Post-cardiac arrest syndrome: epidemiology, pathophysiology, treatment, and prognostication. A consensus statement from the International Liaison Committee on Resuscitation (American Heart Association, Australian and New Zealand Council on Resuscitation, European Resuscitation Council, Heart and Stroke Foundation of Canada, InterAmerican Heart Foundation, Resuscitation Council of Asia, and the Resuscitation Council of Southern Africa); the American Heart Association Emergency Cardiovascular Care Committee; the Council on Cardiovascular Surgery and Anesthesia; the Council on Cardiopulmonary, Perioperative, and Critical Care; the Council on Clinical Cardiology; and the Stroke Council

Successful extracorporeal membrane oxygenation for heart failure after adolescent idiopathic scoliosis surgery

PURPOSE

Spine surgery, particularly deformity correction, is associated with a high risk of peri-operative or post-operative complications, and these complications can lead to catastrophic consequences. This case report will present the etiology and treatment process of the peri-operative cardiac arrest during scoliosis correction surgery.

METHOD

In this report, we present a case of cardiac arrest during posterior correction surgery in a 17-year-old female patient with adolescent idiopathic scoliosis.

RESULTS

The patient was successfully treated using extracorporeal membrane oxygenation and an intra-aortic balloon pump. We have discussed the potential causes of peri-operative cardiac arrest, including thromboembolism (VAE/PE), electrolyte imbalance (Hyper/Hypokalemia or Acidosis), hypovolemia, hypothermia, and cardiogenic shock related to neurogenic-stunned myocardium.

CONCLUSION

There are many etiologies should be considered in peri-operative cardiac arrest during posterior correction spine surgery, such as venous air embolism and electrolyte imbalance. Stress cardiomyopathy, which occurs after stressful conditions, such as surgery should also be considered. Surgeons must consider these etiologies when faced with critical situations, and the successful treatment of such cases relies on team collaboration and prompt intervention.

Cardiac arrest after hanging: A scoping review

BACKGROUND

Hanging is a common cause of suicide and asphyxial cardiac arrest. There are few data to inform the treatment of cardiac arrest after hanging. We designed a scoping review to describe evidence relating to interventions and outcomes in patients with and without cardiac arrest after hanging.

METHODS

Medline, Embase and Cochrane were searched from inception to 05/12/2024. Titles and abstracts were screened, and duplicates were removed. Articles were eligible for inclusion if they studied non-judicial hanging in adults or children, included cardiac arrest patients and provided functional or survival outcomes.

RESULTS

The search retrieved 855 articles. One hundred and nineteen references underwent full-text review. Forty-five studies were included in the review. Studies were mainly from high-income countries and were all observational. There was variation in the terminology for hanging and in the outcomes reported. Survival with favourable functional outcome was rare in patients with cardiac arrest after hanging but was very common in patients without cardiac arrest. Cervical spine, airway and vascular injuries were rare. No studies identified interventions that were associated with improved survival following return of spontaneous circulation.

CONCLUSION

There are few data to inform treatment of patients with cardiac arrest after hanging. The available data suggest that cardiac arrest is a critical determinant of poor outcome following hanging. Further research should uniformly report outcomes of patients with cardiac arrest after hanging based on the Utstein template.

Electrophysiological Signatures of Alpha Coma

PURPOSE

Recent research on quantitative EEG in coma has proposed several metrics correlating with consciousness level. However, the heterogeneous nature of coma can challenge the generalizability of these measures. This study investigates alpha-coma, an electroclinical pattern characterized by a widespread, nonreactive alpha rhythm often linked to poor outcomes. The aim was to quantify the electrophysiological features of alpha-coma and compare them to the alpha rhythm in awake controls, seeking clearer insights into quantitative EEG analysis in comatose states.

METHODS

Fourteen alpha-coma patients were retrospectively selected from University Hospitals of Geneva and age-matched with 14 healthy control subjects from an open-source dataset. EEG data were preprocessed and analyzed to extract power spectra, spectral decay (aperiodic activity), sample entropy, and functional connectivity.

RESULTS

Alpha-coma patients did not differ in alpha power but exhibited significantly higher levels of spectral decay ( p < 0.001), suggesting a convergence toward an inhibitory state. Sample entropy was significantly higher in alpha-coma patients ( p = 0.01), indicating an increase in the cortical complexity in alpha-coma compared with healthy subjects.

CONCLUSIONS

Alpha-coma shows increased aperiodic activity and EEG complexity, despite similar alpha power and clustering coefficient. The increased aperiodic activity aligns with findings in other comatose patients, including those sedated or with subcortical dysfunction. However, the increased entropy contradicts existing literature, suggesting that alpha-coma may represent a state of widespread cortical dysfunction likely resulting from nonhierarchical, turbulent brain activity. This indicates that the loss of consciousness does not guarantee consistent cortical measures across the whole spectrum of EEG patterns.

Hemodynamic Characteristics and Prognostic Implication of Modified Society for Cardiovascular Angiography and Interventions Shock Classification in Comatose Patients With Out-of-Hospital Cardiac Arrest

BACKGROUND

Cardiogenic shock complicating acute myocardial infarction is associated with a high mortality rate. Cardiogenic shock after out-of-hospital cardiac arrest (OHCA) can be due to transient myocardial stunning but also reflect the increasing severity of ongoing heart failure. The Society for Cardiovascular Angiography and Interventions (SCAI) proposed a division of cardiogenic shock into 5 phenotypes, with cardiac arrest being a modifier. The objective was to apply SCAI shock classification to a well-characterized OHCA population and describe the hemodynamic characteristics and prognostic significance of increasing SCAI classes.

METHODS AND RESULTS

This is a post hoc analysis of data from the BOX (Blood Pressure and Oxygenation Targets in Post Resuscitation Care) trial of comatose patients with OHCA. Patients were classified according to SCAI class upon hospital admission. Invasive arterial and pulmonary arterial measurements were obtained the first 72 hours after admission, and perfusion pressure, cardiac index and cardiac power output were calculated. Of 789 patients included, 31.6% were classified as SCAI class B/C, 29.9% as SCAI class D, and 38.5% as SCAI class E. The first recorded perfusion pressure differed between SCAI class B/C, D, and E being lower in higher SCAI classes. The difference was found only at the first measurement. Cardiac index and cardiac power output did not differ at any time point between classes. The 1-year mortality rate increased with SCAI Class B/C to E (21.3%, 34.3%, and 48.4%, respectively; P<0.001).

CONCLUSIONS

The 1-year mortality rate after OHCA increased with increasing SCAI classes, but cardiac index, cardiac power output, and perfusion pressure remained notably similar in the first 72 hours after admission. This challenges whether all OHCAs should be recorded as SCAI class E by default.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03141099.

Revascularization During Cardiac Arrest While Receiving Extracorporeal Life Support in Patients With Acute Myocardial Infarction

Background

Extracorporeal cardiopulmonary resuscitation (ECPR) has allowed patients with refractory out-of-hospital cardiac arrest (OHCA) due to acute myocardial infarction (AMI) to receive primary percutaneous coronary intervention (PCI); they were previously ineligible.

Objectives

The purpose of this study was to clarify the characteristics and outcomes of patients with OHCA secondary to AMI who underwent primary PCI during refractory cardiac arrest despite ECPR.

Methods

Patients with AMI and OHCA aged ≥18 years who underwent PCI with ECPR in 2013 to 2018 were identified from a multicenter ECPR registry in Japan. The primary outcome was in-hospital mortality. We also assessed possible predictors of survival to discharge using mixed effects logistic regression to account for group differences among facilities.

Results

Among 671 patients with AMI and OHCA who underwent PCI with ECPR from 30 institutions, 251 (37%) patients had refractory cardiac arrest despite ECPR initiation and subsequently underwent primary PCI. Following coronary reperfusion, 64.9% (163/251) of patients achieved the sustained return of spontaneous circulation (ROSC), 21.1% (53/251) survived, and 10.4% (26/251) had favorable neurological status at hospital discharge. Multivariable analysis revealed that intermittent prehospital ROSC (OR: 5.22; 95% CI: 1.54-17.79), shorter time to ECPR initiation (OR: 0.89; 95% CI: 0.82-0.98), and postprocedural TIMI flow grade 3 (OR: 5.08; 95% CI: 1.50-17.22) are significantly associated with survival to hospital discharge.

Conclusions

Among patients with AMI and refractory OHCA treated with ECPR, one-third did not have sustained ROSC prior to PCI. Of those, two-thirds achieved sustained ROSC following reperfusion and one-fifth survived to discharge.

Mixed Cardiogenic-Vasodilatory Shock: Current Insights and Future Directions

This state-of-the-art review describes the potential etiologies, pathophysiology, and management of mixed shock in the context of a proposed novel classification system. Cardiogenic-vasodilatory shock occurs when cardiogenic shock is complicated by inappropriate vasodilation, impairing compensatory mechanisms, and contributing to worsening shock. Vasodilatory-cardiogenic shock occurs when vasodilatory shock is complicated by myocardial dysfunction, resulting in low cardiac output. Primary mixed shock occurs when a systemic insult triggers both myocardial dysfunction and vasoplegia. Regardless of the etiology of mixed shock, the hemodynamic profile can be similar, and outcomes tend to be poor. Identification and treatment of both the initial and complicating disease processes is essential along with invasive hemodynamic monitoring given the evolving nature of mixed shock states. Hemodynamic support typically involves a combination of inotropes and vasopressors, with few data available to guide the use of mechanical circulatory support. Consensus definitions and novel treatment strategies are needed for this dangerous condition.

