POTD: Idiopathic Intracranial Hypertension

POTD: Idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH) aka pseudotumor cerebri and benign intracranial hypertension

·      rare condition

·      presents with gradual onset and chronic headache, vision changes, nausea, vomiting, and tinnitus

·      + papilledema/ swelling of the optic disc on fundoscopy

·      optic sonography

• ONSDs should be measured 3 mm behind the papilla, an average of less than 5 mm is considered normal.

• ONSD > 5 mm has been shown to be 90% sensitive and 85% specific for ICP > 20.

·      Classic presentation: young, obese female

·      + association has been found with this diagnosis and the use of oral contraceptive medications, tetracycline, anabolic steroids, and vitamin A

·      Pathophysiology is not well understood but thought to be caused by an imbalance in CSF production and reabsorption

·      Diagnostic criteria include an alert patient with either a normal neurologic examination or findings consistent with papilledema, visual field defect, or an enlarged blind spot

·      Definitive dx: Lumbar puncture

• done in a recumbent position reveals an elevated CSF opening pressure of more than 20 mm Hg in an obese patient (normal being up less than 20 mm Hg).

• normal CSF analysis.

·      CT head may show “slit like” or normal ventricles without mass effect

·      DDx: glaucoma, venous sinus thrombosis, ICH, IC mass.

·      Treatment

• Repeat LPs  

• Acetazolamide

• Surgical shunt if severe and refractory

• offending agents such as oral contraceptive medications should be discontinued.

·      Permanent loss of vision can occur in up to 10% of patients, and higher if left untreated

Sources:

• Dubourg J, Javouhey E, Geeraerts T, Messerer M, Kassai B. Ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure: a systematic review and meta-analysis. Intensive Care Med. 2011;37(7):1059-68. [pubmed]

• Blaivas M, Theodoro D, Sierzenski PR. Elevated intracranial pressure detected by bedside emergency ultrasonography of the optic nerve sheath. Acad Emerg Med. 2003;10(4):376-81. [PDF]

• https://www.ultrasoundoftheweek.com/uotw-5-answer/

• Peer IX

POTD: TB in the ED

Approach to TB in the ED.

TB might be more common than you think: In NY alone, in 2016, 3.9 cases per 100,000 people, 761 cases in NY in 2016.

Reactivation TB is about 90% of active TB in the United States. 

Who is at high risk?

Those with no “usual source of care”

• ethnic minorities

• foreign born

• HIV patient

• drug users

• nursing home patients

• homeless patients

• prisoners

Why is it often missed?

Non-specific presentation of TB

• Cough present: 64%

• Cough was chief complaint: 20%

• Only 36% had respiratory complaint at triage

What to do if for high suspicion of TB:

• Negative pressure isolation room

• N95 fitted masks

• CXR and rapid HIV

  • Why HIV test?

    • HIV increases risk of having reactivation TB

    • Immunosuppression will give you atypical cxr findings

• Looking primarily for active tuberculosis 

Confirmatory testing:

• PPD: Sensitivity 60-100%

• QuantiFERON Gold: Sensitivity 81-96%

• Sputum Looking for AFB on smear (Ziehl-Neelson stain)

  • Variable Sensitivity: 20-60%

  • High specificity: 90-100%

• Culture

  • Slower results: 7days- 8 weeks

  • Gold standard: 99% sensitivity

• Rapid TB testing/ Cepheid Xpert MTB/RIF PCR assay

  • Respiratory for assistance in collection

  • 5 ml specimen

  • Rifampin resistance detection

  • Supposed to be a 2 hr turnaround

  • 2 negative sputum specimens at least 8 hrs apart: can remove from isolation

  • Sensitivity about 75-93%

*This is a sample rule out TB protocol that I adapted from Annals of Emergency Medicine October 2016 : http://www.annemergmed.com/article/S0196-0644(16)30920-9/fulltext

POTD: Tongue Blade Test in Minor Mandibular Blunt Trauma

Minor trauma with mild swelling and want to avoid imaging the patient?

Tongue blade test:

How is it done? Have the patient attempt to "clamp down on” a tongue blade between the teeth with enough force that the examiner is unable to pull it out from the teeth.

When the examiner twists the blade, a patient should be able to generate enough force to break or crack the blade.

A positive test: if the patient cannot clench the tongue blade between the teeth or if the examiner cannot break the blade while it is held in the patient’s bite. If the test is positive, imaging is indicated.  

A negative test: If the blade can be gripped by the patient and be broken by the examiner, fracture of the mandible is much less likely, and additional imaging is likely not needed. In a prospective series of 110 patients with suspected mandible fracture, the test was found to be approximately 96% sensitive and 65% specific.

Who is not likely to benefit from this test? Major trauma that would indicate further imaging, signs of mandibular fracture such as: intraoral bleeding, tooth malocclusion, trismus, ecchymosis, and intraoral swelling.

Sources: https://www.aliem.com/2010/07/trick-of-trade-tongue-blade-is-as/

^ Check out this awesome aliem post and especially for the video demonstration

Alonso L, Purcell T. Accuracy of the tongue blade test in patients with suspected mandibular fracture. J Emerg Med. 1995;13(3):297-304. [PubMed]

Peer IX