Pediatric resuscitation and cardiac arrest

Cardiac arrest in children is, fortunately, a relatively infrequent event. Mortality rate after cardiac arrest is greater than 50%. This article discusses strategies to increase the chance of survival to discharge. These strategies focus on suggestions for organizing a system prepared to care for critically ill children, incorporating the 2010 American Heart Association resuscitation guidelines into clinical practice, and encouraging physicians to become advocates of decreasing the occurrence of pediatric cardiac arrest. Providing the best-prepared system available to care for critically ill children will, it is hoped, decrease the number of preventable deaths in children.     

Emergency Department inter-hospital transfer for post-cardiac arrest care: Initial experience with implementation of a regional cardiac resuscitation center in the United States

Objective

The American Heart Association recently recommended regional cardiac resuscitation centers (CRCs) for post-resuscitation care following out-of-hospital cardiac arrest (OHCA). Our objective was to describe initial experience with CRC implementation.

Methods

Prospective observational study of consecutive post-resuscitation patients transferred from community Emergency Departments (EDs) to a CRC over 9 months. Transfer criteria were: OHCA, return of spontaneous circulation (ROSC), and comatose after ROSC. Incoming patients were received and stabilized in the ED of the CRC where advanced therapeutic hypothermia (TH) modalities were applied. Standardized post-resuscitation care included: ED evaluation for cardiac catheterization, TH (33–34 °C) for 24 h, 24 h/day critical care physician support, and evidence-based neurological prognostication. Prospective data collection utilized the Utstein template. The primary outcome was survival to hospital discharge with good neurological function [Cerebral Performance Category 1 or 2].

Results

Twenty-seven patients transferred from 11 different hospitals were included. The majority (21/27 [78%]) had arrest characteristics suggesting poor prognosis for survival (i.e. asystole/pulseless electrical activity initial rhythm, absence of bystander cardiopulmonary resuscitation, or an unwitnessed cardiac arrest). The median (IQR) time from transfer initiation to reaching TH target temperature was 7 (5–13) h. Ten (37%) patients survived to hospital discharge, and of these 9/10 (90% of survivors, 33% of all patients) had good neurological function.

Conclusions

Despite a high proportion of patients with cardiac arrest characteristics suggesting poor prognosis for survival, we found that one-third of CRC transfers survived with good neurological function. Further research to determine if regional CRCs improve outcomes after cardiac arrest is warranted.     

Therapeutic hypothermia after cardiac arrest: A retrospective comparison of surface and endovascular cooling techniques

Objectives

Therapeutic hypothermia (32-34 °C) is recommended for comatose survivors of cardiac arrest; however, the optimal technique for cooling is unknown. We aimed to compare therapeutic hypothermia using either surface or endovascular techniques in terms of efficacy, complications and outcome.

Design

Retrospective cohort study.

Setting

Thirty-bed teaching hospital intensive care unit (ICU).

Patients

All patients (n = 83) undergoing therapeutic hypothermia following cardiac arrest over a 2.5-year period. The mean age was 61 ± 16 years; 88% of arrests occurred out of hospital, and 64% were ventricular fibrillation/tachycardia.

Interventions

Therapeutic hypothermia was initiated in the ICU using iced Hartmann's solution, followed by either surface (n = 41) or endovascular (n = 42) cooling; choice of technique was based upon endovascular device availability. The target temperature was 32-34 °C for 12-24 h, followed by rewarming at a rate of 0.25 °C h⁻¹.

Measurements and main results

Endovascular cooling provided a longer time within the target temperature range (p = 0.02), less temperature fluctuation (p = 0.003), better control during rewarming (0.04), and a lower 48-h temperature load (p = 0.008). Endovascular cooling also produced less cooling-associated complications in terms of both overcooling (p = 0.05) and failure to reach the target temperature (p = 0.04). After adjustment for known confounders, there were no differences in outcome between the groups in terms of ICU or hospital mortality, ventilator free days and neurological outcome.