Thoughts on recent articles on cardiopulmonary resuscitation

Comments were made on some thought-provoking articles, which included articles that dealt with cardiac arrest (CA). Two articles on CA elaborate on the role of automated compression devices to provide chest compressions during cardiopulmonary resuscitation (CPR) in "hostile" environments and on a predictive model in cases of out-of-hospital CA (OHCA). CPR after CA has been practiced for centuries, and the evolution until current modern-day practices are discussed. The delay in adopting efficient techniques of resuscitation by the medical community for decades is also touched upon. Both in-hospital and OHCA are discussed along with guidelines and strategies to improve outcomes. Areas of possible research in the future are mentioned.

Early Albumin Administration in Veno-Arterial Extracorporeal Membrane Oxygenation

BACKGROUND

The clinical outcome and fluid balance of patients with veno-arterial extracorporeal membrane oxygenation (VA ECMO) or after extracorporeal cardiopulmonary resuscitation (eCPR) may be improved by addressing the high fluid demand with an early albumin administration.

METHODS

In this prospective observational study, patients supported with VA ECMO or eCPR received early albumin administration (25 g/L) to prime the VA ECMO system. These patients were compared to patients who received a regimen based solely on balanced crystalloids (crystalloid group) or a regimen based on a 1:4 volume mixture of albumin (10 g/L) and balanced crystalloids (albumin group).

RESULTS

660 VA ECMO patients (66.4% eCPR) treated between January 2017 and June 2021 were analyzed, whereby 265 patients received crystalloid fluid therapy, 269 patients received albumin therapy, and 126 patients received early albumin therapy. When compared to the albumin and crystalloid groups, patients in the early albumin treatment group had significantly lower cumulative fluid balances (p < 0.05). However, this effect was only observed in the group of eCPR patients and not in patients with cardiogenic shock. Logistic regression revealed albumin administration as an independent predictor of increased survival (Odds ratio 1.66 (1.11-2.47) [95%-CI], p = 0.013). Yet, only eCPR patients showed a survival benefit from albumin administration compared to the crystalloid group (survival of 29.4% vs. 18.8%, p = 0.024).

CONCLUSION

Early albumin administration in eCPR patients was linked to a significant decline in fluid balance. Moreover, volume therapy with albumin application was an independent predictor for improved survival in eCPR patients.

Optimizing brain protection after cardiac arrest: advanced strategies and best practices

Cardiac arrest (CA) is associated with high incidence and mortality rates. Among patients who survive the acute phase, brain injury stands out as a primary cause of death or disability. Effective intensive care management, including targeted temperature management, seizure treatment and maintenance of normal physiological parameters, plays a crucial role in improving survival and neurological outcomes. Current guidelines advocate for neuroprotective strategies to mitigate secondary brain injury following CA, although certain treatments remain subjects of debate. Clinical examination and neuroimaging studies, both invasive and non-invasive neuromonitoring methods and serum biomarkers are valuable tools for predicting outcomes in comatose resuscitated patients. Neuromonitoring, in particular, provides vital insights for identifying complications, personalizing treatment approaches and forecasting prognosis in patients with brain injury post-CA. In this review, we offer an overview of advanced strategies and best practices aimed at optimizing brain protection after CA.

A national survey of medication utilization for cardiac resuscitation in the emergency department: A survey of emergency medicine pharmacists

PURPOSE

Vasoactive medications are used during advanced cardiac life support (ACLS) to shunt oxygenated blood to vital organs and after return of spontaneous circulation (ROSC) to maintain hemodynamic goals. However, limited evidence exists to support vasoactive medication recommendations in such scenarios, and it is unknown how practices vary among emergency departments across the US.

METHODS

A survey questionnaire (15 questions) was electronically distributed to emergency medicine pharmacists (EMPs) in the US through various professional listservs. Demographic information, American Heart Association ACLS algorithm medication use, and use of continuous vasopressor infusions and adjunct medications following ROSC were assessed and are reported descriptively.

RESULTS

The survey was distributed to 764 EMPs, with a 23% response rate from a wide geographic distribution and 48% of respondents practicing in academic medical centers. Epinephrine dosing and administration during cardiac arrest were reported by most to be in accordance with ACLS cardiac arrest algorithms. Calcium, magnesium sulfate, and sodium bicarbonate were the most common adjunct intravenous medications given during cardiac arrest. Norepinephrine was the first-choice vasopressor (81%) for post-ROSC hypotension, while epinephrine was preferred less frequently (17%). Antibiotics and sodium bicarbonate were the most frequently administered post-ROSC adjunct medications.

CONCLUSION

This survey of a geographically diverse group of EMPs demonstrated high ACLS algorithm adherence for epinephrine during cardiac arrest with frequent additional administration of nonalgorithm medications. Sodium bicarbonate and calcium were the most frequently administered adjunct medications during cardiac arrest, while sodium bicarbonate and antibiotics were the most frequently used adjunct medications following ROSC. Norepinephrine was the most commonly used vasopressor following ROSC.

Monocyte programmed death-ligand 1 upregulation in early post-out-of-hospital cardiac arrest is associated with increased risk of acute respiratory distress syndrome

Background

Out-of-hospital cardiac arrest (OHCA) is a major public health problem. Acute respiratory distress syndrome (ARDS) is a common condition in OHCA patients. We investigated the relationship between the expression of programmed death-1 (PD-1) related molecules and the development and prognosis of ARDS.

Methods

Between January 2021 and December 2023, post-resuscitated patients were screened for eligibility in the study. PD-1 related molecules expression was measured by flow cytometry at 48 h of admission in patients with OHCA. The prognostic variables were the development of ARDS during hospitalization and the 28-day patient mortality rate. We analyzed the relationship between the expression of PD-1-related molecules and the development of secondary ARDS in OHCA patients, and assessed the correlation of this expression with the prognosis of ARDS patients.

Results

In total, 107 consecutive OHCA patients were enrolled in this study. The median age of the enrolled patients was 60 years, with an age range of 53 to 67 years, and 71 % were male. Among the cardiac arrest patients, 44.8 % had a cardiac etiology, 30.8 % were witnessed, 17.8 % received bystander CPR, and 66.4 % had an initial rhythm of asystole. Our results showed that only monocyte ligand programmed death ligand-1 (PD-L1) expression was significantly elevated in the ARDS group of OHCA patients (P < 0.001). Among patients with ARDS, the expression of PD-L1 on monocytes in non-survivors was significantly higher than in survivors (P < 0.05). The Receiver operating characteristic curves analysis demonstrates that monocyte PD-L1 expression has predictive potential for the development and prognosis of ARDS. Multivariate logistic regression analysis showed that monocyte PD-L1 expression was an independent predictor of mortality in OHCA patients with ARDS.

Conclusions

This study indicates that patients with increased PD-L1 on monocytes after OHCA may be more likely to develop ARDS. The expression of PD-L1 on monocytes was an independent predictive factor for the incidence of ARDS and mortality rate in OHCA patients.

Cardiac arrest and microcirculatory dysfunction: a narrative review

PURPOSE OF REVIEW

This review provides an overview of the role of microcirculation in cardiac arrest and postcardiac arrest syndrome through handheld intravital microscopy and biomarkers. It highlights the importance of microcirculatory dysfunction in postcardiac arrest outcomes and explores potential therapeutic targets.

RECENT FINDINGS

Sublingual microcirculation is impaired in the early stage of postarrest and is potentially associated with increased mortality. Recent work suggests that the proportion of perfused small vessels is predictive of mortality. Microcirculatory impairment is consistently found to be independent of macrohemodynamic parameters. Biomarkers of endothelial cell injury and endothelial glycocalyx degradation are elevated in postarrest settings and may predict mortality and clinical outcomes, warranting further studies. Recent studies of exploratory therapies targeting microcirculation have shown some promise in animal models but still require significant research.

SUMMARY

Although research continues to suggest the important role that microcirculation may play in postcardiac arrest syndrome and cardiac arrest outcomes, the existing studies are still limited to draw any definitive conclusions. Further research is needed to better understand microcirculatory changes and their significance to improve cardiac arrest care and outcomes.

Cardiogenic shock severity predicts bleeding events in patients with temporary mechanical circulatory support

BACKGROUND

Data on shock severity and bleeding events in patients with temporary mechanical circulatory support (tMCS) are limited. We investigated the relationship between the Society for Cardiovascular Angiography and Interventions (SCAI) shock stage classification and bleeding events in patients with tMCS.

METHODS

We evaluated the data of 285 consecutive patients with tMCS who were admitted to our institution between June 2019 and May 2022. At the time of tMCS initiation, 81 patients (28.4%) were in SCAI stage A, 38 (13.3%) in stage B, 69 (24.2%) in stage C, 33 (11.6%) in stage D, and 64 (22.5%) in stage E. Multivariable logistic regression modeling was used to assess the association between the SCAI shock stage and in-hospital bleeding events.

