Initial Cardiac Arrest Rhythm Research Articles

Primary Cardiac Arrest Following Sport or Exertion in Children Presenting to an Emergency Department

The objective of this study was to describe the characteristics and outcome of pediatric patients presenting to an emergency department (ED) following out-of-hospital primary cardiac arrest (OHPCA), to determine if long-term survival is influenced by specific resuscitation interventions. This was a prospective observational study of cases of OHPCA during sport or exertion in young patients presenting to an ED over a 5-year period. Cases were identified from a resuscitation database, which documented patient demographics, nature of event, emergency treatment, response times, and clinical progress. These data were analyzed to determine outcomes. Nine children were identified who presented following OHPCA during the study period. The mean age was 10.7 (±4.2) years. All were subsequently diagnosed with an underlying primary cardiac disorder. Six patients (66.6%) survived to make a full recovery. All patients who survived had received early chest compressions (within 5 minutes) and early defibrillation (within 10 minutes). The initial cardiac arrest rhythm in all survivors had been an electrically cardiovertable rhythm. Five (83%) of the 6 survivors did not receive epinephrine during resuscitation. The importance of early chest compressions and defibrillation in collapsed young athletes is highlighted in this report. These interventions can result in full long-term neurological recovery. Use of epinephrine in these patients may be dangerous. We suggest that special consideration should be given to this subgroup of patients in the development of future resuscitation guidelines.

Effectiveness of using automated external defibrillator by trained healthcare professionals on survival outcomes among adult patients after in-hospital cardiac arrest: a systematic review.

Review question/objective The objective of this review is to synthesise the best available evidence of the effectiveness of using automated external defibrillator by trained healthcare professionals on survival outcomes in adult patients after in-hospital cardiac arrest. More specifically, the objectives are to identify: the effectiveness of using automated external defibrillator by trained healthcare professionals on return of spontaneous circulation and survival to hospital discharge in adult patients after in-hospital cardiac arrest. Inclusion criteria Types of participants This review will consider studies that include adults 18 years old and above; suffering from cardiac arrest requiring chest compression in in-patient wards, emergency department and out-patient procedures in hospital; presenting with an initial index pulseless (for example, but not limited to, ventricular fibrillation and pulseless ventricular tachycardia, asystole or pulseless electrical activities); presence or absence of co-morbidities such as congestive heart failure, myocardial infarction, diabetes mellitus, renal, hepatic or respiratory insufficiency, motor, cognitive or functional deficits, acute stroke, acute non-stroke neurological disorder, pneumonia, hypotension, sepsis, major trauma, metabolic or electrolyte abnormality, metastatic or haematology malignancy. The exclusion criteria are any age group who suffered out-of-hospital cardiac arrest or adults 18 years old and above suffered in-hospital cardiac arrest with a ‘do not resuscitate’ order (DNR). Types of intervention(s) This review will consider as interventions any use of commercially available automated external defibrillator by trained healthcare professionals for in-hospital cardiac arrest. The comparator of interest is use of manual/standard external defibrillator by trained healthcare professionals for in-hospital cardiac arrest. Types of outcomes This review will consider studies that include the following outcome measures: 1. survival with a return of spontaneous circulation for at least 20 minutes during resuscitation 2. survival to hospital discharge regardless of time to discharge 3. initial cardiac arrest rhythms

Abstract 18031: Effects of Rapid Intravenous Ice-Cold Fluids for Patients Treated with Therapeutic Hypothermia

