Fred Rincon

Association between hyperoxia and mortality after stroke: a multicenter cohort study.

Objective:To test the hypothesis that hyperoxia was associated with higher in-hospital mortality in ventilated stroke patients admitted to the ICU. Design:Retrospective multicenter cohort study. Setting:Primary admissions of ventilated stroke patients with acute ischemic stroke, subarachnoid hemorrhage, and intracerebral hemorrhage who had arterial blood gases within 24 hours of admission to the ICU at 84 U.S. ICUs between 2003 and 2008. Patients were divided into three exposure groups: hyperoxia was defined as PaO2 ≥300 mm Hg (39.99 kPa), hypoxia as any PaO2<60 mm Hg (7.99 kPa) or PaO2/FiO2 ratio ⩽300, and normoxia, not defined as hyperoxia or hypoxia. The primary outcome was in-hospital mortality. Participants:Two thousand eight hundred ninety-four patients. Methods:Patients were divided into three exposure groups: hyperoxia was defined as PaO2 more than or equal to 300 mm Hg (39.99 kPa), hypoxia as any PaO2 less than 60 mm Hg (7.99 kPa) or PaO2/FIO2 ratio less than or equal to 300, and normoxia, not defined as hyperoxia or hypoxia. The primary outcome was in-hospital mortality. Interventions:Exposure to hyperoxia. Results:Over the 5-year period, we identified 554 ventilated patients with acute ischemic stroke (19%), 936 ventilated patients with subarachnoid hemorrhage (32%), and 1,404 ventilated patients with intracerebral hemorrhage (49%) of whom 1,084 (38%) were normoxic, 1,316 (46%) were hypoxic, and 450 (16%) were hyperoxic. Mortality was higher in the hyperoxia group as compared with normoxia (crude odds ratio 1.7 [95% CI 1.3-2.1]; p < 0.0001) and hypoxia groups (crude odds ratio, 1.3 [95% CI, 1.1–1.7]; p < 0.01). In a multivariable analysis adjusted for admission diagnosis, other potential confounders, the probability of being exposed to hyperoxia, and hospital-specific effects, exposure to hyperoxia was independently associated with in-hospital mortality (adjusted odds ratio, 1.2 [95% CI, 1.04–1.5]). Conclusion:In ventilated stroke patients admitted to the ICU, arterial hyperoxia was independently associated with in-hospital death as compared with either normoxia or hypoxia. These data underscore the need for studies of controlled reoxygenation in ventilated critically ill stroke populations. In the absence of results from clinical trials, unnecessary oxygen delivery should be avoided in ventilated stroke patients.

The epidemiology of admissions of nontraumatic subarachnoid hemorrhage in the United States.

BACKGROUND Subarachnoid hemorrhage (SAH) is the cause of 5% to 10% of strokes annually in the United States. OBJECTIVE To study the incidence and mortality trends of admissions of SAH from 1979 to 2008 using a nationally representative sample of all nonfederal acute-care hospitals in the United States: The National Hospital Discharge Survey. METHODS The sample was obtained from the hospital discharge records according to the International Classification of Disease, 9th Revision, Clinical Modification code 430. RESULTS We reviewed data on approximately 1 billion hospitalizations in the United States over a 30-year study period and identified 612,500 cases of SAH, which was more common in women (relative risk 1.71, 95% confidence interval 1.7-1.72) and nonwhite persons than white persons (relative risk 1.46, 95% confidence interval 1.4-1.5). The estimated incidence rate of admission after SAH was 7.2 to 9.0 per 100,000/year and did not significantly change over the study period. Overall, in-hospital mortality after SAH fell from 30% during the period from 1979 to 1983 to 20% during the subperiod from 2004 to 2008 (P = .03) and was lower in larger treating hospitals. The average days of care for SAH hospitalizations decreased, but the rate of discharge to long-term care facilities increased. CONCLUSION The incidence rate of admission after SAH has remained stable over the past 30 years. Total deaths and in-hospital mortality after SAH have decreased significantly. In-hospital mortality after SAH is lower in larger treating hospitals.

Significance of arterial hyperoxia and relationship with case fatality in traumatic brain injury: a multicentre cohort study

Objective In this retrospective multi-centre cohort study, we tested the hypothesis that hyperoxia was not associated with higher in-hospital case fatality in ventilated traumatic brain injury (TBI) patients admitted to the intensive care unit (ICU). Methods Admissions of ventilated TBI patients who had arterial blood gases within 24 h of admission to the ICU at 61 US hospitals between 2003 and 2008 were identified. Hyperoxia was defined as PaO2 ≥300 mm Hg (39.99 kPa), hypoxia as any PaO2 <60 mm Hg (7.99 kPa) or PaO2/FiO2 ratio ≤300 and normoxia, not defined as hyperoxia or hypoxia. The primary outcome was in-hospital case fatality. Results Over the 5-year period, we identified 1212 ventilated TBI patients, of whom 403 (33%) were normoxic, 553 (46%) were hypoxic and 256 (21%) were hyperoxic. The case-fatality was higher in the hypoxia group (224/553 [41%], crude OR 2.3, 95% CI 1.7-3.0, p<.0001) followed by hyperoxia (80/256 [32%], crude OR 1.5, 95% CI 1.1-2.5, p=.01) as compared to normoxia (87/403 [23%]). In a multivariate analysis adjusted for other potential confounders, the probability of being exposed to hyperoxia and hospital-specific characteristics, exposure to hyperoxia was independently associated with higher in-hospital case fatality adjusted OR 1.5, 95% CI 1.02-2.4, p=0.04. Conclusions In ventilated TBI patients admitted to the ICU, arterial hyperoxia was independently associated with higher in-hospital case fatality. In the absence of results from clinical trials, unnecessary oxygen delivery should be avoided in critically ill ventilated TBI patients.