Conclusion

Endovascular cooling provides better temperature management than surface cooling, as well as a more favorable complication profile. The equivalence in outcome suggested by this small study requires confirmation in a randomized trial.     

Perturbation of the endothelial glycocalyx in post cardiac arrest syndrome

Background

The prognosis of immediate survivors of cardiac arrest remains poor, as the majority of these patients develops an inflammatory disorder known as the post-cardiac arrest syndrome (PCAS). Recently, the endothelial glycocalyx has been shown to be a key modulator of vascular permeability and inflammation, but its role in PCAS remains unknown.

Methods

Plasma levels of the glycocalyx components syndecan-1, heparan sulfate and hyaluronic acid were measured in 25 patients after immediate survival of cardiac arrest during different phases of PCAS. Twelve hemodynamically stable patients with acute coronary syndrome served as controls.

Results

Cardiac arrest resulted in a significant increase in syndecan-1, heparan sulfate and hyaluronic acid levels compared to controls, indicating a shedding of the endothelial glycocalyx as a pathophysiological component of the post cardiac arrest syndrome. The time course differed between the individual glycocalyx components, with a higher increase of syndecan-1 in the early phase of PCAS (2.8-fold increase vs. controls) and a later peak of heparan sulfate (1.7-fold increase) and hyaluronic acid (2-fold increase) in the intermediate phase. Only the plasma levels of syndecan-1 correlated positively with the duration of CPR and negatively with the glycocalyx-protective protease inhibitor antithrombin III. Plasma levels of both syndecan-1 and heparan sulfate were higher in eventual non-survivors than in survivors of cardiac arrest.

Conclusion

Our data for the first time demonstrates a perturbation of the endothelial glycocalyx in immediate survivors of cardiac arrest and indicate a potential important role of this endothelial surface layer in the development of post-cardiac arrest syndrome.     

Treatment and outcome in post-resuscitation care after out-of-hospital cardiac arrest when a modern therapeutic approach was introduced

BACKGROUND: The outcome among patients who are hospitalised alive after out-of-hospital cardiac arrest is still relatively poor. At present, there are no clear guidelines specifying how they should be treated. The aim of this survey was to describe the outcome for initial survivors of out-of-hospital cardiac arrest when a more aggressive approach was applied. PATIENTS: All patients hospitalised alive after out-of-hospital cardiac arrest in the Municipality of G?teborg, Sweden, during a period of 20 months. RESULTS: Of all the patients in the municipality suffering an out-of-hospital cardiac arrest in whom cardiopulmonary resuscitation (CPR) was attempted (n=375), 85 patients (23%) were hospitalised alive and admitted to a hospital ward. Of them, 65% had a cardiac aetiology and 50% were found in ventricular fibrillation. In 32% of the patients, hypothermia was attempted, 28% underwent a coronary angiography and 21% had a mechanical revascularisation. In overall terms, 27 of the 85 patients who were brought alive to a hospital ward (32%) survived to 30 days after cardiac arrest. Survival was only moderately higher among patients treated with hypothermia versus not (37% versus 29%; NS), and it was markedly higher among those who had early coronary angiography versus not (67% versus 18%; p<0.0001). CONCLUSION: In an era in which a more aggressive attitude was applied in post-resuscitation care, we found that the survival (32%) was similar to that in previous surveys. However, early coronary angiography was associated with a marked increase in survival and might be of benefit to many of these patients. Larger registries are important to further confirm the value of hypothermia in representative patient populations.     

Out-of-hospital cardiac arrest

Myocardial disease and death from cardiac arrest remain significant public health problems. Sudden death events and out-of-hospital cardiac arrests (OHCA) are encountered frequently by emergency medical services. Despite more than 30 years of research, survival rates remain extremely low. This article reviews access and presentations, demographics, OHCA outcomes, and response systems and processes in treatment of patients with arrest in this setting.     