BACKGROUND Animal data has demonstrated that the sooner cooling is initiated after return of spontaneous circulation (ROSC) from cardiac arrest (CA), the better the outcome. Although rapid infusion of ice-cold intravenous (IV) fluids is feasible, safe, and simple method for induction of hypothermia, it is unclear whether technique of ice-cold IV fluids for induction of hypothermia can increase neurological benefit in patients with ROSC after out-of-hospital CA due to shockable rhythm and non-shockable rhythm. METHODS The J-PULSE-Hypo was conducted a multi-center observational registry to investigate the effects of therapeutic hypothermia. In this study, we investigated the effects of ice-cold IV fluids in patients divided into initial CA rhythm (shockable rhythm and non-shockable rhythm). The primary endpoint was favorable neurological outcome at hospital discharge. RESULTS Of the 452 unconscious adult patients who were treated with therapeutic hypothermia after out-of-hospital CA due to cardiac etiology, 435 who were cooled from 32°C to 34°C using external devices or extracorporeal devices were included; 228 received induction of cooling using rapid infusion of ice-cold IV fluids, including 185 shockable CA and 43 non-shockable CA, and 215 did not receive ice-cold IV fluids, including 156 shockable CA and 59 non-shockable CA. The time interval from ROSC to induction of cooling was shorter in the IV group than in the non-IV group in each CA rhythm (median; 28 minutes vs. 133 minutes in the shockable CA, p<0.0001, 21 minutes vs. 81 min in the non-shockable CA, p<0.0001). The IV group had higher frequency of favorable neurological outcome than the non-IV group in the patients with shockable CA (68.6% vs.57.7%, p=0.036), but the two groups had similar frequency of favorable neurological outcome in the patients with non-shockable CA. Adjusted odds ratios for favorable neurological outcome after the IV group was 1.66 (95% CI, 1.04-2.65) in the patients with shockable CA, and 0.53 (95% CI, 0.20-1.40) in the patients with non-shockable CA. CONCLUSION Rapid infusion of ice-cold IV fluids for induction of hypothermia had neurological benefit for patients with shockable CA, but it had not neurological benefit for patients with non-shockable CA.

Paediatric hanging associated out of hospital cardiac arrest in Melbourne, Australia: characteristics and outcomes

IntroductionHanging is a rare but devastating cause of out of hospital cardiac arrest (OHCA). The characteristics and outcomes of hanging associated OHCA in the paediatric age group are described.MethodsThe Victorian...

Improved survival in the real world with revised cardiopulmonary resuscitation guidelines: Doing better out of hospital but not out of the woods yet

Improved survival in the real world with revised cardiopulmonary resuscitation guidelines: Doing better out of hospital but not out of the woods yet

Implementing the 2005 American Heart Association Guidelines improves outcomes after out-of-hospital cardiac arrest

The purpose of the study was to determine whether applying highly recommended changes in the 2005 American Heart Association (AHA) Guidelines would improve outcomes after out-of-hospital cardiac arrest. In 2005, AHA recommended multiple ways to improve circulation during cardiopulmonary resuscitation (CPR). Conglomerate quality assurance data were analyzed during prospective implementation of the 2005 AHA Guidelines in five emergency medical services (EMS) systems. All EMS personnel were trained in the key new aspects of the 2005 AHA Guidelines, including use of an impedance threshold device. The primary outcome was survival to hospital discharge. Secondary outcomes were return of spontaneous circulation (ROSC), survival by initial cardiac arrest rhythm, and the cerebral performance category (CPC) score at hospital discharge. There were 1,605 patients in the intervention group and 1,641 patients in the control group. Demographics, the rate of bystander CPR, and time from the 911 call for help to arrival of EMS personnel were similar between groups. Survival to hospital discharge was 10.1% in the control group versus 13.1% in the intervention group (P = .007). For patients with a presenting rhythm of ventricular fibrillation/ventricular tachycardia, survival to discharge was 20% in controls versus 32.3% in the intervention group (P <.001). Survival to discharge with a CPC classification of 1 or 2 was 33.3% (10/30) in the control versus 59.6% (31/52) in the intervention group (P = .038). Compared with controls, patients with out-of-hospital cardiac arrest treated with a renewed emphasis on improved circulation during CPR had significantly higher neurologically intact hospital discharge rates.

