Surviving cardiac arrest (CA) requires a longitudinal approach with multiple levels of responsibility, including fostering a culture of action by increasing public awareness and training, optimization of resuscitation measures including frequent updates of guidelines and their timely implementation into practice, and optimization of post-CA care. This clearly goes beyond resuscitation and targeted temperature management. Brain-directed physiologic goals should dictate the post-CA management, as accumulating evidence suggests that the degree of hypoxic brain injury is the main determinant of survival, regardless of the etiology of arrest. Early assessment of the need for further hemodynamic and electrophysiologic cardiac interventions, adjusting ventilator settings to avoid hyperoxia/hypoxia while targeting high-normal to mildly elevated PaCO, maintaining mean arterial blood pressures >65 mmHg, evaluating for and treating seizures, maintaining euglycemia, and aggressively pursuing normothermia are key steps in reducing the bioenergetic failure that underlies secondary brain injury. Accurate neuroprognostication requires a multimodal approach with standardized assessments accounting for confounders while recognizing the importance of a delayed prognostication when there is any uncertainty regarding outcome. The concept of a highly specialized post-CA team with expertise in the management of post-CA syndrome (mindful of the brain-directed physiologic goals during the early post-resuscitation phase), TTM, and neuroprognostication, guiding the comprehensive care to the CA survivor, is likely cost-effective and should be explored by institutions that frequently care for these patients. Finally, providing tailored rehabilitation care with systematic reassessment of the needs and overall goals is key for increasing independence and improving quality-of-life in survivors, thereby also alleviating the burden on families. Emerging evidence from multicenter collaborations advances the field of resuscitation at an incredible pace, challenging previously well-established paradigms. There is no more room for "conventional wisdom" in saving the survivors of cardiac arrest.

Objectives: To characterize approaches to neurologic outcome prediction by practitioners who assess prognosis in unconscious cardiac arrest individuals, and assess compliance to available guidelines. Design: International cross-sectional study. Setting: We administered a web-based survey to members of Neurocritical Care Society, Society of Critical Care Medicine, and American Academy of Neurology who manage unconscious cardiac arrest patients to characterize practitioner demographics and current neuroprognostic practice patterns. Subjects: Physicians that are members of aforementioned societies who care for successfully resuscitated cardiac arrest individuals. Interventions: Not applicable. Measurements and Main Results: A total of 762 physicians from 22 countries responses were obtained. A significant proportion of respondents used absent corneal reflexes (33.5%) and absent pupillary reflexes (36.2%) at 24 hours, which is earlier than the recommended 72 hours in the standard guidelines. Certain components of the neurologic examination may be overvalued, such as absent motor response or extensor posturing, which 87% of respondents considered being very or critically important prognostic indicators. Respondents continue to rely on myoclonic status epilepticus and neuroimaging, which were favored over median nerve somatosensory evoked potentials for prognostication, although the latter has been demonstrated to have a higher predictive value. Regarding definitive recommendations based on poor neurologic prognosis, most physicians seem to wait until the postarrest timepoints proposed by current guidelines, but up to 25% use premature time windows. Conclusions: Neuroprognostic approaches to hypoxic-ischemic encephalopathy vary among physicians and are often not consistent with current guidelines. The overall inconsistency in approaches and deviation from evidence-based recommendations are concerning in this disease state where mortality is so integrally related to outcome prediction.

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Leukotriene (LT) generation has been implicated in the pathogenesis of the acute respiratory distress syndrome, ARDS. In the present study, we analysed broncho-alveolar lavage fluids of patients on mechanical ventilation because of ARDS (17 samples taken from 9 patients) or because of cardiogenic edema (8 samples taken from 6 patients) and of healthy volunteers (10 samples from different donors). LTs were separated as methylated and non-methylated compounds using different HPLC procedures, and were identified by chromatographic mobility, on-line UV-spectrum analysis and post HPLC immunoreactivity. In the lavage samples of the healthy volunteers and the patients with cardiogenic edema, no LTs were detected by these techniques (detection limit congruent to 0.1-0.2 ng/ml lavage fluid). By contrast, in 15 out of 17 samples from patients with ARDS LTB4 or its metabolites 20-OH-LTB4 and 20-COOH-LTB4 were detected. The endproduct of omega-oxidation, 20-COOH-LTB4, represented the quantitatively predominant compound, detected in the range of 0.3-2.6 ng/ml perfusate. We conclude that the chemotactic agent LTB4 may be involved in the amplification of inflammatory events encountered in ARDS, and that the oxidized metabolites of LTB4 are particularly suitable for monitoring lung leukotriene generation under conditions of neutrophil efflux and oxidative stress.

Objectives: End-of-life care and decisions on withdrawal of life-sustaining therapies vary across countries, which may affect the feasibility of future multicenter cardiac arrest trials. In Brazil, withdrawal of life-sustaining therapy is reportedly uncommon, allowing the natural history of postcardiac arrest hypoxic-ischemic brain injury to present itself. We aimed to characterize approaches to neuroprognostication of cardiac arrest survivors among physicians in Brazil. Design: Cross-sectional study. Setting: Between August 2, 2019, and July 31, 2020, we distributed a web-based survey to physicians practicing in Brazil. Subjects: Physicians practicing in Brazil and members of the Brazilian Association of Neurointensive Care, who care for patients resuscitated following cardiac arrest. Interventions: Not applicable. Measurements and Main Results: Responses from 185 physicians were obtained. Pupillary reflexes, corneal reflexes, and motor responses were considered critical to prognostication, whereas neuroimaging and electroencephalography were also regarded as important. For patients without targeted temperature management, absent pupillary and corneal reflexes at 24 hours postarrest were considered strongly predictive of poor neurologic outcome by 31.8% and 33.0%, respectively. For targeted temperature management-treated patients, absent pupillary and corneal reflexes at 24-hour postrewarming were considered prognostic by 22.9% and 20.0%, respectively. Physicians felt comfortable making definitive prognostic recommendations at day 6 postarrest or later (34.2%) for nontargeted temperature management-treated patients, and at day 6 postrewarming (20.4%) for targeted temperature management-treated patients. Over 90% believed that improving neuroprognostic accuracy would affect end-of-life decision-making. Conclusions: There is significant variability in neuroprognostic approaches to postcardiac arrest patients and timing of prognostic studies among Brazilian physicians, with practices frequently deviating from current guidelines, underscoring a need for greater neuroprognostic accuracy. Nearly all physicians believed that improving neuroprognostication will impact end-of-life decision-making. Given the tendency to delay prognostic recommendations while using similar neuroprognostic tools, Brazil offers a unique cohort in which to examine the natural history of hypoxic-ischemic brain injury in future studies.