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.

Temperature Management for Comatose Adult Survivors of Cardiac Arrest: A Science Advisory From the American Heart Association.

Targeted temperature management has been a cornerstone of post-cardiac arrest care for patients remaining unresponsive after return of spontaneous circulation since the initial trials in 2002 found that mild therapeutic hypothermia improves neurological outcome. The suggested temperature range expanded in 2015 in response to a large trial finding that outcomes were not better with treatment at 33° C compared with 36° C. In 2021, another large trial was published in which outcomes with temperature control at 33° C were not better than those of patients treated with a strategy of strict normothermia. On the basis of these new data, the International Liaison Committee on Resuscitation and other organizations have altered their treatment recommendations for temperature management after cardiac arrest. The new American Heart Association guidelines on this topic will be introduced in a 2023 focused update. To provide guidance to clinicians while this focused update is forthcoming, the American Heart Association's Emergency Cardiovascular Care Committee convened a writing group to review the TTM2 trial (Hypothermia Versus Normothermia After Out-of-Hospital Cardiac Arrest) in the context of other recent evidence and to present an opinion on how this trial may influence clinical practice. This science advisory was informed by review of the TTM2 trial, consideration of other recent influential studies, and discussion between cardiac arrest experts in the fields of cardiology, critical care, emergency medicine, and neurology. Conclusions presented in this advisory statement do not replace current guidelines but are intended to provide an expert opinion on novel literature that will be incorporated into future guidelines and suggest the opportunity for reassessment of current clinical practice.

Sudden Cardiac Arrest Survivorship: A Scientific Statement From the American Heart Association.

Cardiac arrest systems of care are successfully coordinating community, emergency medical services, and hospital efforts to improve the process of care for patients who have had a cardiac arrest. As a result, the number of people surviving sudden cardiac arrest is increasing. However, physical, cognitive, and emotional effects of surviving cardiac arrest may linger for months or years. Systematic recommendations stop short of addressing partnerships needed to care for patients and caregivers after medical stabilization. This document expands the cardiac arrest resuscitation system of care to include patients, caregivers, and rehabilitative healthcare partnerships, which are central to cardiac arrest survivorship.

Relationship Between Duration of Targeted Temperature Management, Ischemic Interval, and Good Functional Outcome From Out-of-Hospital Cardiac Arrest.

OBJECTIVES: Tailoring hypothermia duration to ischemia duration may improve outcome from out-of-hospital cardiac arrest. We investigated the association between the hypothermia/ischemia ratio and functional outcome in a secondary analysis of data from the Resuscitation Outcomes Consortium Amiodarone, Lidocaine, or Placebo Study trial. DESIGN: Cohort study of out-of-hospital cardiac arrest patients screened for Resuscitation Outcomes Consortium-Amiodarone, Lidocaine, or Placebo Study. SETTING: Multicenter study across North America. PATIENTS: Adult, nontraumatic, out-of-hospital cardiac arrest patients screened for Resuscitation Outcomes Consortium-Amiodarone, Lidocaine, or Placebo Study who survived to hospital admission and received targeted temperature management between May 2012 and October 2015. INTERVENTIONS: Targeted temperature management in comatose survivors of out-of-hospital cardiac arrest. We defined hypothermia/ischemia ratio as total targeted temperature management time (initiation through rewarming) divided by calculated total ischemia time (approximate time of arrest [9-1-1 call or emergency medical services-witnessed] to return of spontaneous circulation). MEASUREMENTS AND MAIN RESULTS: The primary outcome was hospital survival with good functional status (modified Rankin Score, 0-3) at hospital discharge. We fitted logistic regression models to estimate the association between hypothermia/ischemia ratio and the primary outcome, adjusting for demographics, arrest characteristics, and Resuscitation Outcomes Consortium enrolling site. A total of 3,429 patients were eligible for inclusion, of whom 36.2% were discharged with good functional outcome. Patients had a mean age of 62.0 years (SD, 15.8), with 69.7% male, and 58.0% receiving lay-rescuer cardiopulmonary resuscitation. Median time to return of spontaneous circulation was 21.1 minutes (interquartile range, 16.1-26.9), and median duration of targeted temperature management was 32.9 hours (interquartile range, 23.7-37.8). A total of 2,579 had complete data and were included in adjusted regression analyses. After adjustment for patient characteristics and Resuscitation Outcomes Consortium site, a greater hypothermia/ischemia ratio was associated with increased survival with good functional outcome (odds ratio, 2.01; 95% CI, 1.82-2.23). This relationship, however, appears to be primarily driven by time to return of spontaneous circulation in this patient cohort. CONCLUSIONS: Although a larger hypothermia/ischemia ratio was associated with good functional outcome after out-of-hospital cardiac arrest in this cohort, this association is primarily driven by duration of time to return of spontaneous circulation. Tailoring duration of targeted temperature management based on duration of time to return of spontaneous circulation or patient characteristics requires prospective study.