Rescue shock outcomes during out-of-hospital cardiac arrest

Questions remain about the optimal timing and method for treating ventricular fibrillation (VF) during out-of-hospital cardiac arrest, and a variety of treatment protocols are used. Detailed description of rescue shock outcomes during actual patient care under different protocols would allow rational comparison of treatment strategies. The purpose of this study is to describe rescue shock outcomes in a single system using a specific defibrillation protocol. Patient care records were examined for all adult (age> or =18 years) out-of-hospital cardiac arrest cases treated by an urban paramedic system during a 52-month interval. The immediate outcomes of monophasic rescue shocks were determined from the record and were classified as asystole, VF, restoration of organized electrical activity (ROEA), or restoration of spontaneous circulation (ROSC). Among 1496 cases of cardiac arrest, 654 received a median of 3 (IQR 1,5) rescue shocks. Of these cases, 408 (28%) had an initial rhythm of VF whereas VF developed later during resuscitation in the remainder. For an initial series of three escalating rescue shocks, most cases of ROSC (9%) and ROEA (12%) occurred after the first shock. The likelihood that a rescue shock would result in ROSC or ROEA increased with witnessed collapse, and rescue shock number. An initial rhythm of asystole was associated with a decreased likelihood that a rescue shock would result in ROEA. Witnessed collapse and an initial rhythm other than asystole were associated with an increased likelihood of rescue shock success. There is a small but real incremental gain in ROSC and ROEA from delivering three rescue shocks in rapid succession. The greater incidence of rescue shock success with later rescue shocks suggests that VF responds favorably to ongoing resuscitation.

The Changing Incidence of Ventricular Fibrillation in Milwaukee, Wisconsin (1992–2002)

Objectives. To investigate the changes in annual incidence andsurvival of out-of-hospital cardiac-etiology arrests of different initial rhythms, particularly ventricular fibrillation (VF) andventricular tachycardia (VT), among adults (> 21 years old) in Milwaukee County between 1992 and2002 andestablish correlations with patient andemergency medical services (EMS) system-dependent factors. Methods. The study was a retrospective, observational study of all adult (> 21-year-old) patients with out-of-hospital cardiac-etiology arrests with identifiable rhythm andresuscitation attempted by the Milwaukee County EMS system from 1992 to 2002. Nine thousand one hundred seventy cases were enrolled. Primary outcome measures were changes in annual incidence of initial cardiac arrest rhythm, with a focus on VF/VT. Secondary outcome measures were changes in survival to hospital admission andhospital discharge for VF andVT. Patient andEMS system factors potentially affecting the outcome measures were identified andmodeled using multivariate logistic regression. Results. The incidence of out-of-hospital VF/VT arrests decreased steadily from 37.1 per 100,000 in 1992 to 19.4 per 100,000 in 2002. While the incidences of pulseless electrical activity andoverall cardiac arrest remained unchanged, the incidence of asystole during the study period increased from 27.3/100,000 to 44.9/100,000. Multivariate regression analyses revealed that age < 80 years, male gender, white race, previous cardiac surgery, andcardiac history were patient-dependent factors predictive of VF/VT. Witnessed arrest, public location, andshorter response time were EMS system-dependent factors predictive of VF/VT. Based on observed trends, none of these correlated factors could explain the decrease in the incidence of VF/VT arrests. Rates of patient survival to hospital admission anddischarge were not significantly changed over time. EMS system factors predictive of survival to admission anddischarge were witnessed arrest, public location, anddecreased number of defibrillations. Prior cardiac surgery andabsence of chronic problems were the only patient factors predictive of survival to hospital admission but were not significantly related to survival to hospital discharge. Conclusions. The incidence of out-of-hospital cardiac arrests in adult patients with presenting rhythm of VF/VT declined, while an increase in asystole occurred. This was not explained by any patient or EMS system-dependent factor. Rate of survival for VF/VT arrest did not significantly change over time. Survival was primarily influenced by EMS system factors andunrelated to patient-dependent factors.

