heart transplantation or implantation of a long-term ventricular assist device was performed in 8.2%. No deaths occurred during the follow-up after discharge (36.7% survival; average follow-up was 15.6 ± 19.2 months). The average Physical Component Summary and Mental Component Summary scores (SF-36 questionnaire) were, respectively, 45.2 ± 6.8 and 48.3 ± 7.7 among survivors.

CONCLUSIONS

Extracorporeal cardiopulmonary resuscitation is a viable treatment for selected patients with cardiac arrest refractory to CPR. In our series, approximately one third of rescued patients were alive at 6 months and presented quality-of-life scores comparable to those previously observed in patients treated with ECLS.

Relationship between duration of prehospital resuscitation and favorable prognosis in ventricular fibrillation

OBJECTIVE

There appears to be an optimal point in balancing the relative benefits of extending the resuscitation time to obtain return of spontaneous circulation in the prehospital setting and the initiation of therapies such as extracorporeal cardiopulmonary resuscitation (CPR). This study investigated how prehospital CPR duration is related to survival and neurologic outcome in ventricular fibrillation (VF) and tried to find the tolerable time for prehospital resuscitation.

MATERIALS AND METHODS

Out-of-hospital cardiac arrest patients with VF in Funabashi City, Japan, from January 2009 to December 2013 were reviewed. Resuscitation teams that included physicians were dispatched to incident sites. Survival rate at 24 hours and neurologic outcome at 30 days were analyzed with respect to prehospital CPR duration.

RESULTS

A total of 172 patients were evaluated. Seventy-three patients were alive at 24 hours. Thirty-four patients had favorable neurologic outcomes after 30 days. Of the 69 patients who required prolonged prehospital CPR (>30 minutes), 6 were alive at 24 hours, and only 1 had a favorable neurologic outcome at 30 days. Logistic regression model showed that both survival rate at 24 hours and neurologic outcome at 30 days deteriorated with the increase in prehospital CPR duration (both P < .001).

CONCLUSION

The prognosis of out-of-hospital cardiac arrest patients with VF deteriorated with the increase in prehospital CPR duration. Favorable results are less likely especially in cases of prolonged prehospital CPR (>30 minutes). Therefore, it may be necessary to consider transportation to a more definitive treatment facility rather than extending conventional CPR in the prehospital setting.

Extracorporeal cardiopulmonary resuscitation

PURPOSE OF REVIEW

To discuss the role of extracorporeal membrane oxygenation (ECMO) in patients with cardiac arrest.

RECENT FINDINGS

Return to spontaneous circulation dramatically decreases with the duration of cardiopulmonary resuscitation (CPR). In this context, it has been proposed to implement venoarterial ECMO in order to assist CPR (ECPR) both in inhospital cardiac arrest (IHCA) and in out-of-hospital cardiac arrest (OHCA).

SUMMARY

This review highlights that ECPR is feasible for both IHCA and OHCA. In the recent series, the outcome of ECPR in IHCA is satisfactory, with survival rates good with neurologic outcome reaching the 40-50% range. All series converge in highlighting that time from cardiac arrest to ECMO flow is a critical determinant of outcome, with survival rates of 50% when initiated within 30 min of IHCA, 30% between 30 and 60 min, and 18% after 60 min. Results of ECPR in OHCA are more challenging. Recent series suggest that good outcome can be obtained in 15-20% of the patients, provided that time from arrest to ECMO is shorter than 60 min. Duration of cardiac arrest seems to be more important than location of cardiac arrest. ECPR thus seems to be a valuable option in selected cases.

Risk factors associated with adverse outcome following extracorporeal life support: analysis from 360 consecutive patients

OBJECTIVE

Risk factors for adverse outcome after extracorporeal life support (ECLS) are yet to be defined. For this purpose, we reviewed our institutional data from more than a decade, focusing on patients with ECLS.

METHODS

Between December 2001 and June 2013, 360 consecutive cardiac surgical patients received ECLS for post-cardiotomy cardiogenic shock, with high mortality risk despite optimal conventional therapy. Patient demographics, clinical characteristics, ECLS-related morbidity, as well as in-hospital and long-term mortality were analysed. Multivariate logistic regression analysis was performed to identify independent predictors of adverse outcome (failed ECLS weaning, in-hospital mortality).

