European Resuscitation Council Guidelines 2000 for Adult Advanced Life Support: A statement from the Advanced Life Support Working Group¹ and approved by the Executive Committee of the European Resuscitation Council

The International Liaison Committee on Resuscitation engages in a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation and first aid science. Draft Consensus on Science With Treatment Recommendations are posted online throughout the year, and this annual summary provides more concise versions of the final Consensus on Science With Treatment Recommendations from all task forces for the year. Topics addressed by systematic reviews this year include resuscitation of cardiac arrest from drowning, extracorporeal cardiopulmonary resuscitation for adults and children, calcium during cardiac arrest, double sequential defibrillation, neuroprognostication after cardiac arrest for adults and children, maintaining normal temperature after preterm birth, heart rate monitoring methods for diagnostics in neonates, detection of exhaled carbon dioxide in neonates, family presence during resuscitation of adults, and a stepwise approach to resuscitation skills training. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research. Additional topics are addressed with scoping reviews and evidence updates.

To examine the impact of time to amiodarone administration on survival from shock-refractory Ventricular Fibrillation/pulseless Ventricular Tachycardia (VF/pVT) following out-of-hospital cardiac arrest (OHCA).

A retrospective cohort study of adult (≥16 years) OHCA patients in shock-refractory VF/pVT (after 3 consecutive defibrillation attempts) of medical aetiology who arrested between January 2010 and December 2019. Time-dependent propensity score matching was used to sequentially match patients who received amiodarone at any given minute of resuscitation with patients eligible to receive amiodarone during the same minute. Log-binomial regression models were used to assess the association between time of amiodarone administration (by quartiles of time-to-matching) and survival outcomes.

A total of 2,026 patients were included, 1,393 (68.8%) of whom received amiodarone with a median (interquartile range) time to administration of 22.0 (18.0–27.0) minutes. Propensity score matching yielded 1,360 matched pairs. Amiodarone administration within 28 minutes of the emergency call was associated with a higher likelihood of return of spontaneous circulation (ROSC) (≤18minutes: RR = 1.03 (95%CI 1.02, 1.04); 19-22minutes: RR = 1.02 (95%CI 1.01, 1.03); 23-27minutes: RR = 1.01 (95%CI 1.00, 1.02)) and event survival (pulse on hospital arrival) (≤18 minutes: RR = 1.05 (95%CI 1.03, 1.07); 19–22 minutes: RR = 1.03 (95%CI 1.01, 1.05); 23–27 minutes: RR = 1.02 (95%CI 1.00, 1.03). Amiodarone administration within 23 minutes of the emergency call was associated with a higher likelihood of survival to hospital discharge (≤18minutes: RR = 1.17 (95%CI 1.09, 1.24; 19–22 minutes: RR = 1.10 (95%CI 1.04, 1.17).

Amiodarone administered within 23 minutes of the emergency call is associated with improved survival outcomes in shock-refractory VF/pVT, although prospective trials are required to confirm these findings.

Recent evidence showing the clinical effectiveness of drug therapy in cardiac arrest has led to renewed interest in the optimal route for drug administration in adult out-of-hospital cardiac arrest. Current resuscitation guidelines support use of the intravenous route for intra-arrest drug delivery, with the intraosseous route reserved for patients in whom intravenous access cannot be established.

We sought to evaluate current evidence on drug route for administration of cardiac arrest drugs, with a specific focus on the intravenous and intraosseous route. We identified relevant animal, manikin, and human studies through targeted searches of MEDLINE in June 2022.

Across pre-hospital systems, there is wide variation in use of the intraosseous route. Early administration of cardiac arrest drugs is associated with improved patient outcomes. Challenges in obtaining intravenous access mean that the intraosseous access may facilitate earlier drug administration. However, time from administration to the central circulation is unclear with pharmacokinetic data limited mainly to animal studies.

Observational studies comparing the effect of intravenous and intraosseous drug administration on patient outcomes are challenging to interpret because of resuscitation time bias and other confounders. To date, no randomised controlled trial has directly compared the effect on patient outcomes of intraosseous compared with intravenous drug administration in cardiac arrest.

