Sudden cardiac death: directing the scope of resuscitation towards the heart and brain

BACKGROUND: The fundamental goal of cardiopulmonary resuscitation (CPR) is recovery of the heart and the brain. This is best achieved by (1) immediate CPR for coronary and cerebral perfusion, (2) correction of the cause of cardiac arrest, and (3) controlled cardioplegic cardiac reperfusion. Failure of such an integrated therapy may cause permanent brain damage despite cardiac resuscitation. METHODS: This strategy was applied at four centers to 34 sudden cardiac death patients (a) after acute myocardial infarction (n = 20), (b) "intraoperatively" following successful discontinuation of cardiopulmonary bypass (n = 4), and (c) "postoperatively" in the surgical ICU (n = 10). In each witnessed arrest the patient failed to respond to conventional CPR with ACLS interventions, including defibrillation. The cardiac arrest interval was 72 +/- 43 min (20-150 min). Compression and drugs maintained a BP > 60 mmHg to avoid cerebral hypoperfusion. Operating room (OR) transfer was delayed until the blood pressure was monitored. In four patients femoral bypass maintained perfusion while an angiographic diagnosis was made. RESULTS: Management principles included no repeat defibrillation attempts after 10 min of unsuccessful CPR, catheter-monitored peak BP > 60 mmHg during diagnosis and transit to the operating room, left ventricular venting during cardiopulmonary bypass and 20 min global and graft substrate enriched blood cardioplegic reperfusion. Survival was 79.4% with two neurological complications (5.8%). CONCLUSIONS: Recovery without adverse neurological outcomes is possible in a large number of cardiac arrest victims following prolonged manual CPR. Therapy is directed toward maintaining a monitored peak BP above 60 mmHg, determining the nature of the cardiac cause, and correcting it with controlled reperfusion to preserve function.     

Outcome of avalanche victims with out-of-hospital cardiac arrest

Study backgroundPrevious studies focused on the outcome of avalanche victims with out-of-hospital cardiac arrest (OHCA) after long duration of burial (>35 min); the outcome of victims with short duration (≤35 min) remains obscure.Aim of the studyTo investigate outcome of avalanche victims with OHCA.MethodsRetrospective analysis of avalanche victims with OHCA between 2008 and 2013 in the Tyrolean Alps.Results55 avalanche victims were identified, 32 of whom were declared dead after extrication without cardiopulmonary resuscitation (CPR), all with long duration of burial. In the remaining 23 CPR was initiated at scene; three were partially and 20 completely buried, nine of whom suffered short and 11 long duration of burial. All nine victims with short duration of burial underwent restoration of spontaneous circulation (ROSC) at scene, four of them after bystander CPR, five after advanced life support by the emergency physician. Two patients with ROSC after short duration of burial and bystander CPR survived to hospital discharge with cerebral performance category 1. None of the 11 victims with long duration of burial survived to hospital discharge, although six were transported to hospital with ongoing CPR and three were supported with extracorporeal circulation.ConclusionsIn this case series survival with favourable neurological outcome was observed in avalanche victims with short duration of burial only if bystander CPR was immediately performed and ROSC achieved. Strategies for reducing avalanche mortality should focus on prompt extrication from the snow and immediate bystander CPR by uninjured companions.     

