Association Between Chest Compression Pause Duration and Survival After Pediatric In-Hospital Cardiac Arrest

BACKGROUND

The association between chest compression (CC) pause duration and pediatric in-hospital cardiac arrest survival outcomes is unknown. The American Heart Association has recommended minimizing pauses in CC in children to <10 seconds, without supportive evidence. We hypothesized that longer maximum CC pause durations are associated with worse survival and neurological outcomes.

METHODS

In this cohort study of index pediatric in-hospital cardiac arrests reported in pediRES-Q (Quality of Pediatric Resuscitation in a Multicenter Collaborative) from July of 2015 through December of 2021, we analyzed the association in 5-second increments of the longest CC pause duration for each event with survival and favorable neurological outcome (Pediatric Cerebral Performance Category ≤3 or no change from baseline). Secondary exposures included having any pause >10 seconds or >20 seconds and number of pauses >10 seconds and >20 seconds per 2 minutes.

RESULTS

We identified 562 index in-hospital cardiac arrests (median [Q1, Q3] age 2.9 years [0.6, 10.0], 43% female, 13% shockable rhythm). Median length of the longest CC pause for each event was 29.8 seconds (11.5, 63.1). After adjustment for confounders, each 5-second increment in the longest CC pause duration was associated with a 3% lower relative risk of survival with favorable neurological outcome (adjusted risk ratio, 0.97 [95% CI, 0.95-0.99]; P=0.02). Longest CC pause duration was also associated with survival to hospital discharge (adjusted risk ratio, 0.98 [95% CI, 0.96-0.99]; P=0.01) and return of spontaneous circulation (adjusted risk ratio, 0.93 [95% CI, 0.91-0.94]; P<0.001). Secondary outcomes of any pause >10 seconds or >20 seconds and number of CC pauses >10 seconds and >20 seconds were each significantly associated with adjusted risk ratio of return of spontaneous circulation, but not survival or neurological outcomes.

CONCLUSIONS

Each 5-second increment in longest CC pause duration during pediatric in-hospital cardiac arrest was associated with lower chance of survival with favorable neurological outcome, survival to hospital discharge, and return of spontaneous circulation. Any CC pause >10 seconds or >20 seconds and number of pauses >10 seconds and >20 seconds were significantly associated with lower adjusted probability of return of spontaneous circulation, but not survival or neurological outcomes.

Early versus late advanced airway management for adult patients with out-of-hospital cardiac arrest: A time-dependent propensity score-matched analysis

OBJECTIVE

The objective was to investigate whether early advanced airway management during the entire resuscitation period is associated with favorable neurological outcomes and survival in patients with out-of-hospital cardiac arrest (OHCA).

METHODS

We performed a retrospective cohort study of patients with OHCA aged ≥18 years enrolled in OHCA registry in Japan who received advanced airway management during cardiac arrest between June 2014 and December 2020. To address resuscitation time bias, we performed risk set matching analyses in which patients who did and did not receive advanced airway management were matched at the same time point (min) using the time-dependent propensity score; further, we compared early (≤10 min) and late (>10 min) advanced airway management. The primary and secondary outcome measures were favorable neurological outcomes using Cerebral Performance Category scores and survival at 1 month after cardiac arrest.

RESULTS

Of the 41,101 eligible patients, 21,446 patients received early advanced airway management. Thus, risk set matching was performed with a total of 42,866 patients. In the main analysis, early advanced airway management was significantly associated with favorable neurological outcomes (risk ratio [RR] 0.997, 95% confidence interval [CI] 0.995-0.999) and survival (RR 0.990, 95% CI 0.986-0.994) at 1 month after cardiac arrest. In the sensitivity analysis with early advanced airway management defined as ≤5 min and ≤20 min, the results were comparable.

CONCLUSIONS

Although early advanced airway management was statistically significant for improved neurological outcomes and survival at 1 month after cardiac arrest, the RR was very close to 1, indicating that the timing of advanced airway management has minimal impact on clinical outcomes, and decisions should be made based on the individual needs of the patient.

Autoimmune blistering disorders and cardiovascular risks: A population-based cohort study

BACKGROUND

Autoimmune blistering disorders (ABDs) might elevate cardiovascular risk, but studies are lacking.

OBJECTIVE

The objective of this study was to examine if ABDs elevate the risk of atherosclerotic cardiovascular disease, heart failure, arrhythmia, venous thromboembolism, and cardiovascular death.

METHODS

A population-based cohort of Danish patients with ABD (≥18 years of age) diagnosed during 1996-2021 (n = 3322) was compared with an age- and sex-matched comparison cohort from the general population (n = 33,195).

RESULTS

Compared with the general population, patients with ABDs had higher 1-year risks of atherosclerotic cardiovascular disease (3.4% vs 1.6%), heart failure (1.9% vs 0.7%), arrhythmia (3.8% vs 1.3%), venous thromboembolism (1.9% vs 0.3%), and cardiovascular death (3.3% vs 0.9%). The elevated risk persisted after 10 years for all outcomes but arrhythmia. The hazard ratios associating ABDs with the outcomes during the entire follow-up were 1.24 (1.09-1.40) for atherosclerotic cardiovascular disease, 1.48 (1.24-1.77) for heart failure, 1.16 (1.02-1.32) for arrhythmia, 1.87 (1.50-2.34) for venous thromboembolism, and 2.01 (1.76-2.29) for cardiovascular death. The elevated cardiovascular risk was observed for both pemphigus and pemphigoid.

LIMITATIONS

Our findings might only generalize to patients with ABDs without prevalent cardiovascular diseases.

CONCLUSION

Patients with ABDs had an elevated cardiovascular risk compared with age- and sex-matched controls.

Immune cell expression patterns of CD39/CD73 ectonucleotidases in rodent models of cardiac arrest and resuscitation

Background

Cardiac arrest (CA) is a significant public health concern. There is the high imminent mortality and survival in those who are resuscitated is substantively compromised by the post-CA syndrome (PCAS), characterized by multiorgan ischemia-reperfusion injury (IRI). The inflammatory response in PCAS is complex and involves various immune cell types, including lymphocytes and myeloid cells that have been shown to exacerbate organ IRI, such as myocardial infarction. Purinergic signaling, as regulated by CD39 and CD73, has emerged as centrally important in the context of organ-specific IRI. Hence, comprehensive understanding of such purinergic responses may be likewise imperative for improving outcomes in PCAS.

Methods

We have investigated alterations of immune cell populations after CA by utilizing rodent models of PCAS. Blood and spleen were collected after CA and resuscitation and underwent flow cytometry analysis to evaluate shifts in CD3+CD4+ helper T cells, CD3+CD8a+ cytotoxic T cells, and CD4/CD8a ratios. We then examined the expression of CD39 and CD73 across diverse cell types, including myeloid cells, T lymphocytes, and B lymphocytes.

Results

In both rat and mouse models, there were significant increases in the frequency of CD3+CD4+ T lymphocytes in PCAS (rat, P < 0.01; mouse, P < 0.001), with consequently elevated CD4/CD8a ratios in whole blood (both, P < 0.001). Moreover, CD39 and CD73 expression on blood leukocytes were markedly increased (rat, P < 0.05; mouse, P < 0.01 at 24h). Further analysis in the experimental mouse model revealed that CD11b+ myeloid cells, with significant increase in their population (P < 0.01), had high level of CD39 (88.80 ± 2.05 %) and increased expression of CD73 (P < 0.05). CD19+ B lymphocytes showed slight increases of CD39 (P < 0.05 at 2h) and CD73 (P < 0.05 at 2h), while, CD3+ T lymphocytes had decreased levels of them. These findings suggested a distinct patterns of expression of CD39 and CD73 in these specific immune cell populations after CA.

Conclusions

These data have provided comprehensive insights into the immune response after CA, highlighting high-level expressions of CD39 and CD73 in myeloid cells.

External Validation of Deep Learning-Based Cardiac Arrest Risk Management System for Predicting In-Hospital Cardiac Arrest in Patients Admitted to General Wards Based on Rapid Response System Operating and Nonoperating Periods: A Single-Center Study

OBJECTIVES

The limitations of current early warning scores have prompted the development of deep learning-based systems, such as deep learning-based cardiac arrest risk management systems (DeepCARS). Unfortunately, in South Korea, only two institutions operate 24-hour Rapid Response System (RRS), whereas most hospitals have part-time or no RRS coverage at all. This study validated the predictive performance of DeepCARS during RRS operation and nonoperation periods and explored its potential beyond RRS operating hours.

