Protracted respiratory failure in a case of global spinal syringomyelia and Chiari malformation following administration of diazepam: illustrative case.

BACKGROUND: Syringomyelia is defined as dilation of the spinal cord's central canal and is often precipitated by skull base herniation disorders. Although respiratory failure (RF) can be associated with skull base abnormalities due to brainstem compression, most cases occur in pediatric patients and quickly resolve. The authors report the case of an adult patient with global spinal syringomyelia and Chiari malformation who developed refractory RF after routine administration of diazepam. OBSERVATIONS: A 31-year-old female presented with malnutrition, a 1-month history of right-sided weakness, and normal respiratory dynamics. After administration of diazepam prior to magnetic resonance imaging (MRI), she suddenly developed hypercapnic RF followed MRI and required intubation. MRI disclosed a Chiari malformation type I and syrinx extending from C1 to the conus medullaris. After decompressive surgery, her respiratory function progressively returned to baseline status, although 22 months after initial benzodiazepine administration, the patient continues to require nocturnal ventilation. LESSONS: Administration of central nervous system depressants should be closely monitored in patients with extensive syrinx formation given the potential to exacerbate diminished central respiratory drive. Early identification of syrinx in the context of Chiari malformation and hemiplegia should prompt clinical suspicion of underlying respiratory compromise and early involvement of intensive care consultants.

Peripheral Insertion of Pediatric Central Venous Catheters in Adults with Difficult I.V. Access.

BACKGROUND: Difficult intravenous access is a frequent occurrence in critical care and emergency medicine. Prior intravenous access, chemotherapy use, and obesity are a few factors associated with difficult access. Alternatives to peripheral access are often contraindicated, not feasible, or not readily available. OBJECTIVES: To describe the feasibility and safety of peripheral insertion of peripherally inserted pediatric central venous catheters (PIPCVC) in a cohort of adult critical care patients with difficult intravenous access. METHODS: Prospective observational study of adult patients with difficult intravenous access who underwent peripheral insertion of pediatric PIPCVCs at a large university hospital. RESULTS: During a 1-year period, 46 patients were evaluated for PIPCVC; 40 catheters were placed successfully. The median age of the patients was 59 years (range 19-95 years) and 20 (50%) were female. The median body mass index was 27.2 (range 17.1-41.8). The basilic vein was accessed in 25/40 (63%) patients, the cephalic in 10/40 (25%), and the accessed vessel was missing in 5/40 (13%) cases. The PIPCVCs were in place for a median of 8 days (range 1-32). One superficial thrombosis and one deep occurred; pulmonary embolism did not occur. CONCLUSIONS: PIPCVC placement seems to be a feasible option in patients in whom peripheral intravenous access is difficult. The safety of this technique needs to be evaluated in prospective studies.

Military Soft Skills Applicable to the ICU.

To describe how soft skills acquired during military service can be applied to the practice of critical care medicine. DATA SOURCES: A systematic search was performed in PubMed. STUDY SELECTION: We selected all studies that addressed soft skills in medicine. DATA EXTRACTION: Information present in published articles was analyzed by the authors and incorporated in the article if relevant to the practice of critical care medicine. DATA SYNTHESIS: Integrative review of 15 articles combined with the authors' clinical experience practicing military medicine in country and overseas while also practicing academic intensive care medicine. CONCLUSIONS: Soft skills used in the military have potential applications to modern intensive care medicine. Teaching soft skills in parallel with the technical aspects of intensive care medicine should be an integral part of critical care fellowships.

Reports of Guillain-Barre Syndrome Following COVID-19 Vaccination in the USA: An Analysis of the VAERS Database.

BACKGROUND AND PURPOSE: An association between Guillain-Barre syndrome and its variants (GBS/V) and vaccines has led to hesitancy toward vaccination. COVID-19 vaccines could theoretically provoke GBS/V via immune activation. We analyzed reports of GBS/V after COVID-19 vaccination in the vaccine adverse event reporting system (VAERS). METHODS: The VAERS database is a surveillance system used to report vaccination events in the USA, and is open for consumers and physicians to access. It was queried for reports of GBS/V following COVID-19 vaccination. Reports were reviewed by four neurologists. Modified diagnostic criteria were used to classify reports into definite, possible, and not GBS/V or insufficient data. Descriptive statistics were used to describe the sample, chi-square tests and one-way ANOVAs were used to compare intergroup differences, and t-test were used to compare group means. RESULTS: In 2021, 815 reports of GBS/V were filed. The completion rate for the variables in VAERS was 93.5%. The median age was 55 years (interquartile range [IQR]=5-86 years) and 50% of the subjects were male. The median time of onset was 10 days (IQR=0-298 days), 11% reported onset on the day of vaccination, and 13% reported onset after 6 weeks. Hospitalization was reported by 77%, with a median stay of 7 days (IQR=1-150 days). Lack of recovery, permanent disability, and death constituted 57%, 46%, and 2% of the reports, respectively. Based on GBS/V criteria, 47% of the cases were definite, 16% were possible, and 37% were not GBS/V or insufficient data. An alternate diagnosis was provided in 9% of cases. CONCLUSIONS: GBS/V reports following COVID-19 vaccination were common, but many occurred outside of the expected timelines for GBS/V. Only 47% of cases represented definite GBS/V.

