Faculty Bibliography

BACKGROUND:In-hospital cardiac arrest (IHCA) continues to be associated with high morbidity and mortality. The objective of this study was to study the association of arterial carbon dioxide tension (PaCO2) on survival to discharge and favorable neurologic outcome in adults with IHCA. METHODS:The study population included 353 adults who underwent resuscitation from 2011 to 2021 for IHCA at an academic tertiary medical center with arterial blood gas testing done within 24 hours of arrest. Outcomes of interest included survival to discharge and favorable neurologic outcome, defined as Glasgow Outcome Score of 4-5. RESULTS:Of the 353 patients studied, PaCO2 classification included: hypocapnia (PaCO2 < 35mmg, n=89), normocapnia (PaCO2 35-45mmHg, n=151), and hypercapnia (PaCO2 > 45mmHg, n=113). Hypercapnic patients were further divided into mild (45mmHg < PaCO2 ≤ 55mmHg, n=62) and moderate/severe hypercapnia (PaCO2 > 55mmHg, n=51). Patients with normocapnia had the highest rates of survival to hospital discharge (52.3% vs 32.6% vs 30.1%, p<0.001) and favorable neurologic outcome (35.8% vs 25.8% vs 17.9%, p=0.005) compared those with hypocapnia and hypercapnia respectively. In multivariable analysis, compared to normocapnia, hypocapnia (OR 2.06, 95%CI 1.15-3.70) and hypercapnia (OR 2.67, 95%CI 1.53-4.66) were both found to be independently associated with higher rates of in-hospital mortality. Compared to normocapnia, while mild hypercapnia (OR 2.53, 95%CI 1.29-4.97) and moderate/severe hypercapnia (OR 2.86, 95%CI 1.35-6.06) were both independently associated with higher in-hospital mortality compared to normocapnia, moderate/severe hypercapnia was also independently associated with lower rates of favorable neurologic outcome (OR 0.28, 95%CI 0.11-0.73), while mild hypercapnia was not. CONCLUSION/CONCLUSIONS:In this prospective registry of adults with IHCA, hypercapnia noted within 24 hours after arrest was independently associated with lower rates of survival to discharge and favorable neurologic outcome.

Despite improvements in cardiopulmonary resuscitation (CPR), survival and neurologic recovery after cardiac arrest remain poor due to ischemia and subsequent reperfusion injury. As the likelihood of survival and favorable neurologic outcome decreases with increasing severity of ischemia during CPR, developing methods to measure the magnitude of ischemia during resuscitation is critical for improving overall outcomes. Cerebral oximetry, which measures regional cerebral oxygen saturation (rSO₂) by near-infrared spectroscopy, has emerged as a potentially beneficial marker of cerebral ischemia during CPR. In numerous preclinical and clinical studies, higher rSO₂ during CPR has been associated with improved cardiac arrest survival and neurologic outcome. There is also emerging evidence that this can be integrated with electroencephalogram (EEG) monitoring to provide a bimodal system of brain monitoring during CPR. In this method's review, we discuss the feasibility, application, and implications of this integrated monitoring approach, highlighting its significance for improving clinical outcomes in cardiac arrest management and guiding future research directions.

INTRODUCTION/UNASSIGNED:Physiology-guided cardiopulmonary resuscitation (CPR) offers the potential to optimize resuscitation and enable early prognosis. METHODS/UNASSIGNED:Physiology-Guided CPR was one of six focus topic for the Wolf Creek XVII Conference held on June 14-17, 2023 in Ann Arbor, Michigan, USA. International thought leaders and scientists in the field of cardiac arrest resuscitation from academia and industry were invited. Participants submitted via online survey knowledge gaps, barriers to translation and research priorities for each focus topic. Expert panels used the survey results and their own perspectives and insights to create and present a preliminary unranked list for each category, which was then debated, revised and ranked by all attendees to identify the top 5 for each category. RESULTS/UNASSIGNED:Top knowledge gaps include identifying optimal strategies for the evaluation of physiology-guided CPR and the optimal values for existing patients using patient outcomes. The main barriers to translation are the limited usability outside of critical care environments and the training and equipment required for monitoring. The top research priorities are the development of clinically feasible and reliable methods to continuously and non-invasively monitor physiology during CPR and prospective human studies proving targeting parameters during CPR improves outcomes. CONCLUSION/UNASSIGNED:Physiology-guided CPR has the potential to provide individualized resuscitation and move away from a one-size-fits-all approach. Current understanding is limited, and clinical trials are lacking. Future developments need to consider the clinical application and applicability of measurement to all healthcare settings. Therefore, clinical trials using physiology-guided CPR for individualisation of resuscitation efforts are needed.