Hypocalcemia following resuscitation from cardiac arrest revisited

Objective

Hypocalcemia associated with cardiac arrest has been reported. However, mechanistic hypotheses for the decrease in ionized calcium (iCa) vary and its importance unknown. The objective of this study was to assess the relationships of iCa, pH, base excess (BE), and lactate in two porcine cardiac arrest models, and to determine the effect of exogenous calcium administration on post-resuscitation hemodynamics.

Methods

Swine were instrumented and VF was induced either electrically (EVF, n = 65) or spontaneously, ischemically induced (IVF) with balloon occlusion of the LAD (n = 37). Animals were resuscitated after 7 min of VF. BE, iCa, and pH, were determined prearrest and at 15, 30, 60, 90, 120 min after ROSC. Lactate was also measured in 26 animals in the EVF group. Twelve EVF animals were randomized to receive 1 g of CaCl₂ infused over 20 min after ROSC or normal saline.

Results

iCa, BE, and pH declined significantly over the 60 min following ROSC, regardless of VF type, with the lowest levels observed at the nadir of left ventricular stroke work post-resuscitation. Lactate was strongly correlated with BE (r = −0.89, p < 0.0001) and iCa (r = −0.40, p < 0.0001). In a multivariate generalized linear mixed model, iCa was 0.005 mg/dL higher for every one unit increase in BE (95% CI 0.003-0.007, p < 0.0001), while controlling for type of induced VF. While there was a univariate correlation between iCa and BE, when BE was included in the regression analysis with lactate, only lactate showed a statistically significant relationship with iCa (p = 0.02). Post-resuscitation CaCl₂ infusion improved post-ROSC hemodynamics when compared to saline infusion (LV stroke work control 8 ± 5 g m vs 23 ± 4, p = 0.014, at 30 min) with no significant difference in tau between groups.

Conclusions

Ionized hypocalcemia occurs following ROSC. CaCl₂ improves post-ROSC hemodynamics suggesting that hypocalcemia may play a role in early post-resuscitation myocardial dysfunction.     

Inconsistencies in cardiac arrest reporting

Data relating to survival from in-hospital cardiac arrest are used to audit staff performance and to help to determine whether new resuscitation techniques are effective. Individual studies into outcome from cardiac arrest have defined inclusion and exclusion criteria, but no such national criteria have been published to enable constant auditing of cardiac arrests. The aim of this survey was to investigate the consistency with which in-hospital cardiac arrests are recorded throughout the United Kingdom. Such data are, almost universally, collected by Resuscitation Officers (RO). A questionnaire was sent to ROs across the UK asking them to state how they would interpret and categorise hypothetical, but nonetheless typical, clinical situations involving a cardiac arrest team being called. These included an event where the patient had regained consciousness prior to the arrival of the cardiac team and also an event where rigor mortis was already present and the resuscitation promptly abandoned upon the arrival of the cardiac arrest team. The percentage survival to discharge of adult cardiac arrests for each hospital was also requested. This identified whether inclusion or exclusion of certain clinical events may have influenced cardiac arrest survival figures for that hospital. It is clear from this study that in-hospital clinical events when a cardiac arrest team is called are audited with a great deal of inconsistency. Some events, such as a patient who has rigor mortis, are excluded as a false or inappropriate call in some hospitals and included as an unsuccessful resuscitation in others. There is a need for guidance on the inclusion and exclusion criteria for auditing of cardiac arrests so that meaningful data can be obtained from across the UK and useful conclusions drawn. The situation at present will result in data being audited that are of limited use. In the era of evidence-based medicine, it seems vital to obtain accurate cardiac arrest survival figures in order to have any hope of improving them.     

