Extracorporeal cardiopulmonary resuscitation in patients with inhospital cardiac arrest: A comparison with conventional cardiopulmonary resuscitation

The science of reperfusion injury post cardiac arrest--Implications for emergency nurses

Survival following cardiac arrest in the developed world remains below 10%. In those who survive the initial cardiac arrest, prognosis remains poor due to the onset of multi-organ failure with both significant cardiac and neurological dysfunction. Nurses have demonstrated good understanding of cardiac arrest/post arrest guidelines and have good technical skills but deficits remain in their understanding of pathophysiological processes involved in post cardiac arrest syndromes. This article aims to provide an overview of these pathophysiological processes involved in the post cardiac arrest phase, potential treatment options and the nursing interventions that may be required within the emergency department setting. This article will focus emergency nurses to become more involved in patient management at this critical phase of treatment and highlight potential early signs of deterioration. Although return of spontaneous circulation (ROSC) is crucial in the process of recovery from cardiac arrest, it is only the first of many complex stages. Given the complexity of post cardiac arrest syndrome and its impact on the patient, healthcare professionals need to understand the cellular changes associated with reperfusion injuries in order to improve outcomes. It is only through effective nursing care and medical management that improved outcomes will become more common in the future.

Successful ECMO-cardiopulmonary resuscitation with the associated post-arrest cardiac dysfunction as demonstrated by MRI

Background

Veno-arterial extracorporeal membrane oxygenation (ECMO-CPR) is a life-saving rescue for selected patients when standard cardiopulmonary resuscitation fails. The use is increasing although the treatment modality is not fully established. Resuscitated patients typically develop a detrimental early post-arrest cardiac dysfunction that also deserves main emphasis. The present study investigates an ECMO-CPR strategy in pigs and assesses early post-arrest left ventricular function in detail. We hypothesised that a significant dysfunction could be demonstrated with this model using magnetic resonance imaging (MRI), not previously used early post-arrest.

Methods

In eight anaesthetised pigs, a 15-min ventricular fibrillation was resuscitated by an ECMO-CPR strategy of 150-min veno-arterial ECMO aiming at high blood flow rate and pharmacologically sustained aortic blood pressure and pulse pressure of 50 and 15 mmHg, respectively. Pre-arrest cardiac MRI and haemodynamic measurements of left ventricular function were compared to measurements performed 300-min post-arrest.

Results

All animals were successfully resuscitated, weaned from the ECMO circuit, and haemodynamically stabilised post-arrest. Cardiac output was maintained by an increased heart rate post-arrest, but left ventricular ejection fraction and stroke volume were decreased by approximately 50 %. Systolic circumferential strain and mitral annular plane systolic excursion as well as the left ventricular wall thickening were reduced by approximately 50–70 % post-arrest. The diastolic function variables measured were unchanged.

Conclusions

The present animal study demonstrates a successful ECMO-CPR strategy resuscitating long-lasting cardiac arrest with adequate post-arrest haemodynamic stability. The associated severe systolic left ventricular dysfunction could be charted in detail by MRI, a valuable tool for future cardiac outcome assessments in resuscitation research.

Trial registration

Institutional protocol number: FOTS 4611/13.

Electronic supplementary material

The online version of this article (doi:10.1186/s40635-015-0061-2) contains supplementary material, which is available to authorized users.

Outcome predictors in cardiopulmonary resuscitation facilitated by extracorporeal membrane oxygenation

INTRODUCTION

Cardiac arrest is the major cause of sudden death in developed countries. Extracorporeal cardiopulmonary resuscitation (ECPR) employs extracorporeal membrane oxygenation (ECMO) in patients without return of spontaneous circulation (ROSC) by conventional cardiopulmonary resuscitation (CPR). Aim of the current study was to assess short- and long-term outcome in patients treated with ECPR in our tertiary center and to identify predictors of outcome.

METHODS

We retrospectively collected data of all patients treated with ECPR at our institution from 2002 to 2013. Outcome was assessed according to patient records; good neurological outcome was defined as cerebral performance category 1 or 2. Quality of life data was collected using EQ-5 questionnaire. Uni- and multivariate analysis was applied to identify predictors of outcome.

RESULTS

One-hundred and seventeen patients were included into the study. Weaning from ECMO was successful in 61 (52 %) patients. Thirty-day survival endpoint was achieved by 27 (23 %) patients. Good neurological outcome was present in 17 (15 %) patients. Multivariate analysis revealed baseline serum lactate as the strongest predictor of outcome, whereas age and out-of-hospital CPR did not predict outcome. The optimal lactate cut-off to discriminate outcome was determined at 4.6 mmol/l [HR 3.55 (2.29-5.49), p < 0.001, log-rank test].

