Exam Accuracy for Vertigo – HINTS for New SAEM Guidelines

January 26, 2023

Written by Seth Walsh-Blackmore

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A general neurological exam has low sensitivity but high specificity for stroke in acute dizziness or vertigo. No modality is more sensitive than a HINTS exam by a trained provider.  

Why does this matter?
Dizziness and vertigo are among the most common chief complaints seen in the ED¹, often with high-resource, low-yield workups like CT imaging^2,3. This extensive review supports a bedside exam as the first-line modality to differentiate stroke from other etiologies.

Can I order this MRI with a HINTS exam? 
This was a systematic review and meta-analysis performed as part of an upcoming GRACE (aka SAEM guidelines) for acute dizziness/vertigo in the ED. Pooled sensitivity and specificity of various bedside exams to identify a stroke (ischemic or hemorrhagic) in patients with acute (less than two weeks), undifferentiated dizziness or vertigo was the primary outcome. Multiple specialties performed the exams. Presentations other than acute vestibular syndrome (AVS) were included.

The key results:

In studies evaluating exams by ED providers, the performance of the general neuro exam was similar to the pooled results. Most studies assessing the general exam had a high risk of bias and provided low-certainty evidence.

The HINTS/HINTS+ data are collected from studies with a low risk of bias and provide high-certainty evidence. The caveat is the examiners were trained neurologists or neurotologists in most cases. The limited data including EM examiners are poorly generalizable and highly variable.

In a neuroimaging review for this GRACE guideline, there is no modality with early sensitivity comparable to the HINTS exam performed by a trained neurologist. The application of HINTS by EM providers has pitfalls. However, there is evidence of high sensitivity by EM docs with 1-2 days of specialized training⁴. Given the potential benefits for patient safety and resource utilization, I anticipate the upcoming GRACE will recommend broader incorporation of HINTS into EM training. I would familiarize myself with HINTS and continue to perform a complete neuro exam, as always.

Source
Diagnostic accuracy of the physical exam in emergency department patients with acute vertigo or dizziness: Systematic review and meta-analysis for GRACE-3. Acad Emerg Med. 2022 Dec 1. doi: 10.1111/acem.14630. Online ahead of print.

Works Cited

1. Newman-Toker DE, Hsieh YH, Camargo CA, Pelletier AJ, Butchy GT, Edlow JA. Spectrum of dizziness visits to US emergency departments: cross-sectional analysis from a nationally representative sample. Mayo Clin Proc 2008;83(7):765–75.
2. Saber Tehrani AS, Coughlan D, Hsieh YH, et al. Rising annual costs of dizziness presentations to U.S.emergency departments. Acad Emerg Med 2013;20(7):689–96.
3. Shah VP, Oliveira J. e Silva L, Farah W, et al. Diagnostic accuracy of neuroimaging in emergency department patients with acute vertigo or dizziness: A systematic review and meta-analysis for the guidelines for reasonable and appropriate care in the emergency department. Acad Emerg Med 2022;
4. Gerlier C, Hoarau M, Fels A, et al. Differentiating central from peripheral causes of acute vertigo in an emergency setting with the HINTS, STANDING, and ABCD2 tests: A diagnostic cohort study. Acad Emerg Med 2021;28(12):1368–78