Cardiac arrest in the Emergency Medical Service System: guidelines for resuscitation

Predictive performances of ALS and BLS termination of resuscitation rules in out-of-hospital cardiac arrest for different resuscitation protocols

BACKGROUND

Resuscitation guidance has advanced; however, the predictive performance of the termination of resuscitation (TOR) rule has not been validated for different resuscitation protocols published by the American Heart Association (AHA).

METHODS

A retrospective study validating the basic life support (BLS) and advanced life support (ALS) TOR rules was conducted using an Utstein-style database in Tainan city, Taiwan. Adult patients with nontraumatic out-of-hospital cardiac arrests from January 1, 2015, to December 31, 2015, (using the AHA 2010 resuscitation protocol) and from January 1, 2020, to December 31, 2020, (using the AHA 2015 resuscitation protocol) were included. The characteristics of rule performance were calculated, including sensitivity, specificity, positive predictive value (PPV) and negative predictive value.

RESULTS

Among 1260 eligible OHCA patients in 2015, 757 met the BLS TOR rule and 124 met the ALS TOR rule. The specificity and PPV for predicting unfavorable neurological outcomes were 61.1% and 99.0%, respectively, for the BLS TOR rule and 93.8% and 99.2%, respectively, for the ALS TOR rule. A total of 970 OHCA patients were enrolled in 2020, of whom 438 met the BLS TOR rule and 104 met the ALS TOR rule. The specificity and PPV for predicting unfavorable neurological outcomes were 85.7% and 100%, respectively, for the BLS TOR rule and 99.5% and 100%, respectively, for the ALS TOR rule.

CONCLUSIONS

Both the BLS and ALS TOR rules performed better when using the 2015 AHA resuscitation protocols compared to the 2010 protocols, with increased PPVs and decreased false-positive rates in predicting survival to discharge and good neurological outcomes at discharge. The BLS and ALS TOR rules can perform differently while the resuscitation protocols are updated. As the concepts and practices of resuscitation progress, the BLS and ALS TOR rules should be evaluated and validated accordingly.

The Death Watch: Certifying Death Using Cardiac Criteria

In the past, inadequate diagnostic instruments sometimes led to incorrect diagnoses of death, so careful and prolonged observation—the “death watch”—was required. Diagnostic instruments are now accurate and determining the presence or absence of circulation and cerebral function is easy in virtually all cases. Still, ambiguity and controversy in diagnosing death persists because the current criteria, irreversible cessation of cardiac or whole brain function, are ambiguous. Recent reintroduction of Non—Heart-beating organ donation has highlighted the controversy. Data on the ability to achieve restoration of spontaneous circulation are quite consistent, but they support several different sets of reasonable death criteria. This article concludes with a rejection of a fixed notion of “irreversibility” because it does not conform to current practice, is potentially deleterious to social events at the time of death, and the reversibility of cardiopulmonary arrest is dependent on available means of resuscitation. Finally, the time required to ensure irreversible cessation of cardiac function despite potential intervention is too broad to be clinically applicable and is unreasonable. Diagnosis of death should be based on the context in which it occurs because the medical means available determine what is irreversible.

Variability in the determination of death after cardiac arrest: a review of guidelines and statements

INTRODUCTION

The reemergence of organ donation after circulatory determination of death (DCDD) in Canada demands the establishment of clear, evidence-based guidelines for the determination of death. The primary purpose of this study was to investigate the variability in specific criteria, diagnostic tests, and recommended wait periods for the determination of death after cardiac arrest.

METHODS

We used PubMed and Web of Science to perform a structured search of the medical literature for articles published up to January 1, 2010. We also performed an unstructured search of the internet for unrestricted, readily available, nonjournal sources. We limited the search to countries that are most active in DCDD.

