The Timing-and-Triggers Approach to the Patient With Acute Dizziness

Table of Contents

 

Although dizziness is common in the ED, there is incomplete understanding of the fundamentals of physical examination findings in dizzy patients. By using this new “timing-and-triggers” approach instead of the old “what do you mean, ‘dizzy?’” approach, you can more confidently make the correct diagnosis and ensure that patients with central causes of dizziness receive appropriate care quickly.

Define “vertigo,” “lightheadedness,” and “disequilibrium.” Why is the patient’s description of their symptom inherently unreliable?

How does the “timing-and-triggers” approach to dizziness more closely track with how other chief complaints are approached?

Neuritis versus stroke: how can you tell the difference?

When can a negative CT or MRI be false reassurance?

Why should you perform the “nystagmus” test portion of HINTS first?

What are the 5 questions you must answer “NO” to in order to rule out stroke?

When should you use the Epley maneuver? Semont? Lempert?

In a patient with triggered dizziness, what are the warning signs of a central cause?

1. Abstract
2. Case Presentations
3. Selected Abbreviations
4. Introduction
5. Critical Appraisal of the Literature
6. Etiology, Relevant Anatomy, Physiology, and Pathophysiology
7. Differential Diagnosis, Diagnostic Approach, and Misdiagnosis
   1. Symptom-Quality Approach
   2. Timing-and-Triggers Approach
   3. Misdiagnosis
8. Prehospital Care
9. Emergency Department Evaluation
   1. Acute Vestibular Syndrome
      1. Head Impulse–Nystagmus–Test of Skew (HINTS) Testing
         • Test 1: Nystagmus Testing
         • Test 2: Skew Deviation Testing
         • Test 3: Head Impulse Testing
         • Test 4: Targeted Examination
         • Test 5: Gait Testing
   2. Spontaneous Episodic Vestibular Syndrome
   3. Triggered Episodic Vestibular Syndrome
10. Diagnostic Studies
11. Treatment
12. Special Populations
13. Controversies and Cutting Edge
14. Disposition
15. Summary
16. Time- and Cost-Effective Strategies
17. Key Points
18. Risk Management Pitfalls for Dizziness in the Emergency Department
19. Case Conclusions
20. Clinical Pathways
    1. Clinical Pathway for the ATTEST Approach to Emergency Department Patients With Acute Dizziness
    2. Clinical Pathway for Diagnostic Evaluation of Patients With an Acute Vestibular Syndrome
21. Tables and Figures
    1. Table 1. Timing-and-Trigger-Based Vestibulara Syndromes in Acute Dizziness and Their Corresponding Differential Diagnosis
    2. Table 2. Summary of Useful Physical Examination Findings in Symptomatic Patients With the Acute Vestibular Syndrome
    3. Table 3. Diagnostic Criteria for Vestibular Migraine
    4. Table 4. Benign Paroxysmal Positional Vertigo Physical Examination, Type of Nystagmus, and Therapeutic Maneuvers
    5. Table 5. Characteristics of Patients With Triggered Episodic Vestibular Syndrome That Suggest a Central Mimic (CPPV) Rather Than Typical BPPV
    6. Figure 1. Inner Ear Anatomy
    7. Figure 2. Vestibular Anatomy and Physiology
    8. Figure 3. Mechanisms of Benign Paroxysmal Positional Vertigo
    9. Figure 4. Cerebrovascular Anatomy of the Labyrinth
    10. Figure 5. Head Impulse Test
22. Video Links
    1. Dix-Hallpike Maneuver
    2. Epley Maneuver
    3. Lempert (“barbecue”) maneuver
    4. Foster half-somersault maneuver for pc-BPPV
    5. Semont (liberatory) maneuver
    6. Gufoni maneuver
23. Reference

Abstract

Acute dizziness is a common presentation in the emergency department. Due to newer research, the diagnostic approach to dizziness has changed, now focusing on its timing and triggers of instead of the patient’s symptom quality (vertigo versus lightheadedness). Each timing-and-triggers category has its own differential diagnosis and diagnostic approach, which will aid emergency clinicians in distinguishing benign causes of dizziness from life-threatening causes. Brain imaging, even with magnetic resonance imaging, has important limitations in ruling out stroke presenting with dizziness. Benign paroxysmal positional vertigo can be treated with repositioning maneuvers at the bedside, offering cost-effective management options.

Case Presentations

The day shift signs out to you a 44-year-old previously healthy man. He is currently at CT. His dizziness started 6 hours previously and has been present ever since. He describes unsteadiness and “feeling like I am drunk,” and has vomited 3 times. He denies headache or neck pain, weakness, or numbness. His vital signs are normal. There is some left-beating horizontal nystagmus in primary gaze and in leftward gaze. The head impulse test is normal. The sign-out is that if his CT scan is normal, he can go home with meclizine and follow-up with his PCP in 2 days. That sounds reasonable, but you wonder if there is something else that needs to be considered...