CONCLUSION

ECPR represents a treatment option in patients without ROSC after conventional CPR rescuing 15 % of patients with good neurological outcome. Serum lactate may play a crucial role in patient selection for ECPR.

The pre-ECMO simplified acute physiology score II as a predictor for mortality in patients with initiation ECMO support at the emergency department for acute circulatory and/or respiratory failure: a retrospective study

Background

In the emergency department (ED), extracorporeal membrane oxygenation (ECMO) can be used as a rescue treatment modality for patients with refractory circulatory and/or respiratory failure. Serious consideration must be given to the indication, and the PRESERVE and RESP scores for mortality have been investigated. However these scores were validated to predict survival in patients who received mainly veno-venous (VV) ECMO in the intensive care unit. The aim of the present study was to investigate the factors that predicted the outcomes for patients who received mixed mode (veno-arterial [VA] and VV) ECMO support in the ED.

Methods

This single center retrospective study included 65 patients who received ECMO support at the ED for circulatory or respiratory failure between January 2009 and December 2013. Pre-ECMO SAPS II and other variables were evaluated and compared for predicting mortality.

Results

Fifty-four percent of patients received ECMO-cardiopulmonary resuscitation (E-CPR), 31 % received VA and V-AV ECMO, and 15 % received VV ECMO. The 28-day and 60-month mortality rates were 52 % and 63 %. In the multivariate analysis, only the pre-ECMO Simplified Acute Physiology Score II (SAPS II) (odd ratio: 1.189, 95 % confidence interval: 1.032–1.370, p = 0.016) could predict the 28-day mortality. The area under the receiver operating characteristic curve and the optimal cutoff value for pre-ECMO SAPS II in predicting 28-day mortality was 0.852 (95 % CI: 0.753–0.951, p < 0.001) and 80 (sensitivity of 97.1 % and specificity of 71.0 %), respectively. Validation of the 80 cutoff value revealed a statistically significant difference for the 28-day and 60-month mortality rates in the overall, E-CPR, and VA groups (28-day: p < 0.001, p = 0.004, p = 0.005; 60-month: p < 0.001, p = 0.004, p = 0.020). In the Kaplan-Meier analysis, the 28-day and 60-month survival rates were lower among the patients with a pre-ECMO SAPS II of ≤80, compared to those with a score of >80 (both, p < 0.001).

Conclusion

The pre-ECMO SAPS II could be helpful for identifying patients with refractory acute circulatory and/or respiratory failure who will respond to ECMO support in the ED.

Extra Corporeal Membrane Oxygenation (ECMO) review of a lifesaving technology

Extra Corporeal Membrane Oxygenation (ECMO) indications and usage has strikingly progressed over the last 20 years; it has become essential tool in the care of adults and children with severe cardiac and pulmonary dysfunction refractory to conventional management. In this article we will provide a review of ECMO development, clinical indications, patients' management, options and cannulations techniques, complications, outcomes, and the appropriate strategy of organ management while on ECMO.

Extracorporeal membrane oxygenation for cardiac arrest during moyamoya cerebral revascularization surgery: case report

The authors describe the case of a 51-year-old man with bilateral moyamoya disease and prior strokes who developed an asystolic cardiac arrest while undergoing revascularization surgery under mild hypothermia. The patient was successfully treated with venoarterial (VA) extracorporeal membrane oxygenation (ECMO) after manual cardiopulmonary resuscitation (CPR) was unsuccessful for 45 minutes. ECMO is a cardiopulmonary support system that is indicated for respiratory failure in pediatric and adult patients. It is increasingly being used as an extension to mechanical CPR for patients who have suffered cardiac arrest if the underlying cause of cardiac arrest is thought to be reversible. Identifying which patients should be placed on emergency ECMO after cardiac arrest is controversial given its high morbidity and mortality. ECMO in neurosurgical settings has associated risks of intracranial hemorrhage and neurological compromise, while resource utilization is paramount given the high costs of this treatment. This paper is significant because it describes the use of ECMO in an unindicated setting. Limited data are available for ECMO usage after cardiac arrest with baseline cerebral ischemia. Furthermore, this paper raises important considerations for extracorporeal CPR use in a patient who had recently undergone craniotomy. The patient in this report remained on ECMO for 48 hours, after which he was successfully weaned. He developed a pericardial effusion and compartment syndrome from the ECMO but made a complete neurological recovery. Use of ECMO emergently in an appropriately chosen neurosurgical patient is safe, even in the setting of baseline cerebral ischemia and recent craniotomy.

Cardiogenic Shock

Cardiogenic shock is the leading cause of morbidity and mortality in patients presenting with acute coronary syndrome. Although early reperfusion strategies are essential to the management of these critically ill patients, additional treatment plans are often needed to stabilize and treat the patient before reperfusion may be possible. This article discusses pharmacologic and surgical interventions, their indications and contraindications, management strategies, and treatment algorithms.

