Emergency cardio-pulmonary bypass in cardiac arrest: Seventeen years of experience

Mechanistic and therapeutic role of Drp1 in the pathogenesis of stroke

Stroke had emerged as one of the leading causes of death and long-term disability across the globe. Emerging evidence suggests a significant increase in the incidence of stroke with age, which is further expected to increase dramatically owing to an ever-expanding elderly population. The current situation imposes a significant burden on the healthcare system and requires a deeper understanding of the underlying mechanisms and development of novel interventions. It is well established that mitochondrial dysfunction plays a pivotal role in the onset of stroke. Dynamin-related protein 1 (Drp1), is a key regulator of mitochondria fission, and plays a crucial role during the pathogenesis of stroke. Drp1 protein levels significantly increase after stroke potentially in a p38 mitogen-activated protein kinases (MAPK) dependent manner. Protein phosphatase 2A (PP2A) facilitate mitochondrial fission and cell death by dephosphorylating the mitochondrial fission enzyme Drp1 at the inhibitory phosphorylation site serine 637. Outer mitochondrial membrane A-Kinase Anchoring Proteins 1 (AKAP 1) and protein kinase A complex (PKA) complex inhibits Drp1-dependent mitochondrial fission by phosphorylating serine 637. Drp1 activation promotes the release of cytochrome C from mitochondria and therefore leads to apoptosis. In addition, Drp1 activation inhibits mitochondrial glutathione dependent free radical scavenging, which further enhances the ROS level and exacerbate mitochondrial dysfunction. Drp1 translocate p53 to mitochondrial membrane and leads to mitochondria-related necrosis. The current review article discusses the possible mechanistic pathways by which Drp1 can influence the pathogenesis of stroke. Besides, it will describe various inhibitors for Drp1 and their potential role as therapeutics for stroke in the future.

Initial rhythm and survival in refractory out-of-hospital cardiac arrest. Post-hoc analysis of the Prague OHCA randomized trial

BACKGROUND

The prognosis of refractory out-of-hospital cardiac arrest (OHCA) is generally poor. A recent Prague OHCA study has demonstrated that an invasive approach (including extracorporeal cardiopulmonary resuscitation, ECPR) is a feasible and effective treatment strategy in refractory OHCA. Here we present a post-hoc analysis of the role of initial rhythm on patient outcomes.

METHODS

The study enrolled patients who had a witnessed OHCA of presumed cardiac cause without early recovery of spontaneous circulation. The initial rhythm was classified as either a shockable or a non-shockable rhythm. The primary outcome was a composite of 180 day-survival with Cerebral Performance in Category 1 or 2.

RESULTS

256 (median age 58y, 17% females) patients were enrolled. The median (IQR) duration of resuscitation was 52 (33-68) minutes. 156 (61%) and 100 (39%) of patients manifested a shockable and non-shockable rhythm, respectively. The primary outcome was achieved in 63 (40%) patients with a shockable rhythm and in 5 (5%) patients with a non-shockable rhythm (p < 0.001). When patients were analyzed separately based on whether the treatment was invasive (n = 124) or standard (n = 132), the difference in the primary endpoint between shockable and non-shockable initial rhythms remained significant (35/72 (49%) vs 4/52 (8%) in the invasive arm and 28/84 (33%) vs 1/48 (2%) in the standard arm; p < 0.001).

CONCLUSION

An initial shockable rhythm and treatment with an invasive approach is associated with a reasonable neurologically favorable survival for 180 days despite refractory OHCA. Non-shockable initial rhythms bear a poor prognosis in refractory OHCA even when ECPR is readily available.

Local anesthetic systemic toxicity: A narrative review for emergency clinicians

INTRODUCTION

Emergency clinicians utilize local anesthetics for a variety of procedures in the emergency department (ED) setting. Local anesthetic systemic toxicity (LAST) is a potentially deadly complication.

OBJECTIVE

This narrative review provides emergency clinicians with the most current evidence regarding the pathophysiology, evaluation, and management of patients with LAST.