RESULTS

In-hospital bleeding occurred in 100 patients (35.1%). The bleeding event rate increased incrementally across the SCAI shock stages (stage A, 11.1%; stage B, 15.8%; stage C, 37.7%; stage D, 54.6%; stage E, 64.1%). In-hospital bleeding was associated with the SCAI shock stage (p < 0.001). Compared with stage A, the adjusted odds ratios for in-hospital bleeding were 1.48 (95% confidence interval [CI] 0.47-4.66), 6.47 (95% CI 2.61-10.66), 11.59 (95% CI 3.77-35.64), and 7.85 (95% CI 2.51-24.55) for stages B, C, D, and E, respectively.

CONCLUSIONS

The SCAI shock stage predicted subsequent bleeding events in patients with tMCS. This simple scheme may be useful for tailored risk-based clinical assessment and management of patients with tMCS.

Invasive metastatic tumor-camouflaged ROS responsive nanosystem for targeting therapeutic brain injury after cardiac arrest

Drug transmission through the blood-brain barrier (BBB) is considered an arduous challenge for brain injury treatment following the return of spontaneous circulation after cardiac arrest (CA-ROSC). Inspired by the propensity of melanoma metastasis to the brain, B16F10 cell membranes are camouflaged on 2-methoxyestradiol (2ME2)-loaded reactive oxygen species (ROS)-triggered "Padlock" nanoparticles that are constructed by phenylboronic acid pinacol esters conjugated D-a-tocopheryl polyethylene glycol succinate (TPGS-PBAP). The biomimetic nanoparticles (BM@TP/2ME2) can be internalized, mainly mediated by the mutual recognition and interaction between CD44v6 expressed on B16F10 cell membranes and hyaluronic acid on cerebral vascular endothelial cells, and they responsively release 2ME2 by the oxidative stress microenvironment. Notably, BM@TP/2ME2 can scavenge excessive ROS to reestablish redox balance, reverse neuroinflammation, and restore autophagic flux in damaged neurons, eventually exerting a remarkable neuroprotective effect after CA-ROSC in vitro and in vivo. This biomimetic drug delivery system is a novel and promising strategy for the treatment of cerebral ischemia-reperfusion injury after CA-ROSC.

Post-resuscitation care in the NICU

Post-cardiac arrest syndrome is a unique pathophysiologic condition that is well-described in adult and pediatric populations. Early, goal-directed care after cardiac arrest can mitigate ongoing injury, improve clinical outcomes, and prevent re-arrest. There is a paucity of evidence about post-cardiac arrest care in the NICU, however, pediatric principles and guidelines can be applied in the NICU in the appropriate clinical context.

Feasibility and Safety of Targeted Temperature Management During Interhospital Transport of Post-Cardiac Arrest Patients

OBJECTIVES

Early initiation of targeted temperature management (TTM) is crucial for post-resuscitation care. Although TTM is initiated prior to transport and continued during interhospital transport (IHT), its feasibility and safety during IHT for cardiac arrest patients have not been thoroughly assessed. This study aims to evaluate the feasibility and safety of interhospital TTM for post-resuscitation patients.

METHODS

A retrospective analysis of post-cardiac arrest patients transported by a dedicated critical care transport team between January 2016 and April 2023 was conducted. Adult patients resuscitated from cardiac arrest without mental recovery were enrolled. The study population was divided into those who received TTM during IHT (IHT-TTM group) and those who did not (non-IHT-TTM group). The primary outcome was body temperature drop during transport, with hypotension, or desaturation during transport considered as secondary outcomes. Multivariable conditional logistic regression analysis was performed after frequency matching.

RESULTS

Among 593 post-cardiac arrest patients, 332 were included in the analysis after exclusions. Of these, 44 (13.3%) received TTM during IHT. Conditional logistic regression analysis showed significantly higher likelihood for a drop in body temperature during IHT for the IHT-TTM group, with an odds ratio (OR) of 12.91 (95%CI: 5.28-31.53). No significant association was found for hypotension (OR (95%CI): 0.72 (0.13-3.97)), or desaturation during IHT (0.65 (0.15-2.82)).

CONCLUSIONS

Administration of TTM during IHT for post-cardiac arrest patients appears to be feasible and safe. These findings support the implementation of dedicated critical care transport systems capable of providing TTM during IHT for post-cardiac arrest patients.

Ferritin Levels on Hospital Admission Predict Hypoxic-Ischemic Encephalopathy in Patients After Out-of-Hospital Cardiac Arrest: A Prospective Observational Single-Center Study

AIM

Out-of-hospital cardiac arrest (OHCA) is a major health concern in Western societies. Poor outcome after OHCA is determined by the extent of hypoxic-ischemic encephalopathy (HIE). Dysregulation of iron metabolism has prognostic relevance in patients with ischemic stroke and sepsis. The aim of this study was to determine whether serum iron parameters help to estimate outcomes after OHCA.

METHODS

In this prospective single-center study, 70 adult OHCA patients were analyzed. Serum ferritin, iron, transferrin (TRF), and TRF saturation (TRFS) were measured in blood samples drawn on day 0 (admission), day 2, day 4, and 6 months after the return of spontaneous circulation (ROSC). The association of 4 iron parameters with in-hospital mortality, neurological outcome (cerebral performance category [CPC]), and HIE was investigated by receiver operating characteristics and multivariate regression analyses.

RESULTS

OHCA subjects displayed significantly increased serum ferritin levels on day 0 and lowered iron, TRF, and TRFS on days 2 and 4 after ROSC, as compared to concentrations measured at a 6-month follow-up. Iron parameters were not associated with in-hospital mortality or neurological outcomes according to the CPC. Ferritin on admission was an independent predictor of features of HIE on cranial computed tomography and death due to HIE.

CONCLUSION

OHCA is associated with alterations in iron metabolism that persist for several days after ROSC. Ferritin on admission can help to predict HIE.

Liver protects neuron viability and electrocortical activity in post-cardiac arrest brain injury

Brain injury is the leading cause of mortality among patients who survive cardiac arrest (CA). Clinical studies have shown that the presence of post-CA hypoxic hepatitis or pre-CA liver disease is associated with increased mortality and inferior neurological recovery. In our in vivo global cerebral ischemia model, we observed a larger infarct area, elevated tissue injury scores, and increased intravascular CD45+ cell adhesion in reperfused brains with simultaneous hepatic ischemia than in those without it. In the ex vivo brain normothermic machine perfusion (NMP) model, we demonstrated that addition of a functioning liver to the brain NMP circuit significantly reduced post-CA brain injury, increased neuronal viability, and improved electrocortical activity. Furthermore, significant alterations were observed in both the transcriptome and metabolome in the presence or absence of hepatic ischemia. Our study highlights the crucial role of the liver in the pathogenesis of post-CA brain injury.

Intensive care unit cardiac arrest among very elderly critically ill patients - is cardiopulmonary resuscitation justified?

INTRODUCTION

The proportion of very elderly patients in the intensive care unit (ICU) is expected to rise. Furthermore, patients are likely more prone to suffer a cardiac arrest (CA) event within the ICU. The occurrence of intensive care unit cardiac arrest (ICU-CA) is associated with high mortality. To date, the incidence of ICU-CA and its clinical impact on outcome in the very old (≥ 90 years) patients treated is unknown.

METHODS

Retrospective analysis of all consecutive critically ill patients ≥ 90 years admitted to the ICU of a tertiary care university hospital in Hamburg (Germany). All patients suffering ICU-CA were included and CA characteristics and functional outcome was assessed. Clinical course and outcome were assessed and compared between the subgroups of patients with and without ICU-CA.

RESULTS

1,108 critically ill patients aged ≥ 90 years were admitted during the study period. The median age was 92.3 (91.0-94.2) years and 67% (n = 747) were female. 2% (n = 25) of this cohort suffered ICU-CA after a median duration 0.5 (0.2-3.2) days of ICU admission. The presumed cause of ICU-CA was cardiac in 64% (n = 16). The median resuscitation time was 10 (2-15) minutes and the initial rhythm was shockable in 20% (n = 5). Return of spontaneous circulation (ROSC) could be achieved in 68% (n = 17). The cause of ICU admission was primarily medical in the total cohort (ICU-CA: 48% vs. No ICU-CA: 34%, p = 0.13), surgical - planned (ICU-CA: 32% vs. No ICU-CA: 37%, p = 0.61) and surgical - unplanned/emergency (ICU-CA: 43% vs. No ICU-CA: 28%, p = 0.34). The median Charlson Comorbidity Index (CCI) was 2 (1-3) points for patients with ICU-CA and 1 (0-2) for patients without ICU-CA (p = 0.54). Patients with ICU-CA had a higher disease severity according to SAPS II (ICU-CA: 54 vs. No ICU-CA: 36 points, p < 0.001). Patients with ICU-CA had a higher rate of mechanically ventilation (ICU-CA: 64% vs. No ICU-CA: 34%, p < 0.01) and required vasopressor therapy more often (ICU-CA: 88% vs. No ICU-CA: 41%, p < 0.001). The ICU and in-hospital mortality was 88% (n = 22) and 100% (n = 25) in patients with ICU-CA compared to 17% (n = 179) and 28% (n = 306) in patients without ICU-CA. The mortality rate for patients with ICU-CA was observed to be 88% (n = 22) in the ICU and 100% (n = 25) in-hospital. In contrast, patients without ICU-CA had an in-ICU mortality rate of 17% (n = 179) and an in-hospital mortality rate of 28% (n = 306) (both p < 0.001).