Extracorporeal Membrane Oxygenation Support for Hypokalemia-induced Cardiac Arrest: A Case Report and Review of the Literature

BACKGROUND

Hypokalemia is a reversible cause of cardiac arrest in patients presenting to the emergency department (ED). Extracorporeal membrane oxygenation (ECMO) is an established technology for cardiopulmonary support with emerging roles in resuscitation. Here, we review the literature of hypokalemic-induced cardiac arrests and discuss one such case successfully managed with ECMO.

CASE REPORT

A 23-year-old Central American man who presented to a community ED under federal custody with several days of nausea and vomiting was found to have a serum potassium level of 1.5 mEq/L. Repeat serum potassium level was 1.1 mEq/L upon arrival to our facility. Within 2 h of arrival, despite electrolyte repletion, he suffered cardiac arrest. Advanced cardiac life support was performed for 45 min. ECMO was initiated while active chest compressions were performed. After aggressive potassium repletion, return of spontaneous circulation was achieved and ECMO was eventually discontinued. Further investigation ultimately confirmed the presence of a potassium-wasting nephropathy, for which the patient had been treated with chronic potassium supplementation prior to entering federal custody. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: ECMO is a well-established modality for cardiopulmonary support, with an emerging role for patients in undifferentiated cardiac arrest presenting to the ED. There is a growing interest in the utility of ECMO in these circumstances. This report highlights hypokalemia as an important cause of cardiac arrest, reviews the treatment and causes of hypokalemia, and demonstrates a potential role for ECMO as a critical temporizing measure to provide time for potassium repletion.

Veno-arterial extracorporeal membrane oxygenation for adult cardiovascular failure

PURPOSE OF REVIEW

To examine the utility and technical challenges of applying veno-arterial extracorporeal membrane oxygenation for acute cardiovascular failure in adults with acute and chronic causes of heart failure.

RECENT FINDINGS

The role of mechanical circulatory support in acute cardiovascular continues to evolve as technology and clinical experience develop. There is increasing interest in the role of veno-arterial extracorporeal membrane oxygenation as a bridging therapy and as an adjunct to conventional cardiopulmonary resuscitation.

SUMMARY

Veno-arterial extracorporeal membrane oxygenation is an expensive, complex, resource intensive support. It is essential that its future use be guided by evidence obtained from centres that have demonstrated timely, safe support.

[Near-infrared spectroscopy during cardiopulmonary resuscitation and mechanical circulatory support: From the operating room to the intensive care unit]

BACKGROUND

Near infrared spectroscopy (NIRS) allows continuous measurement of cerebral regional oxygen saturation (rSO2). It is a weighted saturation value derived from approximately 70-75 % venous, 20-25 % arterial and 2.5-5 % capillary blood. In contrast to pulse oximetry, NIRS is independent of pulsatile flow. Therefore, it is also applicable during extracorporeal circulation, cardiopulmonary resuscitation (CPR), and hypothermia.

OBJECTIVES

The purpose of this work is to describe the application of cerebral and somatic NIRS in cardiology and cardiac surgery patients in the operation room, during and after CPR, and during the intensive care unit stay.

MATERIALS AND METHODS

This article is based on peer-reviewed literature from PubMed.

RESULTS

Interventions based on decline of cerebral NIRS values during on-pump cardiac surgery can reduce major organ morbidity and mortality; however, the appearance of a postoperative cognitive dysfunction is scarcely influenced. Persisting of low cerebral oximetry values during resuscitation is a marker for not achieving return of spontaneous circulation under normothermia. NIRS is an additional method for monitoring that can be used during extracorporeal circulation.

CONCLUSION

NIRS is a rapidly available, user-friendly, and noninvasive method for continuous measurement of rSO2. NIRS provides additional information about tissue oxygenation especially during resuscitation and extracorporeal circulatory assist support. Recommendations concerning the use of NIRS for standard monitoring during resuscitation and mechanical circulatory support are not currently available. Further studies are required to show if use of NIRS can reduce pulse control and hands-off times during resuscitation and if use of NIRS can improve outcome after CPR and mechanical circulatory support.

Venoarterial Extracorporeal Membrane Oxygenation in Adults With Cardiac Arrest

Cardiac arrest (CA) is a major cause of morbidity and mortality worldwide. Despite the use of conventional cardiopulmonary resuscitation (CPR), rates of return of spontaneous circulation and survival with minimal neurologic impairment remain low. Utilization of venoarterial extracorporeal membrane oxygenation (ECMO) for CA in adults is steadily increasing. Propensity-matched cohort studies have reported outcomes associated with ECMO use to be superior to that of conventional CPR alone in in-hospital patients with CA. In this review, we discuss the mechanism, indications, complications, and evidence for ECMO in CA in adults.