Glycated Hemoglobin is Associated with Glycemic Control and 6-Month Neurologic Outcome in Cardiac Arrest Survivors Undergoing Therapeutic Hypothermia.

BACKGROUND: Glucose control status after cardiac arrest depending on chronic glycemic status and the association between chronic glycemic status and outcome in cardiac arrest survivors are not well known. We investigated the association between glycated hemoglobin (HbA1c) and 6-month neurologic outcome in cardiac arrest survivors undergoing therapeutic hypothermia (TH) and whether mean glucose, area under curve (AUC) of glucose during TH, and neuron-specific enolase (NSE) are different between normal and high HbA1c groups. METHODS: This retrospective single-center study included adult comatose cardiac arrest survivors who underwent TH from September 2011 to December 2017. HbA1c and glucose were measured after return of spontaneous circulation (ROSC), and normal or high HbA1c was defined using cutoff value of 6.4% of HbA1c. Blood glucose was measured at least every 4 h and treated with a written protocol to maintain the range of 80-200 mg/dL. Hypoglycemia and hyperglycemia were defined with glucose < 70 or > 180 mg/dL. Mean glucose during induction and rewarming phase and AUC of glucose during every 6 h of maintenance were calculated, and NSE at 48 h after cardiac arrest was recorded. The primary outcome was unfavorable neurologic outcome, defined as Glasgow Pittsburgh Cerebral Performance Category scale 3-5 at 6 months after cardiac arrest. RESULTS: Of 384 included patients, 81 (21.1%) had high HbA1c and 247 (64.3%) had an unfavorable neurologic outcome. Patients with high HbA1c were more common in the unfavorable group than in favorable group (27.5% vs 9.5%, p < 0.001), and the unfavorable group had significantly higher HbA1c level (5.8% [5.4-6.8%] vs 5.6% [5.3-6.0%], p = 0.007). HbA1c level was independently associated with worse neurologic outcome (odds ratio 1.414; 95% confidence interval 1.051-1.903). High HbA1c group had higher glucose after ROSC, glucose AUC during maintenance, and rewarming phase than normal HbA1c group. High HbA1c group had significantly higher incidence of hyperglycemia throughout the TH, while normal HbA1c group had significantly higher incidence of normoglycemia. However, no glucose parameter remained as an independent predictor of neurologic outcome after adjustment, irrespective of HbA1c level. NSE showed good prognostic performance (area under curve 0.892; cutoff value 26.3 ng/mL). Although NSE level was not different between HbA1c groups, high HbA1c group had higher proportion of patient having NSE over cutoff. CONCLUSIONS: Higher HbA1c was independently associated with unfavorable neurologic outcome. Glycemic status during TH was different between normal and high HbA1c groups.

Phenotyping Cardiac Arrest: Bench and Bedside Characterization of Brain and Heart Injury Based on Etiology.