RESULTS

A total of 26 documents were retrieved; 21 medical professional society/institution statements and 5 national/international guidelines. Specific criteria for the determination of death after cardiac arrest were cited in 24 documents: 14 recommend cardiocirculatory criteria alone; 6 oblige the requirement of a prolonged waiting period after declaration to ensure neurological death; 3 recommend following "accepted medical practice" without specific details; and 1 leaves the definition up to "national authorities." Only 16 of the documents require specific diagnostic procedures with unresponsiveness, absent arterial pulse and apnea cited the most consistently. Specific wait periods after declaration are required for the determination of death after cardiac arrest in 24 documents, cited times range from 2 to 10 minutes, with a 5-minute period the most frequent.

CONCLUSIONS

This review is the first to document the variability of guidelines and statements for the determination of death after cardiac arrest, in countries where the practice of DCDD is becoming increasingly common. The scarcity of peer-reviewed published guidelines in the medical literature exemplifies the need for further investigation. We believe these results will inform the ethical discussions surrounding the determination of death after cardiac arrest. Clear and consistent guidelines based on evidence are needed to fulfill medical, ethical, and legal obligation and to ensure public trust.

Transfer of care is associated with longer unsuccessful resuscitations

OBJECTIVE

Accepted guidelines define when to terminate unsuccessful resuscitations. We examined whether such resuscitations last longer for transported arrests in the field compared with those occurring in the emergency department (ED).

METHODS

This was a retrospective study of patients who died in an urban, academic ED over 32 months starting from January 2001. Total length of resuscitation and the interval occurring in-ED were compared for arrests in the ED and transported arrests from the field.

RESULTS

A total of 132 patients met the criteria, of whom 71 (53.8%) arrested in the field. Mean overall resuscitation times were longer for arrests occurring in the field (44 minutes; 95% confidence interval [CI], 39-48) compared with those in the ED (19 minutes; 95% CI, 16-22; P < .001). Mean resuscitation intervals occurring in the ED were no different for arrests occurring in the field (16 minutes; 95% CI, 13-19) than in the ED (19 minutes; 95% CI, 16-22; P > .05).

CONCLUSIONS

Unsuccessful resuscitations were longer and beyond guideline recommendations when arrests occurred in the field and were transported. The interval of resuscitation that occurred in the ED was the same whether or not prehospital resuscitation occurred.

Recognition of death and termination of cardiac resuscitation attempts by UK ambulance personnel

OBJECTIVES

To identify whether the practice of the UK ambulance trusts comply with national recommendations with respect to when ambulance personnel are allowed to recognise death and/or terminate resuscitation attempts in the adult, normothermic, non-traumatic cardiac arrest.

METHODS

Questionnaire study of 39 ambulance trusts.

RESULTS

At the time of the study (summer 2000), 23 trusts operated separate policies for recognition of death and termination of resuscitation, two had policies for recognition of death alone, two had policies for termination of resuscitation alone, five operated a policy purely for termination of resuscitation attempts after a limited period of CPR, and seven had no protocols other than "the presence of rigor mortis, postmortem staining or injuries incompatible with life". Only eight trusts conformed to the protocols for both recognition of death and termination of resuscitation attempts recommended by the Joint Royal Colleges Ambulance Liaison Committee (JRCALC).

CONCLUSION

The JRCALC has proposed guidelines for recognition of death and terminating resuscitation attempts in the adult normothermic non-traumatic cardiac arrest. Despite this, there was still considerable variance in the practice of the UK ambulance trusts.

Resuscitation research: future directions and ethical issues

Cardiopulmonary resuscitation research is a vital area of research that has made significant contributions to medical care over the last several decades. Abundant information currently exists in the medical literature, as a result of research in the areas of cardiac arrest and outcomes, physiology of cardiac arrest, pharmacologic treatments, mechanical interventions, and societal and ethical issues. Despite numerous clinical trials demonstrating physiologic benefit of various interventions, few interventions have had as much impact on outcomes of cardiac arrest as have improvements in out-of-hospital response times and rapid availability of medical treatment. Although abundant information exists regarding physiologic aspects of resuscitation, relatively little information exists about ethical, psychological, and social aspects of resuscitation. In addition to attempts to improve outcomes of cardiac arrest, researchers should also strive to improve the experiences of patients and families involved. These realities provide future strategies and directions for the best use of resuscitation research resources; although physiologic and pharmacologic research will always have significant roles in the improvement of medical care, the rapid delivery of out-of-hospital care and ethical issues will be indispensable areas of research focus in the future.