RESULTS

The mean age was 62±17 years, 76% were male and the mean preoperative ejection fraction was 35±16%. ECLS was established through peripheral (90%) or central thoracic cannulation. The mean duration of ECLS was 7±1 days. Intra-aortic balloon pumps were implanted in 22% of the patients. ECLS weaning was successful in 58% and 30% could be discharged from hospital. The main cause of death was sepsis (69%). Overall, major cerebrovascular events occurred in 12% (bleeding 3%, embolic 9%), limb ischaemia in 13%, gastrointestinal complications in 16% and renal replacement therapy in 61%. Independent risk factors for adverse outcome were prior cardiorespiratory resuscitation (OR: 4.1, 95%CI: 0.34-4.21, p=0.04), pH <7.1 (OR: 2.8, 95%CI: 0.45-3.28, p=0.01), serum lactate >120 mg/dL (OR: 2.6, 95%CI: 0.75-2.96, p< 0.01), norepinephrine dosage >0.5 µg/kg/min (OR: 2.4, 95%CI: 0.35-2.92, p=0.02) and age >75 years (OR: 2.0, 95%CI: 0.41-2.88, p=0.02). Kaplan Meier estimates for long-term survival were 26±3% at one year and 22±2% at five years.

CONCLUSION

ECLS therapy offers one-year survival to one quarter of patients with an otherwise fatal prognosis. Procedural mortality is low and morbidity at the implantation site typically moderate. Thus, prolonged metabolic deterioration in combination with high-dose vasopressor support prior to ECLS therapy should be avoided, particularly in younger patients.

Extracorporeal versus conventional cardiopulmonary resuscitation after ventricular fibrillation cardiac arrest in rats: a feasibility trial

OBJECTIVES

Extracorporeal cardiopulmonary resuscitation with cardiopulmonary bypass potentially provides cerebral reperfusion, cardiovascular support, and temperature control for resuscitation from cardiac arrest. We hypothesized that extracorporeal cardiopulmonary resuscitation is feasible after ventricular fibrillation cardiac arrest in rats and improves outcome versus conventional cardiopulmonary resuscitation.

DESIGN

Prospective randomized study.

SETTING

University laboratory.

SUBJECTS

Adult male Sprague-Dawley rats.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Rats (intubated, instrumented with arterial and venous catheters and cardiopulmonary bypass cannulae) were randomized to conventional cardiopulmonary resuscitation, extracorporeal cardiopulmonary resuscitation with/without therapeutic hypothermia, or sham groups. After 6 minutes of ventricular fibrillation cardiac arrest, resuscitation was performed with drugs (epinephrine, sodium bicarbonate, and heparin), ventilation, either cardiopulmonary resuscitation or extracorporeal cardiopulmonary resuscitation, and defibrillation. Temperature was maintained at 37.0°C or 33.0°C for 12 hours after restoration of spontaneous circulation. Neurologic deficit scores, overall performance category, histological damage scores (viable neuron counts in CA1 hippocampus at 14 days; % of sham), and microglia proliferation and activation (Iba-1 immunohistochemistry) were assessed.

RESULTS

Extracorporeal cardiopulmonary resuscitation induced hypothermia more rapidly than surface cooling (p<0.05), although heart rate was lowest in the extracorporeal cardiopulmonary resuscitation hypothermia group (p<0.05). Survival, neurologic deficit scores, overall performance category, and surviving neurons in CA1 did not differ between groups. Hypothermia significantly reduced neuronal damage in subiculum and thalamus and increased the microglial response in CA1 at 14 days (all p<0.05). There was no benefit from extracorporeal cardiopulmonary resuscitation versus cardiopulmonary resuscitation on damage in any brain region and no synergistic benefit from extracorporeal cardiopulmonary resuscitation with hypothermia.

CONCLUSIONS

In a rat model of 6-minute ventricular fibrillation cardiac arrest, cardiopulmonary resuscitation or extracorporeal cardiopulmonary resuscitation leads to survival with intact neurologic outcomes. Twelve hours of mild hypothermia attenuated neuronal death in subiculum and thalamus but not CA1 and, surprisingly, increased the microglial response. Resuscitation from ventricular fibrillation cardiac arrest and rigorous temperature control with extracorporeal cardiopulmonary resuscitation in a rat model is feasible, regionally neuroprotective, and alters neuroinflammation versus standard resuscitation. The use of experimental extracorporeal cardiopulmonary resuscitation should be explored using longer insult durations.

Might rapid implementation of cardiopulmonary bypass in patients who are failing to recover after a cardiac arrest potentially save lives?