OBJECTIVES: Cardiac arrest etiology may be an important source of between-patient heterogeneity, but the impact of etiology on organ injury is unknown. We tested the hypothesis that asphyxial cardiac arrest results in greater neurologic injury than cardiac etiology cardiac arrest (ventricular fibrillation cardiac arrest), whereas ventricular fibrillation cardiac arrest results in greater cardiovascular dysfunction after return of spontaneous circulation. DESIGN: Prospective observational human and randomized animal study. SETTING: University laboratory and ICUs. PATIENTS: Five-hundred forty-three cardiac arrest patients admitted to ICU. SUBJECTS: Seventy-five male Sprague-Dawley rats. INTERVENTIONS: We examined neurologic and cardiovascular injury in Isoflurane-anesthetized rat cardiac arrest models matched by ischemic time. Hemodynamic and neurologic outcomes were assessed after 5 minutes no flow asphyxial cardiac arrest or ventricular fibrillation cardiac arrest. Comparison was made to injury patterns observed after human asphyxial cardiac arrest or ventricular fibrillation cardiac arrest. MEASUREMENTS AND MAIN RESULTS: In rats, cardiac output (20 ± 10 vs 45 ± 9 mL/min) and pH were lower and lactate higher (9.5 ± 1.0 vs 6.4 ± 1.3 mmol/L) after return of spontaneous circulation from ventricular fibrillation cardiac arrest versus asphyxial cardiac arrest (all p < 0.01). Asphyxial cardiac arrest resulted in greater early neurologic deficits, 7-day neuronal loss, and reduced freezing time (memory) after conditioned fear (all p < 0.05). Brain antioxidant reserves were more depleted following asphyxial cardiac arrest. In adjusted analyses, human ventricular fibrillation cardiac arrest was associated with greater cardiovascular injury based on peak troponin (7.8 ng/mL [0.8-57 ng/mL] vs 0.3 ng/mL [0.0-1.5 ng/mL]) and ejection fraction by echocardiography (20% vs 55%; all p < 0.0001), whereas asphyxial cardiac arrest was associated with worse early neurologic injury and poor functional outcome at hospital discharge (n = 46 [18%] vs 102 [44%]; p < 0.0001). Most ventricular fibrillation cardiac arrest deaths (54%) were the result of cardiovascular instability, whereas most asphyxial cardiac arrest deaths (75%) resulted from neurologic injury (p < 0.0001). CONCLUSIONS: In transcending rat and human studies, we find a consistent phenotype of heart and brain injury after cardiac arrest based on etiology: ventricular fibrillation cardiac arrest produces worse cardiovascular dysfunction, whereas asphyxial cardiac arrest produces worsened neurologic injury associated with greater oxidative stress.

Association Between Duration of Resuscitation and Favorable Outcome After Out-of-Hospital Cardiac Arrest: Implications for Prolonging or Terminating Resuscitation.

