High-dose adrenaline in adult in-hospital asystolic cardiopulmonary resuscitation: a double-blind randomised trial

2023 American Heart Association Focused Update on Adult Advanced Cardiovascular Life Support: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

Cardiac arrest is common and deadly, affecting up to 700 000 people in the United States annually. Advanced cardiac life support measures are commonly used to improve outcomes. This "2023 American Heart Association Focused Update on Adult Advanced Cardiovascular Life Support" summarizes the most recent published evidence for and recommendations on the use of medications, temperature management, percutaneous coronary angiography, extracorporeal cardiopulmonary resuscitation, and seizure management in this population. We discuss the lack of data in recent cardiac arrest literature that limits our ability to evaluate diversity, equity, and inclusion in this population. Last, we consider how the cardiac arrest population may make up an important pool of organ donors for those awaiting organ transplantation.

The outcomes of cardiopulmonary resuscitation and their predictors during the coronavirus 2019 pandemic in Iran

BACKGROUND

Coronavirus disease 2019 (COVID-19) can negatively affect different healthcare-related outcomes. Nonetheless, there is limited information about its effects on different healthcare-related outcomes. This study aimed at evaluating the outcomes of cardiopulmonary resuscitation (CPR) and their predictors during the COVID-19 pandemic in Iran.

METHODS

This cross-sectional study was conducted on 1253 patients who had undergone CPR in the emergency wards of teaching hospitals in the west of Iran from the beginning of the first wave to the end of the third epidemic wave of COVID-19 in Iran, between February 20, 2020, and January 20, 2021. Data were collected using the National CPR Documentation Forms developed based on the Utstein Style and routinely used for all patients with cardiac arrest (CA). The SPSS (v. 20.0) program was used to analyze the data through the Chi-square, Fisher's exact, and Mann-Whitney U tests and logistic regression analysis.

RESULTS

Participants' age mean was 64.62 ± 17.54 years. Age mean among participants with COVID-19 was eight years more than other participants. Most participants were male (64.09%) and had at least one underlying disease (64.99%). The total rates of the return of spontaneous circulation (ROSC) and CPR-discharge survival were respectively 15.3% and 3.8% among all participants, 20.25% and 5.17% among participants without COVID-19, and 8.96% and 2.04% among participants with COVID-19. The significant predictors of ROSC were age, affliction by COVID-19, affliction by underlying diseases, baseline rhythm, delay in epinephrine administration, and epinephrine administration time interval, while the significant predictors of CPR-discharge survival were age and baseline rhythm.

CONCLUSIONS

The total rates of ROSC and CPR-discharge survival were respectively 15.3% and 3.8% among all participants. The rates of ROSC and CPR to discharge survival among patients without COVID-19 are respectively 2.26 and 2.53 times more than the rates among patients with COVID-19.

Vasopressors During Cardiopulmonary Resuscitation. A Network Meta-Analysis of Randomized Trials

OBJECTIVES

Several randomized controlled trials have compared adrenaline (epinephrine) with alternative therapies in patients with cardiac arrest with conflicting results. Recent observational studies suggest that adrenaline might increase return of spontaneous circulation but worsen neurologic outcome. We systematically compared all the vasopressors tested in randomized controlled trials in adult cardiac arrest patients in order to identify the treatment associated with the highest rate of return of spontaneous circulation, survival, and good neurologic outcome.

DESIGN

Network meta-analysis.

PATIENTS

Adult patients undergoing cardiopulmonary resuscitation.

INTERVENTIONS

PubMed, Embase, BioMed Central, and the Cochrane Central register were searched (up to April 1, 2017). We included all the randomized controlled trials comparing a vasopressor with any other therapy. A network meta-analysis with a frequentist approach was performed to identify the treatment associated with the highest likelihood of survival.

MEASUREMENTS AND MAIN RESULTS

Twenty-eight studies randomizing 14,848 patients in 12 treatment groups were included. Only a combined treatment with adrenaline, vasopressin, and methylprednisolone was associated with increased likelihood of return of spontaneous circulation and survival with a good neurologic outcome compared with several other comparators, including adrenaline. Adrenaline alone was not associated with any significant difference in mortality and good neurologic outcome compared with any other comparator.