What Is the Quality of Life for Survivors of Cardiac Arrest? A Prospective Study

Objective: To evaluate the quality of life of survivors of in-hospital and out-of-hospital cardiac arrest, and to correlate quality of life with clinically important parameters. Methods: Cohort followed at least six months after hospital discharge. Eligible patients had survived to hospital discharge after sudden cardiac arrest in 1) EDs, wards, and intensive care units of five university hospitals and 2) all locations outside hospitals in two midsized cities. Of 126 patients discharged alive, 30 died before they could be interviewed. Of the 96 patients remaining, 86 (90% of available patients, 68% of survivors to discharge) completed the interview. Quality of life was assessed with the Health Utilities Index Mark 3, which describes health as a utility score on a scale from perfect health (equal to 1.0) to death (equal to 0.) Results: Mean age (±SD) of interviewed survivors was 65 ± 14 years, and 47 (55%) were male; mean time between collapse and initiation of CPR was 2.2 ± 2.6 minutes. Mean utility was 0.72 (±0.22). Utilities were significantly higher among patients who had a shorter duration of resuscitation (mean ? 0.81 for those who received less than 2 minutes of CPR, 0.76 for those who received 3 to 10 minutes, and 0.65 for others, p ? 0.05, r²? 0.07). Mean utilities of survivors were worse than those of the general population (mean ? 0.85 ± 0.16, p < 0.01) and those whose activities were not limited by chronic disease (mean ? 0.91 ± 0.08, p < 0.01). Conclusions: Although overall survival was poor, most survivors had acceptable health-related quality of life. Therefore, concerns about poor quality of life are not a valid reason to abandon efforts to improve the health care system's response to victims of sudden cardiac arrest. Further research is necessary to identify effective strategies for improving both survival and quality of life after cardiac arrest.     

Effects of naloxone on the adrenomedullary response during and after cardiopulmonary resuscitation in dogs

To determine the effects of naloxone, an opiate antagonist, on the adrenomedullary response to cardiac arrest, plasma epinephrine and norepinephrine levels were measured before, during, and after cardiac arrest in dogs. Ventricular fibrillation was induced in 12 dogs anesthetized with pentobarital sodium (30 mg/kg) and standard American Heart Association cardiopulmonary resuscitation (CPR) was begun using a mechanical device. At 6.5 minutes of CPR, naloxone (10 mg/kg) or 0.9% saline (10 ml) was given intravenously. At 12 minutes of CPR, the cardiac ventricles were electrically defibrillated. Plasma epinephrine and norepinephrine levels were measured before ventricular fibrillation; at 2.5, 4.5, 9.5, and 11.5, minutes of CPR; and at 5, 10, 15, and 20 minutes after resuscitation. Epinephrine and norepinephrine increased from prearrest levels of 3.66 +/- 0.67 (+/- SE) and 24.02 +/- 3.67 ng/ml to 66.67 +/- 9.65 and 74.00 +/- 9.91 ng/ml, respectively, at 4.5 minutes of CPR. After resuscitation, norepinephrine levels remained slightly elevated, while epinephrine fell to prearrest levels. Naloxone did not cause a significant change in either epinephrine or norepinephrine from 6.5 minutes of CPR (time of treatment) through 20 minutes postresuscitation. In addition, naloxone had no effect on either the end-diastolic pressure difference during CPR or resuscitation outcome. We conclude that cardiac arrest causes significant increases in plasma epinephrine and norepinephrine levels, which remain elevated for the duration of the arrest, and that naloxone has no effect on these levels.     

Rapid change in pulmonary vascular hemodynamics with pulmonary edema during cardiopulmonary resuscitation

Previous studies have shown that pulmonary edema occurs in half of all pre-hospital cardiac arrest victims who cannot be successfully resuscitated and is a major cause of hypoxemia and poor lung compliance during resuscitation. Pulmonary vascular hypertension and elevation of pulmonary capillary wedge pressure have been observed during cardiac resuscitation in humans. To further define the time course of the pulmonary hemodynamic changes, pulmonary artery diastolic pressure (PAd) was measured on a computerized trend recorder prior to, during, and immediately after arrest in three adult patients. Prior to arrest, PADP was 20.9 +/- 3.1 mm Hg. The PADP rose in all three patients by an average of 30.6% after 5-10 minutes and 71.3% after 10-15 minutes of CPR. Peak PADP reached 35.8 +/- 5.1 mm Hg (difference from pre-arrest level significant, P less than 0.001). In both patients who were resuscitated successfully, the PADP returned to baseline within 5 minutes of effective spontaneous circulation. The finding that such hemodynamic changes occur rapidly during resuscitation and can reverse quickly with resumption of effective spontaneous circulation is consistent with the time course for the early development of pulmonary edema. Development of pulmonary edema many hours following successful resuscitation likely involves other mechanisms.     

