Improving Outcome in Severe Myasthenia Gravis and Guillain-Barré Syndrome.

When progressive and severe, myasthenia gravis and Guillain-Barré syndrome may have the potential for fatal and unfavorable clinical outcomes. Regardless of important differences in their clinical course, the development of weakness of oropharyngeal muscles and respiratory failure with requirement of mechanical ventilation is the main driver of poor prognosis in both conditions. The need for prolonged mechanical ventilation is particularly relevant because it immobilizes the patient and care becomes extraordinarily complex due to daily risks of systemic complications. Additionally, patients with myasthenia gravis often require long-term immunosuppressive treatments with associated toxicity and infectious risks. Unlike myasthenia gravis, the recovery period is prolonged in Guillain-Barré syndrome, but often favorable, even in the more severely affected patients. Outcome, for a large part, is determined by expert neurocritical care.

The Delphi Delirium Management Algorithms. A practical tool for clinicians, the result of a modified Delphi expert consensus approach.

Delirium is common in hospitalised patients, and there is currently no specific treatment. Identifying and treating underlying somatic causes of delirium is the first priority once delirium is diagnosed. Several international guidelines provide clinicians with an evidence-based approach to screening, diagnosis and symptomatic treatment. However, current guidelines do not offer a structured approach to identification of underlying causes. A panel of 37 internationally recognised delirium experts from diverse medical backgrounds worked together in a modified Delphi approach via an online platform. Consensus was reached after five voting rounds. The final product of this project is a set of three delirium management algorithms (the Delirium Delphi Algorithms), one for ward patients, one for patients after cardiac surgery and one for patients in the intensive care unit.

Locked in from fulminant GBS after lumbar spine surgery.

Guillain-Barré syndrome (GBS) describes a neurological syndrome characterised by acute, areflexic paralysis, often preceded by an immune stimulating event such as infection or surgery. Spinal surgery as an inciting event is very uncommon with few reported cases. When paraparesis develops in close proximity of surgery, surgical complications should be considered, but if an asymptomatic clinical interval precedes a progressive ascending weakness this association weakens and may support an immunological mechanism. GBS after lumbar surgery is wholly unexpected and thus there are significant challenges in recognising and making the diagnosis. We report a case of fulminant GBS that progressed to loss of all motor function following elective lumbar spine surgery.

A Case Report of "Propofol Frenzy": Anesthetic Considerations for a Severe Propofol-Induced Neuroexcitation Reaction.

Propofol "frenzy" is considered a severe propofol-induced neuroexcitatory reaction involving nonepileptic spells of extremity thrashing, marked agitation, irregular eye movements, and impaired consciousness. Patients with propofol neuroexcitation present unique challenges for anesthesia providers due to underrecognition, lack of diagnostic tests, and differentiating from other comparable disorders that require medications that can exacerbate symptoms. We present a case of a healthy young patient whose postoperative course was complicated by propofol frenzy and functional limb paralysis following hip surgery with a spinal anesthetic and propofol sedation. This case highlights anesthesia considerations for propofol frenzy and discusses dexmedetomidine as a promising modality for prompt management.

Repeat Catheter Angiography in Patients with Aneurysmal-Pattern Angiographically Negative Subarachnoid Hemorrhage.

BACKGROUND: A significant proportion of patients with subarachnoid hemorrhage have a normal cerebral angiogram. Patients with angiographically negative subarachnoid hemorrhage (anSAH) with either perimesencephalic- (panSAH) or aneurysmal-pattern hemorrhage (aanSAH, also known as diffuse anSAH) have an excellent prognosis, but only if underlying vascular abnormalities are completely excluded. The rate of occult aneurysms in patients with aanSAH varies widely across studies. The purpose of this study was to quantify the value of repeat DSA in these patients. METHODS: We reviewed the records of all patients initially diagnosed with aanSAH after a screening DSA at a single tertiary neurovascular referral center from January 2006-April 2018. Patients with panSAH and traumatic SAH were excluded. We also performed a systematic review and meta-analysis of positive second DSAs in previously published case series of patients with aanSAH who underwent two serial DSAs. For meta-analysis, PubMed Central, MEDLINE and Cochrane Library databases were searched for pertinent studies up to November 2019. The rate of aneurysm detection on repeat angiography was extracted from each study. Pooled rates for positive second angiogram were calculated as untransformed proportions in a binary random-effects model meta-analysis. Inter-study heterogeneity was calculated using an I2 statistic. RESULTS: Three of 27 patients (11.1%) with aanSAH and at least two DSAs were subsequently found to have a cerebral aneurysm in our institutional dataset. Twenty-six studies in our systematic review met inclusion criteria, and the pooled rate of positive second angiogram was 10.4% (95% CI 7.3%-13.5%, P < 0.001). Substantial inter-study heterogeneity was observed in the meta-analysis (I2 = 61.7%, P < 0.001). CONCLUSIONS: One in 10 patients with aanSAH has an occult ruptured aneurysm. A second-look DSA should be strongly considered in these cases.