Extracorporeal life support for adult cardiopulmonary failure

The use of extracorporeal life support (ECLS) or extracorporeal membrane oxygenation (ECMO), as it is also known, has rapidly expanded over the past decade. The increase in ECMO use is a consequence of multiple factors including significant advancements in extracorporeal technology, the emergence of data supporting its use, and a growing number of potential clinical applications. This review focuses on the various modes of ECLS as well as the clinical indications and available evidence for the use of extracorporeal support.

[Use of ECMO in adult patients with cardiogenic shock: a position paper of the Austrian Society of Cardiology]

The use of ECMO to stabilize critically ill patients with severely depressed cardiac function and hemodynamics increased in the last years due to broader availability, better performance and easier implantation of the devices. The present guidelines of the Austrian Society of Cardiology focus on the use of ECMO in adult non-operated patients with cardiac diseases. Not only indications and contraindications are highlighted, but also the equally important issues of monitoring, complication management, measures during implantation and operation, and weaning of the devices are treated in detail. Thereby the present guidelines aim to optimize the use of ECMO in the individual centers, and aim to help current non-ECMO centers in developing a local ECMO-program or to contact ECMO-centers for discussion of individual patients.

Predictors of neurological outcomes after successful extracorporeal cardiopulmonary resuscitation

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) refers to use of extracorporeal membrane oxygenation (ECMO) in cardiopulmonary arrest. Although ECPR can increase survival rates after cardiac arrest, it can also result in poor post-resuscitation neurological status. Thus, we investigated predictors of good neurological outcomes after successful ECPR.

METHODS

A total of 227 patients underwent ECPR from May 2004 to June 2013 at Samsung Medical Center. Successful ECPR was defined as survival more than 24 hours after ECPR. Neurological outcomes were assessed at discharge using the Glasgow-Pittsburgh Cerebral Performance Categories scale (CPC). CPC 1 and 2 were classified as good and CPC 3 to 5 were classified as poor neurological outcomes. Excluded were 22 patients who did not survive more than 24 hours after ECPR and 90 patients who died from unknown causes or causes other than brain death or whose neurological status could not be assessed at discharge. Multiple logistic regression analysis was used to identify independent predictors of neurological outcomes.

RESULTS

Included were 115 patients with a mean age of 58 (range 45-66) years and 80 men (70%). Cardiopulmonary resuscitation (CPR) was performed at non-hospital sites for 19 (17%) patients and bystander CPR was performed in 9 of 19 cases (47%). Cardiac etiology was verified in 74 (64%) patients and therapeutic hypothermia was performed in 9 patients (8%); 68 (59%) had good neurological outcomes and 47 (41%) did not and 24 patients died from brain death. Neurological outcomes were affected by hemoglobin levels before ECMO (P = 0.02), serum lactic acid (P < 0.001) before ECMO insertion, and interval from cardiac arrest to ECMO (P = 0.04).

CONCLUSIONS

Low hemoglobin or high serum lactic acid levels before ECMO, and prolonged interval from cardiac arrest to ECMO predicted poor neurological outcomes after successful ECPR. Early institution of ECMO and a low threshold for blood transfusion might improve neurological outcomes for patients who survive ECPR.

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.

Current experience and limitations of extracorporeal cardiopulmonary resuscitation for cardiac arrest in children: a single-center retrospective study

Background

There are few reports detailing the importance of extracorporeal membrane oxygenation (ECMO) for pediatric cardiac arrest in Japan. We investigated the status and issues surrounding extracorporeal cardiopulmonary resuscitation (ECPR) at our institution.

Methods

Patients aged <15 years who underwent ECPR between April 1, 2003 and March 31, 2012 were eligible. The characteristics, cannulation site, durations of cardiopulmonary resuscitation (CPR), cannulation procedure, and ECMO, and neurologic outcomes were retrospectively reviewed. A favorable neurologic outcome was defined as Pediatric Cerebral Performance Categories 1 and 2.

Results

A total of 21 ECPR events were identified. The median CPR and cannulation durations were 60 and 25 min, respectively. Central and peripheral access sites were employed in 15 and six cases, respectively. Five of the 21 patients (24%) were successfully weaned from ECMO and three of the 21 (14%) survived. Two of the three survivors had a favorable neurologic outcome.

Conclusions

The mortality of patients undergoing ECPR at our institution was low. However, about 10% of all patients had a favorable neurologic outcome, which suggests that ECPR may be effective in pediatric cardiac arrest patients.