心脏骤停复苏后肾脏功能变化的研究

目的:探讨心脏骤停心肺复苏后肾脏功能的变化规律。方法:将30只兔随机分为假手术组、心脏骤停即刻复苏组和心脏骤停5min组,每组10只。假手术组仅进行麻醉和逆行气管插管、血管穿刺,不进行气管夹闭窒息,心脏骤停组用气管夹闭窒息法致使心跳骤停,分别于心跳骤停后0、5min进行复苏,分别在0、24、48、72h和96h5个时间点取血样,测定血肌酐、胱抑素C的变化,对动物肾脏功能进行评估。结果:即刻复苏组与假手术组比较,各时间点血肌酐轻度升高,但差异无统计学意义;复苏后24h血胱抑素C表达明显增高,然后逐渐降低,复苏后120h血胱抑素C再次升高;各时间点胱抑素C与假手术组比较差异有统计学意义。心跳骤停5min组复苏后各时间点血肌酐、胱抑素C表达明显升高,与假手术组比较差异有统计学意义(P0.01)。心跳骤停5min组血肌酐以复苏后48h最高,然后逐渐降低,而胱抑素C在复苏后24h即显著升高,持续至复苏后120h仍然处于较高水平。结论:心脏骤停心肺复苏后,肾功能损害出现早,持续时间长,在复苏后120h可能再次出现肾功能损害。     

Arterial base excess after CPR: the relationship to CPR duration and the characteristics related to outcome

OBJECTIVE: We aimed (1) to determine the relationship between arterial base excess (BE) immediately after the restoration of spontaneous circulation (ROSC) and duration of cardiopulmonary resuscitation (CPR) and (2) to ascertain the value of admission BE data as a predictor of mortality in patients resuscitated from cardiac arrest (CA). DESIGN: Retrospective chart review. SETTING: An emergency department of a teaching hospital. PATIENTS: Eighty-seven patients who presented with non-traumatic out-of-hospital witnessed CA between January 2001 and December 2004 in whom arterial blood gas (ABG) analysis was performed within 10 min after ROSC. MEASUREMENTS AND MAIN RESULTS: Individual medical records were reviewed for demographic characteristics; cause of CA; electrocardiogram pattern at the scene; CPR duration; ABG data; outcome (survival to discharge or in-hospital death). Significant correlations were observed between CPR duration and BE in all 87 patients (r = 0.51, p < 0.01) and in the 66 non-survivors (r = 0.46, p < 0.01), but not in the 21 survivors. Mean arterial BE in survivors was significantly higher than that observed in non-survivors (-15.3 +/- 5.7 mmol/L versus -19.1 +/- 6.3 mmol/L). Mean CPR duration was 34 +/- 16 min in non-survivors and 18 +/- 10 min in survivors (p<0.01). Multivariate logistic analysis showed that significant predictors of survival included cardiac aetiology (odds ratio, 6.3; 95% confidence interval, 1.2-33; p<0.01), ventricular fibrillation at the scene (odds ratio, 7.4; 95% confidence interval, 1.4-39.9; p<0.01), and CPR duration 相似文献   

Two-year survival and neurodevelopmental outcomes after cardiopulmonary resuscitation in neonatal patients after complex cardiac surgery

Aim

To examine survival and neurodevelopmental outcomes in neonates having post-operative cardiopulmonary resuscitation (CPR).

Methods

This inception cohort study included all neonates (6 weeks old or less) who received postoperative CPR (Group 1) after cardiac surgery from 1996 to 2005, matched for heart defect, year of surgery, chromosomal abnormality, and socioeconomic status to two neonates who did not receive postoperative CPR (Group 2). Two-year neurodevelopment was prospectively assessed with Bayley Scales of Infant Development II and Adaptive Behavior Assessment System II. Pre-, intra-, and post-operative variables were collected prospectively. Cardiac arrest variables were collected retrospectively. Predictors of mortality were analyzed by univariate analysis and conditional multiple logistic regression.