BACKGROUND: Little evidence guides the appropriate duration of resuscitation in out-of-hospital cardiac arrest, and case features justifying longer or shorter durations are ill defined. We estimated the impact of resuscitation duration on the probability of favorable functional outcome in out-of-hospital cardiac arrest using a large, multicenter cohort. METHODS: This was a secondary analysis of a North American, single-blind, multicenter, cluster-randomized, clinical trial (ROC-PRIMED [Resuscitation Outcomes Consortium Prehospital Resuscitation Using an Impedance Valve and Early Versus Delayed]) of consecutive adults with nontraumatic, emergency medical services-treated out-of-hospital cardiac arrest. Primary exposure was duration of resuscitation in minutes (onset of professional resuscitation to return of spontaneous circulation [ROSC] or termination of resuscitation). Primary outcome was survival to hospital discharge with favorable outcome (modified Rankin scale [mRS] score of 0-3). Subjects were additionally classified as survival with unfavorable outcome (mRS score of 4-5), ROSC without survival (mRS score of 6), or without ROSC. Subject accrual was plotted as a function of resuscitation duration, and the dynamic probability of favorable outcome at discharge was estimated for the whole cohort and subgroups. Adjusted logistic regression models tested the association between resuscitation duration and survival with favorable outcome. RESULTS: The primary cohort included 11 368 subjects (median age, 69 years [interquartile range, 56-81 years]; 7121 men [62.6%]). Of these, 4023 (35.4%) achieved ROSC, 1232 (10.8%) survived to hospital discharge, and 905 (8.0%) had an mRS score of 0 to 3 at discharge. Distribution of cardiopulmonary resuscitation duration differed by outcome (P<0.00001). For cardiopulmonary resuscitation duration up to 37.0 minutes (95% confidence interval, 34.9-40.9 minutes), 99% with an eventual mRS score of 0 to 3 at discharge achieved ROSC. The dynamic probability of an mRS score of 0 to 3 at discharge declined over elapsed resuscitation duration, but subjects with initial shockable cardiac rhythm, witnessed cardiac arrest, and bystander cardiopulmonary resuscitation were more likely to survive with favorable outcome after prolonged efforts (30-40 minutes). After adjustment for prehospital (odds ratio, 0.93; 95% confidence interval, 0.92-0.95) and inpatient (odds ratio, 0.97; 95% confidence interval, 0.95-0.99) covariates, resuscitation duration was associated with survival to discharge with an mRS score of 0 to 3. CONCLUSIONS: Shorter resuscitation duration was associated with likelihood of favorable outcome at hospital discharge. Subjects with favorable case features were more likely to survive prolonged resuscitation up to 47 minutes. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov. Unique identifier: NCT00394706.

Clinically distinct electroencephalographic phenotypes of early myoclonus after cardiac arrest.

OBJECTIVE: We tested the hypothesis that there are readily classifiable electroencephalographic (EEG) phenotypes of early postanoxic multifocal myoclonus (PAMM) that develop after cardiac arrest. METHODS: We studied a cohort of consecutive comatose patients treated after cardiac arrest from January 2012 to February 2015. For patients with clinically evident myoclonus before awakening, 2 expert physicians reviewed and classified all EEG recordings. Major categories included: Pattern 1, suppression-burst background with high-amplitude polyspikes in lockstep with myoclonic jerks; and Pattern 2, continuous background with narrow, vertex spike-wave discharges in lockstep with myoclonic jerks. Other patterns were subcortical myoclonus and unclassifiable. We compared population characteristics and outcomes across these EEG subtypes. RESULTS: Overall, 401 patients were included, of whom 69 (16%) had early myoclonus. Among these patients, Pattern 1 was the most common, occurring in 48 patients (74%), whereas Pattern 2 occurred in 8 patients (12%). The remaining patients had subcortical myoclonus (n = 2, 3%) or other patterns (n = 7, 11%). No patients with Pattern 1, subcortical myoclonus, or other patterns survived with favorable outcome. By contrast, 4 of 8 patients (50%) with Pattern 2 on EEG survived, and 4 of 4 (100%) survivors had favorable outcomes despite remaining comatose for 1 to 2 weeks postarrest. INTERPRETATION: Early PAMM is common after cardiac arrest. We describe 2 distinct patterns with distinct prognostic significances. For patients with Pattern 1 EEGs, it may be appropriate to abandon our current clinical standard of aggressive therapy with conventional antiepileptic therapy in favor of early limitation of care or novel neuroprotective strategies. Ann Neurol 2016;80:175-184.

Temperature management for out-of-hospital cardiac arrest.

More than 300,000 Americans suffer a cardiac arrest outside of the hospital each year and even among those who are successfully resuscitated and survive to hospital admission, outcomes remain poor. Temperature management (previously known as therapeutic hypothermia) is the only intervention that has been reproducibly demonstrated to ameliorate the neurologic injury that follows cardiac arrest. The results of a recent large randomized controlled trial have highlighted the uncertainty about temperature management strategies following cardiac arrest. This article reviews the issues and recommendations.