DISCUSSION

LAST is an uncommon but potentially life-threatening complication of local anesthetic use that may be encountered in the ED. Patients at extremes of age or with organ dysfunction are at higher risk. Inadvertent intra-arterial or intravenous injection, as well as repeated doses and higher doses of local anesthetics are associated with greater risk of developing LAST. Neurologic and cardiovascular manifestations can occur. Early recognition and intervention, including supportive care and intravenous lipid emulsion 20%, are the mainstays of treatment. Using ultrasound guidance, aspirating prior to injection, and utilizing the minimal local anesthetic dose needed are techniques that can reduce the risk of LAST.

CONCLUSIONS

This focused review provides an update for the emergency clinician to manage patients with LAST.

Survival and Factors Associated with Survival with Extracorporeal Life Support During Cardiac Arrest: A Systematic Review and Meta-Analysis

The survival rate after cardiac arrest (CA) remains low. The utilization of extracorporeal life support is proposed to improve management. However, this resource-intensive tool is associated with complications and must be used in selected patients. We performed a meta-analysis to determine predictive factors of survival. Among the 81 studies included, involving 9256 patients, survival was 26.2% at discharge and 20.4% with a good neurologic outcome. Meta-regressions identified an association between survival at discharge and lower lactate values, intrahospital CA, and lower cardio pulmonary resuscitation (CPR) duration. After adjustment for age, intrahospital CA, and mean CPR duration, an initial shockable rhythm was the only remaining factor associated with survival to discharge (β = 0.02, 95% CI: 0.007-0.02; p = 0.0004).

Atrial Fibrillation and Ischemic Stroke: A Clinical Review

Atrial fibrillation (AF) is an important risk factor for ischemic stroke resulting in a fivefold increased stroke risk and a twofold increased mortality. Our understanding of stroke mechanisms in AF has evolved since the concept of atrial cardiopathy was introduced as an underlying pathological change, with both AF and thromboembolism being common manifestations and outcomes. Despite the strong association with stroke, there is no evidence that screening for AF in asymptomatic patients improves clinical outcomes; however, there is strong evidence that patients with embolic stroke of undetermined source may require long-term monitoring to detect silent or paroxysmal AF. Stroke prevention in patients at risk, assessed by the CHA₂DS₂-VASc score, was traditionally achieved with warfarin; however, direct oral anticoagulants have solidified their role as safe and effective alternatives. Additionally, left atrial appendage exclusion has emerged as a viable option in patients intolerant of anticoagulation. When patients with AF have an acute stroke, the timing of initiation or resumption of anticoagulation for secondary stroke prevention has to be balanced against the risk of hemorrhagic conversion. Multiple randomized clinical trials are currently underway to determine the best timing for administration of anticoagulants following acute ischemic stroke.

Management of ST-Elevation Myocardial Infarction in High-Risk Settings

Despite the widespread adoption of primary percutaneous intervention and modern antithrombotic therapy, ST-segment elevation myocardial infarction (STEMI) remains the leading cause of death in the United States and remains one of the most important causes of morbidity and mortality worldwide. Certain high-risk patients present a challenge for diagnosis and treatment. The widespread adoption of primary percutaneous intervention in addition to modern antithrombotic therapy has resulted in substantial improvement in the short- and long-term prognosis following STEMI. In this review, we aim to provide a brief analysis of the state-of-the-art treatment for patients presenting with STEMI, focusing on cardiogenic shock, current treatment and controversies, cardiac arrest, and diagnosis and treatment of mechanical complications, as well as multivessel and left main-related STEMI.

Use of extracorporeal membrane oxygenation in high-risk acute pulmonary embolism: A systematic review and meta-analysis

Extracorporeal membrane oxygenation (ECMO) represents a therapeutic option for cardiopulmonary support in patients with high-risk pulmonary embolism (PE); however, no definite consensus exists on ECMO use in high-risk PE. Hence, we aim to provide insights into its real-world use pooling together all available published experiences. We performed a systematic review and pooled analysis of all published studies (up to April 17, 2020) investigating ECMO support in high-risk PE. All studies including at least four patients were collectively analyzed. Study outcomes were early all-cause death (primary endpoint) and relevant in-hospital adverse events. A total of 21 studies were included in the pooled analysis (n = 635 patients). In this population (mean age 47.8 ± 17.3 years, 44.5% females), ECMO was indicated for cardiac arrest in 62.3% and immediate ECMO support was pursued in 61.9% of patients. Adjunctive reperfusion therapies were implemented in 57.0% of patients. Pooled estimate rate of early all-cause mortality was 41.1% (95% CI 27.7%-54.5%). The most common in-hospital adverse event was major bleeding, with an estimated rate of 28.6% (95%CI 21.0%-36.3%). At meta-regression analyses, no significant impact of multiple covariates on the primary endpoint was found. In this systematic review of patients who received ECMO for high-risk PE, pooled all-cause mortality was 41.1%. Principal indication for ECMO was cardiac arrest, cannulation was chiefly performed at presentation, and major bleeding was the most common complication.