CONCLUSION

The occurrence of ICU-CA in very elderly patients is rare but associated with high mortality. Providing CPR in this cohort did not lead to long-term survival at our centre. Very elderly patients admitted to the ICU likely benefit from supportive care only and should probably not be resuscitated due to poor chance of survival and ethical considerations. Providing personalized assurances that care will remain appropriate and in accordance with the patient's and family's wishes can optimise compassionate care while avoiding futile life-sustaining interventions.

Epinephrine, Pregabalin, and Crizotinib as Three Medicines with Polish Implications over Three Last Centuries and in View of Three Different Drug Discovery Approaches

The discovery of epinephrine (adrenaline) and its subsequent implications in medicine owes significant contributions to Cybulski across different centuries, who, in 1894, was pivotal in identifying the adrenal medulla's role in blood pressure regulation and naming the active substance "nadnerczyna", known today as adrenaline. His work demonstrated the adrenal glands' critical function in the body's regulatory mechanisms beyond the nervous system. Cybulski's groundbreaking research laid foundational knowledge for future endocrinological studies and pharmaceutical advancements. In the late 20th century, Andruszkiewicz collaborated with Silverman at Northwestern University to develop pregabalin, the active ingredient in Lyrica. Their innovative synthesis of gamma-aminobutyric acid derivatives led to a significant advancement in treating epilepsy, neuropathic pain, and fibromyalgia. Andruszkiewicz's expertise in organic chemistry and enzymology was crucial in this collaborative effort, resulting in the successful development and commercialization of Lyrica. Additionally, Mroczkowski's leadership at Pfizer contributed to the development of crizotinib, a notable anaplastic lymphoma kinase and proto-oncogene 1 tyrosine-protein kinase inhibitor used to treat specific types of non-small cell lung cancer. Her work exemplifies the continuing influence of Polish researchers in pioneering drug discovery and advancing therapeutic treatments over the past three centuries. These contributions highlight Poland's significant role in global pharmaceutical innovations and medical research.

Acute lung injury and post-cardiac arrest syndrome: a narrative review

BACKGROUND

Post-cardiac arrest syndrome (PCAS) presents a multifaceted challenge in clinical practice, characterized by severe neurological injury and high mortality rates despite advancements in management strategies. One of the important critical aspects of PCAS is post-arrest lung injury (PALI), which significantly contributes to poor outcomes. PALI arises from a complex interplay of pathophysiological mechanisms, including trauma from chest compressions, pulmonary ischemia-reperfusion (IR) injury, aspiration, and systemic inflammation. Despite its clinical significance, the pathophysiology of PALI remains incompletely understood, necessitating further investigation to optimize therapeutic approaches.

METHODS

This review comprehensively examines the existing literature to elucidate the epidemiology, pathophysiology, and therapeutic strategies for PALI. A comprehensive literature search was conducted to identify preclinical and clinical studies investigating PALI. Data from these studies were synthesized to provide a comprehensive overview of PALI and its management.

RESULTS

Epidemiological studies have highlighted the substantial prevalence of PALI in post-cardiac arrest patients, with up to 50% of survivors experiencing acute lung injury. Diagnostic imaging modalities, including chest X-rays, computed tomography, and lung ultrasound, play a crucial role in identifying PALI and assessing its severity. Pathophysiologically, PALI encompasses a spectrum of factors, including chest compression-related trauma, pulmonary IR injury, aspiration, and systemic inflammation, which collectively contribute to lung dysfunction and poor outcomes. Therapeutically, lung-protective ventilation strategies, such as low tidal volume ventilation and optimization of positive end-expiratory pressure, have emerged as cornerstone approaches in the management of PALI. Additionally, therapeutic hypothermia and emerging therapies targeting mitochondrial dysfunction hold promise in mitigating PALI-related morbidity and mortality.

CONCLUSION

PALI represents a significant clinical challenge in post-cardiac arrest care, necessitating prompt diagnosis and targeted interventions to improve outcomes. Mitochondrial-related therapies are among the novel therapeutic strategies for PALI. Further clinical research is warranted to optimize PALI management and enhance post-cardiac arrest care paradigms.

Mild (34 °C) versus moderate hypothermia (24 °C) in a swine model of extracorporeal cardiopulmonary resuscitation

Background

The role of hypothermia in post-arrest neuroprotection is controversial. Animal studies suggest potential benefits with lower temperatures, but high-fidelity ECPR models evaluating temperatures below 30 °C are lacking.

Objectives

To determine whether rapid cooling to 24 °C initiated upon reperfusion reduces brain injury compared to 34 °C in a swine model of ECPR.

Methods

Twenty-four female pigs had electrically induced VF and mechanical CPR for 30 min. Animals were cannulated for VA-ECMO and cooled to either 34 °C for 4 h (n = 8), 24 °C for 1 h with rewarming to 34 °C over 3 h (n = 7), or 24 °C for 4 h without rewarming (n = 9). Cooling was initiated upon VA-ECMO reperfusion by circulating ice water through the oxygenator. Brain temperature and cerebral and systemic hemodynamics were continuously monitored. After four hours on VA-ECMO, brain tissue was obtained for examination.

Results

Target brain temperature was achieved within 30 min of reperfusion (p = 0.74). Carotid blood flow was higher in the 24 °C without rewarming group throughout the VA-ECMO period compared to 34 °C and 24 °C with rewarming (p < 0.001). Vasopressin requirement was higher in animals treated with 24 °C without rewarming (p = 0.07). Compared to 34 °C, animals treated with 24 °C with rewarming were less coagulopathic and had less immunohistochemistry-detected neurologic injury. There were no differences in global brain injury score.

Conclusions

Despite improvement in carotid blood flow and immunohistochemistry detected neurologic injury, reperfusion at 24 °C with or without rewarming did not reduce early global brain injury compared to 34 °C in a swine model of ECPR.

Neurological prognosis prediction for cardiac arrest patients using quantitative imaging biomarkers from brain computed tomography

PURPOSE

We aimed to predict the neurological prognosis of cardiac arrest (CA) patients using quantitative imaging biomarkers extracted from brain computed tomography images.

METHODS

We retrospectively enrolled 86 CA patients (good prognosis, 32; poor prognosis, 54) who were treated at three hospitals between 2017 and 2019. We then extracted 1131 quantitative imaging biomarkers from whole-brain and local volumes of interest in the computed tomography images of the patients. The data were split into training and test sets containing 60 and 26 samples, respectively, and the training set was used to select representative quantitative imaging biomarkers for classification. In univariate analysis, the classification was evaluated using the p-value of the Brunner-Munzel test and area under the receiver operating characteristic curve (AUC) for the test set. In multivariate analysis, machine learning models reflecting nonlinear and complex relations were trained, and they were evaluated using the AUC on the test set.

RESULTS

The best performance provided p = 0.009 (<0.01) and an AUC of 0.775 (95% confidence interval, 0.590-0.960) for the univariate analysis and an AUCof0.813 (95% confidence interval, 0.640-0.985) for the multivariate analysis. Overall, the gray level with the maximum gradient in the histogram of the three-dimensionally low-pass-filtered image was an important feature for prediction across the analyses.

CONCLUSIONS

Quantitative imaging biomarkers can be used in neurological prognosis prediction for CA patients. Relevant biomarkers may contribute to protocolized computed tomography image acquisition to ensure proper decision support in acute care.

Extracerebral multiple organ dysfunction and interactions with brain injury after cardiac arrest

Cardiac arrest and successful resuscitation cause whole-body ischemia and reperfusion, leading to brain injury and extracerebral multiple organ dysfunction. Brain injury is the leading cause of death and long-term disability in resuscitated survivors, and was conceptualized and treated as an isolated injury, which has neglected the brain-visceral organ crosstalk. Extracerebral organ dysfunction is common and is significantly associated with mortality and poor neurological prognosis after resuscitation. However, detailed description of the characteristics of post-resuscitation multiple organ dysfunction is lacking, and the bidirectional interactions between brain and visceral organs need to be elucidated to explore new treatment for neuroprotection. This review aims to describe current concepts of post-cardiac arrest brain injury and specific characteristics of post-resuscitation dysfunction in cardiovascular, respiratory, renal, hepatic, adrenal, gastrointestinal, and neurohumoral systems. Additionally, we discuss the crosstalk between brain and extracerebral organs, especially focusing on how visceral organ dysfunction and other factors affect brain injury progression. We think that clarifying these interactions is of profound significance on how we treat patients for neural/systemic protection to improve outcome.

Inflammatory response after prehospital high-dose glucocorticoid to patients resuscitated from out-of-hospital cardiac arrest: A sub-study of the STEROHCA trial

BACKGROUND

The post-cardiac arrest syndrome (PCAS) after out-of-hospital cardiac arrest (OHCA) is characterized by a series of pathological events, including inflammation. In the randomized "STERoid for OHCA" (STEROHCA) trial, prehospital high-dose glucocorticoid decreased interleukin (IL) 6 and C-reactive protein levels following resuscitated OHCA. The aim of this predefined sub-study was to assess the inflammatory response the first three days of admission.