Results

There were 29 patients in Group 1, and 58 patients in Group 2. In survivors, there were no significant differences between Groups 1 and 2 in outcomes [mean (SD)] of mental developmental index [84.5 (12.2) vs. 81.0 (18.9)], psychomotor developmental index [82.8 (13.8) vs. 80.1 (21.9)], General Adaptive Composite [84.6 (15.3) vs. 84.3 (19.2)], Motor scale [8.4 (3.2) vs. 8.0 (3.8)], or delay on any of these scales. Two-year mortality [58.6% Group 1; 8.6% Group 2], was associated on conditional multiple logistic regression with CPR (OR 26.6; 95% CI, 5.4, 129.5). In Group 1, on multiple logistic regression, 2-year mortality was associated with minutes of chest compressions (OR 1.04, 95% CI, 1.01, 1.08).

Conclusions

Among neonates having cardiac surgery, CPR is associated with greater mortality. There is no evidence that CPR survivors have different 2-year neurodevelopmental outcomes than those neonates not having CPR.     

H ANDBOOK OF U RGENT C ARE M EDICINE , 2 ND E DITION

Abstract

Background. Hyperglycemia is common in the early period following resuscitation from cardiac arrest and has been shown to be a predictor of neurologic outcome in retrospective studies. Objective. To evaluate neurologic outcome and early postarrest hyperglycemia in a swine cardiac arrest model. Methods. Electrically induced ventricular fibrillation cardiac arrest was induced in 22 anesthetized and instrumented swine. After 7 minutes, cardiopulmonary resuscitation (CPR) and Advanced Cardiac Life Support were initiated. Twenty-one animals were resuscitated and plasma glucose concentration was measured at intervals for 60 minutes after resuscitation. The animals were observed for 72 hours and the neurologic score was determined at 24-hour intervals. Results. Ten animals had a peak plasma glucose value ≥226 mg/dL during the initial 60 minutes after resuscitation. The neurologic scores at 72 hours in these animals (mean score = 0, mean overall cerebral performance category = 1) were the same as those in the animals with a peak plasma glucose value <226 mg/dL. The end-tidal carbon dioxide (CO₂) values measured during CPR, times to restoration of spontaneous circulation, and epinephrine doses were not significantly different between the animals with a peak glucose concentration ≥226 mg/dL and those with lower values. The sample size afforded a power of 95% to detect a 50-point difference from the lowest score (0 points) of the porcine neurologic outcome scale. Conclusion. In this standard porcine model of witnessed out-of-hospital cardiac arrest, early postresuscitation stress hyperglycemia did not appear to affect neurologic outcome. During the prehospital phase of treatment and transport, treatment of hyperglycemia by emergency medical services providers may not be warranted.     

体外心肺复苏技术在成人心搏骤停抢救中的应用

目的 回顾性总结应用体外心肺复苏(E-CPR)技术救治成人心搏骤停患者的临床经验.方法 2005年7月至2009年7月,有11例心源性心搏骤停成人患者(男7例,女4例,年龄24～71岁)经常规心肺复苏(CPR)抢救10～15 min无法有效恢复自主循环,而采用E-CPR技术抢救.7例心脏手术后患者在CPR抢救同时自原胸骨切口先建立升主动脉-右心房常规体外循环辅助,再转为体外膜肺氧合(ECMO)辅助;4例患者在CPR抢救同时直接经股动、静脉置管建立ECMO辅助.结果 11例患者CPR时间30～90 min,平均(51±14)min,10例患者可恢复自主心律.11例患者ECMO辅助时间2～223 h,中位时间126 h.6例患者成功撤离ECMO辅助,但存活出院率为36.4%(4/11).2例患者在ECMO辅助的同时加用主动脉内球囊反搏术(IABP),1例存活.3例患者因合并肾功能衰竭而需血液滤过治疗.结论 E-CPR为抢救危重的心搏骤停患者提供了一个新的手段.如何有效评估和选择病例,及时开始救治以提高成功率,值得进一步研究.     

Resuscitation: when is enough, enough?