A retrospective analysis of inpatient cardiac arrests over one year at a tertiary heart attack and cardiothoracic centre identifying potential candidates for an inpatient extracorporeal cardiopulmonary resuscitation service

Introduction

Extracorporeal cardiopulmonary resuscitation (ECPR) is an internationally recognised treatment for refractory cardiac arrest, with evidence of improved outcomes in selected patient groups from cohort studies and case series. In order to establish the clinical need for an in-hospital extracorporeal cardiopulmonary resuscitation service at a tertiary cardiac centre, we analysed the inpatient cardiac arrest database for the previous 12 months.

Methods

Evidence-based inclusion criteria were used to retrospectively identify the number of patients potentially eligible for extracorporeal cardiopulmonary resuscitation over a 12-month period.

Results

A total of 261 inpatient cardiac arrests were analysed with 21 potential extracorporeal cardiopulmonary resuscitation candidates meeting the inclusion criteria (1.75 patients per month, or 8% of inpatient cardiac arrests (21/261)). The majority (71%) of these cardiac arrests occurred outside of normal working hours. Survival-to-discharge within this sub-group with conventional cardiopulmonary resuscitation was 19% (4/21).

Conclusion

Sufficient numbers of refractory inpatient cardiac arrests occur to justify an extracorporeal cardiopulmonary resuscitation service, but a 24-h on-site extracorporeal membrane oxygenation team presents a significant financial and logistical challenge.

Extracorporeal Life Support Increases Survival After Prolonged Ventricular Fibrillation Cardiac Arrest in the Rat

Background:

Extracorporeal life support (ECLS) for cardiopulmonary resuscitation (CPR) may increase end organ perfusion and thus survival when conventional CPR fails. The aim was to investigate, if after ventricular fibrillation cardiac arrest in rodents ECLS improves outcome compared with conventional CPR.

Methods:

In 24 adult male Sprague–Dawley rats (460–510 g) resuscitation was started after 10 min of no-flow with ECLS (consisting of an open reservoir, roller pump, and membrane oxygenator, connected to cannulas in the jugular vein and femoral artery, n = 8) or CPR (mechanical chest compressions plus ventilations, n = 8) and compared with a sham group (n = 8). After return of spontaneous circulation (ROSC), all rats were maintained at 33°C for 12 h. Survival to 14 days, neurologic deficit scores and overall performance categories were assessed.

Results:

ECLS leads to sustained ROSC in 8 of 8 (100%) and neurological intact survival to 14 days in 7 of 8 rats (88%), compared with 5 of 8 (63%) and 1 of 8 CPR rats. The median survival time was 14 days (IQR: 14–14) in the ECLS and 1 day (IQR: 0 to 5) for the CPR group (P = 0.004).

Conclusion:

In a rat model of prolonged ventricular fibrillation cardiac arrest, ECLS with mild hypothermia produces 100% resuscitability and 88% long-term survival, significantly better than conventional CPR.

Out of hospital extracorporeal life support (ECLS) implantation in cardiogenic shock after cardiac arrest

We report the use of out-of-hospital extracorporeal life support (ECLS) in a 62-year-old patient with severe cardiogenic shock after cardiac arrest. The patient was successfully stabilized using the ECLS system in the pre-hospital setting. Hospital discharge with a good neurological outcome was possible after 23days.

Pre-hospital extra-corporeal cardiopulmonary resuscitation

Survival from out-of-hospital cardiac arrest (OHCA) has remained low despite advances in resuscitation science. Hospital-based extra-corporeal cardiopulmonary resuscitation (ECPR) is a novel use of an established technology that provides greater blood flow and oxygen delivery during cardiac arrest than closed chest compressions. Hospital-based ECPR is currently offered to selected OHCA patients in specialized centres. The interval between collapse and restoration of circulation is inversely associated with good clinical outcomes after ECPR. Pre-hospital delivery of ECPR concurrent with conventional resuscitation is one approach to shortening this interval and improving outcomes after OHCA. This article examines the background and rationale for pre-hospital ECPR; summarises the findings of a literature search for published evidence; and considers candidate selection, logistics, and complications for this complex intervention.