METHODS

The STEROHCA trial enrolled 137 OHCA patients randomized to either a single prehospital injection of methylprednisolone 250 mg or placebo. Inflammatory markers, including pro- and anti-inflammatory cytokines, were analyzed in plasma samples, from 0-, 24-, 48-, and 72 h post-admission. Mixed-model analyses were applied using log-transformed data to assess group differences.

RESULTS

The 137 patients included in this sub-study had a median age of 67 years (57 to 74), and the 180-day survival rates were 75% (n = 51/68) and 64% (n = 44/69) in the glucocorticoid and placebo group, respectively. A total of 130 (95%) patients had at least one plasma sample available. The anti-inflammatory cytokine IL-10 was increased at hospital admission in the glucocorticoid group (ratio 2.74 (1.49-5.05), p = 0.006), but the intervention showed the strongest effect after 24 h, decreasing pro-inflammatory levels of IL-6 (ratio 0.06 (0.03-0.10), p < 0.001), IL-8 (ratio 0.53 (0.38-0.75), p < 0.001), macrophage chemokine protein-1 (MCP-1, ratio 0.02 (0.13-0.31), p < 0.001), macrophage inflammatory protein-1-beta (MIP-1b, ratio 0.28 (0.18-0.45), p < 0.001), and tumor necrosis factor-α (TNF-α, ratio 0.6 (0.4-0.8), p = 0.01).

CONCLUSION

Administering high-dose glucocorticoid treatment promptly after resuscitation from OHCA influenced the inflammatory response with a reduction in several systemic proinflammatory cytokines after 24 h.

TRIAL REGISTRATION

EudraCT number: 2020-000855-11; submitted March 30, 2020. URL: https://www.

CLINICALTRIALS

gov; Unique Identifier: NCT04624776.

The impact of pediatric post-cardiac arrest care on survival: A multicenter review from the AHA get with the Guidelines®-resuscitation post-cardiac arrest care registry

AIM

Adherence to post-cardiac arrest care (PCAC) recommendations is associated with improved outcomes for adults. We aimed to describe the survival impact of meeting American Heart Association (AHA) PCAC guidelines in children after cardiac arrest.

METHODS

We conducted a retrospective study using Get With The Guidelines® Resuscitation's (GWTG®-R) registry to describe the PCAC of patients ≤ 18 years old who suffered an in-hospital or out-of-hospital cardiac arrest (IHCA or OHCA). We evaluated the association between the absence of hypotension and fever in the initial 24 h following return of circulation (ROC) with survival to hospital discharge. We reviewed the utilization of monitoring/evaluation tools recommended in pediatric PCAC guidelines: electrocardiogram (ECG), electroencephalogram (EEG), and neuro-imaging.

RESULTS

We found 385 pediatric patients who suffered an IHCA or OHCA from 2015 through 2019 and survived at least 6 h post-ROC. Sixty-six percent of patients survived to hospital discharge. Following ROC, 56% of patients had EEG monitoring, 80% had an ECG performed, 47% had a head CT, and 26% had a cerebral MRI. In the initial 24 h post-ROC, 92% of patients did not have hypotension and 79% were afebrile. Patients without hypotension in the initial 24 h post-ROC had higher odds of survival to hospital discharge than those with hypotension (aOR 4.96; 95% CI 2.07, 11.90; p = 0.0003), adjusting for age and cardiac arrest location. Patients without hypotension and without fever in the initial 24 h post-ROC had higher odds of survival to hospital discharge compared to patients who had either hypotension or fever or both (aOR 1.98; 95% CI 1.06,3.71; p = 0.034).

CONCLUSION

In this retrospective multicenter registry study, absence of both post-cardiac arrest hypotension and fever were associated with increased odds of survival to hospital discharge. Further research is needed to understand the full impact of PCAC recommendation compliance on survival outcomes.

Validation of the NULL-EASE Score for Predicting Survival in a Multiethnic Asian Cohort of Out-of-Hospital Cardiac Arrest

BACKGROUND

NULL-PLEASE is a simple and accurate clinical scoring system developed in a Western cohort of patients with out-of-hospital cardiac arrest (OHCA). The need for blood test results limits its use in early stages of care. We adapted and validated the NULL-EASE score (without laboratory tests) in an independent, multiethnic Asian cohort of patients with out-of-hospital cardiac arrest.

METHODS AND RESULTS

Using the Singapore OHCA registry, we included consecutive adult patients with out-of-hospital cardiac arrest who survived to hospital admission between April 2010 to December 2020. In-hospital mortality was the primary outcome. Logistic regression analyses were performed with STATA MP v18. Of 3274 patients (median age 64, interquartile range 54-75; 67.9% male) included in the study, 2476 (75.6%) had in-hospital mortality. NULL-EASE score was significantly lower in survivors compared with nonsurvivors (median [inter quartile range] 3 [1-4] versus 6 [4-7]; P<0.001) and strongly predictive of mortality (area under receiver operating characteristic, 0.81 [95% CI, 0.79-0.83]). Patients with a score of ≥3 had higher odds of mortality (adjusted odds ratio, 8.11 [95% CI, 6.57-10.00]) when compared with those with lower scores, after adjusting for sex, residential arrest, diabetes, respiratory disease, and stroke. A cutoff value of ≥3 predicted mortality with 92.2% sensitivity, 84.1% positive predictive value, 46.1% specificity, and 65.5% negative predictive value. NULL-EASE score performed better in younger compared with older patients (area under receiver operating characteristic, 0.82 versus 0.77, P=0.008).

CONCLUSIONS

The NULL-EASE score has good discriminative performance (sensitivity and accuracy) in our multiethnic Asian cohort, but the cutoff of ≥3 falls short of the desired level of specificity for therapeutic decision-making.

Emergent coronary revascularization with percutaneous coronary intervention and coronary artery bypass grafting in patients receiving extracorporeal cardiopulmonary resuscitation

OBJECTIVES

Extracorporeal cardiopulmonary resuscitation (ECPR) has emerged as a rescue for refractory cardiac arrest, of which acute coronary syndrome is a common cause. Data on the coronary revascularization strategy in patients receiving ECPR remain limited.

METHODS

The ECPR databases from two referral hospitals were screened for patients who underwent emergent revascularization. The baseline characteristics were matched 1:1 using propensity score between patients who underwent coronary artery bypass grafting (CABG) and those who received percutaneous coronary intervention (PCI). Outcomes, including success rate of weaning from extracorporeal membrane oxygenation (ECMO), hospital survival, and midterm survival in hospital survivors, were compared between CABG and PCI.

RESULTS

After matching, most of the patients (95%) had triple vessel disease. Compared with PCI (n = 40), emergent CABG (n = 40) had better early outcomes, in terms of the rates of successful ECMO weaning (71.1% vs 48.7%, P = 0.05) and hospital survival (56.4% versus 32.4%, P = 0.04). After a mean follow-up of 2 years, both revascularization strategies were associated with favourable midterm survival among hospital survivors (75.3% after CABG vs 88.9% after PCI, P = 0.49), with a trend towards fewer reinterventions in patients who underwent CABG (P = 0.07).

CONCLUSIONS

In patients who received ECPR because of triple vessel disease, the hospital outcomes were better after emergent CABG than after PCI. More evidence is required to determine the optimal revascularization strategy for patients who receive ECPR.

ECPR-the evolving role in cardiac arrest

Extracorporeal cardiopulmonary resuscitation (ECPR) describes the use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) to restore blood circulation in patients during refractory cardiac arrest. So far, ECPR is not the standard of care but has become part of clinical routine for select patients in many places. As ECPR is a highly invasive support option associated with considerable risks for fatal complications, premature use in patients who may have return of spontaneous circulation should be avoided. However, the selection criteria for ECPR are still evolving, as the search for evidence is ongoing. Recent randomized controlled trials of different ECPR strategies support its use within integrated systems built around highly specialized ECPR centers. The ECPR caseload is an important predictor of patient survival, and continuous training is key for evidence-based quality of care. Typical complications after ECPR include vascular injury or malposition of cannulas, thrombotic complications, hemolysis, and bleeding events that require early detection and interdisciplinary management. When provided by highly specialized and well-trained expert teams in dedicated ECPR centers within integrated pre-hospital and intra-hospital emergency care systems, ECPR may improve survival in select patients with refractory cardiac arrest. This article is freely available.

Selective brain perfusion improves the neurological outcomes after extracorporeal cardiopulmonary resuscitation in a rat model

BACKGROUND

The major concern in patients who have suffered from cardiac arrest (CA) and undergone successful extracorporeal cardiopulmonary resuscitation (E-CPR) is poor neurological outcomes. In this study, we aimed to introduce a rat model of selective brain perfusion (SBP) during E-CPR to improve the neurological outcome after CA.

METHODS

The rats underwent 7 min of untreated asphyxial CA and then were resuscitated with E-CPR for 30 min. The right external jugular vein and right femoral artery were separately cannulated to the E-CPR outflow and inflow. The right common carotid artery was cannulated from the proximal to the distal side for SBP. Subsequently, rats were removed from E-CPR, wounds were closed, and 90 min of intensive care were provided. Neurological deficit scores were tested after 4 h of recovery when the rats were mechanical ventilation-free. S100 calcium-binding protein B (S100B) and glial fibrillary acidic protein (GFAP) were detected through immunohistochemistry (IHC) of brain tissue.

