Induced hypothermia following out-of-hospital cardiac arrest; initial experience in a community hospital

BACKGROUND: Successful resuscitation from sudden cardiac death is frequently accompanied by severe and often fatal neurologic injury. Induced hypothermia (IH) may attenuate the neurologic damage observed in patients after cardiac arrest. HYPOTHESIS: This study examined a population of nonselected patients presenting to a community hospital following successful resuscitation of sudden cardiac death. We sought to determine whether a program of induced hypothermia would improve the clinical outcome of these critically ill patients. METHODS: We initiated a protocol of IH at the Oklahoma Heart Hospital in August of 2003. Study patients were consecutive adults admitted following successful resuscitation of out-of-hospital cardiac arrest. Moderate hypothermia was induced by surface cooling and maintained for 24 to 36 h in the Intensive Care Unit with passive rewarming over 8 h. RESULTS: Forty-nine patients who were resuscitated and had the return of spontaneous circulation completed the hypothermia protocol. The cause of cardiac arrest was acute myocardial infarction in 24 patients and cardiac arrhythmias in 19 patients. Nineteen patients (39%) survived and were discharged. Sixteen of the patients discharged had no or minimal residual neurologic dysfunction and 3 patients had clinically significant residual neurologic injury. CONCLUSION: A program of induced hypothermia based in a community hospital is feasible, practical, and requires limited additional financial and nursing resources. Survival and neurologic recovery compare favorably with clinical trial outcomes.     

Systematic review of the incidence of sudden cardiac death in the United States

The need for consistent and current data describing the true incidence of sudden cardiac arrest (SCA) and/or sudden cardiac death (SCD) was highlighted during the most recent Sudden Cardiac Arrest Thought Leadership Alliance's (SCATLA) Think Tank meeting of national experts with broad representation of key stakeholders, including thought leaders and representatives from the American College of Cardiology, American Heart Association, and the Heart Rhythm Society. As such, to evaluate the true magnitude of this public health problem, we performed a systematic literature search in MEDLINE using the MeSH headings, "death, sudden" OR the terms "sudden cardiac death" OR "sudden cardiac arrest" OR "cardiac arrest" OR "cardiac death" OR "sudden death" OR "arrhythmic death." Study selection criteria included peer-reviewed publications of primary data used to estimate SCD incidence in the U.S. We used Web of Science's Cited Reference Search to evaluate the impact of each primary estimate on the medical literature by determining the number of times each "primary source" has been cited. The estimated U.S. annual incidence of SCD varied widely from 180,000 to >450,000 among 6 included studies. These different estimates were in part due to different data sources (with data age ranging from 1980 to 2007), definitions of SCD, case ascertainment criteria, methods of estimation/extrapolation, and sources of case ascertainment. The true incidence of SCA and/or SCD in the U.S. remains unclear, with a wide range in the available estimates that are badly dated. As reliable estimates of SCD incidence are important for improving risk stratification and prevention, future efforts are clearly needed to establish uniform definitions of SCA and SCD and then to prospectively and precisely capture cases of SCA and SCD in the overall U.S. population.     

Different forms of bystander cardiopulmonary resuscitation in out-of-hospital cardiac arrest

Out-of-hospital cardiac arrest (OHCA) is a major cause of death in the Western world with an estimated number of 275 000 treated with resuscitation attempts by the Emergency Medical Services (EMS) in Europe each year. Overall survival rates remain low, and most studies indicate that around 1 out 10 will survive to 30 days. Amongst the strongest factors associated with survival in OHCA is first recorded rhythm amendable to defibrillation, early defibrillation and prompt initiation of cardiopulmonary resuscitation (CPR). Overall, CPR started prior to EMS arrival has repeatedly been shown to be associated with survival rates 2–3 times higher compared with no such initiation. The primary goal of CPR is to generate sufficient blood flow to vital organs, mainly the brain and heart, until restoration of spontaneous circulation can be achieved. Barriers to the initiation of CPR by bystanders in OHCA include fear of being incapable, causing harm, and transmission of infectious diseases. Partly due to these barriers, and low rates of CPR, the concept of CPR with compression only was proposed as a simpler form of resuscitation with the aim to be more widely accepted by the public in the 1990s. But how reliable is the evidence supporting this simpler form of CPR, and are the outcomes after CO-CPR comparable to standard CPR?     

