Transcranial volumetric imaging using a conformal ultrasound patch.

Accurate and continuous monitoring of cerebral blood flow is valuable for clinical neurocritical care and fundamental neurovascular research. Transcranial Doppler (TCD) ultrasonography is a widely used non-invasive method for evaluating cerebral blood flow, but the conventional rigid design severely limits the measurement accuracy of the complex three-dimensional (3D) vascular networks and the practicality for prolonged recording. Here we report a conformal ultrasound patch for hands-free volumetric imaging and continuous monitoring of cerebral blood flow.

A combined stability function to quantify flood risks to pedestrians and vehicle occupants.

With the increase of the frequency and severity of flooding events, coupled with population growth, the risks posed to people from flooding is ever more apparent. This paper proposes a methodology to examine the risks posed to vehicles' occupants and pedestrians simultaneously in an urban context. Through considering stability functions of a range of vehicle types and pedestrian, a risk assessment profile for a vehicle occupant was derived.

A Case Report of Thalamic Infarction after Lumbar Drain: A Unique Cause of Perioperative Stroke?

In the case presented, a patient has an unexplained episode of hypertension during aneurysm clipping. Following the procedure, the patient was discovered to have bilateral thalamic infarctions unrelated to the vascular location of the aneurysm. After a review of the case, it becomes apparent that intracranial hypotension caused by lumbar over drainage of cerebrospinal fluid (CSF) is the likely cause of both the episode of intraoperative hypertension and the thalamic infarcts.

Emergency Neurological Life Support: Intracerebral Hemorrhage.

Intracerebral hemorrhage (ICH) is a subset of stroke due to spontaneous bleeding within the parenchyma of the brain. It is potentially lethal, and survival depends on ensuring an adequate airway, proper diagnosis, and early management of several specific issues such as blood pressure, coagulopathy reversal, and surgical hematoma evacuation for appropriate patients. ICH was chosen as an Emergency Neurological Life Support (ENLS) protocol because intervention within the first hours may improve outcome, and it is critical to have site-specific protocols to drive care quickly and efficiently.

Perioperative Vision Loss in Cervical Spinal Surgery.

Study Design: Retrospective multicenter case series.

Objective: To assess the rate of perioperative vision loss following cervical spinal surgery.

Methods: Medical records for 17 625 patients from 21 high-volume surgical centers from the AOSpine North America Clinical Research Network who received cervical spine surgery (levels from C2 to C7) between January 1, 2005, and December 31, 2011, inclusive, were reviewed to identify occurrences of vision loss following surgery.

Venous air embolus during prone cervical spine fusion: case report.

Venous air embolism (VAE) is a known neurosurgical complication classically and most frequently occurring in patients undergoing posterior cranial fossa or cervical spine surgery in a sitting or semi-sitting position. The authors present a case of VAE that occurred during posterior cervical spine surgery in a patient in the prone position, a rare intraoperative complication. The patient was a 65-year-old man who was undergoing a C1-2 fusion for a nonunion of a Type II dens fracture and developed a VAE.

Randomized pilot trial of intensive management of blood pressure or volume expansion in subarachnoid hemorrhage (IMPROVES).

Background: Volume expansion and hypertension are widely used for the hemodynamic management of patients with subarachnoid hemorrhage.

Objective: To investigate the feasibility, adherence, and retention in a trial of volume expansion and blood pressure manipulation to prevent delayed cerebral ischemia.

Methods: A randomized pilot trial using a 2-way factorial design allocating patients within 72 hours of subarachnoid hemorrhage to either normovolemia (NV) or volume expansion (HV) and simultaneously to conventional (CBP) or augmented blood pressure (ABP) for 10 days.

An epidural blood patch causing acute neurologic dysfunction necessitating a decompressive laminectomy.

Objectives: One risk with placement of an epidural blood patch (EDBP) is spinal cord or nerve root compression resulting from the epidural blood volume injected, a complication necessitating immediate surgical decompression. We could not find a previous report of this in the literature. Here, we review and discuss one such case.

Ultrasound-based imaging in neurocritical care patients: a review of clinical applications.

Objective: To analyze the diagnostic, monitoring, and procedural applications of ultrasound (US) imaging in neurocritical care (NCC) patients.

Method: US imaging has been extensively validated in various subset of critically ill patients, but not specifically in the NCC population. We reviewed the clinical applications of US imaging for heart, vascular, brain, and lung evaluation and for possible procedural uses in NCC patients.

Cerebral blood flow and the injured brain: how should we monitor and manipulate it?