RESULTS

The rats that received SBP while resuscitated by E-CPR showed markedly better neurological performances after 4-h recovery than those resuscitated by E-CPR only. The IHC staining of GFAP and S100B in the hippocampus was low in the rats receiving SBP during E-CPR, but only GFAP showed significant differences.

CONCLUSIONS

We successfully developed a novel and reproducible rat model of SBP while resuscitated by E-CPR to ameliorate the neurological performances after CA. This achievement might have opportunities for studying how to improve the neurological outcome in the clinical condition.

The role of serum/glucocorticoid-regulated kinase 1 in brain function following cerebral ischemia

Cardiopulmonary arrest (CA) is a major cause of death/disability in the U.S. with poor prognosis and survival rates. Current therapeutic challenges are physiologically complex because they involve hypoperfusion (decreased cerebral blood flow), neuroinflammation, and mitochondrial dysfunction. We previously discovered novel serum/glucocorticoid-regulated kinase 1 (SGK1) is highly expressed in brain of neurons that are susceptible to ischemia (hippocampus and cortex). We inhibited SGK1 and utilized pharmacological (specific inhibitor, GSK650394) and neuron-specific genetic approaches (shRNA) in rodent models of CA to determine if SGK1 is responsible for hypoperfusion, neuroinflammation, mitochondrial dysfunctional, and neurological deficits after CA. Inhibition of SGK1 alleviated cortical hypoperfusion and neuroinflammation (via Iba1, GFAP, and cytokine array). Treatment with GSK650394 enhanced mitochondrial function (via Seahorse respirometry) in the hippocampus 3 and 7 days after CA. Neuronal injury (via MAP2, dMBP, and Golgi staining) in the hippocampus and cortex was observed 7 days after CA but ameliorated with SGK1-shRNA. Moreover, SGK1 mediated neuronal injury by regulating the Ndrg1-SOX10 axis. Finally, animals subjected to CA exhibited learning/memory, motor, and anxiety deficits after CA, whereas SGK1 inhibition via SGK1-shRNA improved neurocognitive function. The present study suggests the fundamental roles of SGK1 in brain circulation and neuronal survival/death in cerebral ischemia-related diseases.

Multi-omics Study of Hypoxic-Ischemic Brain Injury After Cardiopulmonary Resuscitation in Swine

BACKGROUND

Hypoxic-ischemic brain injury is a common cause of mortality after cardiac arrest (CA) and cardiopulmonary resuscitation; however, the specific underlying mechanisms are unclear. This study aimed to explore postresuscitation changes based on multi-omics profiling.

METHODS

A CA swine model was established, and the neurological function was assessed at 24 h after resuscitation, followed by euthanizing animals. Their fecal, blood, and hippocampus samples were collected to analyze gut microbiota, metabolomics, and transcriptomics.

RESULTS

The 16S ribosomal DNA sequencing showed that the microbiota composition and diversity changed after resuscitation, in which the abundance of Akkermansia and Muribaculaceae_unclassified increased while the abundance of Bifidobacterium and Romboutsia decreased. A relationship was observed between CA-related microbes and metabolites via integrated analysis of gut microbiota and metabolomics, in which Escherichia-Shigella was positively correlated with glycine. Combined metabolomics and transcriptomics analysis showed that glycine was positively correlated with genes involved in apoptosis, interleukin-17, mitogen-activated protein kinases, nuclear factor kappa B, and Toll-like receptor signal pathways.

CONCLUSIONS

Our results provided novel insight into the mechanism of hypoxic-ischemic brain injury after resuscitation, which is envisaged to help identify potential diagnostic and therapeutic markers.

Effect of dimethyl fumarate on mitochondrial metabolism in a pediatric porcine model of asphyxia-induced in-hospital cardiac arrest

Neurological and cardiac injuries are significant contributors to morbidity and mortality following pediatric in-hospital cardiac arrest (IHCA). Preservation of mitochondrial function may be critical for reducing these injuries. Dimethyl fumarate (DMF) has shown potential to enhance mitochondrial content and reduce oxidative damage. To investigate the efficacy of DMF in mitigating mitochondrial injury in a pediatric porcine model of IHCA, toddler-aged piglets were subjected to asphyxia-induced CA, followed by ventricular fibrillation, high-quality cardiopulmonary resuscitation, and random assignment to receive either DMF (30 mg/kg) or placebo for four days. Sham animals underwent similar anesthesia protocols without CA. After four days, tissues were analyzed for mitochondrial markers. In the brain, untreated CA animals exhibited a reduced expression of proteins of the oxidative phosphorylation system (CI, CIV, CV) and decreased mitochondrial respiration (p < 0.001). Despite alterations in mitochondrial content and morphology in the myocardium, as assessed per transmission electron microscopy, mitochondrial function was unchanged. DMF treatment counteracted 25% of the proteomic changes induced by CA in the brain, and preserved mitochondrial structure in the myocardium. DMF demonstrates a potential therapeutic benefit in preserving mitochondrial integrity following asphyxia-induced IHCA. Further investigation is warranted to fully elucidate DMF's protective mechanisms and optimize its therapeutic application in post-arrest care.

Early Enteral Nutrition Could Be Associated with Improved Survival Outcome in Cardiac Arrest

Background

Although the latest European and US guidelines recommend that early enteral nutrition (EN) be attempted in critically ill patients, there is still a lack of research on feeding strategies for patients after cardiac arrest (CA). Due to the unique pathophysiology following CA, it remains unknown whether evidence from other diseases can be applied in this condition.

Objective

We aimed to explore the relationship between the timing of EN (within 48 hours or after 48 hours) and clinical outcomes and safety in CA.

Method

From the MIMIC-IV (version 2.2) database, we conducted this retrospective cohort study. A 1 : 1 propensity score matching (PSM) analysis was also conducted to prevent potential interference from confounders. Moreover, adjusted proportional hazards model regression models were used to adjust for prehospital and hospitalization characteristics to verify the independence of the association between early EN initiation and patient outcomes.

Results

Of the initial 1286 patients, 670 were equally assigned to the early EN or delayed EN group after PSM. Patients in the early EN group had improved survival outcomes than those in the delayed EN group within 30 days (HR = 0.779, 95% confidence interval [CI] [0.611-0.994], p = 0.041). Similar results were shown at 90 and 180 days. However, there was no significant difference in neurological outcome between the two groups at 30 days (51% vs. 57%, odds ratio [OR] = 0.786, 95% CI [0.580-1.066], p = 0.070). Patients who underwent early EN had a lower risk of ileus than patients who underwent delayed EN (4% vs. 8%, OR = 0.461, 95% CI [0.233-0.909], p = 0.016). Moreover, patients who underwent early EN had shorter hospital stays.

Conclusion

Early EN could be associated with improved survival outcomes for patients after CA. Further studies are needed to verify it. However, at present, we might consider early EN to be a more suitable feeding strategy for CA.

Leukocyte filtration and leukocyte modulation therapy during extracorporeal cardiopulmonary resuscitation in a porcine model of prolonged cardiac arrest

Extracorporeal cardiopulmonary resuscitation (ECPR) is emerging as a feasible and effective rescue strategy for prolonged cardiac arrest (CA). However, prolonged total body ischemia and reperfusion can cause microvascular occlusion that prevents organ reperfusion and recovery of function. One hypothesized mechanism of microvascular "no-reflow" is leukocyte adhesion and formation of neutrophil extracellular traps. In this study we tested the hypothesis that a leukocyte filter (LF) or leukocyte modulation device (L-MOD) could reduce NETosis and improve recovery of heart and brain function in a swine model of prolonged cardiac arrest treated with ECPR. Thirty-six swine (45.5 ± 2.5 kg, evenly distributed sex) underwent 8 min of untreated ventricular fibrillation CA followed by 30 min of mechanical CPR with subsequent 8 h of ECPR. Two females were later excluded from analysis due to CPR complications. Swine were randomized to standard care (Control group), LF, or L-MOD at the onset of CPR. NET formation was quantified by serum dsDNA and citrullinated histone as well as immunofluorescence staining of the heart and brain for citrullinated histone in the microvasculature. Primary outcomes included recovery of cardiac function based on cardiac resuscitability score (CRS) and recovery of neurologic function based on the somatosensory evoked potential (SSEP) N20 cortical response. In this model of prolonged CA treated with ECPR we observed significant increases in serum biomarkers of NETosis and immunohistochemical evidence of microvascular NET formation in the heart and brain that were not reduced by LF or L-MOD therapy. Correspondingly, there were no significant differences in CRS and SSEP recovery between Control, LF, and L-MOD groups 8 h after ECPR onset (CRS = 3.1 ± 2.7, 3.7 ± 2.6, and 2.6 ± 2.6 respectively; p = 0.606; and SSEP = 27.9 ± 13.0%, 36.7 ± 10.5%, and 31.2 ± 9.8% respectively, p = 0.194). In this model of prolonged CA treated with ECPR, the use of LF or L-MOD therapy during ECPR did not reduce microvascular NETosis or improve recovery of myocardial or brain function. The causal relationship between microvascular NETosis, no-reflow, and recovery of organ function after prolonged cardiac arrest treated with ECPR requires further investigation.

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.