DESIGN

Retrospective cohort study.

SETTING

In this 1-year retrospective study conducted at Yonsei University Health System Severance Hospital in South Korea, DeepCARS was compared with conventional early warning systems for predicting in-hospital cardiac arrest (IHCA). The study focused on adult patients admitted to the general ward, with the primary outcome being IHCA-prediction performance within 24 hours of the alarm.

PATIENTS

We analyzed the data records of adult patients admitted to a general ward from September 1, 2019, to August 31, 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Performance evaluation was conducted separately for the operational and nonoperational periods of the RRS, using the area under the receiver operating characteristic curve (AUROC) as the metric. DeepCARS demonstrated a superior AUROC as compared with the Modified Early Warning Score (MEWS) and the National Early Warning Score (NEWS), both during RRS operating and nonoperating hours. Although the MEWS and NEWS exhibited varying performance across the two periods, DeepCARS showed consistent performance.

CONCLUSIONS

The accuracy and efficiency for predicting IHCA of DeepCARS were superior to that of conventional methods, regardless of whether the RRS was in operation. These findings emphasize that DeepCARS is an effective screening tool suitable for hospitals with full-time RRS, part-time RRS, and even those without any RRS.

May-Thurner Syndrome: The Worst-Case Scenario

May-Thurner syndrome (MTS) is caused by compression of the left common iliac vein by the right common iliac artery against the spinal column. It can range from asymptomatic or present with subtle and unspecific signs and symptoms and rarely exhibit severe complications such as pulmonary embolism (PE). The diagnosis is confirmed by typical imaging findings. Treatment may include conservative measures, anticoagulation, endovascular or even surgical options. We report the case of a 20-year-old female who presented with cardiac arrest caused by an acute massive PE. Further study showed partial thrombosis of the internal iliac veins resulting from MTS. She continued anticoagulation therapy with low-molecular-weight heparin and then switched to edoxaban with a good clinical outcome. She was also referred to Vascular Surgery to discuss the possibility of iliac vein stenting. Abdominopelvic vascular compression syndromes include a large spectrum of conditions, and they are rarely considered as an etiology for venous thromboembolism. The clinical presentation of PE varies with several triggering factors and atypical presentation is more common in nonmalignant causes. The combination of noninvasive and invasive imaging modalities might be beneficial to establish a definitive diagnosis. Nevertheless, invasive procedures are often restricted to doubtful cases or to guide endovascular procedures which is the current treatment of choice. There is little evidence using nonvitamin K oral anticoagulants, but there are some case reports detailing their successful use. This case aims to point out the need for a profound understanding of different causes of deep vein and pulmonary thromboembolism; common entities in our practice but with a variety of clinical presentations and potentially caused by rare underlying conditions. MTS can be the origin of serious and deadly complications, hence the importance of early recognition and treatment.

Compression-Only or Standard Cardiopulmonary Resuscitation for Trained Laypersons in Out-of-Hospital Cardiac Arrest: A Nationwide Randomized Trial in Sweden

BACKGROUND

The ongoing TANGO2 (Telephone Assisted CPR. AN evaluation of efficacy amonGst cOmpression only and standard CPR) trial is designed to evaluate whether compression-only cardiopulmonary resuscitation (CPR) by trained laypersons is noninferior to standard CPR in adult out-of-hospital cardiac arrest. This pilot study assesses feasibility, safety, and intermediate clinical outcomes as part of the larger TANGO2 survival trial.

METHODS

Emergency medical dispatch calls of suspected out-of-hospital cardiac arrest were screened for inclusion at 18 dispatch centers in Sweden between January 1, 2017, and March 12, 2020. Inclusion criteria were witnessed event, bystander on the scene with previous CPR training, age above 18 years of age, and no signs of trauma, pregnancy, or intoxication. Cases were randomized 1:1 at the dispatch center to either instructions to perform compression-only CPR (intervention) or instructions to perform standard CPR (control). Feasibility included evaluation of inclusion, randomization, and adherence to protocol. Safety measures were time to emergency medical service dispatch CPR instructions, and to start of CPR, intermediate clinical outcome was defined as 1-day survival.

RESULTS

Of 11 838 calls of suspected out-of-hospital cardiac arrest screened for inclusion, 2168 were randomized and 1250 (57.7%) were out-of-hospital cardiac arrests treated by the emergency medical service. Of these, 640 were assigned to intervention and 610 to control. Crossover from intervention to control occurred in 16.3% and from control to intervention in 18.5%. The median time from emergency call to ambulance dispatch was 1 minute and 36 s (interquartile range, 1.1-2.2) in the intervention group and 1 minute and 30 s (interquartile range, 1.1-2.2) in the control group. Survival to 1 day was 28.6% versus 28.4% (P=0.984) for intervention and control, respectively.

CONCLUSIONS

In this national randomized pilot trial, compression-only CPR versus standard CPR by trained laypersons was feasible. No differences in safety measures or short-term survival were found between the 2 strategies. Efforts to reduce crossover are important and may strengthen the ongoing main trial that will assess differences in long-term survival.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02401633.

The American Heart Association Emergency Cardiovascular Care 2030 Impact Goals and Call to Action to Improve Cardiac Arrest Outcomes: A Scientific Statement From the American Heart Association

Every 10 years, the American Heart Association (AHA) Emergency Cardiovascular Care Committee establishes goals to improve survival from cardiac arrest. These goals align with broader AHA Impact Goals and support the AHA's advocacy efforts and strategic investments in research, education, clinical care, and quality improvement programs. This scientific statement focuses on 2030 AHA emergency cardiovascular care priorities, with a specific focus on bystander cardiopulmonary resuscitation, early defibrillation, and neurologically intact survival. This scientific statement also includes aspirational goals, such as establishing cardiac arrest as a reportable disease and mandating reporting of standardized outcomes from different sources; advancing recognition of and knowledge about cardiac arrest; improving dispatch system response, availability, and access to resuscitation training in multiple settings and at multiple time points; improving availability, access, and affordability of defibrillators; providing a focus on early defibrillation, in-hospital programs, and establishing champions for debriefing and review of cardiac arrest events; and expanding measures to track outcomes beyond survival. The ability to track and report data from these broader aspirational targets will potentially require expansion of existing data sets, development of new data sets, and enhanced integration of technology to collect process and outcome data, as well as partnerships of the AHA with national, state, and local organizations. The COVID-19 (coronavirus disease 2019) pandemic, disparities in COVID-19 outcomes for historically excluded racial and ethnic groups, and the longstanding disparities in cardiac arrest treatment and outcomes for Black and Hispanic or Latino populations also contributed to an explicit focus and target on equity for the AHA Emergency Cardiovascular Care 2030 Impact Goals.

Associations Between End-Tidal Carbon Dioxide During Pediatric Cardiopulmonary Resuscitation, Cardiopulmonary Resuscitation Quality, and Survival

BACKGROUND

Supported by laboratory and clinical investigations of adult cardiopulmonary arrest, resuscitation guidelines recommend monitoring end-tidal carbon dioxide (ETCO2) as an indicator of cardiopulmonary resuscitation (CPR) quality, but they note that "specific values to guide therapy have not been established in children."

METHODS

This prospective observational cohort study was a National Heart, Lung, and Blood Institute-funded ancillary study of children in the ICU-RESUS trial (Intensive Care Unit-Resuscitation Project; NCT02837497). Hospitalized children (≤18 years of age and ≥37 weeks postgestational age) who received chest compressions of any duration for cardiopulmonary arrest, had an endotracheal or tracheostomy tube at the start of CPR, and evaluable intra-arrest ETCO2 data were included. The primary exposure was event-level average ETCO2 during the first 10 minutes of CPR (dichotomized as ≥20 mm Hg versus <20 mm Hg on the basis of adult literature). The primary outcome was survival to hospital discharge. Secondary outcomes were sustained return of spontaneous circulation, survival to discharge with favorable neurological outcome, and new morbidity among survivors. Poisson regression measured associations between ETCO2 and outcomes as well as the association between ETCO2 and other CPR characteristics: (1) invasively measured systolic and diastolic blood pressures, and (2) CPR quality and chest compression mechanics metrics (ie, time to CPR start; chest compression rate, depth, and fraction; ventilation rate).