CONCLUSIONS

In randomized controlled trials assessing vasopressors in adults with cardiac arrest, only a combination of adrenaline, vasopressin, and methylprednisolone was associated with improved survival with a good neurologic outcome compared with any other drug or placebo, particularly in in-hospital cardiac arrest. There was no significant randomized evidence to support neither discourage the use of adrenaline during cardiac arrest.

In-Hospital Cardiac Arrest: A Review

IMPORTANCE

In-hospital cardiac arrest is common and associated with a high mortality rate. Despite this, in-hospital cardiac arrest has received little attention compared with other high-risk cardiovascular conditions, such as stroke, myocardial infarction, and out-of-hospital cardiac arrest.

OBSERVATIONS

In-hospital cardiac arrest occurs in over 290 000 adults each year in the United States. Cohort data from the United States indicate that the mean age of patients with in-hospital cardiac arrest is 66 years, 58% are men, and the presenting rhythm is most often (81%) nonshockable (ie, asystole or pulseless electrical activity). The cause of the cardiac arrest is most often cardiac (50%-60%), followed by respiratory insufficiency (15%-40%). Efforts to prevent in-hospital cardiac arrest require both a system for identifying deteriorating patients and an appropriate interventional response (eg, rapid response teams). The key elements of treatment during cardiac arrest include chest compressions, ventilation, early defibrillation, when applicable, and immediate attention to potentially reversible causes, such as hyperkalemia or hypoxia. There is limited evidence to support more advanced treatments. Post-cardiac arrest care is focused on identification and treatment of the underlying cause, hemodynamic and respiratory support, and potentially employing neuroprotective strategies (eg, targeted temperature management). Although multiple individual factors are associated with outcomes (eg, age, initial rhythm, duration of the cardiac arrest), a multifaceted approach considering both potential for neurological recovery and ongoing multiorgan failure is warranted for prognostication and clinical decision-making in the post-cardiac arrest period. Withdrawal of care in the absence of definite prognostic signs both during and after cardiac arrest should be avoided. Hospitals are encouraged to participate in national quality-improvement initiatives.

CONCLUSIONS AND RELEVANCE

An estimated 290 000 in-hospital cardiac arrests occur each year in the United States. However, there is limited evidence to support clinical decision making. An increased awareness with regard to optimizing clinical care and new research might improve outcomes.

Adrenaline and vasopressin for cardiac arrest

BACKGROUND

Adrenaline and vasopressin are widely used to treat people with cardiac arrest, but there is uncertainty about the safety, effectiveness and the optimal dose.

OBJECTIVES

To determine whether adrenaline or vasopressin, or both, administered during cardiac arrest, afford any survival benefit.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase and DARE from their inception to 8 May 2018, and the International Liaison Committee on Resuscitation 2015 Advanced Life Support Consensus on Science and Treatment Recommendations. We also searched four trial registers on 5 September 2018 and checked the reference lists of the included studies and review papers to identify potential papers for review.

SELECTION CRITERIA

Any randomised controlled trial comparing: standard-dose adrenaline versus placebo; standard-dose adrenaline versus high-dose adrenaline; and adrenaline versus vasopressin, in any setting, due to any cause of cardiac arrest, in adults and children. There were no language restrictions.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified trials for review, assessed risks of bias and extracted data, resolving disagreements through re-examination of the trial reports and by discussion. We used risk ratios (RRs) with 95% confidence intervals (CIs) to compare dichotomous outcomes for clinical events. There were no continuous outcomes reported. We examined groups of trials for heterogeneity. We report the quality of evidence for each outcome, using the GRADE approach.