Clinical and genetic evaluation after sudden cardiac arrest

Sudden cardiac arrest (SCA) and sudden cardiac death (SCD) can be attributed to cardiac, respiratory, metabolic, and toxicologic etiologies. Most cases of SCD are caused by coronary artery disease and approximately 40% of cardiac arrests are unexplained. Inherited arrythmias and cardiomyopathies are important contributors to SCA and SCD. Identifying an inherited condition after such an event not only has important ramifications for the individual, but also for relatives who may be at risk for the familial condition. This review will provide an overview of inherited cardiovascular disorders than can predispose to SCA/SCD, review the diagnostic evaluation for an individual and/or family after an SCA/SCD, and discuss the role of genetic testing.     

Community-level socioeconomic status and outcomes of patients with out-of-hospital cardiac arrest: A systematic review and meta analysis

Background:The aim of this systematic review and meta-analysis was to investigate the associations of community-level socioeconomic status (SES) on outcomes of patients with out-of hospital cardiac arrest (OHCA).Methods:A systematic literature review was conducted using PubMed, EMBASE, and the Cochrane database according to guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We included literature that presented the outcomes based on community-level SES among patients with OHCA. SES indicators included economic indicators such as income, wealth, and occupation, as well as combined indicators, where any of these indicators were integrated. Outcomes were bystander cardiopulmonary resuscitation (CPR) and survival to discharge.Results:From 1394 titles, 10 cross-sectional observational studies fulfilled inclusion and exclusion criteria, representing 118,942 patients with OHCA. The odds ratios (ORs) of bystander CPR and survival to discharge for lower community-level SES patients were lower than those for higher community-level SES by economic SES indicators (bystander CPR OR 0.67; 95% CI 0.51–0.89, survival to discharge OR 0.60; 95% CI 0.35–1.02). Based on combined SES indicators the results showed similar patterns (bystander CPR OR 0.80; 95% CI 0.75–0.84, survival to discharge OR 0.76; 95% CI 0.63–0.92).Conclusion:In this meta-analysis, community-level SES was significantly associated with bystander CPR and survival among patients with OHCA.     

Advanced cardiac life support: Update on recent guidelines and a look at the future

The objectives of this article are to provide an update of the American Heart Association (AHA) 1992 National Conference guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiac care and to review the investigation and development of new methods of CPR which may be considered in future recommendations. Despite an organized approach to sudden cardiac arrest, survival in patients receiving CPR is in the range of 5–15%. The new AHA guidelines recommend standard manual CPR performed at a rate of 80–100 compressions/min and organized algorithms of advanced cardiac life support. These guidelines stress widespread community training and rapid response in the following sequence: (1) recognition of early warning signs, (2) activation of the emergency medical system (EMS), (3) basic CPR, (4) early defibrillation, (5) intubation, and (6) intravenous medication. Several new recommendations pertain specifically to in-hospital care and are, therefore, particularly relevant to physician management of cardiac arrest. The best predictor of survival in patients requiring circulatory support after cardiac arrest is attainable coronary and cerebral perfusion. Unfortunately, the minimal levels of end-organ perfusion required to sustain life are often difficult or impossible to achieve with standard manual cardiopulmonary resuscitation and several new techniques have therefore been introduced. The most promising of these techniques are (1) interposed abdominal compression, (2) pneumatic vest, and (3) active compression-decompression resuscitation. Each of these techniques offers unique advantages when compared with standard manual cardiopulmonary resuscitation. The 1992 National Conference recommendations provide a rational framework for the resuscitation of cardiac arrest victims. New methods of cardiopulmonary resuscitation are now available and investigation into these methods continues. In the future, these modalities may be incorporated in newer guidelines and be available on a widespread basis to supplement our current approach to cardiac arrest.     