Almost half of patients respond acutely to resuscitation but most die within the first several days after arrest. The incidence of survival to discharge from the hospital after cardiopulmonary arrest is about 15%; one third of those surviving have evidence of neurologic deficits. Although some prognostic variables are useful in determining which patients are most likely to die prior to discharge from the hospital, each patient needs to be evaluated on an individual basis and the various risk factors weighed carefully. As additional data accumulate, we may well be more effective at deciding which patients are more likely to benefit from CPR so that we can more judiciously apply this therapeutic modality. A number of studies have identified factors that contribute to poor outcome. Patients over 70 years of age usually fare poorly after CPR, but this is more a reflection of the number of coexisting diagnoses rather than years. Although initial survival may not be different from younger patients, fewer elderly patients live to discharge and more are likely to have neurologic sequelae. Concurrent diagnoses such as sepsis, AIDS, gastrointestinal bleeding, renal failure, cancer, and central nervous system disease have a universally poor response to CPR. If defibrillation occurs more than 6 minutes after arrest or on the general ward or if the resuscitative attempt lasts longer than 15 minutes, mortality is greater than 95%. If CPR continues for more than 30 minutes, there are no survivors. A low exhaled CO2 concentration (< 2%) during cardiac massage, asystole or EMD as the first identified rhythm, and recurrent arrest also carry a poor prognosis. On the other hand, at the time of arrest or during the immediate postarrest period, poor neurologic status is a less helpful predictor. The absence of spontaneous respiration is the only variable at the time of admission after out-of-hospital arrest that is particularly ominous. There is no evidence to suggest that the absence of spontaneous respiration implies any better prognosis for patients arresting in the hospital. Coma, hypoxic myoclonus, and absent reflexes, while not useful immediately following arrest, are of greater prognostic significance 48 hours later. Only 5% of patients who are unconscious 48 hours after arrest will have a full neurologic recovery. The Glasgow Coma Scale has also been used for prognostication.(ABSTRACT TRUNCATED AT 400 WORDS)     

Excellent coronary perfusion pressure during cardiopulmonary resuscitation is not good enough to ensure long-term survival with good neurologic outcome: a porcine case report

PURPOSE: To report a case of cerebral ischemia confirmed by magnetic resonance imaging after successful cardiopulmonary resuscitation (CPR) complicated by acute respiratory injury. MATERIALS AND METHODS: After 4 min of cardiac arrest, followed by 3 min of basic life support CPR, a female pig weighing 38 kg received every 5 min vasopressin (0.4, 0.4 and 0.8 U/kg). After 22 min of cardiac arrest, including 18 min of CPR, one defibrillation attempt employing 100 J resulted in return of spontaneous circulation. Neurological evaluation was performed 24 and 96 h after successful CPR. Magnetic resonance imaging was carried out 4 days after CPR using a clinical 1.5 T scanner. The magnetic resonance imaging protocol consisted of fast spinecho T2-weighted, as well as spinecho T1-weighted imaging of the brain. RESULTS: CPR with vasopressin resulted in excellent coronary perfusion pressure ranging between 35 and 60 mm Hg throughout CPR. Eight minutes after initiation of chest compressions, bleeding out of the tracheal tube occurred. This was later confirmed as originating from bilateral bloody pulmonary infiltrations, resulting in acute respiratory injury in the post-resuscitation phase. Ninety-six hours after successful CPR, magnetic resonance imaging revealed bilateral diffuse cerebral vasogenic edema. CONCLUSION: Although excellent coronary perfusion pressure renders a return of spontaneous circulation more likely, complications such as acute respiratory injury in the post-resuscitation phase have to be managed carefully in order to ensure good neurological recovery from cardiac arrest.     