Decision making by emergency physicians when assessing cardiac arrest patients on arrival at hospital

OBJECTIVE

To investigate the factors which influence decision making by experienced emergency physicians when they decide whether to (a) pronounce 'life extinct' in adult patients with non traumatic cardiac arrest while in the ambulance, or (b) bring them into the resuscitation room in the Emergency Department for further assessment/management.

DESIGN

Qualitative study involving semi structured interviews and a focus group.

SETTING

Accident & Emergency (A&E) departments in the Yorkshire region.

PARTICIPANTS

Fifteen emergency physicians (two clinical fellows, nine specialist registrars and four consultants) working in the Yorkshire region.

RESULTS

Six main themes were identified that impacted upon the decision making process: the doctor's past experience, ambulance service issues, prehospital care, patient characteristics, presence and views of relatives, and organisational issues.

CONCLUSION

The reasoning behind decisions made when a patient arrives at the Emergency Department in cardiac arrest is multifactorial. Strict guidelines would be difficult to construct since individuals vary in the importance they attach to different factors.

The death watch: certifying death using cardiac criteria

In the past, inadequate diagnostic instruments sometimes led to incorrect diagnoses of death, so careful and prolonged observation--the "death watch"--was required. Diagnostic instruments are now accurate and determining the presence or absence of circulation and cerebral function is easy in virtually all cases. Still, ambiguity and controversy in diagnosing death persists because the current criteria, irreversible cessation of cardiac or whole brain function, are ambiguous. Recent reintroduction of non-heart-beating organ donation has highlighted the controversy. Data on the ability to achieve restoration of spontaneous circulation are quite consistent, but they support several different sets of reasonable death criteria. This article concludes with a rejection of a fixed notion of "irreversibility" because it does not conform to current practice, is potentially deleterious to social events at the time of death, and the reversibility of cardiopulmonary arrest is dependent on available means of resuscitation. Finally, the time required to ensure irreversible cessation of cardiac function despite potential intervention is too broad to be clinically applicable and is unreasonable. Diagnosis of death should be based on the context in which it occurs because the medical means available determine what is irreversible.

Ethical issues of resuscitation

There is a wide variety of ethical issues and dilemmas involving resuscitation, the act of restoring life to a patient in cardiorespiratory arrest. Decisions must be made rapidly and often must be based on suboptimal levels of information available at the time. Certain issues should be considered when one is making decisions in the resuscitation arena, including positive-aspects of resuscitation, not only the possibility of restoring life to the patient but also providing a sense of closure and resolution of guilt for the survivors. During and following resuscitative efforts, the psychologic and emotional well-being of the survivors should also be given close attention.

Predicting in-hospital mortality during cardiopulmonary resuscitation

On the average, 10-15% of patients who undergo cardiopulmonary resuscitation (CPR) following a cardiopulmonary arrest in the hospital environment will survive to be discharged. The purpose of this study was to determine objective factors influencing patient outcome after CPR to determine who should be resuscitated and when to end CPR efforts. The records of 266 patients who underwent in-hospital CPR over a 3-year period were retrospectively analyzed with regard to age, gender, co-morbid conditions, setting of arrest, duration of resuscitation, initial pH and PO2 during resuscitation, and outcome of resuscitative efforts. Twenty-four (9%) patients survived to be discharged from hospital. Eighty-seven (33%) patients arrested in the intensive care unit, 77 (29%) on the ward, 91 (34%) in the emergency room, six (2%) in the cardiac catheterization laboratory and five (2%) in the operating room. There was no significant difference in survival based on location of arrest. Factors associated with a poor prognosis included age greater than 60, co-morbid disease (i.e. pneumonia, sepsis, renal failure, heart disease, etc.), an initial PO2 < 50 mmHg and CPR efforts extending beyond 10 min. Based on this data, guidelines regarding initiation and termination of CPR should be instituted in light of poor outcome in patients over 60 years of age with co-morbid conditions, specifically after 10 min of CPR.