MAIN RESULTS

We included 26 studies (21,704 participants).Moderate-quality evidence found that adrenaline increased survival to hospital discharge compared to placebo (RR 1.44, 95% CI 1.11 to 1.86; 2 studies, 8538 participants; an increase from 23 to 32 per 1000, 95% CI 25 to 42). We are uncertain about survival to hospital discharge for high-dose compared to standard-dose adrenaline (RR 1.10, 95% CI 0.75 to 1.62; participants = 6274; studies = 10); an increase from 33 to 36 per 1000, 95% CI 24 to 53); standard-dose adrenaline versus vasopressin (RR 1.25, 95% CI 0.84 to 1.85; 6 studies; 2511 participants; an increase from 72 to 90 per 1000, 95% CI 60 to 133); and standard-dose adrenaline versus vasopressin plus adrenaline (RR 0.76, 95% CI 0.47 to 1.22; 3 studies; 3242 participants; a possible decrease from 24 to 18 per 1000, 95% CI 11 to 29), due to very low-quality evidence.Moderate-quality evidence found that adrenaline compared with placebo increased survival to hospital admission (RR 2.51, 95% CI 1.67 to 3.76; 2 studies, 8489 participants; an increase from 83 to 209 per 1000, 95% CI 139 to 313). We are uncertain about survival to hospital admission when comparing standard-dose with high-dose adrenaline, due to very low-quality evidence. Vasopressin may improve survival to hospital admission when compared with standard-dose adrenaline (RR 1.27, 95% CI 1.04 to 1.54; 3 studies, 1953 participants; low-quality evidence; an increase from 260 to 330 per 1000, 95% CI 270 to 400), and may make little or no difference when compared to standard-dose adrenaline plus vasopressin (RR 0.95, 95% CI 0.83 to 1.08; 3 studies; 3249 participants; low-quality evidence; a decrease from 218 to 207 per 1000 (95% CI 181 to 236).There was no evidence that adrenaline (any dose) or vasopressin improved neurological outcomes.The rate of return of spontaneous circulation (ROSC) was higher for standard-dose adrenaline versus placebo (RR 2.86, 95% CI 2.21 to 3.71; participants = 8663; studies = 3); moderate-quality evidence; an increase from 115 to 329 per 1000, 95% CI 254 to 427). We are uncertain about the effect on ROSC for the comparison of standard-dose versus high-dose adrenaline and standard-does adrenaline compared to vasopressin, due to very low-quality evidence. Standard-dose adrenaline may make little or no difference to ROSC when compared to standard-dose adrenaline plus vasopressin (RR 0.97, 95% CI 0.87 to 1.08; 3 studies, 3249 participants; low-quality evidence; a possible decrease from 299 to 290 per 1000, 95% CI 260 to 323).The source of funding was not stated in 11 of the 26 studies. The study drugs were provided by the manufacturer in four of the 26 studies, but neither drug represents a profitable commercial option. The other 11 studies were funded by organisations such as research foundations and government funding bodies.

AUTHORS' CONCLUSIONS

This review provides moderate-quality evidence that standard-dose adrenaline compared to placebo improves return of spontaneous circulation, survival to hospital admission and survival to hospital discharge, but low-quality evidence that it did not affect survival with a favourable neurological outcome. Very low -quality evidence found that high-dose adrenaline compared to standard-dose adrenaline improved return of spontaneous circulation and survival to admission. Vasopressin compared to standard dose adrenaline improved survival to admission but not return of spontaneous circulation, whilst the combination of adrenaline and vasopressin compared with adrenaline alone had no effect on these outcomes. Neither standard dose adrenaline, high-dose adrenaline,vasopressin nor a combination of adrenaline and vasopressin improved survival with a favourable neurological outcome. Many of these studies were conducted more than 20 years ago. Treatment has changed in recent years, so the findings from older studies may not reflect current practice.

Cytidine diphosphate choline improves the outcome of cardiac arrest vs epinephrine in rat model

OBJECTIVES

Cytidine diphosphate choline (CDP-choline) is a cholinergic agent that can both stimulate the cholinergic pathway and increase blood pressure. We aimed to investigate the effects of CDP-choline on the outcome of cardiac arrest in comparison with epinephrine.

METHODS

This was a randomized prospective animal study. Cardiac arrest was induced by asphyxia in 45 rats. After 7 minutes of asphyxia, resuscitation was attempted. The rats were allocated to different groups treated with 2 mL/kg saline, 100 μg/kg epinephrine, or 250 mg/kg CDP-choline. The hemodynamic parameters were monitored for 2 hours after resuscitation, and cardiac function was evaluated by echocardiography 2 hours after resuscitation. The hearts were harvested at the end of monitoring for histologic evaluation.

RESULTS

Epinephrine and CDP-choline improved the rate of return of spontaneous circulation and blood pressure during cardiopulmonary resuscitation; however, postresuscitation cardiac function in the CDP-choline and placebo groups was better than in the epinephrine group. Compared with the epinephrine group, less myocardial and mitochondrial injury was observed by electron microscopy in the CDP-choline and placebo groups; the level of superoxide dismutase and malondialdehyde indicated less peroxidative injury in the CDP-choline and placebo groups. Cytidine diphosphate choline and placebo also preserved connexin 43 when compared with epinephrine.

