Temporal Trends in End-Tidal Capnography and Outcomes in Out-of-Hospital Cardiac Arrest: A Secondary Analysis of a Randomized Clinical Trial.

Importance: While widely measured, the time-varying association between exhaled end-tidal carbon dioxide (EtCO2) and out-of-hospital cardiac arrest (OHCA) outcomes is unclear.

Objective: To evaluate temporal associations between EtCO2 and return of spontaneous circulation (ROSC) in the Pragmatic Airway Resuscitation Trial (PART).

Design, Setting, And Participants: This study was a secondary analysis of a cluster randomized trial performed at multicenter emergency medical services agencies from the Resuscitation Outcomes Consortium.

Spontaneous Repolarization Alternans Causes VT/VF Rearrest That Is Suppressed by Preserving Gap Junctions.

Background: Ventricular tachycardia (VT)/ventricular fibrillation (VF) rearrest after successful resuscitation is common, and survival is poor. A mechanism of VT/VF, as demonstrated in ex vivo studies, is when repolarization alternans becomes spatially discordant (DIS ALT), which can be enhanced by impaired gap junctions (GJs). However, in vivo spontaneous DIS ALT-induced VT/VF has never been demonstrated, and the effects of GJ on DIS ALT and VT/VF rearrest are unknown.

Statewide implementation of the cardiac arrest registry to enhance survival in Ohio.

Objective: Public health surveillance is essential for improving community health. The Cardiac Arrest Registry to Enhance Survival (CARES) is a surveillance system for out-of-hospital cardiac arrest (OHCA). We describe results of the organized statewide implementation of Ohio CARES.

Methods for calculating ventilation rates during resuscitation from out-of-hospital cardiac arrest.

Objective: Ventilation control is important during resuscitation from out-of-hospital cardiac arrest (OHCA). We compared different methods for calculating ventilation rates (VR) during OHCA.

Methods: We analyzed data from the Pragmatic Airway Resuscitation Trial, identifying ventilations through capnogram recordings.

Level I Hyperglycemia Alert: A Case Report.

Introduction: Nonketotic hyperglycemia-associated chorea is a rare condition that upon presentation to the emergency department can be easily misdiagnosed as a seizure or a stroke. Although uncommon, identification of this condition can aid emergency physicians in avoiding unnecessary and potentially harmful treatments for other neurological pathology. Furthermore, prompt hyperglycemic control can result in reversal of symptoms within days.

Assessment of intensive care unit-free and ventilator-free days as alternative outcomes in the pragmatic airway resuscitation trial.

Objective: We sought to evaluate the utility and validity of ICU-free days and ventilator-free days as candidate outcomes for OHCA trials.

Methods: We conducted a secondary analysis of the Pragmatic Airway Resuscitation Trial. We determined ICU-free (days alive and out of ICU during the first 30 days) and ventilator-free days (days alive and without mechanical ventilation).

Neighborhood-level out-of-hospital cardiac arrest risk and the impact of local CPR interventions.

Introduction: It is unclear how best to identify "high-risk" areas for out-of-hospital cardiac arrest (OHCA) and if neighborhood-level interventions improve bystander cardiopulmonary resuscitation (BCPR). Our objectives were to 1) identify and compare community characteristics between high and low-risk neighborhoods; and 2) examine change in BCPR after a targeted hands-only CPR intervention.

Methods: This was a cross-sectional analysis of OHCA events in Franklin County, Ohio between 1/1/2010-12/31/2017.

Airway strategy and ventilation rates in the pragmatic airway resuscitation trial.

Background: We sought to describe ventilation rates during out-of-hospital cardiac arrest (OHCA) resuscitation and their associations with airway management strategy and outcomes.

Methods: We analyzed continuous end-tidal carbon dioxide capnography data from adult OHCA enrolled in the Pragmatic Airway Resuscitation Trial (PART). Using automated signal processing techniques, we determined continuous ventilation rates for consecutive 10-second epochs after airway insertion.

External validation of Pittsburgh Cardiac Arrest Category illness severity score.

Unlabelled: Early prognostication post-cardiac arrest can help determine appropriate medical management and help evaluate effectiveness of post-arrest interventions. The Pittsburgh Cardiac Arrest Category (PCAC) severity score is a 4-level illness severity score found to strongly predict patient outcomes in both in- (IHCA) and out-of-hospital cardiac arrests (OHCA). We aimed to validate the PCAC severity score in an external cohort of cardiac arrest patients.

Novel application of thoracic impedance to characterize ventilations during cardiopulmonary resuscitation in the pragmatic airway resuscitation trial.

Background: Significant challenges exist in measuring ventilation quality during out-of-hospital cardiopulmonary arrest (OHCA) outcomes. Since ventilation is associated with outcomes in cardiac arrest, tools that objectively describe ventilation dynamics are needed. We sought to characterize thoracic impedance (TI) oscillations associated with ventilation waveforms in the Pragmatic Airway Resuscitation Trial (PART).

Hypothermia Modulates Arrhythmia Substrates During Different Phases of Resuscitation From Ischemic Cardiac Arrest.

Background: We designed an innovative porcine model of ischemia-induced arrest to determine dynamic arrhythmia substrates during focal infarct, global ischemia from ventricular tachycardia or fibrillation (VT/VF) and then reperfusion to determine the effect of therapeutic hypothermia (TH) on dynamic arrhythmia substrates and resuscitation outcomes.

Methods And Results: Anesthetized adult pigs underwent thoracotomy and regional plunge electrode placement in the left ventricle. Subjects were then maintained at either control (CT; 37°C, n=9) or TH (33°C, n=8).

Mild hypothermia preserves myocardial conduction during ischemia by maintaining gap junction intracellular communication and Na channel function.

Acute cardiac ischemia induces conduction velocity (CV) slowing and conduction block, promoting reentrant arrhythmias leading to sudden cardiac arrest. Previously, we found that mild hypothermia (MH; 32°C) attenuates ischemia-induced conduction block and CV slowing in a canine model of early global ischemia. Acute ischemia impairs cellular excitability and the gap junction (GJ) protein connexin (Cx)43.

Phosphorylation at Connexin43 Serine-368 Is Necessary for Myocardial Conduction During Metabolic Stress.

Connexin43 (Cx43) phosphorylation alters gap junction localization and function. In particular, phosphorylation at serine-368 (S368) has been suggested to alter gap junctional conductance, but previous reports have shown inconsistent results for both timing and functional effects of S368 phosphorylation. The objective of this study was to determine the functional effects of isolated S368 phosphorylation.

Atrial SERCA2a Overexpression Has No Affect on Cardiac Alternans but Promotes Arrhythmogenic SR Ca2+ Triggers.

Background: Atrial fibrillation (AF) is the most common arrhythmia in humans, yet; treatment has remained sub-optimal due to poor understanding of the underlying mechanisms. Cardiac alternans precede AF episodes, suggesting an important arrhythmia substrate. Recently, we demonstrated ventricular SERCA2a overexpression suppresses cardiac alternans and arrhythmias.