Decision making in resuscitation from out of hospital cardiac arrest

OBJECTIVE

To determine which factors are perceived by senior house officers (SHOs), consultants, and medical registrars in accident and emergency (A&E) medicine as being important in decision making.

METHODS

132 SHOs in A&E medicine, of 172 attending an induction course at the start of their job (77%), completed a questionnaire relating to 20 factors of possible importance in decision making; 73 completed the questionnaire at six weeks and 55 at six months. Ten medical registrars and 31 consultants in A&E medicine also completed the questionnaire.

RESULTS

The SHOs were able to recognise bystander cardiopulmonary resuscitation and early advanced I support, as well as the presence of ventricular fibrillation, as important prognostic factors. There was considerable variation in all three groups in their opinions on the importance of the other factors considered. There was no obvious change in SHO responses over the period of training.

CONCLUSIONS

Lack of guidelines may result in more patients receiving resuscitation than are salvageable, as doctors maintain a low threshold for continuing resuscitation to avoid missing potential survivors. A decision making algorithm is recommended.

Family response to out-of-hospital death

OBJECTIVE

To better understand the perceptions, needs, and responses of family members after an out-of-hospital death.

METHODS

Over an 18-month period, phone interviews were conducted using a structured interview schedule modified from a similar study of survivors of in-hospital death. Subjects included 31 survivors of urban out-of-hospital deaths attended by paramedics from one ambulance company. Subjects were eligible if paramedics had arrived and death had been determined at the scene without transport. Survivors were interviewed 11 to 15 months after the death (mean = 12 months) to evaluate how well they coped with their loss, how they managed the experience of their loved ones' out-of-hospital deaths, and their feelings and beliefs about their loved ones' not being transported to a hospital.

RESULTS

None of the survivors believed their loved ones should have been transported to a hospital, and only one believed that something more could have been done for the individual. Although many of the survivors had suspected their loved ones had died, 64% had been informed of the death by emergency medical technicians (EMTs) or firefighters. Most thought the EMTs had informed them in a professional (81%) and gentle/supportive manner (74%). Some (29%) still had unanswered questions about the death, but most (58%) were adjusting well and no one had a "poor" adjustment.

CONCLUSION

In this small sample, survivors of out-of-hospital death were generally satisfied with the care their loved ones had received. None of the survivors believed their loved ones should have been transported to the hospital. They also believed the paramedics had been supportive and met their needs at the time of death. It appears that paramedics may be able to meet the needs of a patient's survivors by terminating out-of-hospital resuscitation efforts on the patient.

A simplified prehospital advance directive law: Arizona's approach

Many of the approximately 400,000 deaths that occur outside of hospitals or chronic care facilities each year in the United States are not only expected but also welcomed as relief from terminal disease. However, patients who lack decision-making capacity cannot communicate to emergency medical services system and emergency department personnel their wish not to be the recipient of advanced life support procedures. Prehospital advance directives (PHAD) offer that opportunity. Arizona is only the fourth state to pass a PHAD statute and the first to simplify the law so it is interpreted easily by both providers and patients. PHAD laws need not be complex, either in their language or in their implementation requirements. Simple and easily understood statues and their resulting directives increase the likelihood that those most likely to need and use this directive will be able to comply with its provisions. Arizona's law addresses several controversial areas yet to be worked out by other states. Placing the PHAD in statute ensures that a statewide attempt will be made to comply with its provisions, and as a law it should be more permanent than advance directive protocols based on administrative fiat. Physicians in other states may want to follow Arizona's lead and employ a joint effort by their state's bar association, hospital association, and medical association to smooth the passage of similar legislation. All parties involved, however, must not seek a perfect statute. Arizona's experience suggests that legislators will need to strike a balance between the needs of the citizens and the fears of lawyers wary of any potential liability for the state or the emergency medical services system.