Traumatic Optic Neuropathy: The Forgotten Concussion.

Cerebral concussions are a well-recognized issue in military and civilian practice. Although most physicians are well versed in recognizing concussion symptoms, many are not as adept at diagnosing and managing comorbid traumatic optic neuropathy (TON). Traumatic optic neuropathy typically follows cerebral concussions but is often not diagnosed as its symptoms are attributed to brain injury or the presence of altered consciousness impedes its recognition. We hereby describe a soldier who sustained a cerebral concussion with an associated unrecognized TON. We review the epidemiology, pathophysiology, diagnosis, and management of TON.

Use of Helicopter Medical Transportation to the Neuroscience Intensive Care Unit.

BACKGROUND: Helicopter medical transportation (HMT) is a valuable resource that can expedite medical care by shortening transferring times. However, there is conflicting evidence regarding its cost and efficacy. No specific studies have addressed its use in patients transferred to the neuroscience intensive care unit (NSICU). METHODS: This was a retrospective study performed at a university hospital in the coastal southeastern USA. The flight logs for the air ambulance company were reviewed, and all patients undergoing HMT to the NSICU during a 1-year period were identified. Flight logs and medical records were reviewed to obtain basic demographics, diagnosis, mortality, transportation distance, and performance of time-sensitive interventions (TSIs) to include ventriculostomy placement, emergency craniotomy, emergency craniectomy, emergency aneurysm obliteration, emergency spine surgery, emergent endovascular procedures, subdural drain placement, emergent shunt revision, and continuous electroencephalography (EEG) performed within 4 h of admission. We analyzed the cost of HMT and correlated the clinical variables with the performance of TSIs. RESULTS: A total of 101 patients underwent HMT during a 12-month period; 26 underwent 30 TSIs (4 underwent 2 TSIs) and an additional 4 were transported for EEG monitoring. The only clinical variable associated with a TSI was subarachnoid hemorrhage with ventriculostomy placement. Continuous EEG monitoring performed in four patients with suspected status epilepticus did not show status epilepticus in any of them (one was performed after 4 h). Transportation distance was less than 60 miles in four patients who underwent TSIs. The total cost of HMT was $3,360,573: $842,672 for those who underwent TSIs and $2,517,901 for those who did not. When compared with ground transportation, an excess cost of $3,129,415.25 was incurred by using HMT. There was no difference in the median cost of transportation between patients who underwent TSIs and those who did not ($30,210 vs. $30,211). The median cost transportation difference between HMT and ground transportation was significantly different (p < 0.001), with a median excess cost of $28,023 (range $15,553-76,155) per patient. CONCLUSIONS: The majority of patients who were transferred via HMT did not undergo TSIs, and among those who underwent TSIs, approximately one in six was transported from a hospital located less than 60 miles away from the NSICU; the distances of ground and air transportation are equivalent. Helicopter transfers may play a role in subarachnoid hemorrhage management. A significant expense was incurred by using HMT for the majority of patients (75%) who did not undergo TSIs.

Perception of Provision of Futile Care Among Clinicians in the Neuroscience Intensive Care Unit.