One-year survival and neurological outcome after pediatric cardiopulmonary resuscitation

OBJECTIVE: Reported survival after cardiopulmonary resuscitation (CPR) in children varies considerably. We aimed to identify predictors of 1-year survival and to assess long-term neurological status after in- or outpatient CPR. DESIGN: Retrospective review of the medical records and prospective follow-up of CPR survivors. SETTING: Tertiary care pediatric university hospital. PATIENTS AND METHODS: During a 30-month period, 89 in- and outpatients received advanced CPR. Survivors of CPR were prospectively followed-up for 1 year. Neurological outcome was assessed by the Pediatric Cerebral Performance Category scale (PCPC). Variables predicting 1-year survival were identified by multivariable logistic regression analysis. INTERVENTIONS: None. RESULTS: Seventy-one of the 89 patients were successfully resuscitated. During subsequent hospitalization do-not-resuscitate orders were issued in 25 patients. At 1 year, 48 (54%) were alive, including two of the 25 patients with out-of-hospital CPR. All patients died, who required CPR after trauma or near drowning, when CPR began >10 min after arrest or with CPR duration >60 min. Prolonged CPR (21-60 min) was compatible with survival (five of 19). At 1 year, 77% of the survivors had the same PCPC score as prior to CPR. Predictors of survival were location of resuscitation, CPR during peri- or postoperative care, and duration of resuscitation. A clinical score (0-15 points) based on these three items yielded an area under the ROC of 0.93. CONCLUSIONS: Independent determinants of long-term survival of pediatric resuscitation are location of arrest, underlying cause, and duration of CPR. Long-term survivors have little or no change in neurological status.     

Therapeutic hypothermia for a comatose survivor of near-hanging

Therapeutic hypothermia is recommended for comatose survivors of cardiac arrest. Therapeutic hypothermia ameliorates multiple pathophysiologic mechanisms involved in ischemia-reperfusion injury, which may occur after cardiac arrest and near-hanging. Therapeutic hypothermia has not been prospectively studied in near-hanging. Victims of near-hanging suffer from strangulation with cerebral ischemia and resultant reperfusion injury rather than a fatal cervical spine injury. We report a case where therapeutic hypothermia was applied to a comatose survivor of near-hanging. A 41-year-old man presented with coma following attempted suicide by hanging. The patient underwent 24 hours of mild therapeutic hypothermia. The patient was discharged without neurologic sequelae and a Modified Rankin Scale of 0 (back to his baseline status). We present a case where therapeutic hypothermia was used safely and successfully in a patient without cardiac arrest but still in coma after attempted suicide by hanging. No randomized controlled trials on therapeutic hypothermia for comatose survivors of near-hanging victims have been published. However, in the absence of better evidence, it seems reasonable to consider hypothermia treatment in comatose near-hanging victims until more evidence can be obtained.     

心肺复苏后犬脑组织一氧化氮浓度的变化及纳络酮的干预

目的:探讨犬心肺复苏(CPR)后6h脑组织形态学和一氧化氮(NO)浓度的变化以及纳络酮对两者的影响。方法:18只健康杂种犬随机分成三组(n=6),空白组:不诱发室颤,6h后取脑组织;对照组:心跳骤停后予常规心肺复苏术;纳络酮组:心跳骤停后予常规心肺复苏术并使用纳络酮。对照组和纳络酮组于复苏后6h取脑组织行NO浓度测定以及形态学检查。结果:对照组脑组织NO的含量高于空白组和纳络酮组,均P<0.01。纳络酮组的病理损害低于对照组。结论:纳络酮可减轻心肺复苏后脑组织NO的生成,减轻神经元的再灌注损伤。     

亚低温治疗对心搏骤停心肺复苏患者预后影响

目的 探讨亚低温治疗对心搏骤停后心肺复苏患者的临床疗效,寻找一种切实可行的亚低温治疗的监测指标.方法 选取2005年1月至2010年2月中国医科大学附属盛京医院急诊科收治的心搏骤停患者40例,经心肺复苏(PCR)达到自主循环恢复后随机分为常规治疗组与亚低温治疗组各20例.随访3个月观察其临床疗效,同时监测局部脑组织的氧饱和度(rSO2)在亚低温治疗各时点的变化.结果 亚低温治疗组治愈率显著高于常规治疗组;亚低温治疗组的致残率显著低于常规治疗组.亚低温治疗12 h后rS02明显上升,24 h后rSO2持续维持在稳定状态,与对照组相比差异具有统计学意义(P＜0.01).结论 对心搏骤停后心肺复苏患者实行亚低温治疗能减轻脑组织氧代谢紊乱,改善预后.无创持续监测rSO2对亚低温治疗具有指导意义.     