The question addressed was whether it might be beneficial to have a rapid-response emergency cardiopulmonary bypass service for patients who suffer an in-hospital or an out-of-hospital cardiac arrest of any aetiology. Eighty-five papers were reviewed using the reported search, of which 15 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The concept of using emergency cardiopulmonary bypass (ECPB) for the management of cardiogenic shock and refractory cardiac arrest was developed in the late 1990s. Since this time, a large number of centres worldwide have reported success with use of ECPB for cardiac arrest refractory to conventional resuscitation techniques and for cardiogenic shock. This is a relatively new advancement in resuscitative strategy and is expanding in clinical practice. Clinical studies and experimental data reveal that ECPB is a very effective tool in the return of spontaneous circulation following refractory cardiac arrest. Resuscitation with this technique demonstrated survival benefit when compared with patients having conventional cardiopulmonary resuscitation for >10 min after witnessed in-hospital arrest, especially if the cause of arrest is of cardiac origin. The reported finding from a systematic review of 1494 patients treated with ECPB noted that the overall survival rate was 47.4%; their results indicate that the application of ECPB in cardiac arrest improves survival and the likelihood of a satisfactory neurological outcome. An additional review revealed that acceptable survival rate and neurological outcomes (30%) can be achieved with extracorporeal cardiopulmonary resuscitation in children after prolonged cardiac arrest (up to 95 min) refractory to standard resuscitation. However, no study has provided clear-cut evidence of the merits of ECPS in patients with out-of-hospital cardiac arrest, although many case reports and case series have concluded that it is an effective method. We conclude that institution of emergency cardiopulmonary bypass may save the lives of patients in whom routine attempts at resuscitation after a cardiac arrest fail, especially after >10 min. The likelihood of success is much higher for patients who have in-hospital witnessed cardiac arrest.

Venous-arterial extracorporeal membrane oxygenation for refractory cardiac arrest: a clinical challenge

Guidelines stated that extracorporeal membrane oxygenation (ECMO) may improve outcomes after refractory cardiac arrest (CA) in cases of cardiogenic shock and witnessed arrest, where there is an underlying circulatory disease amenable to immediate corrective intervention. Due to the lack of randomized trials, available data are supported by small series and observational studies, being therefore characterized by heterogeneity and controversial results. In clinical practice, using ECMO involves quite a challenging medical decision in a setting where the patient is extremely vulnerable and completely dependent on the medical team's judgment. The present review focuses on examining existing evidence concerning inclusion and exclusion criteria, and outcomes (in-hospital and long-term mortality rates and neurological recovery) in studies performed in patients with refractory CA treated with ECMO. Discrepancies can be related to heterogeneity in study population, to differences in local health system organization in respect of the management of patients with CA, as well as to the fact that most investigations are retrospective. In the real world, patient selection occurs individually within each center based on their previous experience and expertise with a specific patient population and disease spectrum. Available evidence strongly suggests that in CA patients, ECMO is a highly costly intervention and optimal utilization requires a dedicated local health-care organization and expertise in the field (both for the technical implementation of the device and for the intensive care management of these patients). A careful selection of patients guarantees optimal utilization of resources and a better outcome.

A review of the fundamental principles and evidence base in the use of extracorporeal membrane oxygenation (ECMO) in critically ill adult patients

Extracorporeal membrane oxygenation (ECMO) comprises a commonly used method of extracorporeal life support. It has proven efficacy and is an accepted modality of care for isolated respiratory or cardiopulmonary failure in neonatal and pediatric populations. In adults, there are conflicting studies regarding its benefit, but it is possible that ECMO may be beneficial in certain adult populations beyond postcardiotomy heart failure. As such, all intensivists should be familiar with the evidence-base and principles of ECMO in adult population. The purpose of this article is to review the evidence and to describe the fundamental steps in initiating, adjusting, troubleshooting, and terminating ECMO so as to familiarize the intensivist with this modality.

A simple technique to prevent limb ischemia during veno-arterial ECMO using the femoral artery: the posterior tibial approach

Lower extremity ischemia is common when the femoral artery is used for veno-arterial extracorporeal membrane oxygenation (VA ECMO). We describe a new technique to reperfuse the extremity. The ipsilateral posterior tibial artery is exposed via a small incision behind the medial malleolus. The vessel is cannulated in a retrograde fashion and connected to the arterial limb of the ECMO circuit.

Thirty-six patients received a posterior tibial reperfusion cannula: average flow was 155.8 ml/min and increased over the initial 24 hours. Fifty-eight percent received the posterior tibial cannula within 6 hours of ECMO initiation and none sustained permanent lower extremity injury. Of the remaining 42%, three required amputation or developed permanent neurologic injury. Overall survival was 41%.

Cannulation of the posterior tibial artery is a simple technique to reperfuse the lower extremity during VA ECMO. The cannula should be inserted within 6 hours of ECMO initiation to avoid irreversible ischemic damage.