Vascular cognitive impairment.

PURPOSE OF REVIEW Clinically apparent and subclinical forms of vascular disease including stroke are important causes of cognitive dysfunction. In this review, we will describe the current nomenclature for vascular cognitive impairment (VCI) from the histopathological and clinical perspectives to raise awareness among practitioners about the interaction between conventional and novel vascular risk factors and VCI, with an emphasis on the prevention and risk factor modification. RECENT FINDINGS There is substantial evidence from observational studies and clinical trials that conventional risk factors such as hypertension, diabetes, dyslipidemia, smoking, and atrial fibrillation play a role in the development of VCI. Additional novel risk factors such as the metabolic syndrome have been associated with cognitive dysfunction as well. Targeting these risk factors will minimize the burden of VCI in our aging population. SUMMARY The concept of VCI has evolved to describe a continuum of cognitive disorders in which vascular brain injury plays a role, ranging from mild cognitive impairment to dementia. Future research is needed to clarify the role of risk factor modification in limiting vascular brain injury to prevent VCI and progression to dementia.

Targeted temperature management after intracerebral hemorrhage (TTM-ICH): methodology of a prospective randomized clinical trial.

Rationale Intracerebral hemorrhage causes 15% of strokes annually in the United States, and there is currently no effective therapy. Aims and hypothesis This is a clinical trial designed to study the safety, feasibility, and efficacy of a protocol of targeted temperature management to moderate hypothermia in intracerebral hemorrhage patients. Methods The targeted temperature management after intracerebral hemorrhage trial is a prospective, single-center, interventional, randomized, parallel, two-arm (1:1) phase-II clinical trial with blinded end-point ascertainment. Intracerebral hemorrhage patients will be randomized within 18 h of symptom onset to either 72 h of targeted temperature management to moderate hypothermia (32–34°C) followed by a controlled rewarming at of 0·05–0·1°C per hour or 72 h of targeted temperature management to normothermia (36–37°C) using endovascular or surface cooling. Outcomes The primary outcome is the development of serious adverse events possibly and probably related to treatment. Secondary outcomes include in-hospital neurological deterioration between day 0–7, in-hospital mortality, functional outcome measured by the modified Rankin scale at discharge and 90 days, and effect of treatment allocation on cerebral edema and hematoma volume. Discussion Intracerebral hemorrhage remains the most severe form of stroke with limited options to improve survival. As the early resuscitation phase in the intensive care unit represents the greatest opportunity for impact on clinical outcome, it also appears to be the most promising window of opportunity to demonstrate a benefit when investigating aggressive treatments. Conclusion More research of novel therapies to improve outcomes after intracerebral hemorrhage is desperately needed. The results of the targeted temperature management after intracerebral hemorrhage clinical trial may provide additional information on the applicability of targeted temperature management after intracerebral hemorrhage.

Evidence-based guidelines for the management of large hemispheric infarction : a statement for health care professionals from the Neurocritical Care Society and the German Society for Neuro-intensive Care and Emergency Medicine.

Large hemispheric infarction (LHI), also known as malignant middle cerebral infarction, is a devastating disease associated with significant disability and mortality. Clinicians and family members are often faced with a paucity of high quality clinical data as they attempt to determine the most appropriate course of treatment for patients with LHI, and current stroke guidelines do not provide a detailed approach regarding the day-to-day management of these complicated patients. To address this need, the Neurocritical Care Society organized an international multidisciplinary consensus conference on the critical care management of LHI. Experts from neurocritical care, neurosurgery, neurology, interventional neuroradiology, and neuroanesthesiology from Europe and North America were recruited based on their publications and expertise. The panel devised a series of clinical questions related to LHI, and assessed the quality of data related to these questions using the Grading of Recommendation Assessment, Development and Evaluation guideline system. They then developed recommendations (denoted as strong or weak) based on the quality of the evidence, as well as the balance of benefits and harms of the studied interventions, the values and preferences of patients, and resource considerations.