Recall after cardiac arrest scenario testing

The Resuscitation Council (UK) Advanced Life Support (ALS) Course is a multidisciplinary training course which teaches participants how to manage the resuscitation of a patient at risk of or in cardiac arrest. To reduce variability in assessments, four standardised patient scenarios have been developed with common performance criteria. The aim of the study was to establish how much candidates remembered about their test in order to assess the potential for collusion. Eighty-nine candidates were asked immediately after testing what they remembered about their ALS scenario. Recall of the underlying problem with the simulated patient was good (85 [96%]). Forty-two [47%] correctly remembered the initial cardiac arrest rhythm and 55 [61%] the subsequent cardiac arrest rhythm. Fifty-nine [60%] candidates passed the assessment. Candidates who passed the assessment were significantly more likely to correctly recall the initial and subsequent cardiac arrest rhythms than those who did not. However, even in this group, the overall recall of all elements of the scenario was correct in only 49% of instances. This study demonstrated that immediately after testing candidates had good recall of the initial clinical scenario with which they were presented, but poor recall of cardiac arrest rhythms during the simulated resuscitation attempt. These findings provide some reassurance that the likelihood of successful collusion improving subsequent candidates performance is likely to be small as recall of the scenario progression is limited.

Gut dysfunction and endoscopic lesions after out-of-hospital cardiac arrest

Background: Cardiac arrest induces severe mesenteric ischaemia. The objective of this study was to assess the frequency of gut dysfunction and endoscopic lesions following resuscitation after cardiac arrest, and to evaluate the potential value of gut endoscopy performance in these circumstances. Methods: This is a retrospective data files survey of 3617 patients from the database in a medical intensive care unit. A systematic review of medical and endoscopic files was performed within this database, using a standardised chart. Patients: One-hundred and thirty consecutive patients who survived up to 48 h were admitted to our unit after out-of-hospital cardiac arrest. Seventy-eight of these patients (60%) presented with early clinical signs of gut dysfunction and/or lesions. Thirty-six patients underwent gut endoscopies (26%) and were included in the survey. Results: Endoscopic lesions were observed in all cases; in 15 cases, gastrointestinal haemorrhage requiring intervention was identified. The occurrence of haemorrhagic and/or necrotic lesions was found to be associated with an initial rhythm of asystole, higher SAPS II values and epinephrine requirements, compared with cardiac arrest patients without such lesions. Conclusion: The frequent occurrence of endoscopic lesions in the presence of gut dysfunction following a cardiac arrest could suggest systematic gut endoscopy in such patients. However, an alternative recommendation would be to watch these patients very closely, treat all with prophylactic proton pump inhibitors, and endoscope only those with evidence of bleeding.

Use of implantable cardioverter defibrillators after out-of-hospital cardiac arrest: a prospective follow-up study

Survivors of out-of-hospital cardiac arrest are at high risk of recurrent arrests, many of which could be prevented with implantable cardioverter defibrillators (ICDs). We sought to determine the ICD insertion rate among survivors of out-of-hospital cardiac arrest and to determine factors associated with ICD implantation. The Ontario Prehospital Advanced Life Support (OPALS) study is a prospective, multiphase, before-after study assessing the effectiveness of prehospital interventions for people experiencing cardiac arrest, trauma or respiratory arrest in 19 Ontario communities. We linked OPALS data describing survivors of cardiac arrest with data from all defibrillator implantation centres in Ontario. From January 1997 to April 2002, 454 patients in the OPALS study survived to hospital discharge after experiencing an out-of-hospital cardiac arrest. The mean age was 65 (standard deviation 14) years, 122 (26.9%) were women, 398 (87.7%) had a witnessed arrest, 372 (81.9%) had an initial rhythm of ventricular tachycardia or ventricular fibrillation (VT/VF), and 76 (16.7%) had asystole or another arrhythmia. The median cerebral performance category at discharge (range 1-5, 1 = normal) was 1. Only 58 (12.8%) of the 454 patients received an ICD. Patients with an initial rhythm of VT/VF were more likely than those with an initial rhythm of asystole or another rhythm to undergo device insertion (adjusted odds ratio [OR] 9.63, 95% confidence interval [CI] 1.31-71.50). Similarly, patients with a normal cerebral performance score were more likely than those with abnormal scores to undergo ICD insertion (adjusted OR 12.52, 95% CI 1.74-92.12). A minority of patients who survived cardiac arrest underwent ICD insertion. It is unclear whether this low usage rate reflects referral bias, selection bias by electrophysiologists, supply constraint or patient preference.

