Comparison of out of hospital cardiac arrest due to acute brain injury vs other causes.

BACKGROUND: Acute brain injury (ABI) can cause out of hospital cardiac arrest (OHCA). The aim of this study was to compare clinical features, mortality and potential for organ donation in patients with OHCA due to ABI vs other causes. METHODS: From January 2017 to December 2018, all adult patients presenting to ED for OHCA were considered for the study. Two physicians established the definitive cause of OHCA, according to clinical, laboratory, diagnostic imaging and autoptic findings. Clinical features in patients with OHCA due to ABI or other causes were compared. RESULTS: 280 patients were included in the analysis. ABI was the third most frequent cause of OHCA (21, 7.5%); ABIs were 8 subarachnoid hemorrhage, 8 intracerebral hemorrhage, 2 ischemic stroke, 2 traumatic spinal cord injury and 1 status epilepticus respectively. Neurological prodromes such as seizure, headache and focal neurological signs were significantly more frequent in patients with OHCA due to ABI (OR 5.34, p = 0.03; OR 12.90, p = 0.02; and OR 66.53, p < 0.01 respectively) while among non-neurological prodromes chest pain and dyspnea were significantly more frequent in patients with OHCA due to other causes (OR 14.5, p < 0.01; and OR 10.4, p = 0.02 respectively). Anisocoria was present in 19% of patients with OHCA due to ABI vs 2.7% due to other causes (OR 8.47, p < 0.01). In 90.5% of patients with ABI and in 53.1% of patients with other causes the first cardiac rhythm was non shockable (OR 8.1; p = 0.05). Multivariate logistic regression analysis revealed that older age, active smoking, post-traumatic OHCA, neurological prodromes, anisocoria at pupillary examination were independently associated with OHCA due to ABI. Patients with ABI showed a higher mortality compared with the other causes group (19 pts., 90.5% versus 167 pts., 64.5%; p = 0.015). Potential organ donors were more frequent among ABI than other causes group (10 pts., 47.6% vs 75 pts., 28.9%) however the difference did not reach the statistical significance (p = 0.07). CONCLUSIONS: ABI is the third cause of OHCA. Neurological prodromes, absence of chest pain and dyspnea before cardiac arrest, anisocoria and initial non-shockable rhythm might suggest a neurological etiology of the cardiac arrest. Patients with OHCA due to ABI has an unfavorable outcome, however, they could be candidate to organ donation.

Applying the Boston syncope criteria to near syncope.

BACKGROUND: We recently demonstrated that near-syncope patients are as likely as syncope patients to experience adverse outcomes. The Boston Syncope Criteria (BSC) identify patients with syncope unlikely to have adverse outcomes and reduce hospitalizations. It is unclear whether these guidelines could reduce hospitalization in near syncope as well. OBJECTIVE: To determine if BSC accurately predict which near-syncope patients require hospitalization. METHODS: A prospective observational study enrolled from August 2007 to October 2008 consecutive emergency department (ED) patients (aged > 18 years) with near syncope. BSC were first employed assuming that any patient with risk factors for adverse outcomes should be admitted, and then utilized using a modified rule: if the etiology of near syncope is dehydration or vasovagal, and ED work-up is normal, patients may be discharged even with risk factors. Outcomes were identified by chart review and 30-day follow-up calls. RESULTS: Of 244 patients with near syncope, 111 were admitted, with 49 adverse outcomes. No adverse outcomes occurred among discharged patients. If BSC had been followed strictly, another 41 patients with risk factors would have been admitted and 34 discharged, a 3% increase in admission rate. However, using the modified criteria, only 68 patients would have required admission, a 38% reduction in admission, with no missed adverse outcomes on follow-up. CONCLUSION: Although near-syncope patients may have risk factors for adverse outcomes similar to those with syncope, if the etiology of near syncope is dehydration or vasovagal, and ED work-up is normal, these patients may be discharged even with risk factors.

Do outcomes of near syncope parallel syncope?

BACKGROUND: Limited information on the evaluation of emergency department (ED) patients complaining of "near syncope" exists. Multiple studies of syncope exclude near syncope claiming near syncope is poorly defined and its definition is nonuniform. OBJECTIVE: The aim of this study was to determine the incidence of critical interventions or adverse outcomes associated with near syncope and compare these outcomes with syncope. METHODS: Prospective, observational study enrolling (August 2007-October 2008) consecutive ED patients (age, ≥18 years) presenting with near syncope was conducted. Near syncope was defined as an episode in which the patient felt they might lose consciousness but did not. Critical intervention/adverse outcome was defined as hemorrhage, cardiac ischemia/intervention, alteration in antidysrhythmics, pacemaker/defibrillator placement, sepsis, stroke, death, dysrhythmia, sepsis, pulmonary embolus, or carotid stenosis. Primary outcome was an adverse outcome or critical intervention in hospital or less than 30 days. Near syncope and syncope outcomes and admission rates were compared using the χ(2) test. RESULTS: After 1870 patients were screened, 244 met the study definition. Of the 244 patients, follow-up was achieved in 242 (99%). Emergency department hospitalization or 30-day adverse outcomes occurred in 49 (20%) of 244 compared with 68 (23%) of 293 of patients with syncope (P = .40). The most common adverse outcomes/critical interventions were hemorrhage (n = 6), bradydysrhythmia (n = 6), alteration in antidysrhythmics (n = 6), and sepsis (n = 10). Of patients with near syncope, 49% were admitted compared with 69% with syncope (P = .001). CONCLUSION: Patients with near syncope are as likely those with syncope to experience critical interventions or adverse outcomes; however, near-syncope patients are less likely to be admitted. Given similar risk of adverse outcomes for near syncope and syncope, future studies are warranted to improve the treatment of ED patients with near syncope.

The microcirculation as a diagnostic and therapeutic target in sepsis.

The microcirculation is defined as the smallest vessels where gas and nutrient exchange with tissues takes place. One of its primary functions is to ensure adequate oxygen delivery to meet the oxygen demands of tissue cells. Previous data from clinical and experimental studies and the recent development of new imaging modalities, such as Orthogonal Polarization Spectral videomicroscopy and Sidestream Dark Field imaging, have helped to identify the crucial role that microcirculation plays in sepsis. If not corrected, microcirculatory dysfunction can lead to respiratory distress in tissue cells and subsequent organ failure, even in the absence of global hemodynamic deficiency. In the present review, we will address past and recent developments regarding the role of the microcirculation as an important target in the pathogenesis of sepsis and its progression to multiple organ failure. Accordingly, we identify the microcirculation as an important diagnostic and therapeutic target for treatment in sepsis.