MIA 2012: Backes D, et al. Time-dependent test characteristics of head computed tomography in patients suspected of nontraumatic subarachnoid hemorrhage. Stroke. 2012 Aug;43(8):2115-9

ich_mca_berry_aneurysmBottom Line 1

  • 100% sensitive and specific if < 6 hours from headache onset
  •  90% sensitive if after 6 hours

A noncontrast head CT can effectively rule out atraumatic subarachnoid hemorrhage (aSAH) in patients who present with acute headache within six hours after ictus. Those who present outside this time window or present atypically for SAH (ie neck pain) require further workup, including a lumbar puncture.

2016-11-11T18:42:23-07:00

MIA 2012: IST-3 collaborative group et al. The benefits and harms of intravenous thrombolysis with recombinant tissue plasminogen activator within 6 h of acute ischaemic stroke (the third international stroke trial [IST-3]): a randomised controlled trial. Lancet. 2012 Jun 23;379(9834):2352-63.

Screen Shot 2013-06-01 at 7.22.47 AMBottom Line 1

Giving tPA to stroke patients within 6 hrs of symptom onset does not improve mortality or independence at 6 months.  However, patients might be a little “less disabled” while they are alive. Maybe.

(more…)

2016-11-11T18:42:29-07:00

Paucis Verbis: Acute vestibular syndrome and HINTS exam

Dizziness HINTS examWhat is your diagnostic approach to the acutely vertiginous patient?

The bottom-line question is: Is the cause peripheral or central in etiology?

In this great 2011 systematic review article in CMAJ on Acute Vestibular Syndrome (AVS), the authors review how (un)predictive elements of the history and physical exam are. By definition of AVS, symptoms must be continuous for at least 24 hours and have no focal neurologic deficits.

(more…)

2017-08-01T19:18:37-07:00

Trick of the Trade: Dix-Hallpike maneuver

Hallpike

The Dix-Hallpike maneuver is used to help diagnose benign paroxysmal positional vertigo (BPPV). 

  • Place the gurney’s head of the bed down flat. 
  • Reposition the patient so that s/he is sitting another 12 inches or so closer towards the head of the flat gurney. 
  • Rotate patient’s head 45 degrees.
  • Help the patient lie down backwards quickly.
  • The patient’s head should be hanging off of the gurney edge in about 20 degrees extension.
  • Observe for rotational nystagmus after a 5-10 second latency period, which confirms BPPV.

I find two things challenging in this maneuver. 

  • The patient often does not like to be moved AT ALL while feeling nauseously vertiginous. This even includes trying to reposition the seated patient closer to the head of the bed. This requires them to look behind them to see what where they are going, which sets off more vertigo.
  • In some of our ED rooms and hallways, the head of the gurney bed is often abutting a wall, a portable monitor, or some equipment. It takes a little fancy shuffling to make room for the Dix-Hallpike maneuver.

Trick of the Trade

Place blankets under the shoulders for the Dix-Hallpike maneuver
 
 

DixHallpikePillow

The key is to maintain about 20-30 degrees of neck extension to align the posterior semicircular canals with the direction of gravity. Placing several blankets under the patients’ shoulders can accomplish this same position without having to scoot the patient close to the gurney edge. I’m sure the patient would appreciate keeping their head movement to a minimum.

 
 
2016-11-11T18:52:14-07:00

Paucis Verbis: Spinal epidural abscess

afp20020401p1341-f2One of the most challenging diagnoses to make is that of a spinal epidural abscess (SEA), especially if you work in an Emergency Department which cares for many IV drug users and HIV patients. There’s never before been a published diagnostic guideline or algorithm which helps you with risk-stratification.

In the Journal of Neurosurgical Spine, a diagnostic guideline was prospectively evaluated on a small population (n=31) as compared to historical controls (n=55). They found that an ESR test had a sensitivity of 100% if a patient had at least 1 risk factor for SEA. A CRP test was much less helpful.
(more…)

2017-08-03T00:29:11-07:00