Cardiopulmonary resuscitation of adults in the hospital: a report of 14720 cardiac arrests from the National Registry of Cardiopulmonary Resuscitation.

The National Registry of Cardiopulmonary Resuscitation (NRCPR) is an American Heart Association (AHA)-sponsored, prospective, multisite, observational study of in-hospital resuscitation. The NRCPR is currently the largest registry of its kind. The purpose of this article is to describe the NRCPR and to provide the first comprehensive, Utstein-based, standardized characterization of in-hospital resuscitation in the United States. All adult (>/=18 years of age) and pediatric (<18 years of age) patients, visitors, employees, and staff within a facility (including ambulatory care areas) who experience a resuscitation event are eligible for inclusion in the NRCPR database. Between January 1, 2000, and June 30, 2002, 14720 cardiac arrests that met inclusion criteria occurred in adults at the 207 participating hospitals. An organized emergency team is available 24 h a day, 7 days a week in 86% of participating institutions. The three most common reasons for cardiac arrest in adults were (1) cardiac arrhythmia, (2) acute respiratory insufficiency, and (3) hypotension. Overall, 44% of adult in-hospital cardiac arrest victims had a return of spontaneous circulation (ROSC); 17% survived to hospital discharge. Despite the fact that a primary arrhythmia was one of the precipitating events in nearly one half of adult cardiac arrests, ventricular fibrillation (VF) was the initial pulseless rhythm in only 16% of in-hospital cardiac arrest victims. ROSC occurred in 58% of VF cases, yielding a survival-to-hospital discharge rate of 34% in this subset of patients. An automated external defibrillator was used to provide initial defibrillation in only 1.4% of patients whose initial cardiac arrest rhythm was VF. Neurological outcome in discharged survivors was generally good. Eighty-six percent of patients with Cerebral Performance Category-1 (CPC-1) at the time of hospital admission had a postarrest CPC-1 at the time of hospital discharge.

Avoiding the futility of resuscitation

Purpose: To identify patients who should not have resuscitation started or continued. Design: Multi-disciplinary prospective study. Subjects: Two hundred forty-one consecutive patients with cardiopulmonary arrests from January 1995 to February 1997 were evaluated, of which 200 were studied. Methods: Subjects were studied for age, sex, arrest location, CPR duration, recovery from arrest, hospital discharge, 6 weeks' survival, sepsis and co-morbid conditions. Results: Overall 69 (34.5%) recovered from the arrest, 24 (12.0%) left the hospital, and 17 (8.5%) survived 6 weeks. Of inpatients, 13.7% (16/117) were alive at 6 weeks in contrast to 1.2% (1/83) of field/emergency room (ER) arrests. Sepsis did not lessen the immediate recovery rate; however, none of 25 septic patients survived hospitalization. Outcomes were not different between men and women or regular floor and ICU/CCU arrests. Age of survivors was the same as non-survivors. Survivors were resuscitated for 18.7±16.5 min and non-survivors 33.1±18.4 min ( P=0.15). The initial rhythm of asystole or the presence of three or more co-morbid conditions had a negative prognosis. Conclusion: CPR survival is problematic, and it is especially poor in field/BR arrests. Emergency squads should terminate CPR for pulseless patients after communicating with the ER physician. Age is not a determinant of recovery or survival. Arrest outside of the hospital, sepsis, three or more co-morbid conditions, previous CPR, asystole or resuscitation for >25 min all decrease the chance of hospital discharge and survival. Instituting or continuing CPR in a great majority of these patients is futile. Families should be so advised.