Extracorporeal membrane oxygenation-hemostatic complications

The use of extracorporeal membrane oxygenation (ECMO) support for cardiac and respiratory failure has increased in recent years. Improvements in ECMO oxygenator and pump technologies have aided this increase in utilization. Additionally, reports of successful outcomes in supporting patients with respiratory failure during the 2009 H1N1 pandemic and reports of ECMO during cardiopulmonary resuscitation have led to increased uptake of ECMO. Patients requiring ECMO are a heterogenous group of critically ill patients with cardiac and respiratory failure. Bleeding and thrombotic complications remain a leading cause of morbidity and mortality in patients on ECMO. In this review, we describe the mechanisms and management of hemostatic, thrombotic and hemolytic complications during ECMO support.

Examination of physiological function and biochemical disorders in a rat model of prolonged asphyxia-induced cardiac arrest followed by cardio pulmonary bypass resuscitation

Background

Cardiac arrest induces whole body ischemia, which causes damage to multiple organs particularly the heart and the brain. There is clinical and preclinical evidence that neurological injury is responsible for high mortality and morbidity of patients even after successful cardiopulmonary resuscitation. A better understanding of the metabolic alterations in the brain during ischemia will enable the development of better targeted resuscitation protocols that repair the ischemic damage and minimize the additional damage caused by reperfusion.

Method

A validated whole body model of rodent arrest followed by resuscitation was utilized; animals were randomized into three groups: control, 30 minute asphyxial arrest, or 30 minutes asphyxial arrest followed by 60 min cardiopulmonary bypass (CPB) resuscitation. Blood gases and hemodynamics were monitored during the procedures. An untargeted metabolic survey of heart and brain tissues following cardiac arrest and after CPB resuscitation was conducted to better define the alterations associated with each condition.

Results

After 30 min cardiac arrest and 60 min CPB, the rats exhibited no observable brain function and weakened heart function in a physiological assessment. Heart and brain tissues harvested following 30 min ischemia had significant changes in the concentration of metabolites in lipid and carbohydrate metabolism. In addition, the brain had increased lysophospholipid content. CPB resuscitation significantly normalized metabolite concentrations in the heart tissue, but not in the brain tissue.

Conclusion

The observation that metabolic alterations are seen primarily during cardiac arrest suggests that the events of ischemia are the major cause of neurological damage in our rat model of asphyxia-CPB resuscitation. Impaired glycolysis and increased lysophospholipids observed only in the brain suggest that altered energy metabolism and phospholipid degradation may be a central mechanism in unresuscitatable brain damage.

Clinical Applications of Extracorporeal Membranous Oxygenation: A Mini-Review

The clinical usage of extracorporeal membranous oxygenation began more than 40 years ago. Although the indications for its use have expanded over the years, it has been challenging to conduct randomized controlled trials to prove that extracorporeal membranous oxygenation is more effective than traditional approaches. Through a review of retrospective reports and data from registries, we attempted to evaluate the appropriateness of its application for acute respiratory distress syndrome, cardiopulmonary resuscitation, postcardiotomy cardiogenic shock, and sepsis. Our investigation revealed that using extracorporeal membranous oxygenation when readily available is appropriate for all patients with cardiopulmonary resuscitation or postcardiotomy cardiogenic shock, and for selected patients with acute respiratory distress syndrome or sepsis.

KEY WORDS

Acute respiratory distress syndrome; Cardiopulmonary resuscitation; Extracorporeal membranous oxygenation; Postcardiotomy cardiogenic shock; Sepsis.

Refractory cardiac arrest treated with mechanical CPR, hypothermia, ECMO and early reperfusion (the CHEER trial)

INTRODUCTION

Many patients who suffer cardiac arrest do not respond to standard cardiopulmonary resuscitation. There is growing interest in utilizing veno-arterial extracorporeal membrane oxygenation assisted cardiopulmonary resuscitation (E-CPR) in the management of refractory cardiac arrest. We describe our preliminary experiences in establishing an E-CPR program for refractory cardiac arrest in Melbourne, Australia.

METHODS

The CHEER trial (mechanical CPR, Hypothermia, ECMO and Early Reperfusion) is a single center, prospective, observational study conducted at The Alfred Hospital. The CHEER protocol was developed for selected patients with refractory in-hospital and out-of-hospital cardiac arrest and involves mechanical CPR, rapid intravenous administration of 30 mL/kg of ice-cold saline to induce intra-arrest therapeutic hypothermia, percutaneous cannulation of the femoral artery and vein by two critical care physicians and commencement of veno-arterial ECMO. Subsequently, patients with suspected coronary artery occlusion are transferred to the cardiac catheterization laboratory for coronary angiography. Therapeutic hypothermia (33 °C) is maintained for 24h in the intensive care unit.