RESULTS

Among 234 included patients, 133 (57%) had an event-level average ETCO2 ≥20 mm Hg. After controlling for a priori covariates, average ETCO2 ≥20 mm Hg was associated with a higher incidence of survival to hospital discharge (86/133 [65%] versus 48/101 [48%]; adjusted relative risk, 1.33 [95% CI, 1.04-1.69]; P=0.023) and return of spontaneous circulation (95/133 [71%] versus 59/101 [58%]; adjusted relative risk, 1.22 [95% CI, 1.00-1.49]; P=0.046) compared with lower values. ETCO2 ≥20 mm Hg was not associated with survival with favorable neurological outcome or new morbidity among survivors. Average 2 ≥20 mm Hg was associated with higher systolic and diastolic blood pressures during CPR, lower CPR ventilation rates, and briefer pre-CPR arrest durations compared with lower values. Chest compression rate, depth, and fraction did not differ between ETCO2 groups.

CONCLUSIONS

In this multicenter study of children with in-hospital cardiopulmonary arrest, ETCO2 ≥20 mm Hg was associated with better outcomes and higher intra-arrest blood pressures, but not with chest compression quality metrics.

Cardiac Catheterization Laboratory Management of the Comatose Adult Patient With an Out-of-Hospital Cardiac Arrest: A Scientific Statement From the American Heart Association

Out-of-hospital cardiac arrest is a leading cause of death, accounting for ≈50% of all cardiovascular deaths. The prognosis of such individuals is poor, with <10% surviving to hospital discharge. Survival with a favorable neurologic outcome is highest among individuals who present with a witnessed shockable rhythm, received bystander cardiopulmonary resuscitation, achieve return of spontaneous circulation within 15 minutes of arrest, and have evidence of ST-segment elevation on initial ECG after return of spontaneous circulation. The cardiac catheterization laboratory plays an important role in the coordinated Chain of Survival for patients with out-of-hospital cardiac arrest. The catheterization laboratory can be used to provide diagnostic, therapeutic, and resuscitative support after sudden cardiac arrest from many different cardiac causes, but it has a unique importance in the treatment of cardiac arrest resulting from underlying coronary artery disease. Over the past few years, numerous trials have clarified the role of the cardiac catheterization laboratory in the management of resuscitated patients or those with ongoing cardiac arrest. This scientific statement provides an update on the contemporary approach to managing resuscitated patients or those with ongoing cardiac arrest.

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.

Critical Care Management of Patients After Cardiac Arrest: A Scientific Statement From the American Heart Association and Neurocritical Care Society

The critical care management of patients after cardiac arrest is burdened by a lack of high-quality clinical studies and the resultant lack of high-certainty evidence. This results in limited practice guideline recommendations, which may lead to uncertainty and variability in management. Critical care management is crucial in patients after cardiac arrest and affects outcome. Although guidelines address some relevant topics (including temperature control and neurological prognostication of comatose survivors, 2 topics for which there are more robust clinical studies), many important subject areas have limited or nonexistent clinical studies, leading to the absence of guidelines or low-certainty evidence. The American Heart Association Emergency Cardiovascular Care Committee and the Neurocritical Care Society collaborated to address this gap by organizing an expert consensus panel and conference. Twenty-four experienced practitioners (including physicians, nurses, pharmacists, and a respiratory therapist) from multiple medical specialties, levels, institutions, and countries made up the panel. Topics were identified and prioritized by the panel and arranged by organ system to facilitate discussion, debate, and consensus building. Statements related to postarrest management were generated, and 80% agreement was required to approve a statement. Voting was anonymous and web based. Topics addressed include neurological, cardiac, pulmonary, hematological, infectious, gastrointestinal, endocrine, and general critical care management. Areas of uncertainty, areas for which no consensus was reached, and future research directions are also included. Until high-quality studies that inform practice guidelines in these areas are available, the expert panel consensus statements that are provided can advise clinicians on the critical care management of patients after cardiac arrest.

OHCA in Bosnia and Herzegovina: Before and During the COVID-19 Pandemic

Background

Out-of-hospital cardiac arrest (OHCA) refers to the cessation of mechanical cardiac activity outside healthcare facilities which requires prompt intervention and intensive resuscitative efforts. The COVID-19 pandemic has caused significant disruptions to OHCA systems-of-care, adversely affecting every component of the chain of survival.

Objective

The objective of this study was to examine the potential impacts of the COVID-19 pandemic on OHCA events, to draw comparisons between the period before and during the COVID-19 pandemic.

Methods

This cross-sectional study encompassed data pertaining to all OHCA incidents attended to by the Emergency Medical Service of Canton Sarajevo, covering the period from January 2017 to December 2022, before and during the COVID-19 pandemic.

Results

During observed period, a total of 1418 [796 (56.1%) before and 622 (43.9%) during COVID-19 pandemic] OHCA events have occurred in Canton Sarajevo of which 297 (20.9 %) [180 (12.7%) before and 117 (8.2%) during COVID-19 pandemic] obtained ROSC. After a 30-day period following the ROSC) it was observed that the predominant outcome, accounting for 181 (12.7%) [106 (7.4%) before and 75 (5.2%) during COVID-19 pandemic] of cases, was a complete recovery. An examination before and during COVID-19 pandemic revealed a decline in OHCA during the year 2021 and 2022 when COVID-19 pandemic was at its highest in the country Being younger, quicker EMT response time and individuals with the initial rhythm of VF or VT were significantly associated with obtaining ROSC (p<0.05). Only 48 (3.3%) of 1418 OHCA events were assisted by bystanders There was no report of AED usage.

Conclusion

In conclusion, our investigation highlights the impact of the COVID-19 pandemic on OHCA events in Canton Sarajevo, revealing a decrease in OHCA incidence and a reduction in cases achieving ROSC. Notably, EMT response time was shorter during the pandemic.

Bag-Valve-Mask Ventilation and Survival From Out-of-Hospital Cardiac Arrest: A Multicenter Study

BACKGROUND

Few studies have measured ventilation during early cardiopulmonary resuscitation (CPR) before advanced airway placement. Resuscitation guidelines recommend pauses after every 30 chest compressions to deliver ventilations. The effectiveness of bag-valve-mask ventilation delivered during the pause in chest compressions is unknown. We sought to determine: (1) the incidence of lung inflation with bag-valve-mask ventilation during 30:2 CPR; and (2) the association of ventilation with outcomes after out-of-hospital cardiac arrest.

METHODS

We studied patients with out-of-hospital cardiac arrest from 6 sites of the Resuscitation Outcomes Consortium CCC study (Trial of Continuous Compressions versus Standard CPR in Patients with Out-of-Hospital Cardiac Arrest). We analyzed patients assigned to the 30:2 CPR arm with ≥2 minutes of thoracic bioimpedance signal recorded with a cardiac defibrillator/monitor. Detectable ventilation waveforms were defined as having a bioimpedance amplitude ≥0.5 Ω (corresponding to ≥250 mL VT) and a duration ≥1 s. We defined a chest compression pause as a 3- to 15-s break in chest compressions. We compared the incidence of ventilation and outcomes in 2 groups: patients with ventilation waveforms in <50% of pauses (group 1) versus those with waveforms in ≥50% of pauses (group 2).

RESULTS

Among 1976 patients, the mean age was 65 years; 66% were male. From the start of chest compressions until advanced airway placement, mean±SD duration of 30:2 CPR was 9.8±4.9 minutes. During this period, we identified 26 861 pauses in chest compressions; 60% of patients had ventilation waveforms in <50% of pauses (group 1, n=1177), and 40% had waveforms in ≥50% of pauses (group 2, n=799). Group 1 had a median of 12 pauses and 2 ventilations per patient versus group 2, which had 12 pauses and 12 ventilations per patient. Group 2 had higher rates of prehospital return of spontaneous circulation (40.7% versus 25.2%; P<0.0001), survival to hospital discharge (13.5% versus 4.1%; P<0.0001), and survival with favorable neurological outcome (10.6% versus 2.4%; P<0.0001). These associations persisted after adjustment for confounders.

CONCLUSIONS

In this study, lung inflation occurred infrequently with bag-valve-mask ventilation during 30:2 CPR. Lung inflation in ≥50% of pauses was associated with improved return of spontaneous circulation, survival, and survival with favorable neurological outcome.

The International Cardiac Arrest Research Consortium Electroencephalography Database

OBJECTIVES

To develop the International Cardiac Arrest Research (I-CARE), a harmonized multicenter clinical and electroencephalography database for acute hypoxic-ischemic brain injury research involving patients with cardiac arrest.

DESIGN

Multicenter cohort, partly prospective and partly retrospective.

SETTING

Seven academic or teaching hospitals from the United States and Europe.

PATIENTS

Individuals 16 years old or older who were comatose after return of spontaneous circulation following a cardiac arrest who had continuous electroencephalography monitoring were included.