Factors affecting survival after prehospital asystolic cardiac arrest in a Basic Life Support-Defibrillation system

Previous studies have shown a low but meaningful survival rate in cases of prehospital cardiac arrest with an initial rhythm of asystole. There may be, however, an identifiable subgroup in which resuscitation efforts are futile. This study identified potential field criteria for predicting 100% nonsurvival when the presenting rhythm is asystole in a Basic Life Support-Defibrillation (BLS-D) system. This prospective cohort study, a component of Phases I and II of the Ontario Prehospital Advanced Life Support (OPALS) Study, was conducted in 21 Ontario communities with BLS-D level of care, and included all adult arrests of presumed cardiac etiology according to the Utstein Style Guidelines. Analyses included descriptive and appropriate univariate tests, as well as multivariate stepwise logistic regression to determine predictors of survival. From 1991 to 1997, 9899 consecutive cardiac arrest cases with the following characteristics: male (67.2%), bystander-witnessed (44.7%), bystander CPR (14.2%), call response interval (CRI) </= 8 minutes (82%) and overall survival (4.3%) were enrolled. Of 9529 cases with available rhythm strip recordings, initial arrest rhythms were asystole in 40.8%, pulseless electrical activity in 21.2% and ventricular fibrillation or ventricular tachycardia in 38%. Of 3888 asystolic patients, 9 (0.2%) survived to discharge; 3 of these cases were unwitnessed arrests with no bystander CPR. There were no survivors if the CRI exceeded 8 minutes. Logistic regression analysis demonstrated that independent predictors of survival to admission were "CRI in minutes" (odds ratio [OR] = 0.87; 95% confidence interval [CI], 0.77-0.98) and "bystander-witnessed" (OR = 2.6; 95% CI, 1.5-4.4). In a BLS-D system, there is a very low but measurable survival rate for prehospital asystolic cardiac arrest. CRIs of over 8 minutes were associated with 100% nonsurvival, whereas unwitnessed arrests with no bystander CPR were not. These data add to the growing literature that will help guide ethical decision-making for protocol development in emergency medical services systems.

Circadian variation in sudden cardiac death: Effects of age, sex, and initial cardiac rhythm: Ann Emerg Med 1996; 27/1: 29–34

Abstract Study objective: Previous studies based on data obtained from vital statistics records have demonstrated circadian variation in the occurrence of sudden cardiac death. The purpose of this study was to examine the effects of age, sex, and initial cardiac rhythm on circadian variability in sudden cardiac death. Methods: This study employed a retrospective analysis of the records of adult patients with witnessed cardiac arrest who underwent resuscitation in an urban paramedic system during a 5-year period. Results: The records of 2,250 consecutive patients with witnessed cardiac arrest were reviewed. Spectral analysis was used to decompose the data into frequency components. A circadian variation in the occurrence of sudden cardiac death was demonstrated, with a low occurrence rate between midnight and 6 AM and a 2.4-fold increase between the rate at 6 AM and the rate at noon. The same circadian pattern was noted among both men and women, among both patients aged 18 to 70 and those older than 70 years, and among patients with various initial cardiac arrest rhythms (ventricular tachycardia or fibrillation, asystole, and electromechanical dissociation). However, the outcome of resuscitation in these patients (ie, the rate of successful resuscitation and the rate of survival) did not demonstrate circadian variation. Conclusion: Witnessed out-of-hospital sudden cardiac death demonstrated circadian variation, and this variability was observed regardless of the patient's age, sex, or initial cardiac arrest rhythm. The outcome of resuscitation did not show circadian variability. These results suggest a common pathophysiologic mechanism leading to sudden cardiac death. [Thakur RK, Hoffmann RG, Olson DW, Joshi R, Tresch DD, Aufderheide TP, Ip JH: Circadian variation in sudden cardiac death: Effects of age, sex, and initial cardiac rhythm. Ann Emerg Med January 1996;27;29-34.]

