Integrating rSO2 and EEG monitoring in cardiopulmonary resuscitation: A novel methodology.

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.

AWAreness during REsuscitation - II: A multi-center study of consciousness and awareness in cardiac arrest.

INTRODUCTION: 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: In a prospective 25-site in-hospital study, we incorporated a) independent audiovisual testing of awareness, including explicit and implicit learning using a computer and headphones, with b) continuous real-time electroencephalography(EEG) and cerebral oxygenation(rSO2) 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: Of 567 IHCA, 53(9.3%) survived, 28 of these (52.8%) completed interviews, and 11(39.3%) reported CA memories/perceptions suggestive of consciousness. Four categories of experiences emerged: 1) emergence from coma during CPR (CPR-induced consciousness [CPRIC]) 2/28(7.1%), or 2) in the post-resuscitation period 2/28(7.1%), 3) dream-like experiences 3/28(10.7%), 4) transcendent recalled experience of death (RED) 6/28(21.4%). In the cross-sectional arm, 126 community CA survivors' experiences reinforced these categories and identified another: delusions (misattribution of medical events). Low survival limited the ability to examine for implicit learning. Nobody identified the visual image, 1/28(3.5%) identified the auditory stimulus. Despite marked cerebral ischemia (Mean rSO2 = 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).

Guidelines and standards for the study of death and recalled experiences of death--a multidisciplinary consensus statement and proposed future directions.

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.

Clinical characteristics and outcomes of in-hospital cardiac arrest among patients with and without COVID-19.

AIMS: To define outcomes of patients with COVID-19 compared to patients without COVID-19 suffering in-hospital cardiac arrest (IHCA). MATERIALS AND METHODS: We performed a single-center retrospective study of IHCA cases. Patients with COVID-19 were compared to consecutive patients without COVID-19 from the prior year. Return of spontaneous circulation (ROSC), 30-day survival, and cerebral performance category (CPC) at 30-days were assessed. RESULTS: Fifty-five patients with COVID-19 suffering IHCA were identified and compared to 55 consecutive IHCA patients in 2019. The COVID-19 cohort was more likely to require vasoactive agents (67.3% v 32.7%, p = 0.001), invasive mechanical ventilation (76.4% v 23.6%, p < 0.001), renal replacement therapy (18.2% v 3.6%, p = 0.029) and intensive care unit care (83.6% v 50.9%, p = 0.001) prior to IHCA. Patients with COVID-19 had shorter CPR duration (10 min v 22 min, p = 0.002). ROSC (38.2% v 49.1%, p = 0.336) and 30-day survival (20% v 32.7%, p = 0.194) did not differ. A 30-day cerebral performance category of 1 or 2 was more common among non-COVID patients (27.3% v 9.1%, p = 0.048). CONCLUSIONS: Return of spontaneous circulation and 30-day survival were similar between IHCA patients with and without COVID-19. Compared to previously published data, we report greater ROSC and 30-day survival after IHCA in COVID-19.