Patients may present to the ED with new onset weakness due to myasthenia gravis (MG). A group that is frequently missed is late-onset MG, which occurs after the age of 50. It is frequently misdiagnosed as a stroke or transient ischemic attach (TIA).
Two cardinal features:
Bonus pearl: Ocular symptoms are present in up to 85% of patients with MG, with unilateral ptosis or asymmetric bilateral ptosis being the most common presentations.
Impact of an ED pharmacist on time to thrombolysis in acute ischemic stroke
Patient found pulseless after submersion in water for 20 minutes. After ROSC, patient’s GCS was 3 and pupils are dilated and nonreactive.
Magnetic resonance imaging (MRI) is the method of choice for imaging the spine for the suspicion of non-traumatic disorder, such as multiple sclerosis (MS), transverse myelitis, epidural abscess, spinal cord infarcts, and spondylotic myelopathy (changes in the spinal cord due to disk herniation or osteophytes in degenerative joint disease).
If the differential diagnosis includes infection, neoplasm, demyelination or inflammation, then IV contrast should be administered.
Updated Guidelines for Traumatic Brain Injury
The Brain Trauma Foundation (BTF) Guidelines for the Management of Severe Traumatic Brian Injury (TBI) was recently updated and published in September 2016.
Updated recommendations include:
For the executive summary and complete guidelines, go to https://braintrauma.org/guidelines/guidelines-for-the-management-of-severe-tbi-4th-ed#/
You have a patient in whom you suspect meningitis, but he is on warfarin for a history of pulmonary embolism. You started empirical antibiotics. His INR is 2.6, and you want to do a lumbar puncture (LP) to confirm your diagnosis. Can you use Prothrombin Complex Concentrate to lower his INR and safely perform the LP?
Take Home Point:
Using PCC to lower INR to enable LP is relatively safe and effective in patients on vitamin K antagonists. The dose used was individually determined by the physician according to initial INR.
Limitation:
This is a retrospective study, with no control group. One patient (2.7%) had a myocardial infarction that was “possibly related” to the PCC administration.
Ataxia is an important clinical sign of cerebellar pathology, but how is it actually described?
Stance ataxia: inability to stand with feet together for more than 30 seconds
Gait ataxia
Sensory ataxia: the first 2 elements, in addition to a positive Romberg sign
Truncal ataxia: oscillation of body while sitting or standing
Limb ataxia: functional impairment in performing actions such as writing or buttoning and improves with slowing down the movement
Dysdiadokinesia: impairment of rapidly alternating movement
Intention tremor: tested by finger-to-nose and heel-to-shin.
Dysmetria: pastpointing or undershooting on finger-chasing or shin-tap.
Dysarthria: irregular and slow speech with unnecessary hesitation
Nystagmus and other ocular disturbances, such as ocular flutter and opsoclonus.
The first 3 are present in both cerebellar pathology and loss of proprioceptive input, the rest are usually due to cerebellar pathology or ataxic syndrome.
Bottom Line: Additional assessment of gaze deviation, aphasia and neglect, as included in the FAST-ED scale, increases the accuracy of predicting LVOS.
Multiple sclerosis (MS) relapses are defined as new or worsening neurologic deficits lasting 24 hours or more in the absence of fever or infection. Symptoms may be visual, motor, sensory, balance or cognitive. It is a clinical diagnosis, but the presence of a new gadolinium-enhancing lesion on MRI can be used as a radiologic marker of an MS relapse. However, it is unclear whether asymptomatic lesions should be treated, making it prudent to rely on the clinical evaluation rather than the MRI for diagnosis.
Moderate to severe relapses should be treated within 1 week of onset. The mainstay of treatment for relapses is IV methylprednisolone, usually dosed at 500mg to 1g per day for 3-7 days.
Similar symptoms occurring in the presence of fever, heat exposure, stress or infection (such as urinary or upper respiratory tract infections) are "pseudoexacerbations", and should not be treated as an MS relapse.
The PATCH trail, recently published in the Lancet, looked at whether giving platelets to patients, that were on anti-platelet therapy (e.g.: aspirin, clopedrigrel, or dipyridamole) for at least 7 days at the time of their spontaneous intracerebral hemorrhage, improved neurologic outcomes and mortality.
This was a large (60 hospitals) multicener, open-label, masked endpoint, randomized trial that enrolled a total of 190 patients (97 platelet transfusion and 93 standard care).
The outcomes were surprising. Patient in the Platelet group had a higher rat of death or dependence at 3 months (Adjusted OR 2.05; 95% CI 1.18 3.56; p = 0.0114).
The authors concluded "Platelet transfusion seems inferior to standard care for people taking anti-platelet therapy before a spontaneous intracerebral hemorrhage"
Though this is the first study to look at this, the studies design and outcomes should really make use reconsider whether we give these patients platelets. The thought is that ICB or hemorrhagic strokes also have a component of ischemic stroke and a watershed area that's blood flow becomes compromised with the platelet transfusion.
TAKE HOME POINT: We should not routinely transfuse platelets in our patients that were on antiplatelet therapy prior to their ICB.
Gadolinium - To Use or Not Use?
| Non-Contrast MRA/MRV | Contrast-Enhanced MRA/MRV | |
| How Does It Work? | * Time-of-flight (TOF) is a commonly used sequence * Relies on flow of blood into imaging plane * Difference between signal of blood and suppressed background tissue | * Similar to CT angiography/venography * Higher intravascular signal purely from gadolinium-based contrast, not dependent on flow
|
| Pros | * Does not require contrast
| * Generally better image quality * Shorter acquisition time |
| Cons | * Slow, turbulent, or retrograde flow may result in signal loss * Over-estimates stenosis * Longer acquisition time | * RIsks associated with contrast use * Timing of image acquisition important |
| Applications | * Patients with allergy to gadolinium, renal dysfunction, pregnancy * Evaluation of intracranial vessels and cerebral venous system | * Evaluation of stenoses and occlusions of the neck vessels and their origins at the aortic arch
|
Short Answer: No
Classically, some therapies for headaches are thought to be effective in only certain classifications of headaches, such as triptans in migraines, or oxygen in cluster headaches. This is not necessarily true.
Triptans have been successfully used in cluster headaches, as found in the 2013 Cochrane review.1
More recently, "high-flow" oxygen (referring to 12 L/min of oxygen, delivered through a facemask) has been studied in migraine headaches, with promising results. When compared with placebo (air), oxygen used for 15 minutes was more effective in pain relief and improving visual symptom, with no significant adverse events. 2
Want to learn more about how to read a brain MRI? Here are the basics:
Stay tuned for more pearls in this series on brain MRI!