CONCLUSION

When administered during resuscitation, CDP-choline increased the rate of return of spontaneous circulation similarly to epinephrine. In addition, it did not increase the severity of myocardial injury and postresuscitation myocardial dysfunction, whereas epinephrine appeared to be harmful.

Wide variability in drug use in out-of-hospital cardiac arrest: a report from the resuscitation outcomes consortium

BACKGROUND

Despite the publication and dissemination of the Advanced Cardiac Life Support guidelines, variability in the use of drugs during resuscitation from out-of-hospital cardiac arrest may exist between different Emergency Medical Services throughout North America. The purpose of this study was to characterize the use of such drugs and evaluate their relationship to cardiac arrest outcomes.

METHODS AND RESULTS

The Resuscitation Outcomes Consortium Registry-Cardiac Arrest collects out-of-hospital cardiac arrest data from 264 Emergency Medical Services agencies in 11 geographical locations in the U.S. and Canada. Multivariable logistic regression was used to assess the association between drug use, characteristics of the cardiac arrest and a pulse at emergency department arrival and survival to discharge. A total of 16,221 out-of-hospital cardiac arrests were attended by 74 Emergency Medical Services agencies. There was a considerable variability in the administration of amiodarone and lidocaine for the treatment of shock resistant ventricular tachycardia/ventricular fibrillation. For non-shockable rhythms, atropine use ranged from 29 to 95% and sodium bicarbonate use ranged from 0.2 to 73% across agencies in the 89% of agencies that used the drug. Epinephrine use ranged from 57 to 98% within agencies. Neither lidocaine nor amiodarone was associated with a survival benefit while there was an inverse relationship between the administration of epinephrine, atropine and sodium bicarbonate and survival to hospital discharge.

CONCLUSIONS

There is considerable variability among Emergency Medical Services agencies in their use of pharmacological therapy for out-of-hospital cardiac arrests which may be resolved by performing large randomized trials examining effects on survival.

Variable effects of high-dose adrenaline relative to standard-dose adrenaline on resuscitation outcomes according to cardiac arrest duration

AIM OF THE STUDY

Adjustment of adrenaline (epinephrine) dosage according to cardiac arrest (CA) duration, rather than administering the same dose, may theoretically improve resuscitation outcomes. We evaluated variable effects of high-dose adrenaline (HDA) relative to standard-dose adrenaline (SDA) on resuscitation outcomes according to CA duration.

METHODS

Twenty-eight male domestic pigs were randomised to the following 4 groups according to the dosage of adrenaline (SDA 0.02 mg/kg vs. HDA 0.2mg/kg) and duration of CA before beginning cardiopulmonary resuscitation (CPR): 6 min SDA, 6 min HDA, 13 min SDA, or 13 min HDA. After the predetermined duration of untreated ventricular fibrillation, CPR was provided.

RESULTS

All animals in the 6 min SDA, 6 min HDA, and 13 min HDA groups were successfully resuscitated, while only 4 of 7 pigs in the 13 min SDA group were successfully resuscitated (p=0.043). HDA groups showed higher right atrial pressure, more frequent ventricular ectopic beats, higher blood glucose, higher troponin-I, and more severe metabolic acidosis than SDA groups. Animals of 13 min groups showed more severe metabolic acidosis and higher troponin-I than animals of 6 min groups. All successfully resuscitated animals, except two animals in the 13 min HDA group, survived for 7 days (p=0.121). Neurologic deficit score was not affected by the dose of adrenaline.

CONCLUSION

HDA showed benefit in achieving restoration of spontaneous circulation in 13 min CA, when compared with 6 min CA. However, this benefit did not translate into improved long-term survival or neurologic outcome.

Part 10: Pediatric basic and advanced life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

Note From the Writing Group: Throughout this article, the reader will notice combinations of superscripted letters and numbers (eg, “Family Presence During ResuscitationPeds-003”). These callouts are hyperlinked to evidence-based worksheets, which were used in the development of this article. An appendix of worksheets, applicable to this article, is located at the end of the text. The worksheets are available in PDF format and are open access.

Vascular access and drug therapy in pediatric resuscitation

Using the evidence brought together through the 2005 International Liaison Committee on Resuscitation evidence evaluation process and the subsequent 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care, the role for specific drug therapy in pediatric cardiac arrest is outlined. The drugs discussed include epinephrine, vasopressin, calcium, sodium bicarbonate, atropine, magnesium, and glucose. The literature addressing how best to deliver these drugs to the critically ill child is also presented, specifically looking at the use of intraosseous and endotracheal drug therapy.