Subdural hematoma from an acquired dural arteriovenous fistula following external ventricular drain placement for subarachnoid hemorrhage.

Objective: Intracranial dural arteriovenous fistulas represent pathological connections between dural arteries and dural veins, dural sinuses or meningeal veins in the absence of an intervening capillary bed. They are thought to be acquired secondary to trauma, surgery, sinus thrombosis, venous hypertension or arterial dysplasia. Methods: A 66-year-old Asian female presented with subarachnoid hemorrhage secondary to ruptured 2-mm saccular aneurysm of the left middle cerebral artery associated with fusiform dilatation. It was successfully treated with endovascular coiling. A right frontal external ventricular drain was also placed to treat her hydrocephalus. On post-bleed day 10, she became acutely unresponsive with a fixed and dilated right pupil. Head CT was obtained and revealed an acute right subdural hematoma which was emergently evacuated. Results: No obvious bleeders were identified during surgery. Patient improved and repeat catheter angiography a week later showed a new dural arteriovenous fistula fed by the anterior falcine artery and the middle meningeal artery to a cortical vein draining into the superior sagittal sinus. Conclusion: We hope that the present report will raise awareness to treating physicians to be cognizant of this unusual complication in their differential diagnosis when treating patients with an EVD in place.

Treatment of Movement Disorder Emergencies in Autoimmune Encephalitis in the Neurosciences ICU.

Immune response against neuronal and glial cell surface and cytosolic antigens is an important cause of encephalitis. It may be triggered by activation of the immune system in response to an infection (para-infectious), cancer (paraneoplastic), or due to a patient's tendency toward autoimmunity. Antibodies directed toward neuronal cell surface antigens are directly pathogenic, whereas antibodies with intracellular targets may become pathogenic if the antigen is transiently exposed to the cell surface or via activation of cytotoxic T cells. Immune-mediated encephalitis is well recognized and may require intensive care due to status epilepticus, need for invasive ventilation, or dysautonomia. Patients with immune-mediated encephalitis may become critically ill and display clinically complex and challenging to treat movement disorders in over 80% of the cases (Zhang et al. in Neurocrit Care 29(2):264-272, 2018). Treatment options include immunotherapy and symptomatic agents affecting dopamine or acetylcholine neurotransmission. There has been no prior published guidance for management of these movement disorders for the intensivist. Herein, we discuss the immune-mediated encephalitis most likely to cause critical illness, clinical features and mechanisms of movement disorders and propose a management algorithm.

Variable Significance of Brain MRI Findings in Infective Endocarditis and Its Effect on Surgical Decisions.

OBJECTIVE: To determine how brain magnetic resonance imaging (MRI) findings impact clinical outcomes in patients with infective endocarditis (IE) and to propose a management algorithm for patients with neurologic symptoms who are candidates for valve surgery (VS). PATIENTS AND METHODS: Data from our center were retrospectively reviewed for patients hospitalized with IE between January 1, 2007, and December 31, 2014. Outcomes were postoperative intracerebral hemorrhage (ICH), 6-month mortality, and functional outcome at last follow-up as described by the modified Rankin Scale (mRS) score. Good outcome was defined as an mRS score of 2 or less. RESULTS: A total of 361 patients with IE were identified, including 127 patients (35%) who had MRI. One hundred twenty-six of 361 patients (35%) had neurologic symptoms, which prompted MRI in 79 of 127 patients (62%); 74 of 79 (94%) had acute or subacute MRI abnormalities. One patient with subarachnoid and multifocal ICH on MRI developed postoperative ICH. Patients with VS despite MRI abnormalities had lower 6-month mortality (odds ratio [OR], 0.17; 95% CI, 0.06-0.48; P<.001) and better functional outcome (OR, 4.43; 95% CI, 1.51-13.00; P=.005). Irrespective of VS, lobar or posterior fossa ICH on MRI was associated with 6-month mortality (OR, 3.58; 95% CI, 1.22-10.50; P=.02) and territorial ischemic stroke was inversely associated with good mRS (OR, 0.29; 95% CI, 0.13-0.66; P=.002). In neurologically asymptomatic patients who had VS, MRI findings did not impact 6-month mortality or functional outcomes. CONCLUSION: Magnetic resonance imaging detects a large number of abnormalities in patients with IE. Preoperative lobar hematoma and large territorial stroke determine outcome irrespective of VS. When indicated, VS increases the odds of a good outcome despite MRI abnormalities.