INTERVENTIONS

Not applicable.

MEASUREMENTS AND MAIN RESULTS

Clinical and electroencephalography data were harmonized and stored in a common Waveform Database-compatible format. Automated spike frequency, background continuity, and artifact detection on electroencephalography were calculated with 10-second resolution and summarized hourly. Neurologic outcome was determined at 3-6 months using the best Cerebral Performance Category (CPC) scale. This database includes clinical data and 56,676 hours (3.9 terabytes) of continuous electroencephalography data for 1,020 patients. Most patients died ( n = 603, 59%), 48 (5%) had severe neurologic disability (CPC 3 or 4), and 369 (36%) had good functional recovery (CPC 1-2). There is significant variability in mean electroencephalography recording duration depending on the neurologic outcome (range, 53-102 hr for CPC 1 and CPC 4, respectively). Epileptiform activity averaging 1 Hz or more in frequency for at least 1 hour was seen in 258 patients (25%) (19% for CPC 1-2 and 29% for CPC 3-5). Burst suppression was observed for at least 1 hour in 207 (56%) and 635 (97%) patients with CPC 1-2 and CPC 3-5, respectively.

CONCLUSIONS

The I-CARE consortium electroencephalography database provides a comprehensive real-world clinical and electroencephalography dataset for neurophysiology research of comatose patients after cardiac arrest. This dataset covers the spectrum of abnormal electroencephalography patterns after cardiac arrest, including epileptiform patterns and those in the ictal-interictal continuum.

Abdominal compressions during cardiopulmonary resuscitation: a scoping review

OBJECTIVES

to map the scientific evidence on the use of abdominal compressions during cardiopulmonary resuscitation in patients with cardiac arrest.

METHODS

this is a scoping review based on the question: "What is the evidence regarding the use of abdominal compressions during cardiopulmonary resuscitation in patients with cardiac arrest?". Publications up to August 2022 were collected from eight databases. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews was used.

RESULTS

seventeen publications were included. The identified general population consisted of adults and elderly individuals. The primary outcome revealed significant rates of return of spontaneous circulation. Secondary outcomes indicated a significant improvement in heart rate, blood pressure, oxygen saturation, and other outcomes.

CONCLUSIONS

abdominal compressions have been shown to be beneficial. However, further clinical studies are needed to identify the best execution method and its impacts.

Methodological analysis of a community-based training initiative using the EPIS framework: an ongoing initiative to empower 10 million bystanders in CPR and bleeding control

Background

Out-of-hospital cardiac arrest (OHCA) and life-threatening bleeding from trauma are leading causes of preventable mortality globally. Early intervention from bystanders can play a pivotal role in increasing the survival rate of victims. While great efforts for bystander training have yielded positive results in high-income countries, the same has not been replicated in low and middle-income countries (LMICs) due to resources constraints. This article describes a replicable implementation model of a nationwide program, aimed at empowering 10 million bystanders with basic knowledge and skills of hands-only cardiopulmonary resuscitation (CPR) and bleeding control in a resource-limited setting.

Methods

Using the EPIS (Exploration, Preparation, Implementation and Sustainment) framework, we describe the application of a national bystander training program, named 'Pakistan Life Savers Programme (PLSP)', in an LMIC. We discuss the opportunities and challenges faced during each phase of the program's implementation and identify feasible and sustainable actions to make them reproducible in similar low-resource settings.

Results

A high mortality rate owing to OHCA and traumatic life-threatening bleeding was identified as a national issue in Pakistan. After intensive discussions during the exploration phase, PLSP was chosen as a potential solution. The preparation phase oversaw the logistical administration of the program and highlighted avenues using minimal resources to attain maximum outreach. National implementation of bystander training started as a pilot in suburban schools and expanded to other institutions, with 127 833 bystanders trained to date. Sustainability of the program was targeted through its addition in a single national curriculum taught in schools and the development of a cohesive collaborative network with entities sharing similar goals.

Conclusion

This article provides a methodological framework of implementing a national intervention based on bystander response. Such programs can increase bystander willingness and confidence in performing CPR and bleeding control, decreasing preventable deaths in countries having a high mortality burden.

Level of evidence

Level VI.

Hospital-administered ECPR for out-of-hospital cardiac arrest: an observational cohort study

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is a treatment method for refractory out-of-hospital cardiac arrest (OHCA) requiring a complex chain of care.

METHODS

All cases of OHCA between 1 January 2016 and 31 December 2021 in the Helsinki University Hospital catchment area in which the ECPR protocol was activated were included in the study. The protocol involved patient transport from the emergency site with ongoing mechanical cardiopulmonary resuscitation (CPR) directly to the cardiac catheterisation laboratory where the implementation of extracorporeal membrane oxygenation (ECMO) was considered. Cases of hypothermic cardiac arrest were excluded. The main outcomes were the number of ECPR protocol activations, duration of prehospital and in-hospital time intervals, and whether the ECPR candidates were treated using ECMO or not.

RESULTS

The prehospital ECPR protocol was activated in 73 cases of normothermic OHCA. The mean patient age (SD) was 54 (±11) years and 67 (91.8%) of them were male. The arrest was witnessed in 67 (91.8%) and initial rhythm was shockable in 61 (83.6%) cases. The median ambulance response time (IQR) was 9 (7-11) min. All patients received mechanical CPR, epinephrine and/or amiodarone. Seventy (95.9%) patients were endotracheally intubated. The median (IQR) highest prehospital end-tidal CO2 was 5.5 (4.0-6.9) kPa.A total of 37 (50.7%) patients were treated with venoarterial ECMO within a median (IQR) of 84 (71-105) min after the arrest. Thirteen (35.1%) of them survived to discharge and 11 (29.7%) with a cerebral performance category (CPC) 1-2. In those ECPR candidates who did not receive ECMO, 8 (22.2%) received permanent return of spontaneuous circulation during transport or immediately after hospital arrival and 6 (16.7%) survived to discharge with a CPC 1-2.

CONCLUSIONS

Half of the ECPR protocol activations did not lead to ECMO treatment. However, every fourth ECPR candidate and every third patient who received ECMO-facilitated resuscitation at the hospital survived with a good neurological outcome.

2023 American Heart Association Focused Update on the Management of Patients With Cardiac Arrest or Life-Threatening Toxicity Due to Poisoning: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

In this focused update, the American Heart Association provides updated guidance for resuscitation of patients with cardiac arrest, respiratory arrest, and refractory shock due to poisoning. Based on structured evidence reviews, guidelines are provided for the treatment of critical poisoning from benzodiazepines, β-adrenergic receptor antagonists (also known as β-blockers), L-type calcium channel antagonists (commonly called calcium channel blockers), cocaine, cyanide, digoxin and related cardiac glycosides, local anesthetics, methemoglobinemia, opioids, organophosphates and carbamates, sodium channel antagonists (also called sodium channel blockers), and sympathomimetics. Recommendations are also provided for the use of venoarterial extracorporeal membrane oxygenation. These guidelines discuss the role of atropine, benzodiazepines, calcium, digoxin-specific immune antibody fragments, electrical pacing, flumazenil, glucagon, hemodialysis, hydroxocobalamin, hyperbaric oxygen, insulin, intravenous lipid emulsion, lidocaine, methylene blue, naloxone, pralidoxime, sodium bicarbonate, sodium nitrite, sodium thiosulfate, vasodilators, and vasopressors for the management of specific critical poisonings.

A model study for the classification of high-risk groups for cardiac arrest in general ward patients using simulation techniques

Currently, many hospitals use vital signs-based criteria such as modified early warning score (MEWS) and national early warning score (NEWS) to classify high-risk patients for cardiac arrest, but there are limitations in selecting high-risk patients with a possibility of cardiac arrest. The purpose of this study is to develop a cardiac arrest classification model to identify patients at high risk of cardiac arrest based on the patient family and past history, and blood test results after hospitalization, rather than vital signs. This study used electronic medical record (EMR) data from A university hospital, and patients in the high-risk group for cardiac arrest were defined as those who underwent cardio-pulmonary resuscitation (CPR) after cardiac arrest. Considering the use of the rapid response team of A university hospital, patients hospitalized in intensive care units (ICU), emergency medicine departments, psychiatric departments, pediatric departments, cardiology departments, and palliative care wards were excluded. This study included 325,534 patients, of which 3291 low-risk and 382 high-risk patients were selected for study. Data were split into training and validation data sets and univariate analysis was performed for 13 candidate risk factors. Then, multivariate analysis was performed using a bivariate logistic regression model, and an optimal model was selected using simulation analysis. In the training data set, it was calculated as sensitivity 75.25%, precision 21.59%, specificity 66.89%, accuracy 67.79%, F1 score 33.56, area under curve (AUC) 71.1 (95% confidence interval [CI] = 68.9-73.1 P value=<.001). In the validation data set, sensitivity 73.37%, precision 25.81%, specificity 75.03%, accuracy 74.86%, F1 score 38.19, AUC 74.2 (95% CI = 72.1-76.2, P value=<.001) were calculated. A model for classifying the high-risk group of cardiac arrest should be developed from various perspectives. In the future, in order to classify patients with high risk of cardiac arrest, a prospective study on the combined use of the model developed by this study and NEWS or MEWS should be conducted.