New Therapeutic Concepts in Post-Resuscitation Care

After the return of spontaneous circulation (ROSC), as a result of global ischaemia due to cardiac arrest followed by reperfusion, a condition develops called post-cardiac arrest syndrome. It manifests, alongside the pathology that caused the cardiac arrest, as a systemic inflammatory response, including severe cardio-circulatory and neurological dysfunction, leading to a fatal outcome. Th e aim of post-resuscitation care is to reduce the consequences of circulatory arrest, reperfusion, and the inflammatory response of the body on vital organ functions. The basis of post-resuscitation care comprises application of therapeutic hypothermia and early coronary angiography with PCI. However, after the initial enthusiasm, the validity of applying these aggressive methods in all comatose post-cardiac arrest patients was questioned. Currently, instead of therapeutic hypothermia, a strategy of maintaining a targeted body temperature, usually 36 °C, is being applied because there is no clear evidence of benefit for maintaining a lower body temperature in relation to the outcome. Additionally, patients with an obvious cardiac aetiology of cardiac arrest do not undergo early coronarography unless there is a clear indication of coronary artery occlusion. In the post-resuscitation period, the maintenance of adequate ventilation, maintaining levels of oxygen and carbon dioxide in the normal range, haemodynamic stability, control of blood glucose and electrolytes, and epileptic attack prevention are all strongly recommended measures. Th ere is no evidence to suggest that the application of the so-called neuroprotective agents affects the outcome of cardiac arrest.

[Technical assist devices : Perspectives and new developments]

The development of technical assist devices in the context of cardiopulmonary resuscitation (CPR) reaches back to the early roots of modern resuscitation research. This article covers the subjects of extracorporeal CPR (ECPR), including extracorporeal life support (ECLS), emergency ECLS (EECLS) and mechanical resuscitation devices. Specifically, the potential use of active compression-decompression CPR (ACD-CPR), impedance threshold devices (ITD) and capnography as additional measures during resuscitation are described in detail. Furthermore, the article presents a compact preview of the potential future developments of technical aids in the field of life support and postresuscitation care.

Extracorporeal cardiopulmonary resuscitation for refractory cardiac arrest in children after cardiac surgery

OBJECTIVE

Extracorporeal membrane oxygenation (ECMO) is used to provide cardiorespiratory support during cardiopulmonary resuscitation (extracorporeal cardiopulmonary resuscitation; ECPR) unresponsive to conventional methods. In this study, the results of ECPR in a cardiac arrest setting after cardiac surgery in children were analyzed.

METHODS

In this retrospective cohort study, between November 2010 and June 2014, 613 congenital heart operations were performed by the same surgical team. Medical records of all the patients who experienced cardiac arrest and ECPR in an early postoperative period (n=25; 4%) were analyzed. Their ages were between 2 days and 4.5 years (median: 3 months). Sixteen patients had palliative procedures. In 88% of the patients, cardiac arrest episodes occurred in the first 24 h after operation. Mechanical support was provided by cardiopulmonary bypass only (n=10) or by ECMO (n=15) during CPR.

RESULTS

The CPR duration until commencing mechanical support was <20 min in two patients, 20-40 min in 11 patients, and >40 min in 12 patients. Eleven patients (44%) were weaned successfully from ECMO and survived more than 7 days. Five of them (20%) could be discharged. The CPR duration before ECMO (p=0.01) and biventricular physiology (p=0.022) was the key factor affecting survival. The follow-up duration was a mean of 15±11.9 months. While four patients were observed to have normal neuromotor development, one patient died of cerebral bleeding 6 months after discharge.

CONCLUSION

Postoperative cardiac arrest usually occurs in the first 24 h after operation. ECPR provides a second chance for survival in children who have had cardiac arrest. Shortening the duration of CPR before ECMO might increase survival rates.