Stomaching Acute Brain Injury.

Gastrointestinal complications, including hemorrhage, can occur with intracranial lesions and after craniotomy. As early as the 19th century, surgeons were aware that brain tumors could cause gastric ulcers and acute perforations. Investigators used animal experiments both to reproduce these clinical observations and to seek ways to block the effects. Gastrointestinal lesions were seen as a result of the stress of acute brain injury or as a direct consequence of brain surgery. The thinking at the time was markedly influenced by the presumed stress and psychic factors proposed by Cannon. This historical vignette summarizes the major experimental works linking the brain with the stomach.

Characteristics of Spontaneous Spinal Cord Infarction and Proposed Diagnostic Criteria.

Importance: Spinal cord infarction (SCI) is often disabling, and the diagnosis can be challenging without an inciting event (eg, aortic surgery). Patients with a spontaneous SCI are often misdiagnosed as having transverse myelitis. Diagnostic criteria for SCI are lacking, hindering clinical care and research. Objective: To describe the characteristics of spontaneous SCI and propose diagnostic criteria. Design, Setting, and Participants: An institution-based search tool was used to identify patients evaluated at Mayo Clinic, Rochester, Minnesota, from January 1997 to December 2017 with a spontaneous SCI. Patients provided written consent to use their records for research. Participants were 18 years and older with a diagnosis of spontaneous SCI (n = 133), and controls were selected from a database of alternative myelopathy etiologies for validation of the proposed diagnostic criteria (n = 280). Main Outcomes and Measures: A descriptive analysis of SCI was performed and used to propose diagnostic criteria, and the criteria were validated. Results: Of 133 included patients with a spontaneous SCI, the median (interquartile range) age at presentation was 60 (52-69) years, and 101 (76%) had vascular risk factors. Rapid onset of severe deficits reaching nadir within 12 hours was typical (102 [77%]); some had a stuttering decline (31 [23%]). Sensory loss occurred in 126 patients (95%), selectively affecting pain/temperature in 49 (39%). Initial magnetic resonance imaging (MRI) spine results were normal in 30 patients (24%). Characteristic MRI T2-hyperintense patterns included owl eyes (82 [65%]) and pencil-like hyperintensity (50 [40%]); gadolinium enhancement (37 of 96 [39%]) was often linear and located in the anterior gray matter. Confirmatory MRI findings included diffusion-weighted imaging/apparent diffusion coefficient restriction (19 of 29 [67%]), adjacent dissection/occlusion (16 of 82 [20%]), and vertebral body infarction (11 [9%]). Cerebrospinal fluid showed mild inflammation in 7 of 89 patients (8%). Diagnostic criteria was proposed for definite, probable, and possible SCI of periprocedural and spontaneous onset. In the validation cohort (n = 280), 9 patients (3%) met criteria for possible SCI, and none met criteria for probable SCI. Conclusions and Relevance: This large series of spontaneous SCIs provides clinical, laboratory, and MRI clues to SCI diagnosis. The diagnostic criteria proposed here will aid clinicians in making the correct diagnosis and ideally improve future care for patients with SCI. The validation of these criteria supports their utility in the evaluation of acute myelopathy.

Clinical factors associated with Guillain-Barré syndrome following surgery.

BACKGROUND: We sought to identify clinical associations and potential triggers of Guillain-Barré syndrome (GBS) within 6 weeks of surgery. METHODS: We retrospectively reviewed consecutive patients diagnosed with GBS within 6 weeks of a surgery between January 1995 and June 2014 at Mayo Clinic. Postsurgical GBS was defined as symptom onset within 6 weeks of surgery. Patients with postsurgical GBS were compared with patients who did not have a surgery prior to GBS onset to determine differences between groups. RESULTS: A total of 208 patients with GBS, median age 55 years (interquartile range [IQR] 41-68), were included. Nineteen patients (9.1%) developed postsurgical GBS. Median duration from the surgery to onset of first GBS symptom was 15 days (IQR 9-37). The main types of surgeries preceding GBS were gastrointestinal, orthopedic, and cardiac. General anesthesia was used in 18 (95%) and conscious sedation in 1 (5%) patient. Among the 19 patients with postsurgical GBS, 11 (57.9%) had a known diagnosis of malignancy. Autoimmune conditions were present in 5 (26.3%) patients. Postoperative infection was found in 4 (21%) patients. On univariate analysis, the factors that showed an association with postsurgical GBS were age (p = 0.02), malignancy (p ≤ 0.0004), active malignancy (p = 0.03), preexisting autoimmune disorder (p = 0.02), and infection (p = 0.0001). On multivariate analysis, only active malignancy (0.03) remained associated. CONCLUSIONS: Surgery antedated GBS in 9.1% of patients. Postsurgical GBS was more common in patients with an active malignancy. A prospective study is needed to determine whether active malignancy represents an independent risk factor for the development of postsurgical GBS.