Assessing the risk of sudden cardiac death

Detection of a major risk factor for sudden death in an otherwise asymptomatic person often raises major difficulties in management, particularly where the only treatment available is invasive, such as the implantable defibrillator. Recent guidelines have described the appropriate use of this technology, but often difficulty remains. This is particularly the case where the condition is newly recognised and its natural history not yet extensively described. A 63 year old man, whose condition was diagnosed as Brugada syndrome, in whom this problem is illustrated is described.


Keywords: Brugada syndrome; sudden cardiac death     

Gender difference in the clinical outcomes of patients with out-of-hospital cardiac arrest: A report using data from a national Korean registry

We explored gender differences in the characteristics and outcomes of patients with out-of-hospital cardiac arrest (OHCA) in Korea.We retrospectively analyzed a nationwide multicenter registry of out-of-hospital cardiac arrest patients that prospectively collected from January to December 2014, and explored the clinical outcomes of 670 successfully resuscitated adult patients with OHCA who were transferred to 27 hospitals. The effect of gender on the 30-day neurologically favorable survival (cerebral performance category 1 or 2) was analyzed after propensity score matching (PSM) of each patient in terms of clinical characteristics.We included 670 patients with OHCA, of whom 482 (72%) were male and 182 (28%) were female. The frequency of witnessed arrests and proportion of home arrests were similar between men and women (73.7% vs 71.3%, P = .59, and 55.0% vs 60.6% P = .21, respectively). Women were older than men (mean age, 65.9 vs 59.7 years, P < .001) and less likely to present with an initial shockable rhythm (27.7% vs 45.0%, P < .001). Women were less likely to undergo targeted temperature management (19.1% vs 35.9%, P < .001), coronary angiography (14.9% vs 36.1%, P < .001), or revascularization (7.4% vs 19.3%, P < .001). Compared with men, women exhibited poorer 30-day neurologically favorable survival (69.7% vs 83.0%, P = .001). However, the gender difference was not significant on PSM or inverse probability of treatment weighting (IPTW) analyses (P = .48 and P = .63, respectively).Female patients with OHCA exhibited poorer clinical characteristics and were less likely to receive treatment than men. After accounting for these differences, clinical outcomes did not differ by gender.     

Analysis of ambulatory electrocardiograms in 14 patients who experienced sudden cardiac death during monitoring

The Holter monitors of 14 patients (out of 58,000 Holter recordings performed between 1978 and 1984) who experienced cardiac arrest and expired during the recording period were analyzed. Tachyarrhythmic arrest patients frequently had coronary heart disease, congestive heart failure, and prolonged QTc intervals. The highest incidence of intermediately frequent premature ventricular complexes (PVCs) occurred between 15 and 6 hours prior to death. The frequency of ventricular couplets increased toward the time of arrest. The hours with greatest frequency of ventricular tachycardia (VT) were found to be the last 5 hours of life. An increasing incidence of ST-segment changes greater than 2 mm was noted throughout all of the risk periods until the third hour prior to arrest when the incidence diminished. Conversely, the incidence of lower amplitude ST-segment changes (usually elevation) increased over the final 6 hours. The mean time of death was 0228 hours +/- 5:20. In conclusion, we observed two patterns of Holter-monitored changes which usually occurred prior to death and may represent predictors of sudden death: (1) an increasing incidence of intermediately frequent isolated PVCs followed by increased ventricular couplets and runs of VT; (2) return of high amplitude ST-segment changes toward baseline. To our knowledge, the temporal relationship of the degree of ST-segment deviation to sudden death and the time of sudden death have not been reported in large studies of Holter-monitored sudden death patients.     