COMBINATION OF HYPEROXYGENATION AND TARGETED TEMPERATURE MANAGEMENT IMPROVES FUNCTIONAL OUTCOMES OF POST CARDIAC ARREST SYNDROME IRRESPECTIVE OF CAUSES OF ARREST IN RATS

ABSTRACT

Background: The high mortality rates of patients who are resuscitated from cardiac arrest (CA) are attributed to post cardiac arrest syndrome (PCAS). This study evaluated the effect of hyperoxygenation and targeted temperature management (TTM) on PCAS in rats with different causes of CA. Methods and Results: One hundred sixty-eight Sprague-Dawley rats were equally divided into asphyxial and dysrhythmic groups. Animals were further randomized into four subgroups immediately after resuscitation: normoxia-normothermia (NO-NT), ventilated with 21% oxygen under normothermia; hyperoxia-normothermia (HO-NT), ventilated with 100% oxygen for 3 hours under normothermia; normoxia-hypothermia (NO-HT), ventilated with 21% oxygen for 3 hours under hypothermia; and hyperoxia-hypothermia (HO-HT), ventilated with 100% oxygen for 3 hours under hypothermia. Post resuscitation cardiac dysfunction, neurological recovery, and pathological analysis were assessed. For asphyxial CA, HO-NT and HO-HT (68.8% and 75.0%) had significantly higher survival than NO-NT and NO-HT (31.3% and 31.3%). For dysrhythmic CA, NO-HT and HO-HT (81.3% and 87.5%) had significantly higher survival than NO-NT and HO-NT (44.0% and 50.0%). When all of the rats were considered, the survival rate was much higher in HO-HT (81.3%). Compared with NO-NT (57.7% ± 14.9% and 40.3% ± 7.8%), the collagen volume fraction and the proportion of fluoro-jade B-positive area in HO-HT (14.0% ± 5.7% and 28.0% ± 13.3%) were significantly reduced. Conclusion: The beneficial effects of hyperoxygenation and TTM are dependent on the cause of arrest: hyperoxygenation benefits asphyxial, whereas TTM benefits dysrhythmic CA. The combination of hyperoxygenation and TTM could effectively improve the functional outcome of PCAS regardless of the cause of CA.

The Effect of Targeted Temperature Therapy on Antioxidant Levels in Patients With Spontaneous Circulation After Cardiac Arrest

Introduction In this study, we aimed to measure the change in total antioxidant status (TAS), total oxidant stress (TOS), oxidative stress index (OSI), and nuclear factor erythroid 2 (Nrf-2) levels during the treatment period in patients who restored spontaneous circulation return after cardiac arrest with targeted temperature management (TTM) therapy in our hospital. Methods The study included 36 patients who were hospitalized in the anesthesia intensive care unit and coronary intensive care unit of our hospital and were treated with TTM therapy after cardiac arrest. TAS, TOS, OSI, and Nrf-2 levels were measured at 0 (beginning), 12, 24, and 48 (end) hours of TTM therapy. Results The mean age of the patients participating in the study was 54.25±17.10. TAS and TOS levels decreased gradually during TTM therapy, but statistically significant decrease was observed at the end of the hour. When Nrf-2 and OSI levels were evaluated, it was found that no statistically significant difference was observed during the TTM therapy. Conclusion In our study, the oxidant-antioxidant balance was preserved in patients who received TTM therapy after cardiac arrest. We predict TTM therapy is effective on oxidative stress after cardiac arrest and should be applied for at least 48 hours.

The role of magnesium in cardiac arrest

Cardiac arrest is a leading cause of death globally. Only 25.8% of in-hospital and 33.5% of out-of-hospital individuals who achieve spontaneous circulation following cardiac arrest survive to leave the hospital. Respiratory failure and acute coronary syndrome are the two most common etiologies of cardiac arrest. Effort has been made to improve the outcomes of individuals resuscitated from cardiac arrest. Magnesium is an ion that is critical to the function of all cells and organs. It is often overlooked in everyday clinical practice. At present, there have only been a small number of reviews discussing the role of magnesium in cardiac arrest. In this review, for the first time, we provide a comprehensive overview of magnesium research in cardiac arrest focusing on the effects of magnesium on the occurrence and prognosis of cardiac arrest, as well as in the two main diseases causing cardiac arrest, respiratory failure and acute coronary syndrome. The current findings support the view that magnesium disorder is associated with increased risk of cardiac arrest as well as respiratory failure and acute coronary syndrome.

Neurological outcome following out of hospital cardiac arrest: Evaluation of performance of existing risk prediction models in a UK cohort

Introduction

Out of hospital cardiac arrest (OHCA) is a common problem. Rates of survival are low and a proportion of survivors are left with an unfavourable neurological outcome. Four models have been developed to predict risk of unfavourable outcome at the time of critical care admission - the Cardiac Arrest Hospital Prognosis (CAHP), MIRACLE2, Out of Hospital Cardiac Arrest (OHCA), and Targeted Temperature Management (TTM) models. This evaluation evaluates the performance of these four models in a United Kingdom population and provides comparison to performance of the Acute Physiology and Chronic Health Evaluation II (APACHE-II) score.

Methods

A retrospective evaluation of the performance of the models was conducted over a 43-month period in 414 adult, non-pregnant patients presenting consecutively following non-traumatic OHCA to the five units in our regional critical care network. Scores were generated for each model for where patients had complete data (CAHP = 347, MIRACLE2 = 375, OHCA = 356, TTM = 385). Cerebral Performance Category (CPC) outcome was calculated for each patient at last documented follow up and an unfavourable outcome defined as CPC ⩾ 3. Performance for discrimination of unfavourable outcome was tested by generating receiver operating characteristic (ROC) curves for each model and comparing the area under the curve (AUC).

Results

Best performance for discrimination of unfavourable outcome was demonstrated by the high risk group of the CAHP score with an AUC of 0.87 [95% CI 0.83-0.91], specificity of 97.1% [95% CI 93.8-100] and positive predictive value (PPV) of 96.3% [95% CI 92.2-100]. The high risk group of the MIRACLE2 model, which is significantly easier to calculate, had an AUC of 0.81 [95% CI 0.76-0.86], specificity of 92.3% [95% CI 87.2-97.4] and PPV of 95.2% [95% CI 91.9-98.4].

Conclusion

The CAHP, MIRACLE2, OHCA and TTM scores all perform comparably in a UK population to the original development and validation cohorts. All four scores outperform APACHE-II in a population of patients resuscitated from OHCA. CAHP and TTM perform best but are more complex to calculate than MIRACLE2, which displays inferior performance.

REMIMAZOLAM IMPROVES THE MARKERS OF POSTRESUSCITATION CEREBRAL INJURY IN A SWINE MODEL OF CARDIAC ARREST

ABSTRACT

Introduction: Previous studies have manifested that those sedatives acting on γ-aminobutyric acid A (GABAa) receptor could produce effective brain protection against regional and global ischemic stimulation. The present study was designed to investigate the effect of a novel GABAa receptor agonist, remimazolam postconditioning (RP) on cerebral outcome after global ischemic stimulation induced by cardiac arrest and resuscitation in swine. Methods: A total of 24 swine were used in this study, in which the animals were randomly divided into the following three groups: sham group (n = 6), cardiopulmonary resuscitation (CPR) group (n = 9), and CPR + RP group (n = 9). The experimental model was established by the procedure of 10 min of cardiac arrest and 5 min of CPR. Those resuscitated swine in the CPR + RP group received an intravenous infusion of 2.5 mg/kg of remimazolam within 60 min. Postresuscitation cerebral injury biomarkers and neurological function were evaluated for a total of 24 h. At 24 h after resuscitation, brain cortex was harvested to evaluate the severity of pathologic damage, including tissue inflammation, oxidative stress, apoptosis, and necroptosis. Results: Baseline characteristics and CPR outcomes were not significantly different between the CPR and CPR + RP groups. After resuscitation, significantly greater cerebral injury and neurological dysfunction were observed in the CPR and CPR + RP groups than in the sham group. However, remimazolam postconditioning significantly alleviated cerebral injury and improved neurological dysfunction after resuscitation when compared with the CPR group. At 24 h after resuscitation, tissue inflammation, oxidative stress, and cell apoptosis and necroptosis were significantly increased in the CPR and CPR + RP groups when compared with the sham group. Nevertheless, the severity of pathologic damage mentioned previously were significantly milder in those swine treated with the remimazolam when compared with the CPR group. Conclusions: In a swine model of cardiac arrest and resuscitation, the remimazolam administered after resuscitation significantly improved the markers of postresuscitation cerebral injury and therefore protected the brain against global ischemic stimulation.

Organ-Specific Mitochondrial Alterations Following Ischemia-Reperfusion Injury in Post-Cardiac Arrest Syndrome: A Comprehensive Review

BACKGROUND

Mitochondrial dysfunction, which is triggered by systemic ischemia-reperfusion (IR) injury and affects various organs, is a key factor in the development of post-cardiac arrest syndrome (PCAS). Current research on PCAS primarily addresses generalized mitochondrial responses, resulting in a knowledge gap regarding organ-specific mitochondrial dynamics. This review focuses on the organ-specific mitochondrial responses to IR injury, particularly examining the brain, heart, and kidneys, to highlight potential therapeutic strategies targeting mitochondrial dysfunction to enhance outcomes post-IR injury.