心肺复苏的质量对复苏后炎症反应的影响

目的 评价临床上常见的不标准心肺复苏(N-CPR)和2005年国际CPR指南推荐的标准心肺复苏(S-CPR)对心脏停搏(CA)猪复苏后炎症反应的影响.方法 18头猪被随机均分成两组,经麻醉、插管、机械通气后,应用程控刺激方法制备心室纤颤(VF)模型.S-CPR组应用2005年指南推荐的CPR方式;N-CPR组模拟临床上经常出现的低质量CPR方式.VF 4 min后开始进行CPR,CPR 9 min后进行电除颤及高级生命支持,自主循环恢复(ROSC)后进行各项指标观察.24 h仍存活的猪经处死后取脑、心、肝、肾组织,应用免疫组化法检测核转录因子-kB(NF-kB)的表达.实验期间连续监测CPR后3、6和9 min的血流动力学变化,并抽取基础状态、CPR 9 rain、ROSC 4 h的静脉血,测定血清肿瘤坏死因子-a(TNF-α)、白细胞介素-1β(IL-1β)的浓度.结果 与N-CPR组比较,S-CPR组ROSC率(22.2%比88.9%)及24 h存活率(22.2%比88.9%)明显提高(P均＜0.05);CPR后3、6和9 min心排血量(CO)和平均动脉压(MAP)也均显著升高(P均＜0.01);并且CPR后9 min和ROSC 4 h血清促炎症因子TNF-α、IL-1β]水平和各组织NF-kB表达程度均降低.结论 高质量的CPR后不仅能提高CA猪的生存率,也明显改善CPR后的炎症反应.     

Pre-hospital treatment of acute poisonings in Oslo

Background

Cardiac arrest is the leading cause of mortality in Canada, and the overall survival rate for out-of-hospital cardiac arrest rarely exceeds 5%. Bystander cardiopulmonary resuscitation (CPR) has been shown to increase survival for cardiac arrest victims. However, bystander CPR rates remain low in Canada, rarely exceeding 15%, despite various attempts to improve them. Dispatch-assisted CPR instructions have the potential to improve rates of bystander CPR and many Canadian urban communities now offer instructions to callers reporting a victim in cardiac arrest. Dispatch-assisted CPR instructions are recommended by the International Guidelines on Emergency Cardiovascular Care, but their ability to improve cardiac arrest survival remains unclear.

Methods/Design

The overall goal of this study is to better understand the factors leading to successful dispatch-assisted CPR instructions and to ultimately save the lives of more cardiac arrest patients. The study will utilize a before-after, prospective cohort design to specifically: 1) Determine the ability of 9-1-1 dispatchers to correctly diagnose cardiac arrest; 2) Quantify the frequency and impact of perceived agonal breathing on cardiac arrest diagnosis; 3) Measure the frequency with which dispatch-assisted CPR instructions can be successfully completed; and 4) Measure the impact of dispatch-assisted CPR instructions on bystander CPR and survival rates. The study will be conducted in 19 urban communities in Ontario, Canada. All 9-1-1 calls occurring in the study communities reporting out-of-hospital cardiac arrest in victims 16 years of age or older for which resuscitation was attempted will be eligible. Information will be obtained from 9-1-1 call recordings, paramedic patient care reports, base hospital records, fire medical records and hospital medical records. Victim, caller and system characteristics will be measured in the study communities before the introduction of dispatch-assisted CPR instructions (before group), during the introduction (run-in phase), and following the introduction (after group).

Discussion

The study will obtain information essential to the development of clinical trials that will test a variety of educational approaches and delivery methods for telephone cardiopulmonary resuscitation instructions. This will be the first study in the world to clearly quantify the impact of dispatch-assisted CPR instructions on survival to hospital discharge for out-of-hospital cardiac arrest victims.

Trial Registration

ClinicalTrials.gov NCT00664443