Purpose Of Review: Cerebral ischemia plays a major role in the pathophysiology of the injured brain, including traumatic brain injury and subarachnoid hemorrhage, thus improvement in outcome may necessitate monitoring and optimization of cerebral blood flow (CBF). To interpret CBF results in a meaningful way, it may be necessary to quantify cerebral autoregulation as well as cerebral metabolism. This review addresses the recent evidence related to the changes in CBF and its monitoring/management in traumatic brain injury.

Current practices of triple-H prophylaxis and therapy in patients with subarachnoid hemorrhage.

Background: Medical management of cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) includes hypertensive, hypervolemic, and hemodilution ("triple-H") therapy. However, there is little information regarding the indications and guidance used to initiate and adjust triple-H therapy.

Methods: A 43-item questionnaire was e-mailed to 375 members of the Neurocritical Care Society.

Adenosine-induced transient asystole for intracranial aneurysm surgery: a retrospective review.

Unlabelled: BRIEF SUMMARY: We describe the use of adenosine-induced cardiac arrest to facilitate intracranial aneurysm clip ligation.

Background: Cerebral aneurysms are highly variable which may result in difficult surgical exposure for clip ligation in select cases. Secure clip placement is often not feasible without temporarily decompressing the aneurysm.

Clinical experience with transcranial Doppler ultrasonography as a confirmatory test for brain death: a retrospective analysis.

Background: Transcranial Doppler (TCD) ultrasonography to demonstrate cerebral circulatory arrest (CCA) is a confirmatory test for brain death (BD). The primary aim of this retrospective study was to evaluate the practical utility of TCD to confirm BD when clinical diagnosis was not feasible due to confounding factors. Secondary aims were to evaluate the reasons for inability of TCD to confirm BD and to assess the outcome of patients not brain dead according to the TCD criteria.

Paradoxical emboli secondary to hepatic pathology: common or coincidental?

Paradoxical cerebral emboli from cardiac and pulmonary sources are well described in the peer-reviewed literature. We outline a case with a hepatic etiology and describe diagnostic and management options. Though this paper represents the first documentation of such, we believe that transpulmonary shunting with concurrent paradoxical cerebral microemboli is more prevalent than recognized.

Postoperative cognitive dysfunction in the elderly.

Despite improvement in surgical techniques, anesthetic management, and intensive care, a significant number of elderly patients develop postoperative cognitive decline. Postoperative cognitive dysfunction (POCD) is a postoperative memory or thinking impairment that has been corroborated by neuropsychological testing, for which increasing age is the leading risk factor. POCD is multifactorial in origin, but it remains unclear whether its occurrence is a result of surgery or general anesthesia.

Prolonged propofol anesthesia is not associated with an increase in blood lactate.

Background: Lactic acidosis is considered an early sign of propofol infusion syndrome. In this study, we investigated the changes in lactate and pH with propofol versus volatile anesthesia (VA) of long duration.

Methods: Demographic and intraoperative data were recorded retrospectively from the anesthesia records of patients who underwent elective spine surgery longer than 8 h.

Cerebral autoregulation and anesthesia.

Purpose Of Review: This review will examine the recent literature on anesthesia and monitoring techniques in relation to cerebral autoregulation. We will discuss the effect of physiologic and pharmacological factors on cerebral autoregulation alongside its clinical relevance with the help of new evidence.

Recent Findings: Intravenous anesthesia, such as combination of propofol and remifentanil, provides best preservation of autoregulation.

Esmolol blunts postoperative hemodynamic changes after propofol-remifentanil total intravenous fast-track neuroanesthesia for intracranial surgery.

Study Objective: To investigate whether esmolol is effective in attenuating postoperative hemodynamic changes related to sympathetic overdrive.

Design: Clinical study.

Setting: Operating room of a university hospital.

Accuracy of transcranial Doppler ultrasonography and single-photon emission computed tomography in the diagnosis of angiographically demonstrated cerebral vasospasm.

Object: The goal of this study was to assess the accuracy of the routine clinical use of transcranial Doppler (TCD) ultrasonography and SPECT in predicting angiographically demonstrated vasospasm.

Methods: Following receipt of institutional review board approval, the authors reviewed the records of patients with subarachnoid hemorrhage who had been admitted between 2004 and 2005 and underwent TCD ultrasonography and SPECT evaluations within 24 hours of cerebral angiography. Patients were categorized based on the presence or absence of vasospasm and/or hypoperfusion in the anterior cerebral arteries (ACAs), middle cerebral arteries (MCAs), and basilar arteries (BAs) or posterior cerebral arteries (PCAs) according to each imaging modality.