METHODS AND RESULTS

We conducted a narrative review examining recent advancements in mitochondrial research related to IR injury. Mitochondrial responses to IR injury exhibit considerable variation across different organ systems, influenced by unique mitochondrial structures, bioenergetics, and antioxidative capacities. Each organ demonstrates distinct mitochondrial behaviors that have evolved to fulfill specific metabolic and functional needs. For example, cerebral mitochondria display dynamic responses that can be both protective and detrimental to neuronal activity and function during ischemic events. Cardiac mitochondria show vulnerability to IR-induced oxidative stress, while renal mitochondria exhibit a unique pattern of fission and fusion, closely linked to their susceptibility to acute kidney injury. This organ-specific heterogeneity in mitochondrial responses requires the development of tailored interventions. Progress in mitochondrial medicine, especially in the realms of genomics and metabolomics, is paving the way for innovative strategies to combat mitochondrial dysfunction. Emerging techniques such as mitochondrial transplantation hold the potential to revolutionize the management of IR injury in resuscitation science.

CONCLUSIONS

The investigation into organ-specific mitochondrial responses to IR injury is pivotal in the realm of resuscitation research, particularly within the context of PCAS. This nuanced understanding holds the promise of revolutionizing PCAS management, addressing the unique mitochondrial dysfunctions observed in critical organs affected by IR injury.

The Evolving Role of Electroencephalography in Postarrest Care

Electroencephalography is an accessible, portable, noninvasive and safe means of evaluating a patient's brain activity. It can aid in diagnosis and management decisions for post-cardiac arrest patients with seizures, myoclonus and other non-epileptic movements. It also plays an important role in a multimodal approach to neuroprognostication predicting both poor and favorable outcomes. Individuals ordering, performing and interpreting these tests, regardless of the indication, should understand the supporting evidence, logistical considerations, limitations and impact the results may have on postarrest patients and their families as outlined herein.

The prognostic value of the phosphate-to-albumin ratio in patients with OHCA: A multicenter observational study

PURPOSE

In patients with out-of-hospital cardiac arrest (OHCA), early and accurate outcome prediction is crucial for making treatment decisions and informing their relatives. A previous study reported an association between high phosphate levels and unfavorable neurological outcomes after return of spontaneous circulation (ROSC); however, its prognostic value was insufficient when used independently. Therefore, this study aimed to validate the usefulness of the phosphate-to-albumin ratio (PAR) in predicting neurological outcomes and in-hospital mortality by incorporating albumin, another known prognostic indicator.

MATERIALS AND METHODS

This multicenter observational study included adult OHCA survivors from October 2015 to June 2021. The primary endpoint was an unfavorable neurological outcome at hospital discharge, defined as a cerebral performance category score of 3-5. The in-hospital mortality rates were also evaluated.

RESULTS

Of the 2397 adult OHCA survivors, PAR differed significantly between the unfavorable and favorable neurological outcome groups, as well as between the non-survival and survival to hospital discharge groups (2.4 vs 1.4, 2.5 vs 1.6, respectively). The area under the receiver operating characteristic curve (AUROC) value of the PAR for predicting unfavorable neurological outcome was 0.81 (95% confidence interval [CI], 0.79-0.83), and the AUROC value for predicting in-hospital mortality was 0.76 (95% CI, 0.74-0.78). In multivariable analysis, the PAR was independently associated with unfavorable neurological outcome (odds ratio [OR] 1.30, 95% CI 1.15-1.37; p < 0.001) and in-hospital mortality (OR 1.24, 95% CI 1.12-1.38; p < 0.001).

CONCLUSION

The PAR is a readily obtainable and independent prognostic indicator for patients with ROSC after OHCA, helping healthcare providers in predicting outcomes.

Canadian Cardiovascular Society/Canadian Cardiovascular Critical Care Society/Canadian Association of Interventional Cardiology Clinical Practice Update on Optimal Post Cardiac Arrest and Refractory Cardiac Arrest Patient Care

Survival to hospital discharge among patients with out-of-hospital cardiac arrest (OHCA) is low and important regional differences in treatment practices and survival have been described. Since the 2017 publication of the Canadian Cardiovascular Society's position statement on OHCA care, multiple randomized controlled trials have helped to better define optimal post cardiac arrest care. This working group provides updated guidance on the timing of cardiac catheterization in patients with ST-elevation and without ST-segment elevation, on a revised temperature control strategy targeting normothermia instead of hypothermia, blood pressure, oxygenation, and ventilation parameters, and on the treatment of rhythmic and periodic electroencephalography patterns in patients with a resuscitated OHCA. In addition, prehospital trials have helped craft new expert opinions on antiarrhythmic strategies (amiodarone or lidocaine) and outline the potential role for double sequential defibrillation in patients with refractory cardiac arrest when equipment and training is available. Finally, we advocate for regionalized OHCA care systems with admissions to a hospital capable of integrating their post OHCA care with comprehensive on-site cardiovascular services and provide guidance on the potential role of extracorporeal cardiopulmonary resuscitation in patients with refractory cardiac arrest. We believe that knowledge translation through national harmonization and adoption of contemporary best practices has the potential to improve survival and functional outcomes in the OHCA population.

Oxygenation During Venoarterial Extracorporeal Membrane Oxygenation: Physiology, Current Evidence, and a Pragmatic Approach to Oxygen Titration

OBJECTIVES

This review aims to: 1) identify the key circuit and patient factors affecting systemic oxygenation, 2) summarize the literature reporting the association between hyperoxia and patient outcomes, and 3) provide a pragmatic approach to oxygen titration, in patients undergoing peripheral venoarterial extracorporeal membrane oxygenation (ECMO).

DATA SOURCES

Searches were performed using PubMed, SCOPUS, Medline, and Google Scholar.

STUDY SELECTION

All observational and interventional studies investigating the association between hyperoxia, and clinical outcomes were included, as well as guidelines from the Extracorporeal Life Support Organization.

DATA EXTRACTION

Data from relevant literature was extracted, summarized, and integrated into a concise narrative review. For ease of reference a summary of relevant studies was also produced.

DATA SYNTHESIS

The extracorporeal circuit and the native cardiorespiratory circuit both contribute to systemic oxygenation during venoarterial ECMO. The ECMO circuit's contribution to systemic oxygenation is, in practice, largely determined by the ECMO blood flow, whereas the native component of systemic oxygenation derives from native cardiac output and residual respiratory function. Interactions between ECMO outflow and native cardiac output (as in differential hypoxia), the presence of respiratory support, and physiologic parameters affecting blood oxygen carriage also modulate overall oxygen exposure during venoarterial ECMO. Physiologically those requiring venoarterial ECMO are prone to hyperoxia. Hyperoxia has a variety of definitions, most commonly Pa o2 greater than 150 mm Hg. Severe hypoxia (Pa o2 > 300 mm Hg) is common, seen in 20%. Early severe hyperoxia, as well as cumulative hyperoxia exposure was associated with in-hospital mortality, even after adjustment for disease severity in both venoarterial ECMO and extracorporeal cardiopulmonary resuscitation. A pragmatic approach to oxygenation during peripheral venoarterial ECMO involves targeting a right radial oxygen saturation target of 94-98%, and in selected patients, titration of the fraction of oxygen in the mixture via the air-oxygen blender to target postoxygenator Pa o2 of 150-300 mm Hg.

CONCLUSIONS

Hyperoxia results from a range of ECMO circuit and patient-related factors. It is common during peripheral venoarterial ECMO, and its presence is associated with poor outcome. A pragmatic approach that avoids hyperoxia, while also preventing hypoxia has been described for patients receiving peripheral venoarterial ECMO.

Acute liver failure after out-of-hospital cardiac arrest: An observational study

RATIONALE

Apart from hypoxic hepatitis (HH), the hepatic consequences of out-of-hospital cardiac arrest (OHCA) have been little studied. This cohort study aimed to investigate the characteristics of liver dysfunction resulting from OHCA and its association with outcomes.

METHODS

Among the conventional static liver function tests used to define acute liver failure (ALF), we determined which one correlated more closely with the reference indocyanine green (ICG) clearance test in a series of OHCA patients from the CYRUS trial (NCT01595958). Subsequently, we assessed whether ALF, in addition to HH (i.e., acute liver injury), was an independent risk factor for death in a large cohort of OHCA patients admitted to two intensive care units between 2007 and 2017.

RESULTS

ICG clearance, available for 22 patients, was impaired in 17 (77.3%) cases. Prothrombin time (PT) ratio was the only static liver function test that correlated significantly (r = -0.66, p < 0.01) with ICG clearance and was therefore used to define ALF, with the usual cutoff of < 50%. Of the 418 patients included in the analysis (sex ratio: 1.4; median age: 64 [53-75] years; non-shockable rhythm: 73%), 67 (16.0%) presented with ALF, and 61 (14.6%) had HH at admission. On day 28, 337 (80.6%) patients died. Following multivariate analysis, ALF at admission, OHCA occurring at home, absence of bystander, non-cardiac cause of OHCA, low-flow duration ≥ 20 min, and SOFA score excluding liver subscore at admission were independently associated with day 28 mortality.

CONCLUSIONS

ALF occurred frequently after OHCA and, unlike HH, was independently associated with day 28 mortality.