新旧心肺复苏指南指导院外心源性猝死抢救效果的对比研究

目的：比较2005年旧版心肺复苏（CPR）指南和2010年新版CPR指南指导下院外心源性猝死（SCA）的抢救效果。方法纳入2008年7月~2010年9月在旧版CRP指导下进行院外CRP抢救的SCA患者248例作为旧指南组,2011年1月~2013年3月在新版CRP指导下抢救的SCA患者282例作为新指南组,比较两组SCA患者经CPR抢救后的自主循环恢复率、1个月存活率以及1个月后无脑功能受损的存活率。结果与旧指南组比较,新指南组自主循环恢复率明显增加（12.77%vs.7.66%,P=0.045）,其中SCA发作至接受CPR的时间≤10 min的患者中,新指南组自主循环恢复率明显高于旧指南组（36.23%vs.19.35%, P=0.032）;而超过10 min接受CPR的患者之间自主循环恢复率无差异（5.16%vs.3.76%,P=0.501）。新指南组1个月后存活率以及存活且无脑功能受损的患者比例均高于旧指南组,但差异均无统计学意义（P＞0.05）。结论新版CPR指南较旧版指南抢救SCA患者成功率更高,同时还可提高患者无脑功能受损的存活率。     

心脏复极异常和心脏性猝死

心脏性猝死（sudden cardiac death,SCD）是主要的猝死原因之一,具有无预兆、进展快的特点,因此识别 SCD 高风险患者具有极大的临床价值。随着研究的深入,心脏复极异常与 SCD 的关系逐渐被揭示出来。本文就心脏复极异常的表现与 SCD 的联系以及机制加以简要概述。     

Heartstart Scotland: the use of paramedic skills in out of hospital resuscitation

Objective—To assess the frequency with which paramedic skills were used in out of hospital cardiac arrest and the effect of tracheal intubation on outcome.
Design—Retrospective analysis of ambulance service reports and hospital records.
Setting—Scottish Ambulance Service and hospitals admitting acute patients throughout Scotland.
Results—A total of 8651 out of hospital resuscitation attempts were recorded and tracheal intubation was attempted in 3427 (39.6%) arrests. One hundred and thirty six patients (3.7%) were intubated and 476 (9.1%) of the patients who were not intubated survived to hospital discharge (p < 0.001). Among the patients who were defibrillated the proportion intubated was highest in the patients who received the greatest number of shocks (p < 0.01). Among subjects receiving similar numbers of shocks survival rates were lower for intubated patients (p < 0.01). Patients with unwitnessed arrests were most frequently intubated and survival rates were lowest in this group.
Conclusions—Patients who are intubated seem to have lower survival rates. This may however reflect the difficulty of the resuscitation attempt rather than the effects of intubation. The use of basic life support skills rapidly after cardiac arrest is associated with the best survival rates.

Keywords: paramedics;  resuscitation;  myocardial infarction;  tracheal intubation;  prehospital care     

Transvenous versus subcutaneous implantable cardioverter defibrillators in young cardiac arrest survivors

Secondary prevention implantable cardioverter defibrillators (ICDs) are indicated in young patients presenting with aborted sudden cardiac death (SCD) because of ventricular arrhythmias. Transvenous-ICDs (TV-ICDs) are effective, established therapies supported by evidence. The significant morbidity associated with transvenous leads led to the development of the newer subcutaneous-ICD (S-ICD). This review discusses the clinical considerations when selecting an ICD for the young patient presenting with out-of-hospital cardiac arrest. The major benefits of TV-ICDs are their ability to pace (antitachycardia pacing [ATP], bradycardia support and cardiac resynchronisation therapy [CRT]) and the robust evidence base supporting their use. Other benefits include a longer battery life. Significant complications associated with transvenous leads include pneumothorax and tamponade during insertion and infection and lead failure in the long term. Comparatively, S-ICDs, by virtue of having no intravascular leads, prevent these complications. S-ICDs have been associated with a higher incidence of inappropriate shocks. Patients with an indication for bradycardia pacing, CRT or ATP (documented ventricular tachycardia) are seen as unsuitable for a S-ICD. If venous access is unsuitable or undesirable, S-ICDs should be considered given the patient is appropriately screened. There is a need for further randomised controlled trials to directly compare the two devices. TV-ICDs are an effective therapy for preventing SCD limited by significant lead-related complications. S-ICDs are an important development hindered largely by an inability to pace. Young patients stand to gain the most from a S-ICD as the cumulative risk of lead-related complications is high. A clinical framework to aid decision-making is presented.     