Organ Donation After Out-of-Hospital Cardiac Arrest: A Scientific Statement From the International Liaison Committee on Resuscitation

AIM OF THE REVIEW

Improving rates of organ donation among patients with out-of-hospital cardiac arrest who do not survive is an opportunity to save countless lives. The objectives of this scientific statement were to do the following: define the opportunity for organ donation among patients with out-of-hospital cardiac arrest; identify challenges and opportunities associated with organ donation by patients with cardiac arrest; identify strategies, including a generic protocol for organ donation after cardiac arrest, to increase the rate and consistency of organ donation from this population; and provide rationale for including organ donation as a key clinical outcome for all future cardiac arrest clinical trials and registries.

METHODS

The scope of this International Liaison Committee on Resuscitation scientific statement was approved by the International Liaison Committee on Resuscitation board and the American Heart Association, posted on ILCOR.org for public comment, and then assigned by section to primary and secondary authors. A unique literature search was completed and updated for each section.

RESULTS

There are a number of defining pathways for patients with out-of-hospital cardiac arrest to become organ donors; however, modifications in the Maastricht classification system need to be made to correctly identify these donors and to report outcomes with consistency. Suggested modifications to the minimum data set for reporting cardiac arrests will increase reporting of organ donation as an important resuscitation outcome. There are a number of challenges with implementing uncontrolled donation after cardiac death protocols, and the greatest impediment is the lack of legislation in most countries to mandate organ donation as the default option. Extracorporeal cardiopulmonary resuscitation has the potential to increase organ donation rates, but more research is needed to derive neuroprognostication rules to guide clinical decision-making about when to stop extracorporeal cardiopulmonary resuscitation and to evaluate cost-effectiveness.

CONCLUSIONS

All health systems should develop, implement, and evaluate protocols designed to optimize organ donation opportunities for patients who have an out-of-hospital cardiac arrest and failed attempts at resuscitation.

Cardiac Rhythm Changes During Transfer from the Emergency Medical Service to the Emergency Department: A Retrospective Tertiary Single-Center Analysis on Prevalence and Outcomes

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide. Cardiac rhythms of OHCA patients can change during transportation and transfer from emergency medical services (EMS) to the emergency department (ED).

OBJECTIVE

Our objective was to study the prevalence of cardiac rhythm changes during transfer from the EMS to the ED in OHCA patients and the possible association with clinical outcomes.

METHODS

We retrospectively studied adult OHCA patients admitted to the ED between January 2017 and December 2019. The primary outcome was the incidence of cardiac rhythm changes during transfer from EMS to the ED. Secondary outcomes were: ED survival, intensive care unit survival, hospital survival, and maximum Glasgow Coma Scale score during admission.

RESULTS

We included 625 patients, of whom there were 49 (7.8%) in the rhythm change group and 576 in the no rhythm change group. ED survival was significantly lower in the rhythm change group (26.5%) vs. the no rhythm change group (78.5%, p < 0.01).

CONCLUSION

Cardiac rhythm changes can occur in OHCA patients during transfer from EMS to the ED. Our results showed some evidence that these changes are associated with a lower ED survival.

Higher mean cerebral oxygen saturation shortly after extracorporeal cardiopulmonary resuscitation in patients who regain consciousness

INTRODUCTION

In cardiac arrest, cerebral ischemia and reperfusion injury mainly determine the neurological outcome. The aim of this study was to investigate the relation between the course of cerebral oxygenation and regain of consciousness in patients treated with extracorporeal cardiopulmonary resuscitation (ECPR). We hypothesized that rapid cerebral oxygenation increase causes unfavorable outcomes.

METHODS

This prospective observational study was conducted in three European hospitals. We included adult ECPR patients between October 2018 and March 2020, in whom cerebral regional oxygen saturation (rSO2 ) measurements were started minutes before ECPR initiation until 3 h after. The primary outcome was regain of consciousness, defined as following commands, analyzed using binary logistic regression.

RESULTS

The sample consisted of 26 ECPR patients (23% women, Agemean 46 years). We found no significant differences in rSO2 values at baseline (49.1% versus 49.3% for regain versus no regain of consciousness). Mean cerebral rSO2 values in the first 30 min after ECPR initiation were higher in patients who regained consciousness (38%) than in patients who did not regain consciousness (62%, odds ratio 1.23, 95% confidence interval 1.01-1.50).

CONCLUSION

Higher mean cerebral rSO2 values in the first 30 min after initiation of ECPR were found in patients who regained consciousness.

Fibrinolysis in Cardiac Arrest Patients Treated with Hypothermia

Hypothermia affects coagulation, but the effect of hypothermia on fibrinolysis is not clarified. Imbalance in the fibrinolytic system may lead to increased risk of bleeding or thrombosis. Our aim was to investigate if resuscitated cardiac arrest patients treated with hypothermia had an unbalanced fibrinolysis. A prospective cohort study, including 82 patients were treated with hypothermia at 33°C ± 1°C after out-of-hospital cardiac arrest. Blood samples were collected at 24 hours (hypothermia) and at 72 hours (normothermia). Samples were analyzed for fibrin D-dimer, tissue plasminogen activator (tPA), plasminogen, plasminogen activator Inhibitor-1 (PAI-1), thrombin-activatable fibrinolysis inhibitor (TAFI), and an in-house dynamic fibrin clot formation and lysis assay.Compared with normothermia, hypothermia significantly increased plasminogen activity (mean difference = 10.4%, 95% confidence interval [CI] 7.9-12.9), p < 0.001), PAI-1 levels (mean difference = 275 ng/mL, 95% CI 203-348, p < 0.001), and tPA levels (mean difference = 1.0 ng/mL, 95% CI 0.2-1.7, p = 0.01). No differences between hypothermia and normothermia were found in TAFI activity (p = 0.59) or in the fibrin D-dimer levels (p = 0.08). The fibrin clot lysis curves showed three different patterns: normal-, flat-, or resistant clot lysis curve. At hypothermia 45 (55%) patients had a resistant clot lysis curve and 33 (44%) patients had a resistant clot lysis curve at normothermia (p = 0.047). Comatose, resuscitated, cardiac arrest patients treated with hypothermia express an inhibited fibrinolysis even after rewarming. This could potentially increase the thromboembolic risk. ClinicalTrials.gov ID: NCT02258360.

The International Cardiac Arrest Research (I-CARE) Consortium Electroencephalography Database

Objective

To develop a harmonized multicenter clinical and electroencephalography (EEG) database for acute hypoxic-ischemic brain injury research involving patients with cardiac arrest.

Design

Multicenter cohort, partly prospective and partly retrospective.

Setting

Seven academic or teaching hospitals from the U.S. and Europe.

Patients

Individuals aged 16 or older who were comatose after return of spontaneous circulation following a cardiac arrest who had continuous EEG monitoring were included.

Interventions

not applicable.

Measurements and Main Results

Clinical and EEG data were harmonized and stored in a common Waveform Database (WFDB)-compatible format. Automated spike frequency, background continuity, and artifact detection on EEG were calculated with 10 second resolution and summarized hourly. Neurological outcome was determined at 3-6 months using the best Cerebral Performance Category (CPC) scale. This database includes clinical and 56,676 hours (3.9 TB) of continuous EEG data for 1,020 patients. Most patients died (N=603, 59%), 48 (5%) had severe neurological disability (CPC 3 or 4), and 369 (36%) had good functional recovery (CPC 1-2). There is significant variability in mean EEG recording duration depending on the neurological outcome (range 53-102h for CPC 1 and CPC 4, respectively). Epileptiform activity averaging 1 Hz or more in frequency for at least one hour was seen in 258 (25%) patients (19% for CPC 1-2 and 29% for CPC 3-5). Burst suppression was observed for at least one hour in 207 (56%) and 635 (97%) patients with CPC 1-2 and CPC 3-5, respectively.