Serum Neutrophil Gelatinase-Associated Lipocalin Predicts Survival After Resuscitation From Cardiac Arrest.

OBJECTIVES: In the first days after cardiac arrest, accurate prognostication is challenging. Serum biomarkers are a potentially attractive adjunct for prognostication and risk stratification. Our primary objective in this exploratory study was to identify novel early serum biomarkers that predict survival after cardiac arrest earlier than currently possible. DESIGN: Prospective, observational study. SETTING: A single academic medical center. SUBJECTS: Adult subjects who sustained cardiac arrest with return of spontaneous circulation. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: We obtained blood samples from each subject at enrollment, 6, 12, 24, 48, and 72 hours after return of spontaneous circulation. We measured the serum levels of novel biomarkers, including neutrophil gelatinase-associated lipocalin, high-mobility group protein B1, intracellular cell adhesion molecule-1, and leptin, as well as previously characterized biomarkers, including neuron-specific enolase and S100B protein. Our primary outcome of interest was survival-to-hospital discharge. We compared biomarker concentrations at each time point between survivors and nonsurvivors and used logistic regression to test the unadjusted associations of baseline clinical characteristics and enrollment biomarker levels with survival. Finally, we constructed a series of adjusted models to explore the independent association of each enrollment biomarker level with survival. A total of 86 subjects were enrolled. Enrollment levels of high-mobility group protein B1, neutrophil gelatinase-associated lipocalin, and S100B were higher in nonsurvivors than survivors. Enrollment leptin, neuron-specific enolase, and intracellular cell adhesion molecule-1 levels did not differ between nonsurvivors and survivors. The discriminatory power of enrollment neutrophil gelatinase-associated lipocalin level was the greatest (c-statistic, 0.78 [95% CI, 0.66-0.90]) and remained stable across all time points. In our adjusted models, enrollment neutrophil gelatinase-associated lipocalin level was independently associated with survival even after controlling for the development of acute kidney injury, and its addition to clinical models improved overall predictive accuracy. CONCLUSIONS: Serum neutrophil gelatinase-associated lipocalin levels are strongly predictive of survival-to-hospital discharge after cardiac arrest.

Effect of Two Work-to-Rest Ratios on Cardiovascular, Thermal, and Perceptual Responses During Fire Suppression and Recovery.

OBJECTIVE: Fire suppression is a physically demanding occupation that often results in significant heat stress and hypohydration. Guidelines for the number of work intervals allowed before a structured recovery were consensus derived and have not been tested. METHODS: Apparently healthy firefighters were recruited for this field study. Subjects were assigned to two or three bouts of live fire training prior to 20 minutes of structured recovery to provide rehydration and cooling. After recovery, the subjects completed a timed test of firefighting skills. RESULTS: Extending the fire suppression interval from two to three work periods before a structured recovery period increased core temperature and the time required to perform a high intensity circuit of firefighting skills immediately following recovery. A mild hypotension was noted during recovery but the groups did not differ for blood pressure, heart rate, or firefighter perception of thermal strain or exertion. CONCLUSIONS: This is the first study to examine the physiologic effects of structural firefighting work intervals on recovery and subsequent performance. Both groups experienced maximal cardiovascular strain during fire suppression but extending the work interval worsened heat stress and negatively affected certain aspects of performance immediately following the recovery period.

Emergency Incident Rehabilitation: Resource Document to the Position Statement of the National Association of EMS Physicians.