255例院前心搏骤停患者心肺复苏影响因素分析

目的了解6年来心肺复苏(CPR)现状,分析其影响因素,研究如何提高CPR水平。方法对本院2001-01～2007-01院前发生的255例心搏骤停(cardiacarrest,CA)患者的资料进行分析,比较自主循环恢复(ROSC)成功组和失败组的CPR开始时间、CPR持续时间、除颤次数、肾上腺素用量等。结果全部病例ROSC成功率为38.03%,脑复苏成功率仅为2.74%。两组CPR开始时间(从心脏停搏至CPR开始时间)、人工气道开始建立时间、是否安装临时起搏器、肾上腺素用量比较差异有统计学意义(P≤0.01),在CPR持续时间、除颤次数方面比较差异无统计学意义(P>0.05)。CPR成功率与CPR开始时间和急救水平高低有密切关系。结论CA患者CPR成功率较低,与"生命链"未彻底落实及急救水平低有关。普及全民急救知识,加强完善急救医疗体系建设,是提高CPR成功率的关键措施。     

Predictors of early care withdrawal following out-of-hospital cardiac arrest

Aims

To identify factors that associated with early care withdrawal in out-of-hospital cardiac arrest patients.

Methods

Data was collected from 189 survivors to hospital admission. Patients were classified by survival status upon hospital discharge, and those who died were categorized into withdrawal vs. no withdrawal of care. Those who had care withdrawn were further subdivided into early care withdrawal i.e. ≤72 h vs. late withdrawal >72 h. Multivariable adjusted odds ratios were used to assess factors associated with early care withdrawal.

Results

Of 189 patients with cardiac arrest, only 36 had advanced directives (19%) and 99 (52%) had care withdrawn. Most patients whose care was withdrawn died in hospital (94/99, 95%), and the remainder died in hospice. Care was withdrawn early ≤72 h in the majority of patients (59/94, 63%). Median time to early care withdrawal was 2 days IQR (1–3). Factors associated with early care withdrawal were age ≥75 years, poor initial neurologic exam, multiple co morbidities, multi-organ failure, lactic acid ≥10 mmol L⁻¹, Caucasian race and absence of bystander CPR. Advance directives did not appear to determine early care withdrawal.

Conclusions

Although most cardiac arrest patients do not have advance directives, care is often withdrawn in more than 50% and in many before the accepted time for neurological awakening (72 h). The decision to withdraw care is influenced by older age, race, preexisting co morbidities, multi-organ failure, and a poor initial neurological exam. Further studies are needed to better understand this phenomenon and other sociological factors that guide such decisions.     

氨茶碱和肾上腺素对大鼠心脏停搏的作用

目的探讨不同剂量氨茶碱和肾上腺素在大鼠窒息致心脏停搏模型中的疗效。方法呼气末夹闭气管8min,建立大鼠心脏停搏模型。48只大鼠随机分为氨茶碱和肾上腺素组,比较两组大鼠不同剂量的复苏疗效。结果心电活动恢复率氨茶碱组与肾上腺素组相比,差异无显著性(P>0.05);两组自主循环差异无显著性(P>0.05)。氨茶碱和肾上腺素复苏疗效均与剂量呈正相关。肾上腺素组心脏硬度记分显著高于氨茶碱组,且剂量越大,心脏硬度记分越高。结论在窒息致心脏停搏大鼠模型中,氨茶碱对心电活动和自主循环的恢复与肾上腺素疗效相近;氨茶碱和肾上腺素的复苏疗效与剂量相关;较高剂量肾上腺素容易致“石头心”的发生。     

Epidemiology and outcomes of poisoning-induced out-of-hospital cardiac arrest

Objectives

We aimed to describe and compare the epidemiologic features and outcomes among patients with poisoning-induced out-of-hospital cardiac arrests (POHCAs) according to causative agent groups.

Methods

We identified emergency medical service (EMS)-treated POHCA patients from a nationwide OHCA registry between 2006 and 2008, which was derived from EMS run sheets and followed by hospital record review. Utstein elements were collected and hospital outcomes (survival to admission and to discharge) were measured. We compared risk factors and outcomes according to the main poisons. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from a multivariate logistic regression model for hospital outcomes.