RESULTS

There were 26 patients eligible for the CHEER protocol (11 with OHCA, 15 with IHCA). The median age was 52 (IQR 38-60) years. ECMO was established in 24 (92%), with a median time from collapse until initiation of ECMO of 56 (IQR 40-85) min. Percutaneous coronary intervention was performed on 11 (42%) and pulmonary embolectomy on 1 patient. Return of spontaneous circulation was achieved in 25 (96%) patients. Median duration of ECMO support was 2 (IQR 1-5) days, with 13/24 (54%) of patients successfully weaned from ECMO support. Survival to hospital discharge with full neurological recovery (CPC score 1) occurred in 14/26 (54%) patients.

CONCLUSIONS

A protocol including E-CPR instituted by critical care physicians for refractory cardiac arrest which includes mechanical CPR, peri-arrest therapeutic hypothermia and ECMO is feasible and associated with a relatively high survival rate.

An optimal transition time to extracorporeal cardiopulmonary resuscitation for predicting good neurological outcome in patients with out-of-hospital cardiac arrest: a propensity-matched study

INTRODUCTION

Prolonged conventional cardiopulmonary resuscitation (CCPR) is associated with a poor prognosis in out-of-hospital cardiac arrest (OHCA) patients. Alternative methods can be needed to improve the outcome in patients with prolonged CCPR and extracorporeal cardiopulmonary resuscitation (ECPR) can be considered as an alternative method. The objectives of this study were to estimate the optimal duration of CPR to consider ECPR as an alternative resuscitation method in patients with CCPR, and to find the indications for predicting good neurologic outcome in OHCA patients who received ECPR.

METHODS

This study is a retrospective analysis based on a prospective cohort. We included patients ≥ 18 years of age without suspected or confirmed trauma and who experienced an OHCA from May 2006 to December 2013. First, we determined the appropriate cut-off duration for CPR based on the discrimination of good and poor neurological outcomes in the patients who received only CCPR, and then we compared the outcome between the CCPR group and ECPR group by using propensity score matching. Second, we compared CPR related data according to the neurologic outcome in matched ECPR group.

RESULTS

Of 499 patients suitable for inclusion, 444 and 55 patients were enrolled in the CCPR and ECPR group, respectively. The predicted duration for a favorable neurologic outcome (CPC1, 2) is < 21 minutes of CPR in only CCPR patients. The matched ECPR group with ≥ 21 minutes of CPR duration had a more favorable neurological outcome than the matched CCPR group at 3 months post-arrest. In matched ECPR group, younger age, witnessed arrest without initial asystole rhythm, early achievement of mean arterial pressure ≥ 60 mmHg, low rate of ECPR-related complications, and therapeutic hypothermia were significant factors for expecting good neurologic outcome.

CONCLUSIONS

ECPR should be considered as an alternative method for attaining good neurological outcomes in OHCA patients who required prolonged CPR, especially of ≥ 21 minutes. Younger or witnessed arrest patients without initial asystole were good candidates for ECPR. After implantation of ECPR, early hemodynamic stabilization, prevention of ECPR-related complications, and application of therapeutic hypothermia may improve the neurological outcome.

Extracorporeal life support in critically ill adults

Extracorporeal life support (ECLS) has become increasingly popular as a salvage strategy for critically ill adults. Major advances in technology and the severe acute respiratory distress syndrome that characterized the 2009 influenza A(H1N1) pandemic have stimulated renewed interest in the use of venovenous extracorporeal membrane oxygenation (ECMO) and extracorporeal carbon dioxide removal to support the respiratory system. Theoretical advantages of ECLS for respiratory failure include the ability to rest the lungs by avoiding injurious mechanical ventilator settings and the potential to facilitate early mobilization, which may be advantageous for bridging to recovery or to lung transplantation. The use of venoarterial ECMO has been expanded and applied to critically ill adults with hemodynamic compromise from a variety of etiologies, beyond postcardiotomy failure. Although technology and general care of the ECLS patient have evolved, ECLS is not without potentially serious complications and remains unproven as a treatment modality. The therapy is now being tested in clinical trials, although numerous questions remain about the application of ECLS and its impact on outcomes in critically ill adults.

Mechanical circulatory support

The role for temporary and durable mechanical circulatory support is rapidly expanding. As the use of these technologies continues to grow, the emergency physician has an increasing opportunity to participate in the advancement of these potentially life-saving technologies. This review discusses the current role of the intra-aortic balloon pump in cardiogenic shock, describes the complications and management strategies for the critically ill patient with a left ventricular assist device, and explores the emerging role of ECMO in the emergency department for patients presenting in refractory cardiogenic shock and cardiac arrest.

Clinical outcomes of patients with acute myocardial infarction complicated by severe refractory cardiogenic shock assisted with percutaneous cardiopulmonary support

PURPOSE

Limited data are available on the role of percutaneous cardiopulmonary support (PCPS) for the treatment of acute myocardial infarction (AMI) patients with cardiogenic shock. We investigated the clinical outcomes and predictors of in-hospital mortality after PCPS in patients with AMI complicated by severe refractory cardiogenic shock.