BACKGROUND: Futile care in the neuroscience intensive care unit (NSICU) can create moral distress for clinicians who may differ in their interpretation of the value of such care. We sought to compare the perception of provision of futile care in the NSICU among physicians, advanced practice providers, and intensive care unit registered nurses (ICURNs). METHODS: This is a cross-sectional study of 77 patients. A standardized questionnaire was used to ask clinicians whether care being provided to NSICU patients admitted for more than 48 hours was futile and whether they would want that treatment for their loved one. Demographics, diagnosis, and reason for treatment futility were collected. Futility was analyzed independently and in an aggregate manner (yes/probable combined and no/probable combined). RESULTS: The sample median age was 61 (SD, 17.179) years, men comprised 53% of the sample, and 68% were white. Collectively, there were 77 futile responses (33%), 136 nonfutile (59%), and 18 probable futile (8%). Physicians and nurse practitioners deemed futility in 36% of patients; ICURNs, in 27% (P < .05). Age, race, or diagnosis did not impact futility perception. The treatment was acceptable for a loved one in 53% of cases for physicians, 43% for advanced practice providers, and 48% for ICURNs (P < .05). Interobserver agreement for futility was 0.469 (CK), and pairwise agreement was 71%. Interobserver agreement for treatment acceptable for a loved one was 0.568 (CK), and pairwise agreement was 78%. CONCLUSIONS: Clinicians consider NSICU care futile in one-third of patients, but correlation among them is moderate; no specific variable is associated with such perception.

Tactical Neurocritical Care.

Neurocritical care is usually practiced in the comfort of an intensive care unit within a tertiary care medical center. Physicians deployed to the frontline with the US military or allied military are required to use their critical care skills and their neurocritical skills in austere environments with limited resources. Due to these factors, tactical critical care and tactical neurocritical care differ significantly from traditional critical care. Operational constraints, the tactical environment, and resource availability dictate that tactical neurocritical care be practiced within a well-defined, mission-constrained framework. Although limited interventions can be performed in austere conditions, they can significantly impact patient outcome. This review focuses on the US Army approach to the patient requiring tactical neurocritical care specifically point of injury care and care during transportation to a higher level of care.

Critical Care Management of Anti-N-Methyl-D-Aspartate Receptor Encephalitis.

OBJECTIVES: Anti-N-methyl-D-aspartate receptor encephalitis is considered an immune-mediated form of encephalitis with paraneoplastic and nonparaneoplastic forms. Delay in recognition is common and patients typically present to the ICU without a diagnosis or with complications following a delayed diagnosis. The aim of this review is to provide a focused overview for the ICU clinician regarding presentation, diagnosis, and critical care management. DATA SOURCES, STUDY SELECTION, AND DATA EXTRACTION: PubMed database search with manual review of articles involving anti-N-methyl-D-aspartate receptor encephalitis. DATA SYNTHESIS: Anti-N-methyl-D-aspartate receptor encephalitis is increasingly encountered in the ICU. The cascade of events initiating anti-N-methyl-D-aspartate receptor antibody formation may involve an infectious trigger particularly in the setting of teratoma. Following a prodrome, most patients develop psychiatric symptoms followed by movement disorder. Classical, psychiatric, and catatonic phenotypes may be distinguished based on the presence and severity of symptoms. Early immunotherapy and low initial cerebrospinal fluid inflammation are independent predictors of positive outcomes in ICU patients. Concomitant organ failure, status epilepticus, and the identification of a tumor did not influence outcome in critically ill patients. Supportive care in the ICU includes management of various manifestations of dyskinesia, status epilepticus, autonomic disorders, and the need for general sedation. Common treatment strategies and limitations are discussed including the emerging role of bortezomib. CONCLUSIONS: Intensivists should be familiar with the presentation and management of anti-N-methyl-D-aspartate receptor encephalitis. Early diagnosis and immediate implementation of steroids, immunoglobulins, and/or plasmapheresis and immune therapy are associated with a good neurologic outcome although response may be delayed. The selection and timing of second-line immune therapy requires further study.

Helmet-Induced Occipital Neuralgia in a Military Aviator.

BACKGROUND: Headaches among military personnel are very common and headgear wear is a frequently identified culprit. Helmet wear may cause migrainous headaches, external compression headache, other primary cranial neuralgias, and occipital neuralgia. The clinical features and the response to treatment allow distinction between the different types of headaches. Headaches among aviators are particularly concerning as they may act as distractors while flying and the treatment options are often incompatible with flying status. CASE REPORT: A 24-yr-old door gunner presented with suboccipital pain associated with the wear of his helmet. He described the pain as a paroxysmal stabbing sensation coming in waves. The physical exam and history supported the diagnosis of primary occipital neuralgia. Systemic pharmacological options were discussed with the soldier, but rejected due to his need to remain in flying status. An occipital nerve block was performed with good clinical results, supporting the diagnosis of occipital neuralgia and allowing him to continue as mission qualified. DISCUSSION: Occipital neuralgia can be induced by helmet wear in military personnel. Occipital nerve block can be performed in the deployed setting, allowing the service member to remain mission capable and sparing him/her from systemic side effects.Chalela JA. Helmet-induced occipital neuralgia in a military aviator. Aerosp Med Hum Perform. 2018; 89(4):409-410.