Criteria for dead-on-arrivals, prehospital termination of CPR, and do-not-resuscitate orders

In contrast to the current consensus that governs the mechanics of prehospital advanced cardiac life support (ACLS), uniform criteria for determining when to initiate, withhold, or terminate ACLS in the field do not exist. Most emergency medical services (EMS) permit paramedics and other prehospital providers to withhold resuscitation when the victim obviously is dead, but the accuracy and appropriateness of this judgement in the field have not been subjected to empiric research. Do-not-resuscitate orders on patients in community settings often are problematic when paramedics and other prehospital providers are governed by standing orders that require them to initiate CPR when it is indicated medically. To date, eight states and a number of local EMS systems have developed a variety of policies to address this dilemma. Currently, few services permit paramedics to terminate ACLS in the field when such efforts fail to achieve return of spontaneous circulation. Studies have demonstrated convincingly that the rapid transport of such patients for further attempts at resuscitation in the hospital yields dismal rates of survival. The costs, risks, and benefits of this practice in community settings must be reviewed carefully to allocate EMS resources in an optimal manner.

Survival rates from out-of-hospital cardiac arrest: recommendations for uniform definitions and data to report

Survival rates for out-of-hospital cardiac arrest vary widely among locations. We surveyed the definitions used in published studies of out-of-hospital cardiac arrest. Data from 74 studies involving 36 communities showed survival rates ranging from 2% to 44%. There were five different case definitions and 11 different definitions of survivors. The absence of uniform definitions prevents meaningful intersystem comparisons, prohibits explorations of hypotheses about effective interventions, and interferes with the efforts of quality assurance. The most satisfactory numerator for a survival rate appears to be survival to hospital discharge; the most appropriate denominator appears to be witnessed adult cardiac arrest of presumed heart disease etiology, with ventricular fibrillation as the initial identified rhythm. Proposed definitions for the data emergency medical services systems should report as they examine their cardiac arrest survival rates are presented.

Outcomes in unsuccessful field resuscitation attempts

To determine the outcomes of patients who did not regain vital signs after prehospital advanced cardiac life support, we studied adult patients who sustained nontraumatic out-of-hospital cardiac arrest. Our study consisted of a 20-month retrospective review of 244 charts beginning January 1986. Twelve patients were excluded for drug overdose, family request, or unavailable data. Of the remaining 232 patients, 51 had a rhythm and pulse on arrival at the emergency department. The record of each of the remaining 181 patients was analyzed for age, sex, location, witness, CPR initiator, advanced life support unit response time, initial field rhythm, and initial ECG rhythm. Outcome alternatives were dead in emergency department or hospital admission. All hospitalized patients were further evaluated for survival to discharge and neurologic status at discharge. Ten of the 181 patients (6%) who failed prehospital resuscitation survived to hospitalization, and one (0.6%) was discharged neurologically intact. Survival to hospital admission did not correlate with any of the variables studied except gender. The one patient who survived a failed prehospital resuscitation was not endotracheally intubated in the field. Our data support the practice of pronouncing adult nontraumatic cardiac arrest victims who fail to respond to advanced cardiac life support efforts in the field as dead at the scene.

Pre-CPR conditions and the final outcome of CPR. The Cerebral Resuscitation Study Group

Outcome of cardiac arrest (CA) is very much influenced by pre-CPR conditions. To assess the importance of these pre-CPR factors, an analysis of the Belgian CPCR registry was made according to some pre-CPR conditions. In this registry, several variables related to pre-arrest, arrest, CPR and post CPR period have been recorded in 4548 patients. The pre-CPR conditions studied were: age, witnessed event or not, pre-arrest health state, underlying disease, site of cardiac arrest, type of respiratory arrest and type of cardiac arrest. Age did not influence outcome significantly. The importance of witnessing is very significant. Severe pre-arrest disability reduces chances on long-term survival (LTS) to half and overall health status longterm survivors is clearly less. Intoxication and metabolic origin of CA have good prognosis (LTS, 21%). Trauma/exsanguination, drowning, SIDS and sepsis have bad prognosis (LTS, 1-3%). Cardiac (LTS, 12%) and respiratory (LTS, 14%) origin have similar outcome, although significant difference exists in occurrence of cerebral failure, suggesting that post-ischemic encephalopathy is more severe in respiratory than in cardiac origin. The most frequent site of CA, the home of the patient, has poor outcome results (LTS, 5%). Gasping is significantly related to successful outcome. In the out-of-hospital setting the type of CA was 25% VF (LTS, 77%), 65% asystole (LTS, 4%) and 10% EMD (LTS, 3%). Outcome of the subgroup out-of-hospital, witnessed, VF is comparable to other reports. This sub-group seems to us the most appropriate for clinical trials.