MATERIALS AND METHODS

From January 2004 to December 2011, we analyzed data from 96 consecutive AMI patients with cardiogenic shock assisted by a PCPS system. The primary outcome was in-hospital mortality. The predictors of in-hospital mortality were determined by a Cox proportional-hazards model.

RESULTS

In-hospital mortality occurred in 51 (53.1%) patients and 58 (60.4%) patients were able to be weaned from PCPS. Cardiopulmonary resuscitation (CPR) was performed in 61 (63.5%) patients before PCPS initiation. On multivariate analysis, age≥67 years [adjusted hazard ratio (HR), 4.74; 95% confidence interval (CI), 2.27-9.93; p<0.001], CPR (adjusted HR, 2.32; 95% CI, 1.11-4.85; p=0.03), lactate clearance for 48 hours<70% (adjusted HR, 2.50; 95% CI, 1.04-6.05; p=0.041), and unsuccessful revascularization (adjusted HR, 3.57; 95% CI, 1.85-6.90; p=0.002) were independent predictors of in-hospital mortality after PCPS in patients with AMI complicated by cardiogenic shock.

CONCLUSION

In spite of PCPS management, AMI patients complicated by severe refractory cardiogenic shock demonstrated high mortality. Older age, CPR, lower lactate clearance for 48 hours, and unsuccessful revascularization were independent predictors of in-hospital mortality.

Pediatric and neonatal extracorporeal membrane oxygenation: does center volume impact mortality?*

OBJECTIVE

Extracorporeal membrane oxygenation, an accepted rescue therapy for refractory cardiopulmonary failure, requires a complex multidisciplinary approach and advanced technology. Little is known about the relationship between a center's case volume and patient mortality. The purpose of this study was to analyze the relationship between hospital extracorporeal membrane oxygenation annual volume and in-hospital mortality and assess if a minimum hospital volume could be recommended.

DESIGN

Retrospective cohort study.

SETTING

A retrospective cohort admitted to children's hospitals in the Pediatric Health Information System database from 2004 to 2011 supported with extracorporeal membrane oxygenation was identified. Indications were assigned based on patient age (neonatal vs pediatric), diagnosis, and procedure codes. Average hospital annual volume was defined as 0-19, 20-49, or greater than or equal to 50 cases per year. Maximum likelihood estimates were used to assess minimum annual case volume.

PATIENTS

A total of 7,322 pediatric patients aged 0-18 were supported with extracorporeal membrane oxygenation and had an indication assigned.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Average hospital extracorporeal membrane oxygenation volume ranged from 1 to 58 cases per year. Overall mortality was 43% but differed significantly by indication. After adjustment for case-mix, complexity of cardiac surgery, and year of treatment, patients treated at medium-volume centers (odds ratio, 0.86; 95% CI, 0.75-0.98) and high-volume centers (odds ratio, 0.75; 95% CI, 0.63-0.89) had significantly lower odds of death compared with those treated at low-volume centers. The minimum annual case load most significantly associated with lower mortality was 22 (95% CI, 22-28).

CONCLUSIONS

Pediatric centers with low extracorporeal membrane oxygenation average annual case volume had significantly higher mortality and a minimum volume of 22 cases per year was associated with improved mortality. We suggest that this threshold should be evaluated by additional study.

Extracorporeal membrane oxygenation for resuscitation and cardiac arrest management

This article reviews the potential application of extracorporeal membrane oxygenation (ECMO) technology to cardiopulmonary resuscitation for in and out-of-hospital cardiac arrest and discusses the current evidence on the subject. The possible strategies for organ protection during ECMO and the concept of ECMO networks are also reviewed.

Outcomes of percutaneous femoral cannulation for venoarterial extracorporeal membrane oxygenation support

INTRODUCTION

We report and examine the outcomes of emergency venoarterial extracorporeal membrane oxygenation (ECMO) support initiated via percutaneous cannulation of the femoral vessels.

PATIENTS AND METHODS

Fifteen patients undergoing percutaneous venoarterial ECMO under emergency circumstances between January 2009 and July 2011 were identified. The implantation technique employed the Seldinger's technique for both arterial and venous cannulae. Whenever possible antegrade perfusion of the ipsilateral lower limb was performed through percutaneous catheterization of the superficial femoral artery (SFA).

RESULTS

ECMO support was indicated mainly for cardiac arrest (n=9, 60%) or cardiogenic shock (n=4, 27%), while two (13%) patients required ECMO support for acute respiratory failure. In five (33%) patients, ECMO was implanted during cardiopulmonary resuscitation manoeuvres. ECMO support was maintained for a mean of 4.9 days. Eight patients (53%) were successfully weaned from the device. Thirty-day mortality was 53%. Seven patients (47%) suffered early complications, namely two wound infections, one thrombosis of the venous cannula, one erroneous implantation of the arterial cannula into the femoral vein, one local dissection of the femoral artery, one retroperitoneal bleeding and one acute limb ischaemia. No long-term vascular complications were noted.