New Onset Migraine Associated With a Civilian Burn Pit.

BACKGROUND: Deployed service members exposed to burn pit smoke can experience a multitude of symptoms. Respiratory symptoms after burn pit smoke exposure are well recognized, but neurologic symptoms are less well recognized. There are reports of migraines triggered by odors but no specific reports of new onset migraines triggered by exposure to burn pit smoke. Clinicians encountering patients with new onset migraines in the deployed setting face the dilemma of evacuating the patients to perform neuroimaging or keeping them in theatre. METHODS: Retrospective case series study and review of the literature. FINDINGS: Three patients with new onset headache after exposure to open burn pit smoke are described. The headaches met established criteria to be classified as migraine with aura in two patients and migraine without aura in one patient. The migraines were triggered by exposure to the burn pit smoke and relieved by avoidance of the smoke. The patients did not have history of migraine and had normal neurological examinations. Computed tomography performed in one patient and optic nerve insonation performed in all three patients were normal. The patients responded well to triptans and antiemetic medicines. DISCUSSION: Nociceptive odors can trigger classic migraines in adults without prior history of migraine. The temporal association between exposure to the odor and the development of the headache, the absence of abnormalities on neurologic examination, and the response to triptans help establish the diagnosis. Activation of the trigeminal system leading to release of pain-related neuropeptides may mediate the migrainous symptoms. Evacuation for advanced neuroimaging or specialized consultation can be avoided if the above-mentioned criteria are met.

Blood Pressure Guideline Adherence in Patients with Ischemic and Hemorrhagic Stroke in the Neurointensive Care Unit Setting.

BACKGROUND AND PURPOSE: Patients with acute brain injuries require strict physiologic control to minimize morbidity and mortality. This study aimed to assess in-hospital compliance to strict physiologic parameters (BP, HR, ICP, SpO2) in these populations. METHODS: Patients with severe cerebrovascular events were admitted to the neurointensive care unit (NSICU) and were continuously monitored using the BedMasterEX (Excel Medical Electronics Inc, FL) system, which recorded hemodynamic data via an arterial catheter continuously in 5-s intervals. Furthermore, we investigated the impact of healthcare provider shift changes (6-8 a.m./p.m) and of day (6 a.m.-6 p.m.) versus night (6 p.m-6 a.m) shifts in hemodynamic control. RESULTS: Fifty patients admitted to the NSICU, 50 % male, mean age 59.7 ± 13.9 years with subarachnoid hemorrhage (23), ischemic stroke (8), subdural hematoma (4), intracerebral hemorrhage (3), intraventricular hemorrhage (2), and miscellaneous injuries (10) were enrolled. Data represented 2,337 total hours of continuous monitoring. Systolic BPs (SBP) were on average outside of recommended ranges 32.26 ± 30.46 % of the monitoring period. We subdivided adherence to ideal SBP range: optimal (≥99 % of time spent in NSICU within range) was achieved in 12 %, adequate (90 %) in 16 %, suboptimal (80 %) in 20 %, inadequate I (70 %) in 12 %, and inadequate II (<70 %) in 40 % of patients. Comparison of shift change %time and day versus night %time out of parameter yielded no statistically significant differences across SAH patients. CONCLUSION: Hemodynamic management of patients with cerebrovascular injuries, based on targeted thresholds in the NSICU, yielded optimal control of SBP in only 28 % of our patients (within parameters ≥90 % of time).

Significance of Parenchymal Brain Damage in Patients with Critical Illness.

BACKGROUND: To determine the prevalence, type, and significance of brain damage in critically ill patients with a primary non-neurological diagnosis developing acute brain dysfunction. METHODS: This retrospective cohort study was performed at the Johns Hopkins University School of Medicine, an academic tertiary care hospital. Medical records were reviewed of 479 consecutive ICU patients who underwent brain magnetic resonance imaging (MRI) over a 2-year period. Patients were selected for analysis if MRI was obtained to evaluate an acute onset of brain dysfunction (altered mental status, seizures, and/or focal neurological deficit). Subjects with a history of a central nervous system disorder were excluded. The principal clinical endpoint was Glasgow Outcome Scale (GOS) assessed at discharge. MRI-defined brain abnormalities were classified according to type and location. Factors associated with MRI-defined abnormalities were assessed in uni- and multivariable models. RESULTS: 146 patients met inclusion criteria (mean age 54 ± 7 years). Brain damage was detected in 130 patients (89%). The most prevalent lesions were white matter hyperintensities (104/146, 71%) and acute cerebral infarcts (59/146, 40%). In a multivariable model, lesions on brain MRI were independently associated with unfavorable outcome (GOS1-3 in 71% of patients with lesions vs. 44% in those without, p = 0.007). No adverse events occurred in relation to transport and MRI scanning. CONCLUSIONS: In critically ill patients without known neurological disease who have acute brain dysfunction, MRI reveals an unexpectedly high burden of underlying brain damage, which is associated with unfavorable outcome. The results indicate that brain damage could be an important and under-recognized factor contributing to critical illness brain dysfunction.