Out-of-hospital cardiac arrest: the teaching of experience at the SAMU of Lyon

Because of the improvement resuscitation techniques have shown since the 1960s and because of the development of the out-of-hospital medical care, a cardiac arrest is no longer synonymous with death in every case. However the cardiac arrest resuscitation is only relevant if its adverse consequences can be limited. That is mainly the neurological after-effects and the cellular anoxia. Therefore, the "Service d'Aide Medicale Urgente" (SAMU) of Lyon has been concentrating its research aiming at: (a) Shortening the duration of cardiopulmonary resuscitation to limit the cerebral anoxia. (b) Analysing and treating some of the causes responsible for the aggravation of anoxia. On the basis of several studies in Lyon, here are some suggestions: (1) The use of high doses of epinephrine that unables a better percentage of primary recoveries (47.5% vs. 39%) (P less than 0.05) and secondary recoveries (21.3% vs. 14.8%) (P less than 0.01) without modifying the qualitative survival at long term. (On the basis of: 5 mg intravenous bolus repeated every 3 min in case of asystole instead of 1 mg every 5 min as it is usually recommended). (2) The choice of a peripheral intravenous line instead of a central intravenous line each time it is possible for the administration of drugs since it is as efficient as the second one. (40.7% vs. 33.4%) (P:NS). (3) The alkalinisation of the prolonged cardiac arrest in order to keep the acid-base balance. Most of the survivors show a pH equal or superior to the normal standard. (On the basis of 1 mmol/kg of sodium bicarbonate if the cardiac arrest lasts for more than 10 min). (4) The abolition of the dextrose solution as maintaining infusion the patients who are in a "coma depasse" (brain death) after the resuscitation have an average glycemia superior to the survivors without after-effects. (19.7 vs. 14.8 mmol/l) (P less than 0.05). (5) The monitoring at once at the hospital of the intra-cranial pressure. It reveals the frequency of high pression at an early stage (superior to 15 mmHg in 51.1% of the cases) and the absence of favourable evolution in case of high intracranial pressure. At the moment the absence of consequences on the ICR of a calcium entry blocker (Nimodipine) is being studied. The first results do not seem to show any improvement of the cerebral survival. (6) The prophylactic treatment of septicemia with intestinal origin since they occur frequently and prove to be fatal.

Use of conjunctival oxygen monitoring in cardiac patients in the emergency unit

Conjunctival oxygen monitoring (PcjO2) measures conjunctival tissue organ. It has proved useful in helping to evaluate hypovolemic multiple trauma patients, carotid artery surgery patients, as well as others. Little has been written about its use during medical resuscitations. This report reviews its accident and emergency department use in 13 cardiac arrest/life-threatening cardiac dysrhythmia patients. Nine patients expired and four patients survived. Accident and emergency department PcjO2 values in the group which expired averaged 6.3. Those patients who survived averaged 35.4. Subjects who maintained PcjO2 values below 20 did not survive. Furthermore, PcjO2 values taken within the first 8 min of accident and emergency department resuscitation appear to indicate outcome. Conjunctival oxygen monitoring may be useful in monitoring critically ill cardiac patients in the accident and emergency department.