Position Statement: Emergency Incident Rehabilitation The National Association of EMS Physicians® believes that: Emergency operations and training conducted while wearing protective clothing and respirators is physiologically and cognitively demanding. The heat stress and fatigue created by working in protective clothing and respirators creates additional risk of illness/injury for the public safety provider. Emergency incident rehabilitation provides a structured rest period for rehydration and correction of abnormal body core temperature following work in protective clothing and respirators. Emergency incident rehab should be conducted at incidents (e.g. fireground, hazardous materials, and heavy rescue emergencies) and trainings involving activities that may lead to exceeding safe levels of physical and mental exertion. Emergency incident rehabilitation is incident care, not fitness for duty, and meant to reduce physiologic strain and prepare the responder to return to duty at the current incident and for the remainder of the shift. EMS should play a role in emergency incident rehabilitation with providers trained to understand the physiologic response of healthy individuals to environmental, exertional, and cognitive stress and implement appropriate mitigation strategies. An appropriately qualified physician should have oversight over the creation and implementation of emergency incident rehabilitation protocols and may be separate from the roles and responsibilities of the occupational medicine physician. There are no peer-reviewed data related to cold weather rehabilitation. Future studies should address this limitation to the literature.

Pilot Study Examining the Effects of Atropine on Performance during Uncompensable Heat Stress.

UNLABELLED: In many operational scenarios, hypohydration can be corrected with oral rehydration following the work interval. Although rare, there are potential situations that require extended intervals of uncompensable heat stress exposure while working in personal protective equipment (PPE). Under these conditions, retention of body water may be valuable to preserve work capacity and reduce cardiovascular strain. We conducted a pilot study comparing intramuscular atropine sulfate versus saline placebo to establish the safety profile of the protocol and to provide pilot data for future investigations. Five, healthy, heat-acclimated subjects completed this crossover design laboratory study. Each subject performed up to one hour of exertion in a hot environment while wearing a chemical resistant coverall. Atropine sulfate (0.02 mg/kg) or an equivalent volume of sterile saline was administered by intramuscular injection. Core temperature, heart rate, perceptual measures, and changes in body mass were measured. All five subjects completed the acclimation period and both protocols. No adverse events occurred, and no pharmacologically induced delirium was identified. Change in body mass was less following exercise influenced by atropine sulfate (p = 0.002). Exertion time tended to be longer in the atropine sulfate arm (p = 0.08). Other measures appeared similar between groups. Intramuscular atropine sulfate reduced sweating and tended to increase the work interval under uncompensable heat stress when compared to saline placebo. Heart rate and temperature changes during exertion were similar in both conditions suggesting that the influence of an anticholinergic agent on thermoregulation may be minimal during uncompensable heat stress. KEY WORDS: thermoregulation; cholinolytic; anticholinergic; reaction time.

Group-Based Trajectory Modeling of Suppression Ratio After Cardiac Arrest.

BACKGROUND: Existing studies of quantitative electroencephalography (qEEG) as a prognostic tool after cardiac arrest (CA) use methods that ignore the longitudinal pattern of qEEG data, resulting in significant information loss and precluding analysis of clinically important temporal trends. We tested the utility of group-based trajectory modeling (GBTM) for qEEG classification, focusing on the specific example of suppression ratio (SR). METHODS: We included comatose CA patients hospitalized from April 2010 to October 2014, excluding CA from trauma or neurological catastrophe. We used Persyst®v12 to generate SR trends and used semi-quantitative methods to choose appropriate sampling and averaging strategies. We used GBTM to partition SR data into different trajectories and regression associate trajectories with outcome. We derived a multivariate logistic model using clinical variables without qEEG to predict survival, then added trajectories and/or non-longitudinal SR estimates, and assessed changes in model performance. RESULTS: Overall, 289 CA patients had ≥36 h of EEG yielding 10,404 h of data (mean age 57 years, 81 % arrested out-of-hospital, 33 % shockable rhythms, 31 % overall survival, 17 % discharged to home or acute rehabilitation). We identified 4 distinct SR trajectories associated with survival (62, 26, 12, and 0 %, P < 0.0001 across groups) and CPC (35, 10, 4, and 0 %, P < 0.0001 across groups). Adding trajectories significantly improved model performance compared to adding non-longitudinal data. CONCLUSIONS: Longitudinal analysis of continuous qEEG data using GBTM provides more predictive information than analysis of qEEG at single time-points after CA.