Guillain-Barre variant in the deployed setting.

Guillain-Barre syndrome (GBS) is a pleomorphic condition with multiple clinical presentations. Atypical presentations may elude diagnosis particularly in the deployed setting or austere environment where diagnostic resources are limited. I describe a soldier who developed an unusual GBS variant while deployed to Iraq. Diagnosing and treating GBS in the deployed setting or in a rural, austere environment is challenging, but there are clinical guidelines that can help determine who can be treated locally and who needs evacuation. Recognizing the natural course of the disease and being able to prognosticate progression of the disease is crucial in deployed settings/austere environments. The diagnostic and therapeutic approach to GBS in the deployed setting and potential criteria for theater evacuation are reviewed.

The white cerebellum sign: an under recognized sign of increased intracranial pressure.

BACKGROUND: The "white cerebellum" sign is a rare imaging finding described mainly in children with hypoxic brain injury. MATERIALS AND METHODS: Single case report and review of the literature. FINDINGS: We describe a child with acute bacterial meningitis in whom plain CT and MRI showed the white cerebellum sign. The subtle imagings findings were not recognized and a lumbar puncture was performed. Markedly increased intracranial pressure was documented by lumbar puncture and by placement of an intraparenchymal monitor. Contrary to most prior descriptions the patient made a very good recovery. CONCLUSIONS: The white cerebellum sign is a subtle imaging finding seen in patients with diffuse cerebral edema, such finding may not be as ominous as previously thought.

Perimesencephalic subarachnoid hemorrhage triggered by hypoxic training during swimming.

INTRODUCTION: Perimesencephalic subarachnoid hemorrhage is a rare neurologic condition of unclear etiology. Multiple mechanisms have been postulated as potential triggers, but none are universally accepted. METHODS: Single observational case report and review of the literature. RESULTS: We describe a patient who developed perimesencephalic subarachnoid hemorrhage in the setting of "hypoxic training" (breath-holding while swimming). We describe the plausible pathophysiologic events that caused the hemorrhage. CONCLUSION: The occurrence of perimesencephalic subarachnoid hemorrhage during hypoxic training suggests that acute venous congestion may be a triggering factor. The increasing popularity of hypoxic training demands vigilance from health care providers.

Medical management of hunger strikers.

Hunger strikes are not infrequent occurrences in military and civilian prisons. Although practicing clinicians are familiar with the management of patients who have limited oral intake, managing hunger strikers is unfamiliar to most. The psychological, physiological, and social events that surround hunger strikes are very complex and need to be understood by those caring for hunger strike patients. To provide adequate medical care to hunger strike patients, clinicians most understand the physiological events that ensue after prolonged starvation. Careful vigilance for development of refeeding syndrome is of key importance. A multidisciplinary approach to hunger strikes is of utmost importance, and involvement of a multidisciplinary clinical team as well as prison officials is essential.

Chemical terrorism for the intensivist.

The use of chemical agents for terrorist attacks or military warfare is a major concern at the present time. Chemical agents can cause significant morbidity, are relatively inexpensive, and are easy to store and use. Weaponization of chemical agents is only limited by the physicochemical properties of some agents. Recent incidents involving toxic industrial chemicals and chemical terrorist attacks indicate that critical care services are frequently utilized. For obvious reasons, the critical care literature on chemical terrorism is scarce. This article reviews the clinical aspects of diagnosing and treating victims of chemical terrorism while emphasizing the critical care management. The intensivist needs to be familiar with the chemical agents that could be used in a terrorist attack. The military classification divides agents into lung agents, blood agents, vesicants, and nerve agents. Supportive critical care is the cornerstone of treatment for most casualties, and dramatic recovery can occur in many cases. Specific antidotes are available for some agents, but even without the antidote, aggressive intensive care support can lead to favorable outcome in many cases. Critical care and emergency services can be overwhelmed by a terrorist attack as many exposed but not ill will seek care.