Results

The total number of non-cardiac aetiology OHCAs was 20,536. Of these, the number of EMS-assessed and EMS-treated POHCAs was 900 (4.4%). For EMS-treated POHCAs, insecticides (n = 111, 15.5%) including organophosphate and carbamates; herbicides (n = 94, 13.2%); unknown pesticides (n = 142, 19.9%); non-pesticide drugs (n = 120, 16.8%); and unknown poisons (n = 247, 6%) were identified. The survival to admission rate was 22.5% for insecticides, 3.2% for herbicides, 16.2% for unknown pesticides, 16.7% for non-pesticides and 11.3% for the unknown group. The survival to discharge rates were 9.9% for insecticides, 0.0% for herbicides, 2.1% for unknown pesticides, 3.3% for non-pesticides and 3.2% for the unknown group. The adjusted OR for each group for survival to admission was significantly lower when compared with insecticides: herbicides (OR = 0.11, 95% CI = 0.03-0.44), non-pesticide drugs (OR = 0.28, 95% CI = 0.13-0.61) and unknown group (OR = 0.40, 95% CI = 0.21-0.76). The adjusted OR for each group for survival to discharge was significantly lower when compared with insecticides: herbicides (OR < 0.01, 95% CI < 0.01 or >99.9), unknown pesticides (OR = 0.23, 95% CI = 0.0.06-0.87), non-pesticide drugs (OR = 0.14, 95% CI = 0.04-0.54) and unknown group (OR = 0.30, 95% CI = 0.11-0.83).

Conclusion

Using a nationwide OHCA registry, we found that poisonings were responsible for 4.4% of OHCAs of a non-cardiac aetiology. Ingestion of insecticides including organophosphate and carbamate was associated with more favourable outcomes.     

Association between hospital post-resuscitative performance and clinical outcomes after out-of-hospital cardiac arrest

BackgroundSurvival varies among those resuscitated from out-of-hospital cardiac arrest (OHCA). Evidence-based performance measures have been used to describe hospital quality of care in conditions such as acute coronary syndrome and major trauma. It remains unclear if adherence to performance measures is associated with better outcome in patients hospitalized after OHCA.ObjectivesTo assess whether a composite performance score based on evidence-based guidelines for care of patients resuscitated from OHCA was independently associated with clinical outcomes.MethodsIncluded were 3252 patients with OHCA who received care at 111 U.S. and Canadian hospitals participating in the Resuscitation Outcomes Consortium (ROC-PRIMED) study between June 2007 and October 2009. We calculated composite performance scores for all patients, aggregated these at the hospital level, then associated them with patient mortality and favorable neurological status at discharge.ResultsComposite performance scores varied widely (median [IQR] scores from lowest to highest hospital quartiles, 21% [20%, 25%] vs. 59% [55%, 64%]. Adjusted survival to discharge increased with each quartile of performance score (from lowest to highest: 16.2%, 20.8%, 28.5%, 34.8%, P < 0.01), with similar findings for adjusted rates of good neurologic status. Hospital score was significantly associated with outcome after risk adjustment for established baseline factors (highest vs. lowest adherence quartile: adjusted OR of survival 1.64; 95% CI 1.13, 2.38).ConclusionsGreater survival and favorable neurologic status at discharge were associated with greater adherence to recommended hospital based post-resuscitative care guidelines. Consideration should be given to measuring, reporting and improving hospital adherence to guideline-based performance measures, which could improve outcomes following OHCA.     

Electrical therapies in cardiac arrest

Recognition and appropriate treatment of ventricular fibrillation or pulseless ventricular tachycardia is an essential skill for healthcare providers. Appropriate defibrillation can improve survival and benefit patient outcome. Similarly, increased public access to automatic electronic defibrillators has been shown to improve out-of-hospital survival for cardiac arrest. When combined with high-quality cardiopulmonary resuscitation, electrical therapies are an important aspect of resuscitation in the patient with cardiac arrest. This article focuses on the use of electrical therapies, including defibrillation, cardiac pacing, and automated external defibrillators, in cardiac arrest.     