Reintubation in critically ill patients: procedural complications and implications for care.

INTRODUCTION: In critically ill patients, re-intubation is common and may be a high-risk procedure. Anticipating a difficult airway and identifying high-risk patients can allow time for life-saving preparation. Unfortunately, prospective studies have not compared the difficulty or complication rates associated with reintubation in this population. METHODS: We performed a secondary analysis of a prospective registry of in-hospital emergency airway management, focusing on patients that underwent multiple out-of-operating room intubations during a single hospitalization. Our main outcomes of interest were technical difficulty of intubation (number of attempts, need for adjuncts to direct laryngoscopy, best Cormack-Lehane grade and training level of final intubator) and the frequency of procedural complications (aspiration, arrhythmia, airway trauma, new hypotension, new hypoxia, esophageal intubation and cardiac arrest). We compared the cohort of reintubated patients to a matched cohort of singly intubated patients and compared each repeatedly intubated patient's first and last intubation. RESULTS: Our registry included 1053 patients, of which 151 patients (14%) were repeatedly intubated (median two per patient). Complications were significantly more common during last intubation compared to first (13% versus 5%, P = 0.02). The most common complications were hypotension (41%) and hypoxia (35%). These occurred despite no difference in any measure of technical difficultly across intubations. CONCLUSION: In this cohort of reintubated patients, clinically important procedural complications were significantly more common on last intubation compared to first.

Successful treatment of metoprolol-induced cardiac arrest with high-dose insulin, lipid emulsion, and ECMO.

ß-Adrenergic antagonist toxicity causes cardiovascular collapse often refractory to standard therapy. Alternative therapies include high-dose insulin, lipid emulsion, and venoarterial extracorporeal membrane oxygenation (VA-ECMO). A 47-year-old man ingested 10 g of metoprolol tartrate in a suicide attempt. Upon emergency department presentation, he was comatose, bradycardic, and hypotensive. Glucagon (14 mg IV) and vasopressor/inotropic support (epinephrine 0.1 µg/[kg min], dobutamine 10 µg/[kg min]) were administered. Despite these therapies, he developed cardiac arrest for 55 minutes, requiring epinephrine (5 mg IV) and vasopressin (40 U IV) with multiple episodes of return of spontaneous circulation. Additional vasopressor administration (vasopressin 0.04 U/min, norepinephrine 0.5 µg/[kg min]) did not improve his hemodynamics. High-dose insulin (250 U IV) and 20% lipid emulsion (100 mL bolus with 200 mL/30 min infusion) were administered, and VA-ECMO was initiated with hemodynamic improvement. His postarrest neurologic examination demonstrated lack of brainstem reflexes and cortical motor response. He awoke 11.5 hours after time of ingestion. Venoarterial extracorporeal membrane oxygenation was discontinued at hospital day 3, and the patient was discharged on hospital day 10 with excellent neurologic recovery. A serum metoprolol level measured 25,000 ng/mL (therapeutic 20-340 ng/mL). High-dose insulin has been shown to be beneficial in ß-adrenergic antagonist cardiotoxicity. Lipid emulsion is thought to act as a lipid extractor, lowering serum and tissue levels. Venoarterial extracorporeal membrane oxygenation was used with the above therapies, restoring organ perfusion and allowing intrinsic drug metabolism and elimination. High-dose insulin, lipid emulsion, and VA-ECMO should be considered for refractory cardiac arrest secondary to ß-adrenergic antagonist toxicity such as metoprolol.

Emergency Neurological Life Support: Resuscitation Following Cardiac Arrest.