Conclusions

The International Cardiac Arrest Research (I-CARE) consortium database provides a comprehensive real-world clinical and EEG dataset for neurophysiology research of comatose patients after cardiac arrest. This dataset covers the spectrum of abnormal EEG patterns after cardiac arrest, including epileptiform patterns and those in the ictal-interictal continuum.

Oxygen targets after cardiac arrest: a narrative review

A significant focus of post-resuscitation research over the last decade has included optimising oxygenation. This has primarily occurred due to an improved understanding of the possible harmful biological effects of high oxygenation, particularly the neurotoxicity of oxygen free radicals. Animal studies and some observational research in humans suggest harm with the occurrence of severe hyperoxaemia (PaO2 >300mmHg) in the post-resuscitation phase. This early data informed in a change in treatment recommendations, with the International Liaison Committee on Resuscitation (ILCOR) recommending the avoidance of hyperoxaemia. However, the optimal oxygenation level for maximal survival has not yet been determined. Recent Phase 3 randomised control trials (RCTs) provide further insight into when oxygen titration should occur. The EXACT RCT suggested that decreasing oxygen fraction post-resuscitation in the prehospital setting, with limited ability to titrate and measure oxygenation, is too soon. The BOX RCT, suggests delaying titration to a normal level in intensive care may be too late. While further RCTs are currently underway in ICU cohorts, titration of oxygen early after arrival at hospital should be considered.

Insufficient oxygen inhalation during cardiopulmonary resuscitation induces early changes in hemodynamics followed by late and unfavorable systemic responses in post-cardiac arrest rats

Cardiac arrest (CA) and concomitant post-CA syndrome lead to a lethal condition characterized by systemic ischemia-reperfusion injury. Oxygen (O₂ ) supply during cardiopulmonary resuscitation (CPR) is the key to success in resuscitation, but sustained hyperoxia can produce toxic effects post CA. However, only few studies have investigated the optimal duration and dosage of O₂ administration. Herein, we aimed to determine whether high concentrations of O₂ at resuscitation are beneficial or harmful. After rats were resuscitated from the 10-min asphyxia, mechanical ventilation was restarted at an FIO₂ of 1.0 or 0.3. From 10 min after initiating CPR, FIO₂ of both groups were maintained at 0.3. Bio-physiological parameters including O₂ consumption (VO₂ ) and mRNA gene expression in multiple organs were evaluated. The FIO₂ 0.3 group decreased VO₂ , delayed the time required to achieve peak MAP, lowered ejection fraction (75.1 ± 3.3% and 59.0 ± 5.7% with FIO₂ 1.0 and 0.3, respectively; p < .05), and increased blood lactate levels (4.9 ± 0.2 mmol/L and 5.6 ± 0.2 mmol/L, respectively; p < .05) at 10 min after CPR. FIO₂ 0.3 group had significant increases in hypoxia-inducible factor, inflammatory, and apoptosis-related mRNA gene expression in the brain. Likewise, significant upregulations of hypoxia-inducible factor and apoptosis-related gene expression were observed in the FIO₂ 0.3 group in the heart and lungs. Insufficient O₂ supplementation in the first 10 min of resuscitation could prolong ischemia, and may result in unfavorable biological responses 2 h after CA. Faster recovery from the impairment of O₂ metabolism might contribute to the improvement of hemodynamics during the early post-resuscitation phase; therefore, it may be reasonable to provide the maximum feasible O₂ concentrations during CPR.

Changes in Practice of Controlled Hypothermia after Cardiac Arrest in the Past 20 Years: A Critical Care Perspective

For 20 years, induced hypothermia and targeted temperature management have been recommended to mitigate brain injury and increase survival after cardiac arrest. On the basis of animal research and small clinical trials, the International Liaison Committee on Resuscitation strongly advocated hypothermia at 32-34 °C for 12-24 hours for comatose patients with out-of-hospital cardiac arrest with initial rhythm of ventricular fibrillation or nonperfusing ventricular tachycardia. The intervention was implemented worldwide. In the past decade, hypothermia and targeted temperature management have been investigated in larger clinical randomized trials focusing on target temperature depth, target temperature duration, prehospital versus in-hospital initiation, nonshockable rhythms, and in-hospital cardiac arrest. Systematic reviews suggest little or no effect of delivering the intervention on the basis of the summary of evidence, and the International Liaison Committee on Resuscitation today recommends only to treat fever and keep body temperature below 37.5 °C (weak recommendation, low-certainty evidence). Here we describe the evolution of temperature management for patients with cardiac arrest during the past 20 years and how the accrued evidence has influenced not only the recommendations but also the guideline process. We also discuss possible paths forward in this field, bringing up both whether fever management is at all beneficial for patients with cardiac arrest and which knowledge gaps future clinical trials in temperature management should address.

Association between sex and survival after out-of-hospital cardiac arrest: A systematic review and meta-analysis

The current literature on sex differences in 30-day survival following out-of-hospital cardiac arrest (OHCA) is conflicting, with 3 recent systematic reviews reporting opposing results. To address these contradictions, this systematic literature review and meta-analysis aimed to synthesize the literature on sex differences in survival after OHCA by including only population-based studies and through separate meta-analyses of crude and adjusted effect estimates. MEDLINE and Embase databases were systematically searched from inception to March 23, 2022 to identify observational studies reporting sex-specific 30-day survival or survival until hospital discharge after OHCA. Two meta-analyses were conducted. The first included unadjusted effect estimates of the association between sex and survival (comparing males vs females), whereas the second included effect estimates adjusted for possible mediating and/or confounding variables. The PROSPERO registration number was CRD42021237887, and the search identified 6712 articles. After the screening, 164 potentially relevant articles were identified, of which 26 were included. The pooled estimate for crude effect estimates (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.22-1.66) indicated that males have a higher chance of survival after OHCA than females. However, the pooled estimate for adjusted effect estimates shows no difference in survival after OHCA between males and females (OR, 0.93; 95% CI, 0.84-1.03). Both meta-analyses involved high statistical heterogeneity between studies: crude pooled estimate I2 = 95.7%, adjusted pooled estimate I2 = 91.3%. There does not appear to be a difference in survival between males and females when effect estimates are adjusted for possible confounding and/or mediating variables in non-selected populations.

A case of cardiac arrest due to postpartum hemorrhage treated with hysterectomy and extracorporeal membrane oxygenation

Although extracorporeal membrane oxygenation is relatively contraindicated in patients with severe disseminated intravascular coagulation (DIC), it can be safely introduced by providing adequate anti-DIC therapy.

Duration of cardiopulmonary resuscitation and phenotype of post-cardiac arrest brain injury

BACKGROUND

Patients resuscitated from cardiac arrest have variable severity of primary hypoxic ischemic brain injury (HIBI). Signatures of primary HIBI on brain imaging and electroencephalography (EEG) include diffuse cerebral edema and burst suppression with identical bursts (BSIB). We hypothesize distinct phenotypes of primary HIBI are associated with increasing cardiopulmonary resuscitation (CPR) duration.

METHODS

We identified from our prospective registry of both in-and out-of-hospital CA patients treated between January 2010 to January 2020 for this cohort study. We abstracted CPR duration, neurological examination, initial brain computed tomography gray to white ratio (GWR), and initial EEG pattern. We considered four phenotypes on presentation: awake; comatose with neither BSIB nor cerebral edema (non-malignant coma); BSIB; and cerebral edema (GWR ≤ 1.20). BSIB and cerebral edema were considered as non-mutually exclusive outcomes. We generated predicted probabilities of brain injury phenotype using localized regression.

RESULTS

We included 2,440 patients, of whom 545 (23%) were awake, 1,065 (44%) had non-malignant coma, 548 (23%) had BSIB and 438 (18%) had cerebral edema. Only 92 (4%) had both BSIB and edema. Median CPR duration was 16 [IQR 8-28] minutes. Median CPR duration increased in a stepwise manner across groups: awake 6 [3-13] minutes; non-malignant coma 15 [8-25] minutes; BSIB 21 [13-31] minutes; cerebral edema 32 [22-46] minutes. Predicted probability of phenotype changes over time.

CONCLUSIONS

Brain injury phenotype is related to CPR duration, which is a surrogate for severity of HIBI. The sequence of most likely primary HIBI phenotype with progressively longer CPR duration is awake, coma without BSIB or edema, BSIB, and finally cerebral edema.