INTRODUCTION/BACKGROUND:Cognitive activity and awareness during cardiac arrest (CA) are reported but ill understood. This first of a kind study examined consciousness and its underlying electrocortical biomarkers during cardiopulmonary resuscitation (CPR). METHODS:) monitoring into CPR during in-hospital CA (IHCA). Survivors underwent interviews to examine for recall of awareness and cognitive experiences. A complementary cross-sectional community CA study provided added insights regarding survivors' experiences. RESULTS:=43%) normal EEG activity (delta, theta and alpha) consistent with consciousness emerged as long as 35-60 minutes into CPR. CONCLUSIONS:Consciousness. awareness and cognitive processes may occur during CA. The emergence of normal EEG may reflect a resumption of a network-level of cognitive activity, and a biomarker of consciousness, lucidity and RED (authentic "near-death" experiences).

Episodes of lucidity (ELs) in Alzheimer's disease and Alzheimer's disease-related dementias (AD/ADRD), have garnered increasing attention as an important area of research. Efforts to study lucidity suffer from a lack of clear definitional criteria, inconsistent conceptualization, and diverse approaches to operationalizing features of these events. To advance systematic investigation of ELs in AD/ADRD, there is a need for clarity and precision in labeling event attributes, markers, and specific measurement strategies that enable operational harmonization across distinct approaches to investigating the relatively broad and nascent phenomenon. To that end, we propose a preliminary research framework to guide harmonization of approaches to investigating ELs in AD/ADRD. Our goal is to provide an initial schematic that encourages uniform labeling of operational decisions about ELs.

Background/UNASSIGNED:There are increasing numbers of reports of cognitive activity, consciousness, awareness and recall related to cardiopulmonary resuscitation (CPR) and interventions such as the use of sedative and analgesic drugs during CPR. Objectives/UNASSIGNED:This scoping review aims to describe the available evidence concerning CPR-related cognitive activity, consciousness, awareness and recall and interventions such as the use of sedative and analgesic drugs during CPR. Methods/UNASSIGNED:A literature search was conducted of Medline, Embase and CINAHL from inception to 21 October 2021. We included case studies, observational studies, review studies and grey literature. Results/UNASSIGNED:We identified 8 observational studies including 40,317 patients and 464 rescuers, and 26 case reports including 33 patients. The reported prevalence of CPR-induced consciousness was between 0.23% to 0.9% of resuscitation attempts, with 48-59% of experienced professional rescuers surveyed estimated to have observed CPR-induced consciousness. CPR-induced consciousness is associated with professional rescuer CPR, witnessed arrest, a shockable rhythm, increased return of spontaneous circulation (ROSC), and survival to hospital discharge when compared to patients without CPR-induced consciousness. Few studies of sedation for CPR-induced consciousness were identified. Although local protocols for treating CPR-induced consciousness exist, there is no widely accepted guidance. Conclusions/UNASSIGNED:CPR-related cognitive activity, consciousness, awareness and recall is uncommon but increasingly reported by professional rescuers. The data available was heterogeneous in nature and not suitable for progression to a systematic review process. Although local treatment protocols exist for management of CPR-induced consciousness, there are no widely accepted treatment guidelines. More studies are required to investigate the management of CPR-induced consciousness.

An inadvertent consequence of advances in stem cell research, neuroscience, and resuscitation science has been to enable scientific insights regarding what happens to the human brain in relation to death. The scientific exploration of death is in large part possible due to the recognition that brain cells are more resilient to the effects of anoxia than assumed. Hence, brain cells become irreversibly damaged and "die" over hours to days postmortem. Resuscitation science has enabled life to be restored to millions of people after their hearts had stopped. These survivors have described a unique set of recollections in relation to death that appear universal. We review the literature, with a focus on death, the recalled experiences in relation to cardiac arrest, post-intensive care syndrome, and related phenomena that provide insights into potential mechanisms, ethical implications, and methodologic considerations for systematic investigation. We also identify issues and controversies related to the study of consciousness and the recalled experience of cardiac arrest and death in subjects who have been in a coma, with a view to standardize and facilitate future research.