Protocols for uncontrolled donation after circulatory death: a systematic review of international guidelines, practices and transplant outcomes

INTRODUCTION

A chronic shortage of organs remains the main factor limiting organ transplantation. Many countries have explored the option of uncontrolled donation after circulatory death (uDCD) in order to expand the donor pool. Little is known regarding the variability of practices and outcomes between existing protocols. This systematic review addresses this knowledge gap informing policy makers, researchers, and clinicians for future protocol implementation.

METHODS

We searched MEDLINE, EMBASE, and Google Scholar electronic databases from 2005 to March 2015 as well as the reference lists of selected studies, abstracts, unpublished reports, personal libraries, professional organization reports, and government agency statements on uDCD. We contacted leading authors and organizations to request their protocols and guidelines. Two reviewers extracted main variables. In studies reporting transplant outcomes, we added type, quantity, quality of organs procured, and complications reported. Internal validity and the quality of the studies reporting outcomes were assessed, as were the methodological rigour and transparency in which a guideline was developed. The review was included in the international prospective register of systematic reviews (Prospero, CRD42014015258).

RESULTS

Six guidelines and 18 outcome studies were analysed. The six guidelines are based on limited evidence and major differences exist between them at each step of the uDCD process. The outcome studies report good results for kidney, liver, and lung transplantation with high discard rates for livers.

CONCLUSIONS

Despite procedural, medical, economic, legal, and ethical challenges, the uDCD strategy is a viable option for increasing the organ donation pool. Variations in practice and heterogeneity of outcomes preclude a meta-analysis and prevented the linking of outcomes to specific uDCD protocols. Further standardization of protocols and outcomes is required, as is further research into the role of extracorporeal resuscitation and other novel therapies for treatment of some refractory cardiac arrest. It is essential to ensure the maintenance of trust in uDCD programs by health professionals and the public.

[Veno-arterial extracorporeal membrane oxygenation. Indications, limitations and practical implementation]

Due to the technical advances in pumps, oxygenators and cannulas, veno-arterial extracorporeal membrane oxygenation (va-ECMO) or extracorporeal life support (ECLS) has been widely used in emergency medicine and intensive care medicine for several years. An accepted indication is peri-interventional cardiac failure in cardiac surgery (postcardiotomy low cardiac output syndrome). Furthermore, especially the use of va-ECMO for other indications in critical care medicine, such as in patients with severe sepsis with septic cardiomyopathy or in cardiopulmonary resuscitation has tremendously increased. The basic indications for va-ECMO are therapy refractory cardiac or cardiopulmonary failure. The fundamental purpose of va-ECMO is bridging the function of the lungs and/or the heart. Consequently, this support system does not represent a causal therapy by itself; however, it provides enough time for the affected organ to recover (bridge to recovery) or for the decision for a long-lasting organ substitution by a ventricular assist device or by transplantation (bridge to decision). Although the outcome for bridged patients seems to be favorable, it should not be forgotten that the support system represents an invasive procedure with potentially far-reaching complications. Therefore, the initiation of these systems needs a professional and experienced (interdisciplinary) team, sufficient resources and an individual approach balancing the risks and benefits. This review gives an overview of the indications, complications and contraindications for va-ECMO. It discusses its advantages in organ transplantation and transport of critically ill patients. The reader will learn the differences between peripheral and central cannulation and how to monitor and manage va-ECMO.

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.

Full neurologic recovery and return of spontaneous circulation following prolonged cardiac arrest facilitated by percutaneous left ventricular assist device

Sudden cardiac arrest is associated with high early mortality, which is largely related to postcardiac arrest syndrome characterized by an acute but often transient decrease in left ventricular (LV) function. The stunned LV provides poor cardiac output, which compounds the initial global insult from hypoperfusion. If employed early, an LV assist device (LVAD) may improve survival and neurologic outcome; however, traditional methods of augmenting LV function have significant drawbacks, limiting their usefulness in the periarrest period. Full cardiac support with cardiopulmonary bypass is not always readily available but is increasingly being studied as a tool to intensify resuscitation. There have been no controlled trials studying the early use of percutaneous LVADs (pLVADs) in pericardiac arrest patients or intra-arrest as a bridge to return of spontaneous circulation. This article presents a case study and discussion of a patient who arrested while undergoing an elective coronary angioplasty and suffered prolonged cardiopulmonary resuscitation. During resuscitation, treatment included placement of a pLVAD and initiation of therapeutic hypothermia. The patient made a rapid and full recovery.