Vasopressors for cardiopulmonary resuscitation. Does pharmacological evidence support clinical practice?

Adrenaline (epinephrine) has been used for cardiopulmonary resuscitation (CPR) since 1896. The rationale behind its use is thought to be its alpha-adrenoceptor-mediated peripheral vasoconstriction, causing residual blood flow to be diverted to coronary and cerebral circulations. This protects these tissues from ischaemic damage and increases the likelihood of restoration of spontaneous circulation. Clinical trials have not demonstrated any benefit of adrenaline over placebo as an agent for resuscitation. Adrenaline has deleterious effects in the setting of resuscitation, predictable from its promiscuous pharmacological profile. This article discusses the relevant pharmacology of adrenaline in the context of CPR. Experimental and clinical evidences for the use of adrenaline and alternative vasopressor agents in resuscitation are given, and the properties of an ideal vasopressor are discussed.

Is cardiopulmonary resuscitation warranted in children who suffer cardiac arrest post trauma?

The use of cardiopulmonary resuscitation (CPR) is accepted universally for patients with cardiovascular compromise. However, outcomes from CPR in subsets of trauma patients may not be as good as initially thought. This article reviews the literature on outcomes from traumatic arrest in both adults and children. Outcomes for adults and children are similar, although the types of injuries may differ. Patients with asystolic arrest at the scene have very poor survival, and those who do survive sustain severe neurological injury. Recognizing that most providers would feel uncomfortable at not attempting resuscitation, the length and degree of aggressiveness of CPR is addressed. Finally, we discuss possible reasons to resuscitate. Organ donation and the ethics of nontherapeutic ventilation and other strategies to increase the donor pool are discussed. We hope to stimulate discussion around a very difficult issue.

Cardiopulmonary resuscitation algorithms, defibrillation and optimized ventilation during resuscitation

PURPOSE OF REVIEW

In 2005, the American Heart Association released its Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. This article reviews the treatment algorithms for Advanced Cardiac Life Support, citing the evidence on which the Guidelines are based. Additional focus is placed on defibrillation and optimized ventilation.

RECENT FINDINGS

Major changes include a reorganization of the algorithms for cardiac arrest. Emphasis on effective cardiopulmonary resuscitation is placed as the key to improved survival. Single defibrillation shocks are recommended (compared with three 'stacked' shocks) with immediate provision of cardiopulmonary resuscitation and minimal interruptions in chest compressions. The recommended chest compression : ventilation rate for single rescuers has been changed to 30:2.

SUMMARY

Despite advances in resuscitation science, basic life support remains the key to improving survival outcomes. Ultimately, as new knowledge is gained, we believe resuscitation therapies will be more individualized, on the basis of pathophysiology and etiology of the initial cardiac arrest.

Impact of informed consent requirements on cardiac arrest research in the United States: exception from consent or from research?

INTRODUCTION

Research in patients with life-threatening illness such as cardiac arrest is challenging since they can not consent. The Food and Drug Administration addressed research under emergency conditions by publishing new criteria for exception from informed consent in 1996. We systematically reviewed randomized trials over a 10-year period to assess the impact of these regulations.

METHODS

Case-control study of published trials for cardiac arrest (cases) and atrial fibrillation (controls.) Studies were identified by using structured searches of MEDLINE and EMBASE from 1992 to 2002. Included were studies using random allocation in humans with cardiac arrest or atrial fibrillation prior to enrollment. Excluded were duplicate publications. Number of American trials, foreign trials and proportion of trials of American origin were compared by using regression analysis. Changes in cardiac arrest versus atrial fibrillation trials were calculated as risk differences.

RESULTS

Of 4982 identified cardiac arrest studies, 57 (1.1%) were randomized trials. The number of American cardiac arrest trials decreased by 15% (95% CI: 8, 22%) annually (P = 0.05). The proportion of cardiac arrest trials of American origin decreased by 16% (95% CI: 10, 22%) annually (P = 0.006). Of 5596 identified atrial fibrillation studies, 197 trials (3.5%) were randomized trials. The risk difference between cardiac arrest versus atrial fibrillation trials being of American origin decreased significantly (annual difference -5.8% (95% CI: -10, -0.1%), P = 0.03).