Thiamine for the Treatment of Cardiac Arrest-Induced Neurological Injury: A Randomized, Blinded, Placebo-Controlled Experimental Study

Background Thiamine supplementation has demonstrated protective effects in a mouse model of cardiac arrest. The aim of this study was to investigate the neuroprotective effects of thiamine in a clinically relevant large animal cardiac arrest model. The hypothesis was that thiamine reduces neurological injury evaluated by neuron-specific enolase levels. Methods and Results Pigs underwent myocardial infarction and subsequently 9 minutes of untreated cardiac arrest. Twenty minutes after successful resuscitation, the pigs were randomized to treatment with either thiamine or placebo. All pigs underwent 40 hours of intensive care and were awakened for assessment of functional neurological outcome up until 9 days after cardiac arrest. Nine pigs were included in both groups, with 8 in each group surviving the entire intensive care phase. Mean area under the curve for neuron-specific enolase was similar between groups, with 81.5 μg/L per hour (SD, 20.4) in the thiamine group and 80.5 μg/L per hour (SD, 18.3) in the placebo group, with an absolute difference of 1.0 (95% CI, -57.8 to 59.8; P=0.97). Likewise, there were no absolute difference in neurological deficit score at the end of the protocol (2 [95% CI, -38 to 42]; P=0.93). There was no absolute mean group difference in lactate during the intensive care period (1.1 mmol/L [95% CI, -0.5 to 2.7]; P=0.16). Conclusions In this randomized, blinded, placebo-controlled trial using a pig cardiac arrest model with myocardial infarction and long intensive care and observation for 9 days, thiamine showed no effect in changes to functional neurological outcome or serum levels of neuron-specific enolase. Thiamine treatment had no effect on lactate levels after successful resuscitation.

Autoresuscitation after circulatory arrest: an updated systematic review

PURPOSE

Current practice in organ donation after death determination by circulatory criteria (DCD) advises a five-minute observation period following circulatory arrest, monitoring for unassisted resumption of spontaneous circulation (i.e., autoresuscitation). In light of newer data, the objective of this updated systematic review was to determine whether a five-minute observation time was still adequate for death determination by circulatory criteria.

SOURCE

We searched four electronic databases from inception to 28 August 2021, for studies evaluating or describing autoresuscitation events after circulatory arrest. Citation screening and data abstraction were conducted independently and in duplicate. We assessed certainty in evidence using the GRADE framework.

PRINCIPAL FINDINGS

Eighteen new studies on autoresuscitation were identified, consisting of 14 case reports and four observational studies. Most studies evaluated adults (n = 15, 83%) and patients with unsuccessful resuscitation following cardiac arrest (n = 11, 61%). Overall, autoresuscitation was reported to occur between one and 20 min after circulatory arrest. Among all eligible studies identified by our reviews (n = 73), seven observational studies were identified. In observational studies of controlled withdrawal of life-sustaining measures with or without DCD (n = 6), 19 autoresuscitation events were reported in 1,049 patients (incidence 1.8%; 95% confidence interval, 1.1 to 2.8). All resumptions occurred within five minutes of circulatory arrest and all patients with autoresuscitation died.

CONCLUSION

A five-minute observation time is sufficient for controlled DCD (moderate certainty). An observation time greater than five minutes may be needed for uncontrolled DCD (low certainty). The findings of this systematic review will be incorporated into a Canadian guideline on death determination.

STUDY REGISTRATION

PROSPERO (CRD42021257827); registered 9 July 2021.

Elucidation of ALG10B as a Novel Long-QT Syndrome-Susceptibility Gene

BACKGROUND

Long-QT syndrome (LQTS) is characterized by QT prolongation and increased risk for syncope, seizures, and sudden cardiac death. The majority of LQTS stems from pathogenic mutations in KCNQ1, KCNH2, or SCN5A. However, ≈10% of patients with LQTS remain genetically elusive. We utilized genome sequencing to identify a novel LQTS genetic substrate in a multigenerational genotype-negative LQTS pedigree.

METHODS

Genome sequencing was performed on 5 affected family members. Only rare nonsynonymous variants present in all affected family members were considered. The candidate variant was characterized functionally in patient-derived induced pluripotent stem cell and gene-edited, variant corrected, isogenic control induced pluripotent stem cell-derived cardiomyocytes.

RESULTS

A missense variant (p.G6S) was identified in ALG10B-encoded α-1,2-glucosyltransferase B protein. ALG10B (alpha-1,2-glucosyltransferase B protein) is a known interacting protein of KCNH2-encoded Kv11.1 (HERG [human Ether-à-go-go-related gene]). Compared with isogenic control, ALG10B-p.G6S induced pluripotent stem cell-derived cardiomyocytes showed (1) decreased protein expression of ALG10B (p.G6S, 0.7±0.18, n=8 versus control, 1.25±0.16, n=9; P<0.05), (2) significant retention of HERG in the endoplasmic reticulum (P<0.0005), and (3) a significantly prolonged action potential duration confirmed by both patch clamp (p.G6S, 531.1±38.3 ms, n=15 versus control, 324.1±21.8 ms, n=13; P<0.001) and multielectrode assay (P<0.0001). Lumacaftor-a compound known to rescue HERG trafficking-shortened the pathologically prolonged action potential duration of ALG10B-p.G6S induced pluripotent stem cell-derived cardiomyocytes by 10.6% (n=31 electrodes; P<0.001).

CONCLUSIONS

Here, we demonstrate that ALG10B-p.G6S downregulates ALG10B, resulting in defective HERG trafficking and action potential duration prolongation. Therefore, ALG10B is a novel LQTS-susceptibility gene underlying the LQTS phenotype observed in a multigenerational pedigree. ALG10B mutation analysis may be warranted, especially in genotype-negative patients with an LQT2-like phenotype.

Diastolic Blood Pressure Threshold During Pediatric Cardiopulmonary Resuscitation and Survival Outcomes: A Multicenter Validation Study

OBJECTIVES

Arterial diastolic blood pressure (DBP) greater than 25 mm Hg in infants and greater than 30 mm Hg in children greater than 1 year old during cardiopulmonary resuscitation (CPR) was associated with survival to hospital discharge in one prospective study. We sought to validate these potential hemodynamic targets in a larger multicenter cohort.

DESIGN

Prospective observational study.

SETTING

Eighteen PICUs in the ICU-RESUScitation prospective trial from October 2016 to March 2020.

PATIENTS

Children less than or equal to 18 years old with CPR greater than 30 seconds and invasive blood pressure (BP) monitoring during CPR.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Invasive BP waveform data and Utstein-style CPR data were collected, including prearrest patient characteristics, intra-arrest interventions, and outcomes. Primary outcome was survival to hospital discharge, and secondary outcomes were return of spontaneous circulation (ROSC) and survival to hospital discharge with favorable neurologic outcome. Multivariable Poisson regression models with robust error estimates evaluated the association of DBP greater than 25 mm Hg in infants and greater than 30 mm Hg in older children with these outcomes. Among 1,129 children with inhospital cardiac arrests, 413 had evaluable DBP data. Overall, 85.5% of the patients attained thresholds of mean DBP greater than or equal to 25 mm Hg in infants and greater than or equal to 30 mm Hg in older children. Initial return of circulation occurred in 91.5% and 25% by placement on extracorporeal membrane oxygenator. Survival to hospital discharge occurred in 58.6%, and survival with favorable neurologic outcome in 55.4% (i.e. 94.6% of survivors had favorable neurologic outcomes). Mean DBP greater than 25 mm Hg for infants and greater than 30 mm Hg for older children was significantly associated with survival to discharge (adjusted relative risk [aRR], 1.32; 1.01-1.74; p = 0.03) and ROSC (aRR, 1.49; 1.12-1.97; p = 0.002) but did not reach significance for survival to hospital discharge with favorable neurologic outcome (aRR, 1.30; 0.98-1.72; p = 0.051).

CONCLUSIONS

These validation data demonstrate that achieving mean DBP during CPR greater than 25 mm Hg for infants and greater than 30 mm Hg for older children is associated with higher rates of survival to hospital discharge, providing potential targets for DBP during CPR.