Cardiac arrest is the most common cause of death in North America. Neurocritical care interventions, including targeted temperature management (TTM), have significantly improved neurological outcomes in patients successfully resuscitated from cardiac arrest. Therefore, resuscitation following cardiac arrest was chosen as an emergency neurological life support protocol. Patients remaining comatose following resuscitation from cardiac arrest should be considered for TTM. This protocol will review induction, maintenance, and re-warming phases of TTM, along with management of TTM side effects. Aggressive shivering suppression is necessary with this treatment to ensure the maintenance of a target temperature. Ancillary testing, including electrocardiography, computed tomography and/or magnetic resonance imaging of the brain, continuous electroencephalography monitoring, and correction of electrolyte, blood gas, and hematocrit changes, are also necessary to optimize outcomes.

Duration of resuscitation efforts and functional outcome after out-of-hospital cardiac arrest: when should we change to novel therapies?

BACKGROUND: Functionally favorable survival remains low after out-of-hospital cardiac arrest. When initial interventions fail to achieve the return of spontaneous circulation, they are repeated with little incremental benefit. Patients without rapid return of spontaneous circulation do not typically survive with good functional outcome. Novel approaches to out-of-hospital cardiac arrest have yielded functionally favorable survival in patients for whom traditional measures had failed, but the optimal transition point from traditional measures to novel therapies is ill defined. Our objective was to estimate the dynamic probability of survival and functional recovery as a function of resuscitation effort duration to identify this transition point. METHODS AND RESULTS: Retrospective cohort study of a cardiac arrest database at a single site. We included 1014 adult (≥18 years) patients experiencing nontraumatic out-of-hospital cardiac arrest between 2005 and 2011, defined as receiving cardiopulmonary resuscitation or defibrillation from a professional provider. We stratified by functional outcome at hospital discharge (modified Rankin scale). Survival to hospital discharge was 11%, but only 6% had a modified Rankin scale of 0 to 3. Within 16.1 minutes of cardiopulmonary resuscitation, 89.7% (95% confidence interval, 80.3%-95.8%) of patients with good functional outcome had achieved return of spontaneous circulation, and the probability of good functional recovery fell to 1%. Adjusting for prehospital and inpatient covariates, cardiopulmonary resuscitation duration (minutes) is independently associated with favorable functional status at hospital discharge (odds ratio, 0.84; 95% confidence interval, 0.72-0.98; P=0.02). CONCLUSIONS: The probability of survival to hospital discharge with a modified Rankin scale of 0 to 3 declines rapidly with each minute of cardiopulmonary resuscitation. Novel strategies should be tested early after cardiac arrest rather than after the complete failure of traditional measures.

Initial lactate and lactate change in post-cardiac arrest: a multicenter validation study.

OBJECTIVE: Rate of lactate change is associated with in-hospital mortality in post-cardiac arrest patients. This association has not been validated in a prospective multicenter study. The objective of the current study was to determine the association between percent lactate change and outcomes in post-cardiac arrest patients. DESIGN: Four-center prospective observational study conducted from June 2011 to March 2012. SETTING: The National Post-Arrest Research Consortium is a clinical research network conducting research in post-cardiac arrest care. The network consists of four urban tertiary care teaching hospitals. PATIENTS: Inclusion criteria consisted of adult out-of-hospital non-traumatic cardiac arrest patients who were comatose after return of spontaneous circulation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was survival to hospital discharge, and secondary outcome was good neurologic outcome. We compared the absolute lactate levels and the differences in the percent lactate change over 24 hours between survivors and nonsurvivors and between subjects with good and bad neurologic outcomes. One hundred patients were analyzed. The median age was 63 years (interquartile range, 50-75) and 40% were female. Ninety-seven percent received therapeutic hypothermia, and overall survival was 46%. Survivors and patients with good neurologic outcome had lower lactate levels at 0, 12, and 24 hours (p< 0.01). In adjusted models, percent lactate decrease at 12 hours was greater in survivors (odds ratio, 2.2; 95% CI, 1.1-6.2) and in those with good neurologic outcome (odds ratio, 2.2; 95% CI, 1.1-4.4). CONCLUSION: Lower lactate levels at 0, 12, and 24 hours and greater percent decrease in lactate over the first 12 hours post cardiac arrest are associated with survival and good neurologic outcome.