CONCLUSION

Percutaneous femoral cannulation for ECMO support remains a prompt approach for establishing extracorporeal circulatory support in acute cardiopulmonary failure when conditions for performing femoral vessel cut down are not optimal. However, vascular complications are frequent and carry a significant morbidity and mortality.

Cerebral oximetry and cardiac arrest

Cerebral oximetry is a Food and Drug Administration-approved technology that allows monitoring of brain oxygen saturation in accessible superficial brain cortex regions, which are amongst the most vulnerable in regard to ischemic or hypoxic injury. Since most oxygen in the area of interest is located in the venous compartment, the determined regional brain oxygen saturation approximately reflects the local balance between oxygen delivery and oxygen consumption. Major systemic alterations in blood oxygen content and oxygen delivery will be accompanied by corresponding changes in regional brain saturation. This systematic review, which is based on a Medline search, focuses on the characteristic changes in regional cerebral oxygen saturation that occur, when global oxygen supply to the brain ceases. It further highlights the potential application of cerebral oximetry in the management of cardiac arrest victims, the predictability of clinical outcome after global cerebral ischemia, and it also indicates possible potentials for the management of cerebral reperfusion after having instituted return of spontaneous circulation.

Pediatric extracorporeal life support in specialized situations

OBJECTIVES

The purpose of this review was to provide a systematic review of the literature regarding the use of extracorporeal life support (ECLS) in various specialized conditions, as part of the Pediatric Cardiac Intensive Care Society/Extracorporeal Life Support Organization Joint Statement on Mechanical Circulatory Support.

DATA SOURCES

MEDLINE and PubMed.

STUDY SELECTION

Searches for published abstracts and articles were conducted using the following MeSH terms: extracorporeal life support, extracorporeal membrane oxygenation, or mechanical support, and pediatric or children.

DATA EXTRACTION

Abstracts of all articles including case reports were reviewed; the full article was reviewed if the abstract indicated that it focused on extracorporeal life support for conditions other than primary respiratory disease or persistent pulmonary hypertension of the newborn and described outcomes such as survival to hospital discharge. Studies with potential overlapping patients were highlighted in the review process and summary results.

DATA SYNTHESIS

Classification of recommendations and level of evidence are expressed in the American College of Cardiology Foundation/American Heart Association format.

CONCLUSIONS

The majority of specialized situations where extracorporeal life support is used fall into the category of class II-III evidence. Class I indications for extracorporeal life support in the pediatric population include myocarditis and in the context of acute interventions in the cardiac catheterization laboratory.

Out-of-hospital cardiac arrest: 10 years of progress in research and treatment

Cardiac disease is the most common cause of mortality in Western countries, with most deaths due to out-of-hospital cardiac arrest (OHCA). In Sweden, 5000-10 000 OHCAs occur annually. During the last decade, the time from cardiac arrest to start of cardiopulmonary resuscitation (CPR) and defibrillation has increased, whereas survival has remained unchanged or even increased. Resuscitation of OHCA patients is based on the 'chain-of-survival' concept, including early (i) access, (ii) CPR, (iii) defibrillation, (iv) advanced cardiac life support and (v) post-resuscitation care. Regarding early access, agonal breathing, telephone-guided CPR and the use of 'track and trigger systems' to detect deterioration in patients' condition prior to an arrest are all important. The use of compression-only CPR by bystanders as an alternative to standard CPR in OHCA has been debated. Based on recent findings, guidelines recommend telephone-guided chest compression-only CPR for untrained rescuers, but trained personnel are still advised to give standard CPR with both compressions and ventilation, and the method of choice for this large group remains unclear and demands for a randomized study. Data have shown the benefit of public access defibrillation for dispatched rescuers (e.g. police and fire fighters) but data are not as strong for the use of automated defibrillators (AEDs) by trained or untrained rescuers. Postresuscitation, use of therapeutic hypothermia, the importance of specific prognostic survival factors in the intensive care unit and the widespread use of percutaneous coronary intervention have all been considered. Despite progress in research and improved treatment regimens, most patients do not survive OHCA. Particular areas of interest for improving survival include (i) identification of high-risk patients prior to their arrest (e.g. early warning symptoms and genes); (ii) increased use of bystander CPR training (e.g. in schools) and simplified CPR techniques; (iii) better identification of high-incidence sites and better recruitment of AEDs (via mobile phone solutions?); (iv) improved understanding of the use of therapeutic hypothermia; (v) determining which patients should undergo immediate coronary angiography on hospital admission; and (vi) clarifying the importance of extracorporeal membrane oxygenation during CPR.