The International Liaison Committee on Resuscitation has described the urgent need for randomised controlled trials comparing the intravenous and intraosseous route in adult out-of-hospital cardiac arrest. Ongoing clinical trials will directly address this knowledge gap.

There is a lack of new promising therapies to improve the dismal outcomes from cardiac arrest. The objectives of this study were: (1) To identify novel pharmacological therapies investigated in experimental animal studies and (2) to identify pharmacological therapies translated from experimental animal studies to clinical trials.

PubMed was searched to first identify relevant experimental cardiac arrest animal models published within the last 20 years. Based on this, a list of interventions was created and a second search was performed to identify clinical trials testing one of these interventions. Data extraction was performed using standardised data extraction forms.

We identified 415 animal studies testing 190 different pharmacological interventions. The most commonly tested interventions were classified as vasopressors, anaesthetics/gases, or interventions aimed at molecular targets. We found 43 clinical trials testing 26 different interventions identified in the animal studies. Of these, 13 trials reported positive findings and 30 trials reported neutral findings with regards to the primary endpoint. No study showed harm of the intervention. Some interventions tested in human clinical trials, had previously been tested in animal studies without a positive effect on outcomes. A large number of animal studies was performed after publication of a clinical trial.

Numerous different pharmacological interventions have been tested in experimental animal models. Despite this only a limited number of these interventions have advanced to clinical trials, however several of the clinical trials tested interventions that were first tested in experimental animal models.

To characterize what proportion of all randomized controlled trials (RCTs) among patients experiencing cardiac arrest find that an established practice is ineffective or harmful, that is, a medical reversal.

We reviewed a database of all published RCTs of cardiac arrest patient populations between 1995 and 2014. Articles were classified on the basis of whether they tested a new or existing therapy and whether results were positive or negative. A reversal was defined as a negative RCT of an established practice. Further review and categorization were performed to confirm that reversals were supported by subsequent systematic review, as well as to identify the type of medical practice studied in each reversal. This study was conducted from October 2017 to June 17, 2019.

We reviewed 92 original articles, 76 of which could be conclusively categorized. Of these, 18 (24%) articles examined a new medical practice, whereas 58 (76%) tested an established practice. A total of 18 (24%) studies had positive findings, whereas 58 (76%) reached a negative conclusion. Of the 58 articles testing existing standard of care, 44 (76%) reversed that practice, whereas 14 (24%) reaffirmed it.

Reversal of cardiopulmonary resuscitation practices is widespread. This investigation sheds new light on low-value practices and patterns of medical research and suggests that novel resuscitation practices have low pretest probability and should be empirically tested with rigorous trials before implementation.

Most guidelines recommend pausing chest compressions at 2 min intervals to analyze the cardiac rhythm. We conducted a systematic review and meta-analysis to define the optimal interval at which to pause chest compressions in adults for cardiac rhythm analysis in any setting.

We searched PubMed, Embase, and Cochrane databases through January 2, 2015, including human studies addressing any two different intervals of rhythm analysis. GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) methodology evaluated confidence in estimates of effect for evidence pertaining to functional outcome, survival, and return of spontaneous circulation.

Of 1,136 identified papers, nine were included (three RCTs and six observational studies). Quality of evidence for each outcome was very low or low (usually downgraded risk of bias and indirectness). RCTs comparing specific intervals (3 min vs. immediate rhythm analysis; 1 vs. 2 min; 3 vs. 1 min) demonstrated no difference between either arm. Meta-analyses of observational studies demonstrated benefit for a bundled ‘minimally interrupted chest compression’ protocol dictating 200-compression intervals compared with historical controls treated with 1- or 3 min intervals per the 2000 guidelines (OR 1.85, 95% CI 1.27,2.68 for ROSC; OR 2.84, 95% CI 2.12,3.79 for survival to discharge; OR 2.94, 95% CI 1.60,5.37 for good functional outcome).

There is a paucity of quality evidence to support pausing chest compressions at any singular interval to assess the cardiac rhythm in adults in cardiac arrest in any setting. Very low-quality evidence suggests improved clinical outcomes in patients receiving 200-compression intervals compared with 1- or 3 min intervals.