INTERPRETATION

Fewer American cardiac arrest trials were published during the last decade, when federal consent requirements changed. Regulatory requirements for clinical trials may inhibit improvements in care and threaten public health.

A comparison of high-dose and standard-dose epinephrine in children with cardiac arrest

BACKGROUND

When efforts to resuscitate a child after cardiac arrest are unsuccessful despite the administration of an initial dose of epinephrine, it is unclear whether the next dose of epinephrine (i.e., the rescue dose) should be the same (standard) dose or a higher dose.

METHODS

We performed a prospective, randomized, double-blind trial to compare high-dose epinephrine (0.1 mg per kilogram of body weight) with standard-dose epinephrine (0.01 mg per kilogram) as rescue therapy for in-hospital cardiac arrest in children after failure of an initial, standard dose of epinephrine. The trial included 68 children, and Utstein-style reporting guidelines were used. The primary outcome measure was survival 24 hours after the arrest.

RESULTS

The rate of survival at 24 hours was lower in the group assigned to a high dose of epinephrine as rescue therapy than in the group assigned to a standard dose: 1 of the 34 patients in the high-dose group survived for 24 hours, as compared with 7 of the 34 patients in the standard-dose group (unadjusted odds ratio for death with the high dose, 8.6; 97.5 percent confidence interval, 1.0 to 397.0; P=0.05). After adjustment by multiple logistic-regression analysis for differences in the groups at the time of arrest, the high-dose group tended to have a lower 24-hour survival rate (odds ratio for death, 7.9; 97.5 percent confidence interval, 0.9 to 72.5; P=0.08). The two treatment groups did not differ significantly in terms of the rate of return of spontaneous circulation (which occurred in 20 patients in the high-dose group and 21 of those in the standard-dose group; odds ratio, 1.1; 97.5 percent confidence interval, 0.4 to 3.0). None of the patients in the high-dose group, as compared with four of those in the standard-dose group, survived to hospital discharge. Among the 30 patients whose cardiac arrest was precipitated by asphyxia, none of the 12 who were assigned to high-dose epinephrine were alive at 24 hours, as compared with 7 of the 18 who were assigned to a standard dose (P=0.02).

CONCLUSIONS

We did not find any benefit of high-dose epinephrine rescue therapy for in-hospital cardiac arrest in children after failure of an initial standard dose of epinephrine. The data suggest that high-dose therapy may be worse than standard-dose therapy.

Study examining attitudes of staff, patients and relatives to witnessed resuscitation in adult intensive care units

BACKGROUND

Witnessed resuscitation is widely accepted in paediatric practice and is becoming more common in adult emergency departments, but information on this topic is sparse.

METHODS

We gave a questionnaire to 50 intensive care medical and nursing staff and 55 patients and next of kin before elective postoperative admission to the intensive care unit to examine staff opinion about witnessed resuscitation, patient and relatives' demand for witnessed resuscitation, and their perception of the benefits.

RESULTS

We found that 56% of doctors and 66% of nurses favoured giving relatives the option to stay. If relatives requested to be present, 70% of doctors and 82% of nurses would allow this if the relatives were escorted. The role of the escort was felt to explain, prevent interference, and to provide emotional support. We found that 29% of patients and 47% of relatives wanted to be together during resuscitation, the commonest reasons being to provide support and to see that everything was done. We found that 95% of patients and 91% of relatives felt their views should be formally sought before ICU admission.

CONCLUSIONS

Intensive care staff support witnessed resuscitation. Many intensive care personnel have experienced witnessed resuscitation and the majority felt that relatives gained benefit. Almost all agree that the views of both patient and relatives should be sought formally before admission to intensive care.

Pediatric cardiopulmonary-cerebral resuscitation: an overview and future directions

The evolving understanding of pathophysiologic events during and after pediatric cardiac arrest has not yet resulted in significantly improved outcome. Exciting breakthroughs in basic and applied science laboratories are, however, on the immediate horizon for study in specific subpopulations of cardiac arrest victims. Strategically focusing therapies to specific phases of cardiac arrest and resuscitation and evolving pathophysiologic events offers great promise that critical care interventions will lead the way to more successful cardiopulmonary and cerebral resuscitation in children.