Acute Lung Injury in Patients with Subarachnoid Hemorrhage: A Nationwide Inpatient Sample Study

OBJECTIVE To determine national trends for patients with subarachnoid hemorrhage (SAH) and pulmonary complications including acute respiratory distress syndrome (ARDS). METHODS The Nationwide Inpatient Sample database was used to sample 193,209 admissions for SAH with and without ARDS during the period 1993-2008 using International Classification of Diseases, Ninth Revision, Clinical Modification coding. A multivariate stepwise regression analysis was performed. RESULTS The incidence of ARDS in patients with SAH increased from 35.51% in 1993 to 37.60% in 2008. However, the overall mortality in patients with SAH and in patients with SAH and ARDS decreased in the same period, from 42.30% to 31.99% and from 75.13% to 60.76%, respectively. Multivariate analysis showed that the predictors of developing ARDS in patients with SAH include older age; larger hospital size; and comorbidities such as epilepsy, cardiac arrest, sepsis, congestive heart failure, hypertension, chronic obstructive pulmonary disease, hematologic dysfunction, renal dysfunction, and neurologic dysfunction. Predictors of mortality in patients with SAH include age and hospital complications, such as coronary artery disease, ARDS, cancer, hematologic dysfunction, and renal dysfunction. CONCLUSIONS Patients with SAH are at increased risk of developing ARDS. The identification of certain risk factors may alert and aid practitioners in preventing worsening disease.

Defining Futile and Potentially Inappropriate Interventions: A Policy Statement From the Society of Critical Care Medicine Ethics Committee

Objectives: The Society of Critical Care Medicine and four other major critical care organizations have endorsed a seven-step process to resolve disagreements about potentially inappropriate treatments. The multiorganization statement (entitled: An official ATS/AACN/ACCP/ESICM/SCCM Policy Statement: Responding to Requests for Potentially Inappropriate Treatments in Intensive Care Units) provides examples of potentially inappropriate treatments; however, no clear definition is provided. This statement was developed to provide a clear definition of inappropriate interventions in the ICU environment. Design: A subcommittee of the Society of Critical Care Medicine Ethics Committee performed a systematic review of empirical research published in peer-reviewed journals as well as professional organization position statements to generate recommendations. Recommendations approved by consensus of the full Society of Critical Care Medicine Ethics Committees and the Society of Critical Care Medicine Council were included in the statement. Measurements and Main Results: ICU interventions should generally be considered inappropriate when there is no reasonable expectation that the patient will improve sufficiently to survive outside the acute care setting, or when there is no reasonable expectation that the patient’s neurologic function will improve sufficiently to allow the patient to perceive the benefits of treatment. This definition should not be considered exhaustive; there will be cases in which life-prolonging interventions may reasonably be considered inappropriate even when the patient would survive outside the acute care setting with sufficient cognitive ability to perceive the benefits of treatment. When patients or surrogate decision makers demand interventions that the clinician believes are potentially inappropriate, the seven-step process presented in the multiorganization statement should be followed. Clinicians should recognize the limits of prognostication when evaluating potential neurologic outcome and terminal cases. At times, it may be appropriate to provide time-limited ICU interventions to patients if doing so furthers the patient’s reasonable goals of care. If the patient is experiencing pain or suffering, treatment to relieve pain and suffering is always appropriate. Conclusions: The Society of Critical Care Medicine supports the seven-step process presented in the multiorganization statement. This statement provides added guidance to clinicians in the ICU environment.

Current pathophysiological concepts in cerebral small vessel disease.

The association between cerebral small vessel disease (SVD) – in the form of white matter lesions, infarctions, and hemorrhages – with vascular cognitive impairment (VCI), has mostly been deduced from observational studies. Pathological conditions affecting the small vessels of the brain and leading to SVD have suggested plausible molecular mechanisms involved in vascular damage and their impact on brain function. However, much still needs to be clarified in understanding the pathophysiology of VCI, the role of neurodegenerative processes such as Alzheimer’s disease, and the impact of aging itself. In addition, both genetic predispositions and environmental exposures may potentiate the development of SVD and interact with normal aging to impact cognitive function and require further study. Advances in technology, in the analysis of genetic and epigenetic data, neuroimaging such as magnetic resonance imaging, and new biomarkers will help to clarify the complex factors leading to SVD and the expression of VCI.

Intracerebral hemorrhage: getting ready for effective treatments.

Purpose of reviewSpontaneous intracerebral hemorrhage (ICH) is the most devastating type of stroke and a leading cause of disability and mortality in the United States and the rest of the world. The purpose of this article is to review recent advances in the management of spontaneous intracerebral hemorrhage. Recent findingsAlthough no interventions have consistently shown an improvement of mortality or functional outcomes after ICH, results from multicenter prospective randomized controlled trials have shown that early hemostasis to prevent hematoma growth, removal of clot by surgical or minimally invasive interventions, clearance of intraventricular hemorrhage, and adequate blood pressure control for the optimization of cerebral perfusion pressure may constitute the most important therapeutic goals to ameliorate secondary neurological damage, decrease mortality, and improve functional outcomes after ICH. ConclusionSeveral promising methods may be ready for routine clinical use in a few years to decrease disability and mortality from ICH.