J. Dedrick Jordan

Cerebral autoregulation and acute ischemic stroke

Cerebral autoregulation tightly controls blood flow to the brain by coupling cerebral metabolic demand to cerebral perfusion. In the setting of acute brain injury, such as that caused by ischemic stroke, the continued precise control of cerebral blood flow (CBF) is vital to prevent further injury. Chronic as well as acute elevations in blood pressure are frequently associated with stroke, therefore, understanding the physiological response of the brain to the treatment of hypertension is clinically important. Physiological data obtained in patients with acute ischemic stroke provide no clear evidence that there are alterations in the intrinsic autoregulatory capacity of cerebral blood vessels, except perhaps in infarcted tissue. While it is likely safe to modestly reduce blood pressure by 10-15 mm Hg in most patients with acute ischemic stroke, to date, there are no controlled trial data to indicate that reducing blood pressure is beneficial. There may be subgroups, such as those with persistent large vessel occlusion, large infarcts with edema causing increased intracranial pressure or local mass effect, or chronic hypertension, in which blood pressure reduction may lead to impaired cerebral perfusion in noninfarcted tissue.

Acute treatment of blood pressure after ischemic stroke and intracerebral hemorrhage

Blood pressure elevation in the setting of acute ischemic stroke and intracerebral hemorrhage is common. Controversy exists as to the optimal management of elevated blood pressure in this patient population. This article reviews the available clinical data that guides acute blood pressure management and how this may affect clinical outcomes. Furthermore, it examines how these data have led to controversies in their clinical application.

The Role of Statin Therapy in Hemorrhagic Stroke.

The 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase inhibitors (statins) are the most widely utilized class of cholesterol‐lowering agents, carrying multiple indications for both primary and secondary cardiovascular risk reduction. Concern was raised by previously published post hoc analyses and observational studies that noted an increased risk of hemorrhagic stroke in patients receiving a statin. Subsequent studies have demonstrated conflicting results regarding the role of statin therapy on hemorrhagic stroke risk and patient outcomes. New evidence suggests that statins taken prior to or continued during admission for intracerebral hemorrhage (ICH) may be associated with positive outcomes. Evidence also suggests deleterious outcomes resulting from the abrupt discontinuation of statins upon hospital admission for multiple disease states including ICH. Conflicting data also exist for the use of statins following aneurysmal subarachnoid hemorrhage (aSAH). Recent evidence suggests statins started during admission for aSAH confer no additional benefit in reducing delayed ischemic neurologic deficits despite initial positive results. Larger scale evaluation of the role of statin therapy following hemorrhagic stroke is warranted. The available literature is reviewed to provide guidance for therapeutic decision making.

Serum GFAP and UCH-L1 for prediction of absence of intracranial injuries on head CT (ALERT-TBI): a multicentre observational study

BACKGROUND More than 50 million people worldwide sustain a traumatic brain injury (TBI) annually. Detection of intracranial injuries relies on head CT, which is overused and resource intensive. Blood-based brain biomarkers hold the potential to predict absence of intracranial injury and thus reduce unnecessary head CT scanning. We sought to validate a test combining ubiquitin C-terminal hydrolase-L1 (UCH-L1) and glial fibrillary acidic protein (GFAP), at predetermined cutoff values, to predict traumatic intracranial injuries on head CT scan acutely after TBI. METHODS This prospective, multicentre observational trial included adults (≥18 years) presenting to participating emergency departments with suspected, non-penetrating TBI and a Glasgow Coma Scale score of 9-15. Patients were eligible if they had undergone head CT as part of standard emergency care and blood collection within 12 h of injury. UCH-L1 and GFAP were measured in serum and analysed using prespecified cutoff values of 327 pg/mL and 22 pg/mL, respectively. UCH-L1 and GFAP assay results were combined into a single test result that was compared with head CT results. The primary study outcomes were the sensitivity and the negative predictive value (NPV) of the test result for the detection of traumatic intracranial injury on head CT. FINDINGS Between Dec 6, 2012, and March 20, 2014, 1977 patients were recruited, of whom 1959 had analysable data. 125 (6%) patients had CT-detected intracranial injuries and eight (<1%) had neurosurgically manageable injuries. 1288 (66%) patients had a positive UCH-L1 and GFAP test result and 671 (34%) had a negative test result. For detection of intracranial injury, the test had a sensitivity of 0·976 (95% CI 0·931-0·995) and an NPV of 0·996 (0·987-0·999). In three (<1%) of 1959 patients, the CT scan was positive when the test was negative. INTERPRETATION These results show the high sensitivity and NPV of the UCH-L1 and GFAP test. This supports its potential clinical role for ruling out the need for a CT scan among patients with TBI presenting at emergency departments in whom a head CT is felt to be clinically indicated. Future studies to determine the value added by this biomarker test to head CT clinical decision rules could be warranted. FUNDING Banyan Biomarkers and US Army Medical Research and Materiel Command.

Development of a neuro early mobilisation protocol for use in a neuroscience intensive care unit

OBJECTIVE Through evaluation of the literature and working with a team of multidisciplinary healthcare providers, our objective was to refine an interprofessional Neuro Early Mobilisation Protocol for complex patients in the Neuroscience Intensive Care Unit. RESEARCH METHODOLOGY Using the literature as a guide, key stakeholders, from multiple professions, designed and refined a Neuro Early Mobilisation Protocol. SETTING This project took place at a large academic medical center in the southeast United States classified as both a Level I Trauma Center and Comprehensive Stroke Center. MAIN OUTCOME MEASURES Goals for protocol development were to: (1) simplify the protocol to allow for ease of use, (2) make the protocol more generalizable to the patient population cared for in the Neuroscience Intensive Care Unit, (3) receive feedback from those using the original protocol on ways to improve the protocol and (4) ensure patients were properly screened for inclusion and exclusion in the protocol. RESULTS Using expert feedback and the evidence, an evidence-based Neuro Early Mobilisation Protocol was created for use with all patients in the Neuroscience Intensive Care Unit. CONCLUSION Future work will consist of protocol implementation and evaluation in order to increase patient mobilisation in the Neuroscience Intensive Care Unit.

Correction to: Influence of Single-Dose Antibiotic Prophylaxis for Early-Onset Pneumonia in High-Risk Intubated Patients

Due to an error introduced during the production process, J. Dedrick Jordan’s name was improperly tagged in the original publication of this article. It is tagged correctly here.

Acute Blood Pressure Management After Ischemic Stroke

Although the long-term treatment of hypertension is effective for secondary stroke prevention, the optimal management of blood pressure in the setting of acute ischemic stroke has been controversial. This chapter discusses the available evidence and current guidelines supporting the management of blood pressure in the setting of acute ischemic stroke. For patients that are candidates for thrombolysis, reduction and maintenance of the BP within the current guidelines is indicated as it likely reduces the risk of hemorrhagic complications. For all other patients, there is no clear benefit and potentially harm for acute blood pressure reduction.