Circadian Variation in Sudden Cardiac Death: Effects of Age, Sex, and Initial Cardiac Rhythm

Study objective: Previous studies based on data obtained from vital statistics records have demonstrated circadian variation in the occurrence of sudden cardiac death. The purpose of this study was to examine the effects of age, sex, and initial cardiac rhythm on circadian variability in sudden cardiac death. Methods: This study employed a retrospective analysis of the records of adult patients with witnessed cardiac arrest who underwent resuscitation in an urban paramedic system during a 5-year period. Results: The records of 2,250 consecutive patients with witnessed cardiac arrest were reviewed. Spectral analysis was used to decompose the data into frequency components. A circadian variation in the occurrence of sudden cardiac death was demonstrated, with a low occurrence rate between midnight and 6 AM and a 2.4-fold increase between the rate at 6 AM and the rate at noon. The same circadian pattern was noted among both men and women, among both patients aged 18 to 70 and those older than 70 years, and among patients with various initial cardiac arrest rhythms (ventricular tachycardia or fibrillation, asystole, and electromechanical dissociation). However, the outcome of resuscitation in these patients (ie, the rate of successful resuscitation and the rate of survival) did not demonstrate circadian variation. Conclusion: Witnessed out-of-hospital sudden cardiac death demonstrated circadian variation, and this variability was observed regardless of the patient's age, sex, or initial cardiac arrest rhythm. The outcome of resuscitation did not show circadian variability. These results suggest a common pathophysiologic mechanism leading to sudden cardiac death. [Thakur RK, Hoffmann RG, Olson DW, Joshi R, Tresch DD, Aufderheide TP, Ip JH: Circadian variation in sudden cardiac death: Effects of age, sex, and initial cardiac rhythm. Ann Emerg Med January 1996;27;29-34.]

In-hospital cardiopulmonary resuscitation: prospective survey of management and outcome.

A sixteen-month prospective survey of in-hospital cardiac arrests indicated that of 168 patients who received cardiopulmonary resuscitation, 27 (16%) survived to leave hospital. Ninety-three per cent of these patients were ambulant and 81% were able to care for themselves. Poorest outcome was associated with initial rhythm of asystole, prolonged resuscitation and arrest in the Intensive Care Units. When compared with recent and past literature, these figures suggest that the incidence of successful outcome for cardiopulmonary resuscitation in hospitals has not changed significantly over the past twenty years.

Atropine in asystole: Human studies

Current research supporting the use of atropine for asystole is limited. Reported in the literature are the cases of 26 patients who presented with a rhythm of asystole. Of these, only eight were clearly in refractory asystole after epinephrine and sodium bicarbonate, only seven were prehospital patients, and only two were delineated as being intubated. Despite such limited data, atropine has been advocated for asystole, and use of the drug is included in the recommendations of the American Heart Association. We undertook a retrospective review of our prehospital experience with refractory asystole for a four-year period from January 1979 to December 1982. All patients with trauma or poisoning and all pediatric arrests were excluded. All patients who received calcium chloride during resuscitation also were excluded. One hundred seventy patients presented in cardiorespiratory arrest with an initial rhythm of asystole. Of these, 84 remained in refractory asystole after receiving epinephrine and sodium bicarbonate. Forty-three patients in this group received atropine. The successful resuscitation rate in the atropine group was 14% (6/43), while in the control group it was 0% (0/41) (P less than .04). A successful resuscitation was defined as conveyance of a patient with a rhythm and a pulse to an emergency department. Patients were compared for age, sex, witnessing of arrest, cardiac history, and cardiac drugs. No other significant differences were noted between groups. No patient who received atropine for refractory asystole was discharged alive.