Association between scene time interval and clinical outcomes according to key Utstein factors in out-of-hospital cardiac arrest

There is no consensus on the appropriate length of time spent on the scene by emergency medical services. Hence, our study aimed to investigate the association between the scene time interval (STI) and clinical outcomes of out-of-hospital cardiac arrest (OHCA) and determine whether this association is affected by key Utstein factors-witness status, bystander cardiopulmonary resuscitation, and initial electrocardiogram rhythm. This study is a cross-sectional study, using data between 2017 and 2020 from a nationwide, population-based, prospective registry of OHCA. The primary exposure is the STI, which was categorized into 3 groups: short (0 < STI ≤ 12 min), middle (13 ≤ STI ≤ 16 min), long (17 ≤ STI ≤ 30 min). The main outcome was good neurological recovery. Multivariable logistic regression and interaction analyses were performed to estimate the effect of STIs on study outcomes according to key Utstein factors. Witnessed, bystander cardiopulmonary resuscitation, and an initial shockable rhythm were associated with high survival to discharge and good neurological recovery, whereas prolonged STI was associated with low survival to discharge and poor neurological recovery. In patients with witnessed arrest, increased STI caused a more rapid decrease in survival to discharge than in non-witnessed cases (witnessed arrest: 0.56 (0.51-0.62) in middle STI and 0.33 (0.30-0.37) in long STI, non-witnessed arrest: 0.72 (0.61-0.85) in middle STI and 0.53 (0.45-0.62) in long STI. In patients with an initial shockable rhythm, increased STI caused a more rapid decrease in survival to discharge and neurological recovery than in initial non-shockable cases. Longer STIs were associated with poorer OHCA outcomes, and this trend was further emphasized in patients with witnessed OHCA and OHCA with an initial shockable rhythm.

Recurrent Out-of-Hospital Sudden Cardiac Arrest: Prevalence and Clinical Factors

BACKGROUND

Despite improvements in management following survival from sudden cardiac arrest (SCA) and wide availability of implantable cardioverter defibrillators for secondary prevention, a subgroup of individuals will suffer multiple distinct episodes of SCA. The objective of this study was to characterize and evaluate the burden of recurrent out-of-hospital SCA among survivors of SCA in a single large US community.

METHODS

SCA cases were prospectively ascertained in the Oregon Sudden Unexpected Death Study. Individuals that experienced recurrent SCA were identified both prospectively and retrospectively.

RESULTS

We ascertained 6649 individuals with SCA (2002-2020) and 924 (14%) survived to hospital discharge. Of these, 88 survivors (10%) experienced recurrent SCA. Of the nonsurvivors (n=5725), 35 had suffered a recurrent SCA. Of the total 123 SCA cases with recurrent SCA, >60% occurred at least 1 year after the initial SCA (median 23 months, range: 6 days to 31 years). SCA occurred despite a secondary prevention implantable cardioverter defibrillator in 22% (n=26). Prevalence of coronary disease (36% versus 25%), hypertension (69% versus 43%), diabetes (44% versus 21%), and chronic kidney disease (35% versus 14%) was significantly higher in recurrent SCA versus single SCA survivors (n=80, P=0.01). Among individuals with no secondary prevention implantable cardioverter defibrillators before recurrent SCA, the majority had apparently reversible etiologies identified at initial SCA, with one-quarter undergoing coronary revascularization and over half diagnosed with noncoronary cardiac etiologies.

CONCLUSIONS

At least 10% of SCA survivors had recurrent SCA, and a large subgroup suffered their repeat SCA despite treatment for an apparently reversible etiology. A renewed focus on careful assessment of cardiac substrate as well as management of coronary disease, hypertension, diabetes, and chronic kidney disease in SCA survivors could reduce recurrent SCA.

Serum total cholesterol level as a potential predictive biomarker for neurological outcomes in cardiac arrest survivors who underwent target temperature management

Cholesterol is an essential substance to maintain cell membranes. Low levels of total cholesterol (TC) are associated with poor prognosis in critically ill patients. Cardiac arrest-induced whole-body ischemia and reperfusion injury cause a sepsis-like syndrome. The Cholesterol level in post-cardiac arrest patients may indicate the degree of endotoxemia or inflammation caused by ischemic and reperfusion injury. We aimed to investigate the association of TC levels with neurologic outcome of out-of-hospital cardiac arrest (OHCA) survivors who underwent target temperature management (TTM). This was a retrospective single-center observational study from May 2018 to April 2021 on a cohort of 106 patients. TC levels were determined in samples obtained immediately and at 24, 48, and 72 hours after the return of spontaneous circulation (ROSC). The primary outcome was poor neurologic outcome at 3 months after ROSC. Poor neurologic outcome was defined by cerebral performance categories 3 to 5. Sixty patients had a poor neurologic outcome. TC levels were significantly lower in the poor neurologic outcome group at each time point. The TC levels for predicting poor neurologic outcome had a sensitivity of 80.8%, with 67.6% specificity at 48 hours (TC48) after ROSC. The areas under the curve value of TC48 was 0.771 (0.670-0.853), with a cutoff value of 114 mg/dL. TC level at 48 hours after ROSC was a helpful marker for the 3-month poor neurologic outcome. This might be an easily accessible predictive marker of neurologic outcome in OHCA survivors treated with TTM.

Temperature Control After In-Hospital Cardiac Arrest: A Randomized Clinical Trial

BACKGROUND

This study was conducted to determine the effect of hypothermic temperature control after in-hospital cardiac arrest (IHCA) on mortality and functional outcome as compared with normothermia.

METHODS

An investigator initiated, open-label, blinded-outcome-assessor, multicenter, randomized controlled trial comparing hypothermic temperature control (32-34°C) for 24 h with normothermia after IHCA in 11 hospitals in Germany. The primary endpoint was all-cause mortality after 180 days. Secondary end points included in-hospital mortality and favorable functional outcome using the Cerebral Performance Category scale after 180 days. A Cerebral Performance Category score of 1 or 2 was defined as a favorable functional outcome.

RESULTS

A total of 1055 patients were screened for eligibility and 249 patients were randomized: 126 were assigned to hypothermic temperature control and 123 to normothermia. The mean age of the cohort was 72.6±10.4 years, 64% (152 of 236) were male, 73% (166 of 227) of cardiac arrests were witnessed, 25% (57 of 231) had an initial shockable rhythm, and time to return of spontaneous circulation was 16.4±10.5 minutes. Target temperature was reached within 4.2±2.8 hours after randomization in the hypothermic group and temperature was controlled for 48 hours at 37.0°±0.9°C in the normothermia group. Mortality by day 180 was 72.5% (87 of 120) in hypothermic temperature control arm, compared with 71.2% (84 of 118) in the normothermia group (relative risk, 1.03 [95% CI, 0.79-1.40]; P=0.822). In-hospital mortality was 62.5% (75 of 120) in the hypothermic temperature control as compared with 57.6% (68 of 118) in the normothermia group (relative risk, 1.11 [95% CI, 0.86-1.46, P=0.443). Favorable functional outcome (Cerebral Performance Category 1 or 2) by day 180 was 22.5% (27 of 120) in the hypothermic temperature control, compared with 23.7% (28 of 118) in the normothermia group (relative risk, 1.04 [95% CI, 0.78-1.44]; P=0.822). The study was prematurely terminated because of futility.

CONCLUSIONS

Hypothermic temperature control as compared with normothermia did not improve survival nor functional outcome at day 180 in patients presenting with coma after IHCA. The HACA in-hospital trial (Hypothermia After Cardiac Arrest in-hospital) was underpowered and may have failed to detect clinically important differences between hypothermic temperature control and normothermia.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique Identifier: NCT00457431.

Association between Early Phase Serum Albumin Levels and Outcomes of Post-Cardiac Arrest Patients: A Systematic Review and Meta-Analysis

We aimed to evaluate early phase serum albumin levels in and outcomes of resuscitated patients after cardiac arrest. Medline, EMBASE, and the Cochrane Library were systematically searched until 4 July 2022, for studies on post-cardiac arrest patients and involving measurement of early phase albumin levels and assessment of in-hospital mortality or neurologic outcomes. Two reviewers independently assessed the methodological quality of the included studies using the Quality in Prognosis Studies tool. We included 3837 patients from seven observational studies in this systematic review and meta-analysis. The serum albumin level was significantly higher in survivors than in non-survivors, showing a positive association with an overall standardized mean difference (SMD) [(mean value of non-survivors—mean value of survivors)/pooled standard deviation] of 0.55 (95% confidence interval [CI], 0.48−0.62; I2 = 0%; p < 0.001). Additionally, the serum albumin level was significantly higher in the good neurologic outcome group than in the poor neurologic outcome group (four studies; SMD = 1.01, 95% CI = 0.49−1.52, I2 = 87%; p < 0.001). Relatively low serum albumin levels in the early phase may be associated with in-hospital mortality of resuscitated patients after cardiac arrest. However, we could not evaluate the association between albumin level and neurologic outcome because of limited included studies and unresolved high heterogeneity.