Out-of-hospital cardiac arrest: a six-year experience in a suburban-rural system

All out-of-hospital cardiac arrest advanced life support (ALS) trip sheets were collected from January 1980 through December 1985 for this suburban-rural system. Information was extracted according to a uniform reporting format. In our study, 18% of patients with early CPR (less than four minutes) and early ALS (less than ten minutes) survived to hospital discharge, compared with 7% with early CPR and late ALS, 6% with late CPR and early ALS, and 3% with both occurring late. Although 75% of the survivors had ventricular tachyarrhythmias as initial rhythms, bradyasystolic arrests were not uniformly lethal, even with long CPR and ALS times. This study supports the need for early CPR in the prehospital care of potential sudden-death victims. We recommend, with qualification, this reporting format to emergency medical services systems to describe their cardiac arrest experience.

Guidelines for discontinuing prehospital CPR in the emergency department--a review

We provide information that we believe should allow the establishment of rational guidelines for discontinuing, with physician supervision, unsuccessful prehospital CPR. Goldberg has advocated that CPR be terminated only after evidence of brain or cardiac death has persisted for more than one hour of adequately applied advanced CPR. This recommendation was made for inhospital resuscitation and does not reflect the limited capabilities of basic and advanced CPR techniques to sustain life outside the hospital. In addition, White and associates have demonstrated that after resuscitation from prolonged cardiac arrest, cerebral cortical blood flow is reduced severely. This state of hypoperfusion may last up to 18 hours. Because this condition can result in extensive neurologic damage, it may explain the poor survival rates after prolonged resuscitation. We propose that CPR be terminated in the ED when, despite adequate rescue attempts (intubation, defibrillation, IV medications, CCCM en route) by those responding at the scene of cardiac arrest, intrinsic cardiac activity has not been achieved in patients brought to the hospital with asystole or bradyarrhythmia. Additionally patients who have had advanced prehospital CPR for more than 45 minutes without generation of any intrinsic cardiac activity are not resuscitatable by current standard techniques, and CPR may be discontinued. These criteria must not be used for victims of hypothermia before a core temperature of 35 C to 36.1 C is achieved by active core rewarming during CPR. The available data suggest that if these criteria are implemented, many unproductive hospital-based resuscitative efforts can be eliminated without jeopardizing potential survivors.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of clinical CPR studies in Milwaukee and elsewhere in the United States

As we mark the 25th anniversary of the clinical application of closed-chest cardiopulmonary resuscitation (SCPR), it is time to look back and analyze the progress we have made in the resuscitation of sudden death syndrome. Recent studies of SCPR's effectiveness have yielded mixed results, in comparison to early studies that were universally favorable. The continued toll of neurologic injury following SCPR resuscitation, and reinforcement of the importance of defibrillation in resuscitation, stimulate us to find improved forms of SCPR and improved methods of resuscitation delivery in emergency medical systems.

Comparative study of three methods of resuscitation: closed-chest, open-chest manual, and direct mechanical ventricular assistance

Presented are the results of a comparison study of three forms of circulatory support during ventricular fibrillation: closed-chest compression (CCC), open-chest manual compression (OCMC), and direct mechanical ventricular assistance (DMVA). DMVA is a method of circulatory support using a bell-shaped device that is affixed to the heart by apical suction and that alternately compresses and expands the ventricles. CCC produced a cardiac index (CI) of 780 mL/min/m2 (19% of control) with a mean arterial pressure (MAP) of 26 mm Hg (23% of control). Both forms of direct cardiac compression produced higher values. OCMC at 60 compressions per minute (CPM) produced a CI of 2,069 mL/min/m2 (52% of control) with an MAP of 50 mm Hg (45% of control). DMVA at the same rate produced a CI of 2,780 mL/min/m2 (70% of control) with an MAP of 72 mm Hg (65% of control). The values for DMVA at 60 CPM were significantly higher than for OCMC at 60 CPM (P less than .005 for CI, and P less than .0005 for MAP). Changing from standard CCC to DMVA at 90 CPM produced the greatest hemodynamic improvements: MAP increased by 250%, and CI increased by 340%. With DMVA at 90 CPM, the systolic pressure, stroke index, and CI were not statistically different from control, prearrest values.