Comparison of Ocular Ultrasonography and Magnetic Resonance Imaging for Detection of Increased Intracranial Pressure.

BACKGROUND/AIMS: To evaluate and compare the performance of ocular ultrasonography (US) and magnetic resonance imaging (MRI) for detecting increased intracranial pressure (ICP) in patients with idiopathic intracranial hypertension (IIH). METHODS: Twenty-two patients with papilledema from IIH and 22 with pseudopapilledema were prospectively recruited based on funduscopic and clinical findings. Measurements of optic nerve sheath diameters (ONSDs) 3 mm behind the inner sclera were performed on B-scan US and axial T2-weighted MRI examinations. Pituitary-to-sella height ratio (pit/sella) was also calculated from sagittal T1-weighted MRI images. Lumbar puncture was performed in all patients with IIH and in five patients with pseudopapilledema. RESULTS: Average US and MRI ONSD were 4.4 (SD ± 0.7) and 5.2 ± 1.4 mm for the pseudopapilledema group and 5.2 ± 0.6 and 7.2 ± 1.6 mm for the papilledema group (p < 0.001). Average MRI pit/sella ratio was 0.7 ± 0.3 for the pseudopapilledema group and 0.3 ± 0.2 for the papilledema group (p < 0.001). Based on receiver-operator curve analysis, the optimal thresholds for detecting papilledema are US ONSD > 4.8 mm, MRI ONSD > 6.0 mm, and MRI pit/sella < 0.5. Combining a dilated US ONSD or MRI ONSD with a below-threshold MRI pit/sella ratio yielded a sensitivity of 73% and specificity of 96% for detecting IIH. Adding the US ONSD to the MRI ONSD and pit/sella ratio only increased the sensitivity by 5% and did not change specificity. CONCLUSION: US and MRI provide measurements of ONSD that are well-correlated and sensitive markers for increased ICP. The combination of the ONSD and the pit/sella ratio can increase specificity for the diagnosis of IIH.

Spinal cord infarction: Clinical and imaging insights from the periprocedural setting.

OBJECTIVE: Describe the range of procedures associated with spinal cord infarction (SCI) as a complication of a medical/surgical procedure and define clinical and imaging characteristics that could be applied to help diagnose spontaneous SCI, where the diagnosis is often less secure. METHODS: We used an institution-based search tool to identify patients evaluated at Mayo Clinic, Rochester, MN from 1997 to 2016 with a periprocedural SCI. We performed a descriptive analysis of clinical features, MRI and other laboratory findings, and outcome. RESULTS: Seventy-five patients were identified with SCI related to an invasive or non-invasive surgery including: aortic aneurysm repair (49%); other aortic surgery (15%); and a variety of other procedures (e.g., cardiac surgery, spinal decompression, epidural injection, angiography, nerve block, embolization, other vascular surgery, thoracic surgery) (36%). Deficits were severe (66% para/quadriplegia) and maximal at first post-procedural evaluation in 61 patients (81%). Impaired dorsal column function was common on initial examination. Imaging features included classic findings of owl eyes or anterior pencil sign on MRI (70%), but several other T2-hyperintensity patterns were also seen. Gadolinium enhancement of the SCI and/or cauda equina was also common when assessed. Six patients (10%) had an initial normal MRI despite a severe deficit. CONCLUSIONS: Procedures associated with SCI are many, and this complication does not exclusively occur following aortic surgery. The clinical and radiologic findings that we describe with periprocedural SCI may be used in future studies to help distinguish spontaneous SCI from alternate causes of acute myelopathy.

On Aneurysmal Rupture and Rerupture.

A warning leak is a curious phenomenon attributed to cerebral aneurysms. Once the leak occurs, it has been postulated it could lead to a more catastrophic rebleeding. The designation "warning leak" trickled into neurosurgery vocabulary as early as the 1950s. The phenomenon has been poorly understood and characterized, but its presence spurs emergency physicians and neurointensivists to take action to secure the aneurysm. Rapid treatment of a recently discovered aneurysm is now commonplace, but it has not always been so. Antifibrinolytic agents spawned particular interest in the late 1970s, when many neurosurgeons postponed surgery after a recent hemorrhage. This historical vignette reviews the early views on aneurysmal rupture, rerupture, and the role of fibrinolysis.