Update on cardiac resuscitation for sudden death: International Guidelines 2000 on Resuscitation and Emergency Cardiac Care

Cardiopulmonary resuscitation developed over the past one half century largely from empiric science and consensus opinions and recommendations. Treatment algorithms and protocols were originally developed to summarize existing recommendations for systematic and regimented use by a heterogenous group of health care providers. Now, resuscitation science and health care teams are focusing on major issues and continuing questions as sudden death rates remain undaunted and the population at risk is rapidly increasing. For the first time, the international resuscitation community has developed an international consensus on Guidelines for Resuscitation and Emergency Cardiac Care. More than 400 basic scientists, clinical trial investigators, and educators defined common priority and scientific areas during the Evidence Evaluation International Meeting in 1999. The science of resuscitation and emergency cardiac care was reviewed for evidence-based support in randomized clinical trials. In 2000, this review was used as a foundation to structure international guidelines. The participants from seven resuscitation councils and foundations realized that regional differences in systems may exist, but the underlying science should be the same. Presented in this article are some of the major issues and controversies discussed in adult advanced cardiac life support, primarily focusing on the major problem of prehospital adult cardiac arrest.

The rotational technique with a partially inflated laryngeal mask airway improves the ease of insertion in children

BACKGROUND

This study compared the ease of insertion of the laryngeal mask airway (LMA) with a partially inflated cuff using the standard 'nonrotational' technique versus the rotational technique.

METHODS

One hundred and forty-five children undergoing anaesthesia using the LMA were randomly assigned to either method. The cuff was partially inflated in both groups. The ease of insertion was assessed by the time taken to complete the LMA insertion, the number of attempts before successful placement and the occurrence of complications.

RESULTS

The success rate of insertion at the first attempt was higher in the rotational technique group (99% versus 79%, P < 0.05). All patients in the rotational group had the mask inserted within two attempts. On the other hand, three patients had the mask inserted on the first attempt with the rotational technique after three unsuccessful attempts by an anaesthesiologist with the standard 'nonrotational' technique. Insertion technique made no difference on insertion time.

CONCLUSIONS

The rotational technique was associated with a higher success rate for insertion and a lower incidence of complications in children. Using the rotational technique with a partially inflated cuff could be the first-choice approach in paediatric patients.

Update in pediatric resuscitation

This article updates research concerning the resuscitation of a pediatric patient. The topics discussed include the state of pediatric life support, the current guidelines, the management of those guidelines, and coping with death.

High dose versus standard dose epinephrine in cardiac arrest - a meta-analysis

In the management of cardiac arrest there is ongoing controversy concerning the optimal dose of epinephrine. To obtain the best available evidence regarding the current optimal dose, we performed a meta-analysis. We searched the Medline database online and reviewed citations in relevant articles to identify studies that met preset inclusion criteria (prospective, randomized, double-blind). Five trials were identified. The pooled odds ratio for return of spontaneous circulation favours the experimental dose. The pooled odds ratio for hospital discharge failed to demonstrate a statistically significant beneficial effect of high and/or escalating doses of epinephrine in comparison with standard dose of epinephrine. The possibility that patients who have already sustained irreversible neurologic injury will be resuscitated carries potential adverse social and economic implications.

Good clinical research practice: what is it and is it possible in the intensive care unit?

With the growing quest for answers to vexing dilemmas in critically ill patients, more intensive care units are embarking on clinical research. This places increasing importance on Good Clinical Research Practice (GCRP), a set of guidelines drawn up by the Pharmaceutical Industry to assist investigators in conducting ethical, reliable scientific studies. GCRP is a combination of good basic management skills allied to ethical principles for scientific research. Based on the principles of the Declaration of Helsinki, it consists of three tenets: patient protection (ethics), credible data (science) and data control. This article describes GCRP specifically relating it to the intensive care situation, illustrating some of the concepts with practical examples. With a minimum of extra time and effort these basic principles can be integrated as routine into all research projects.

A randomized, blinded trial of high-dose epinephrine versus standard-dose epinephrine in a swine model of pediatric asphyxial cardiac arrest

OBJECTIVE

To determine whether high-dose epinephrine administration during cardiopulmonary resuscitation (CPR) in a swine pediatric asphyxial cardiac arrest model improves outcome (i.e., resuscitation rate, survival rate, and neurologic function) compared with standard-dose epinephrine.

DESIGN

A randomized, blinded study.

SETTING

A large animal cardiovascular laboratory at a university.