Factors modifying the effect of bystander cardiopulmonary resuscitation on survival in out-of-hospital cardiac arrest patients in Sweden.

AIM: To describe possible factors modifying the effect of bystander cardiopulmonary resuscitation on survival among patients suffering an out-of-hospital cardiac arrest. PATIENTS: A national survey in Sweden among patients suffering out-of-hospital cardiac arrest and in whom resuscitative efforts were attempted. Sixty per cent of ambulance organizations were included. DESIGN: Prospective evaluation. Survival was defined as survival 1 month after cardiac arrest. RESULTS: In all, 14065 reports were included in the evaluation. Of these, resuscitation efforts were attempted in 10966 cases, of which 1089 were witnessed by ambulance crews. The report deals with the remaining 9877 patients, of whom bystander cardiopulmonary resuscitation was attempted in 36%. Survival to 1 month was 8.2% among patients who received bystander cardiopulmonary resuscitation vs 2.5% among patients who did not receive it (odds ratio 3.5, 95% confidence interval 2.9-4.3). The effect of bystander cardiopulmonary resuscitation on survival was related to: (1) the interval between collapse and the start of bystander cardiopulmonary resuscitation (effect more marked in patients who experienced a short delay); (2) the quality of bystander cardiopulmonary resuscitation (effect more marked if both chest compressions and ventilation were performed than if either of them was performed alone); (3) the category of bystander (effect more marked if bystander cardiopulmonary resuscitation was performed by a non-layperson); (4) interval between collapse and arrival of the ambulance (effect more marked if this interval was prolonged); (5) age (effect more marked in bystander cardiopulmonary resuscitation among the elderly); and (6) the location of the arrest (effect more marked if the arrest took place outside the home). CONCLUSION: The effect of bystander cardiopulmonary resuscitation on survival after an out-of-hospital cardiac arrest can be modified by various factors. Factors that were associated with the effect of bystander cardiopulmonary resuscitation were the interval between the collapse and the start of bystander cardiopulmonary resuscitation, the quality of bystander cardiopulmonary resuscitation, whether or not the bystander was a layperson, the interval between collapse and the arrival of the ambulance, age and the place of arrest.     

Five-year survival of patients after out-of-hospital cardiac arrest depending on age

Patient's age belongs to the independent prognostic factors of patients after out-of-hospital cardiac arrest (OHCA). This study aimed to evaluate the influence of age on 5-year survival in professionally cardio-pulmonary resuscitated patients with “primary cardiac” etiology OHCA. In this analysis of prospective multi-centric study, from April 1, 2002 until August 31, 2004, a total of 560 patients were included (aged 16-97 years) from the East Bohemian region, for whom a professional cardio-pulmonary resuscitation for OHCA was attempted. In the age subgroup <70 years there were 307 patients and in the age subgroup ≥70 years there were 253 patients. Of the subgroup <70 years, 29 patients (10%) survived to year 5 (58% from the 50 patients surviving to day 30), and in the subgroup ≥70 years, we had 4 patients surviving to year 5 (2%) (29% from the 14 patients surviving to day 30), respectively (Fisher‘s exact test; comparison in the all resuscitated patients: p < 0.001, in the population surviving to day 30: p = 0.071). In conclusion, there was a trend towards a worse outcome in 5-year survival following OHCA in the patients aged ≥70 years. Nevertheless, these data support that prognosis OHCA of elders is not associated with universal dismal outcome.