The relationship between age and outcome in out-of-hospital cardiac arrest patients

AimTo determine the association between age and outcome in a large multicenter cohort of out-of-hospital cardiac arrest patients.MethodsRetrospective, observational, cohort study of out-of-hospital cardiac arrest from the CARES registry between 2006 and 2013. Age was categorized into 5-year intervals and the association between age group and outcomes (return of spontaneous circulation (ROSC), survival and good neurological outcome) was assessed in univariable and multivariable analysis. We performed a subgroup analysis in patients who had return of spontaneous circulation.ResultsA total of 101,968 people were included. The median age was 66 years (quartiles: 54, 78) and 39% were female. 31,236 (30.6%) of the included patients had sustained ROSC, 9761 (9.6%) survived to hospital discharge and 8058 (7.9%) survived with a good neurological outcome. The proportion of patients with ROSC was highest in those with age <20 years (34.1%) and lowest in those with age 95–99 years (23.5%). Patients with age <20 years had the highest proportion of survival (16.7%) and good neurological outcome (14.8%) whereas those with age 95–99 years had the lowest proportion of survival (1.7%) and good neurological outcome (1.2%). In the full cohort and in the patients with ROSC there appeared to be a progressive decline in survival and good neurological outcome after the age of approximately 45–64 years. Age alone was not a good predictor of outcome.ConclusionsAdvanced age is associated with outcomes in out-of-hospital cardiac arrest. We did not identify a specific age threshold beyond which the chance of a meaningful recovery was excluded.     

Incidence and outcome from adult cardiac arrest occurring in the intensive care unit: A systematic review of the literature

Background

Significant amount of data on the incidence and outcome of out-of-hospital and in-hospital cardiac arrest have been published. Cardiac arrest occurring in the intensive care unit has received less attention.

Aims

To evaluate and summarize current knowledge of intensive care unit cardiac arrest including quality of data, and results focusing on incidence and patient outcome.

Sources and methods

We conducted a literature search of the PubMed, CINAHL and Cochrane databases with the following search terms (medical subheadings): heart arrest AND intensive care unit OR critical care OR critical care nursing OR monitored bed OR monitored ward OR monitored patient. We included articles published from the 1st of January 1990 till 31st of December 2012. After exclusion of all duplicates and irrelevant articles we evaluated quality of studies using a predefined quality assessment score and summarized outcome data.

Results

The initial search yielded 794 articles of which 780 were excluded. Three papers were added after a manual search of the eligible studies’ references. One paper was identified manually from the literature published after our initial search was completed, thus the final sample consisted of 18 papers. Of the studies included thirteen were retrospective, two based on prospective registries and three were focused prospective studies. All except two studies were from a single institution. Six studies reported the incidence of intensive care unit cardiac arrest, which varied from 5.6 to 78.1 cardiac arrests per 1000 intensive care unit admissions. The most frequently reported initial cardiac arrest rhythms were non-shockable. Patient outcome was variable with survival to hospital discharge being in the range of 0–79% and long-term survival ranging from 1 to 69%. Nine studies reported neurological status of survivors, which was mostly favorable, either no neurological sequelae or cerebral performance score mostly of 1–2. Studies focusing on post cardiac surgery patients reported the best long-term survival rates of 45–69%.

Conclusions

At present data on intensive care unit cardiac arrest is quite limited and originates mostly from retrospective single center studies. The quality of data overall seems to be poor and thus focused prospective multi-center studies are needed.     

Survival after avalanche-induced cardiac arrest

Aim

Criteria to prolong resuscitation after cardiac arrest (CA) induced by complete avalanche burial are critical since profound hypothermia could be involved. We sought parameters associated with survival in a cohort of victims of complete avalanche burial.

Methods

Retrospective observational study of patients suffering CA on-scene after avalanche burial in the Northern French Alps between 1994 and 2013. Criteria associated with survival at discharge from the intensive care unit (ICU) were collected on scene and upon admission to Level-1 trauma center. Neurological outcome was assessed at 3 months using cerebral performance category score.