SUBJECTS

Thirty domestic piglets (3 to 4 months of age) were randomized to receive standard-dose epinephrine (0.02 mg/kg) or high-dose epinephrine (0.2 mg/kg) during CPR after 10 mins of cardiac standstill with loss of aortic pulsation after endotracheal tube clamping.

INTERVENTIONS

Two minutes of CPR were provided, followed by advanced pediatric life support. Successfully resuscitated animals were supported in an intensive care unit (ICU) setting for 2 hrs and then observed for 24 hrs.

MEASUREMENTS AND MAIN RESULTS

Electrocardiogram, thoracic aortic blood pressure, and right atrial blood pressure were monitored continuously until the intensive care period ended. Survival rate and neurologic outcome were determined. Return of spontaneous circulation was obtained in 13 of 15 high-dose epinephrine piglets vs. ten of 15 standard-dose epinephrine piglets (p < .20). Four of 13 high-dose piglets died in the ICU period after initial resuscitation vs. 0 of ten standard-dose piglets (p < or = .05). Nine high-dose piglets survived 2 hrs vs. ten standard-dose piglets. Three piglets in each group survived for 24 hrs, but all were severely neurologically impaired. Two minutes after resuscitation, piglets treated with high-dose epinephrine had higher heart rates (210 +/- 24 vs. 189 +/- 40 beats/min, p < .05) and higher aortic diastolic pressures (121 +/- 39 vs. 74 +/- 40 mm Hg, p < .01). Within 10 mins of return of spontaneous circulation, severe tachycardia (> 240 beats/min) was more frequently noted in the high-dose group than in the standard-dose group (p < .05). All four high-dose piglets that died in the ICU period experienced ventricular fibrillation within 10 mins of return of spontaneous circulation.

CONCLUSIONS

High-dose epinephrine did not improve 2-hr survival rate, 24-hr survival rate, or neurologic outcome. High-dose epinephrine resulted in severe tachycardia and hypertension immediately after resuscitation and in a higher mortality rate immediately after resuscitation.

Reporting approval by research ethics committees and subjects' consent in human resuscitation research

OBJECTIVE

To determine how frequently reports of research in human cardiopulmonary resuscitation mention approval by a research ethics committee and address subjects' consent.

METHODS

Retrospective review of published reports of interventional research in human cardiopulmonary resuscitation. Reports were retrieved from the MEDLINE database and selected according to pre-established criteria. Data were abstracted independently by the two authors with differences resolved by mutual agreement. Results were analyzed according to whether the research took place in the prehospital setting, the emergency department, or the hospital; whether it was conducted within or outside the United States; whether it received any funding from the US government; its randomization scheme; the year of publication; and whether the journal's instructions required mention of REC approval or subjects' consent.

RESULTS

Reports of 47 studies met our criteria for inclusion. Of these, 24 (51%) mentioned approval by a research ethics committee and 12 (26%) addressed subjects' consent. Significantly more studies reported ethics committee approval or addressed consent during more recent years. Authors were more likely to report consent, REC approval, or both when journal instructions required that REC approval be mentioned.

CONCLUSION

Reports of resuscitation research have not consistently mentioned approval from a research ethics committee or addressed subjects' consent for interventional studies using human subjects. However, they are doing so more frequently in recent years as journal requirements for reporting change. REC approval is now almost always being reported, but subjects' consent is often not addressed. Journal editors and reviewers should ensure that authors adhere to the journal's instructions about reporting ethical conduct of experiments.

Cardiac arrest research in humans--insights into failure

Cardiac arrest research in humans has failed to fulfil expectations generated by laboratory studies. This reflects a number of factors. It is difficult to perform clinical research in the setting of emergency cardiac resuscitation. Both the epidemiology and pathophysiology of sudden death present special problems to the clinical researcher. Laboratory studies and clinical trials have failed to faithfully mimic each other. Estimation of sample size and application of inclusion/exclusion criteria present special problems in methodology. Our focus on improving long term survival by changing one component of therapy may have been premature and obscured the utility of extant data. Many of these problems can be addressed through refinements in: laboratory models, our understanding of the underlying pathophysiology, estimation of sample size, the application of inclusion/exclusion criteria, the identification of the primary dependent variables and subgroups of interest, the overall quality of therapy. Clinical studies will not generate useful data until these issues, among others, have been addressed.