Organization of resuscitation within the hospital

Current standards for resuscitation in the hospital include special care areas, a mobile resuscitation team, and training of all nurses and physicians in basic life support. The yield is the saving of a substantial number of lives. The expenditure is patient suffering and hospital costs in cases of initial revival and subsequent death after maximal therapy, infliction of thoracic skeletal lesions necessitating prolonged ventilator support, and survival with brain damage. Concern also exists for death from unattended cardiac arrest in a nonmonitored hospital bed or at home after the patient's discharge from the emergency department as a result of the physician's underestimation of the gravity of the symptoms. Recommendations focus on the improvement of information to the primary decision maker, often the inexperienced young house physician; a more comprehensive understanding of the nature of cardiac arrest; contraindications for resuscitation such as terminal illness or low quality of life; and the role of early application of DC countershock. The time is past when the organization of resuscitation in the hospital can be limited to the mechanics of training in artificial ventilation and cardiac massage.

Cerebral cortical perfusion during and following resuscitation from cardiac arrest in dogs

Perfusion of the cerebral cortex during closed chest CPR in dogs, generating systolic pressures of 60 to 70 mmHg, is only 10% of pre-arrest blood flow. In contrast, internal cardiac massage produces normal cortical perfusion rates. Following a 20-min perfusion arrest, during pressure controlled reperfusion, cortical flow rates decay to less than 20% normal after 90 min of reperfusion. This appears to be due to increasing cerebral vascular resistance, and is not due to rising intracranial pressure. The post-arrest cortical hypoperfusion syndrome is prolonged with cortical flow remaining below 20% normal up to 18 hr post arrest. The use of a variety of calcium antagonists, including flunarizine, lidoflazine, verapamil, and Mg2+, immediately post-resuscitation maintains cerebral vascular resistance and cortical perfusion at normal levels. A prospective blind trial of the calcium antagonist lidoflazine following a 15-min cardiac arrest in dogs and resuscitation by internal massage, demonstrates amelioration of neurologic deficit in the early postresuscitation period.

Criteria for cessation of CPR in the emergency department

Specific criteria have been proposed for the cessation of cardiopulmonary resuscitation (CPR) in the emergency department. Using these criteria and others, we developed a survey which was completed by 78 physicians practicing emergency medicine. The physicians surveyed did not make decisions to cease CPR that were consistent with any such criteria which might guide them in clinical decision making. In this survey, the type of residency training, the size of city in which the physician practiced, and the number of years an individual had practiced emergency medicine significantly correlated with how he made the decision to cease CPR. Based on a review of the current literature, and due to the fact that considerable and variable ethical and psychological factors weigh in each clinical circumstance, the authors recommend that no criteria be followed for ceasing CPR.

Out-of-hospital cardiac arrest: a review of major studies and a proposed uniform reporting system

The scientific literature from January 1970 to June 1979 was reviewed for articles reporting outcomes from out-of-hospital cardiac arrest treated by paramedic programs. Only articles appearing in refereed professional journals and reporting 25 or more attempted resuscitations were included. A total of 21 articles from 15 U.S. locations were found. Four separate case definitions were distinguished. Methods and reporting formats varied considerably. Few studies used an experimental or quasi-experimental design, or control or comparison groups. The range of attempted resuscitations varied from 26 to 1.106 patients. Patients admitted to hospital varied between 22 per cent and 65 per cent (mean 38 per cent, S.D. +/- 12.4 per cent). Patients discharged alive varied from 3.5 per cent to 31 per cent (mean 17.2 per cent, S.D. +/- 7.1 per cent). Post discharge survival was either not reported or reported in different formats. A simplified reporting format is proposed using factors known to be associated with successful resuscitation: 1) underlying heart disease etiology; 2) witnessed arrest; 3) cardiac rhythm of ventricular fibrillation/ventricular tachycardia; 4) hospital admission and discharge and, when possible, by time from collapse to initiation of CPR and definitive care. Uniform reporting of outcomes will improve comparability and accurate measurement of the impact of emergency programs on out-of-hospital cardiac arrest.