Results

Forty-eight patients were studied. They were buried for a median time of 43 min (25–76 min; 25–75th percentiles) and had a pre-hospital body core temperature of 28.0 °C (26.0–30.7). Eighteen patients (37.5%) had pre-hospital return of spontaneous circulation and 30 had refractory CA. Rewarming of 21 patients (43.7%) was performed using extracorporeal life support. Eight patients (16.7%) survived and were discharged from the ICU, three (6.3%) had favorable neurological outcome at 3 months. Pre-hospital parameters associated with survival were the presence of an air pocket and rescue collapse. On admission, survivors had lower serum potassium concentrations than non-survivors: 3.2 mmol/L (2.7–4.0) versus 5.6 mmol/L (4.2–8.0), respectively (P < 0.01). They also had normal values for prothrombin and activated partial thromboplastin compared to non-survivors.

Conclusions

Our findings indicate that survival after avalanche burial and on-scene CA is rarely associated with favorable neurological outcome. Among criteria associated with survival, normal blood coagulation on admission warrants further investigation.     

窒息性心跳骤停家猪心脏节律变化

目的 观察成年家猪在诱导窒息性心跳骤停过程中心脏节律变化特点.方法 对16头成年家猪在呼气末夹闭气管,直至动脉搏动压消失,造成窒息性心跳骤停模型后,再延长窒息8 min,随即开始常规心肺复苏(cardiopulmonary resuscitation,CPR).CPR 3 min后给予肾上腺素0.045 mg/kg静脉注射.复苏20 min内恢复自主循环(restoration of spontaneous circulation,ROSC)的家猪定义为CPR成功,反之界定为死亡.记录各动物从窒息前到CPR开始即刻的心电图.结果 达到心跳骤停标准的即刻,16头家猪中2头心电图表现为心室颤动(ventricular fibrillation,VF),4头表现为全心停搏(asys-tole),其余10头呈现无脉性电活动(pulseless electrical activity,PEA).在施行CPR前的8 min非干预时间内,原呈现PEA的10头猪中7头转变成VF.施行CPR的即刻,9头猪表现为VF,3头表现为PEA,4头表现为全心停搏.结论 绝大多数成年家猪在诱导窒息性心跳骤停过程中发生PEA,但在延长窒息时间后PEA绝大多数转变为vF.     

Major differences in 1-month survival between hospitals in Sweden among initial survivors of out-of-hospital cardiac arrest

AIM: To explore the rate of survival to hospital discharge among patients who were brought to hospital alive after an out-of-hospital cardiac arrest in different hospitals in Sweden. PATIENTS AND METHODS: All patients who had suffered an out-of-hospital cardiac arrest which was not witnessed by the ambulance crew, in whom cardiopulmonary resuscitation (CPR) was started and who had a palpable pulse on admission to hospital were evaluated for inclusion. Each participating ambulance organisation and its corresponding hospital(s) required at least 50 patients fulfilling these criteria. RESULTS: Three thousand eight hundred and fifty three patients who were brought to hospital by 21 different ambulance organisations fulfilled the inclusion criteria. The number of patients rescued by each ambulance organisation varied between 55 and 900. The survival rate, defined as alive 1 month after cardiac arrest, varied from 14% to 42%. When correcting for dissimilarities in characteristics and factors of the resuscitation, the adjusted odds ratio for survival to 1 month among patients brought to hospital alive in the three ambulance organisations with the highest survival versus the three with the lowest survival was 2.63 (95% CI: 1.77-3.88). CONCLUSION: There is a marked variability between hospitals in the rate of 1-month survival among patients who were alive on hospital admission after an out-of-hospital cardiac arrest. One possible contributory factor is the standard of post-resuscitation care.     

Prognosis in cardiac arrest

Cardiac arrest remains a common problem throughout the world. This article explores several factors that aid in determining prognosis after cardiac arrest. It is broadly divided into prearrest factors, intra-arrest factors, and postarrest factors. Prearrest factors predominantly concern the presence or absence of a shockable rhythm. Intra-arrest factors look at the partial pressure of end-tidal CO2 and the presence of cardiac standstill on ultrasound. Postarrest factors include early outcome measures as well as a more comprehensive algorithmic approach to predicting neurologic outcome.