The 70-year-old woman in room 3 complains of “lightheadedness” that has been going on for 5 days. It goes away at times, and gets worse when she gets out of bed. The dizziness has woken her from sleep several times. She has hypertension and high cholesterol. Her vital signs are normal. Sitting up in the stretcher, she is asymptomatic but feels apprehensive about moving her head. There is no nystagmus in primary gaze. You wonder if you should order a CT or if there is a better diagnostic test...

In room 7, there is a 58-year-old diabetic man whose triage chief complaint was syncope. On further questioning, he is reporting vertigo that is so severe it made him ease himself to the ground. There was no trauma, and it began abruptly 3 hours prior. Fingerstick glucose is 110 mg/dL. There is nystagmus on primary gaze that beats to the right, and when he looks to the right, the amplitude of the nystagmus increases. He is very nauseous and has vomited 3 times. A head impulse test is positive. Skew deviation is absent and he is mildly unsteady but can walk unassisted. You wonder if this could be stroke and whether the stroke team should be activated...

Selected Abbreviations

Introduction

It is unusual to work a shift in the emergency department (ED) without seeing at least 1 patient with the complaint of dizziness. The challenge with these patients is due, in part, to the fact that the traditional diagnostic paradigm, which was created nearly 50 years ago, is deeply flawed and leads to confusion. Newer studies strongly suggest that a different diagnostic paradigm based on “timing and triggers” of the dizziness rather than the traditional “symptom quality” (or the “What do you mean, ‘dizzy’?”) approach is a better approach.

Compounding this problem is the fact that many physicians—and even some general neurologists—have an incomplete understanding of the basic physical examination findings that are useful in evaluating the dizzy patient. Nystagmus, in particular, is poorly understood by many clinicians, and the head impulse test (HIT) has only recently been introduced to emergency medicine practice. The goal of this article is to bridge this knowledge gap and to review the tools and techniques that are available to assist clinical decision-making in the dizzy patient.

Based on the current literature and clinical experience, this issue of Emergency Medicine Practice presents a new, algorithmic approach to the diagnosis of acute dizziness. Although this approach to the dizzy patient takes a few extra minutes up-front, it will save time and expense later. More importantly, confidently making a correct diagnosis in a timely fashion may improve patient outcomes, such as reducing falls due to dizziness and improving long-term vestibular function.^1-3 In the case of transient ischemic attack (TIA), starting acute treatments reduces the outcome of stroke.^4,5

Critical Appraisal of the Literature

A literature search was performed in PubMed and the Cochrane Database of Systematic Reviews. PubMed was searched using the terms vertigo, dizziness, disequilibrium, OR lightheadedness (limited to title or abstract), limited to the English language, up to November 1, 2018. Relevant Cochrane reviews in the ear, nose, and throat (ENT) and neurology sections were searched. This yielded 22,697 titles (PubMed) and 6 Cochrane reviews. No emergency medicine guidelines exist; however, the American Academy of Neurology⁶ and the American Academy of Otolaryngology-Head and Neck Surgery⁷ published practice guidelines on benign paroxysmal positional vertigo (BPPV) that have some overlap with emergency medicine practice.

Importantly, one study analyzed the strength of the evidence base in the literature on dizziness and found it to be weak.⁸ Of the literature that does exist, most studies were done in settings or by subspecialists that render them not relevant to ED practice. Therefore, I have used judgment to identify the very small proportion of articles relevant to the management of the acutely dizzy patient by emergency clinicians. Additional references from these articles were identified.

An important first step in critically appraising the literature on dizziness is to analyze the landmark article by Drachman and Hart published in 1972 in the journal Neurology.⁹ This article influenced subsequent medical literature and practice over the ensuing decades, and it forms the foundation of the “symptom-quality” approach to dizziness that is taught across specialty lines. The authors (a neurologist and an ENT specialist) established a “dizziness clinic” to which patients were referred. The patients underwent 4 half-days of evaluation, including history and detailed physical examination. A diagnosis was assigned by the lead author. Methodologic limitations of this study included:

Small number of patients: Only 125 patients were enrolled over a 2-year period, of whom 21 were rejected for inadequate data and another 9 for lack of a diagnosis. Only 95 patients completed the study.

• Highly selected patient population: Recruited patients had to be fluent in English and available (and well enough) to return on 4 additional half-days for further testing in a clinic. These were not typical ED patients with dizziness, many of whom would have general medical conditions or be too sick (or die) to return for multiple repeat clinic visits.
• Lack of independent verification of the diagnosis: The lead author assigned a diagnosis without any external verification. To some extent, circular reasoning was applied, in that a peripheral vestibular disorder was typically assigned to patients with rotatory nystagmus.
• No long-term follow-up of patients: In addition to the lack of verification of the diagnosis, no follow-up was done, adding further ambiguity to the initial diagnostic accuracy.

Nonmethodologic limitations included:

• Lack of any brain imaging: Neither computed tomography (CT) nor magnetic resonance imaging (MRI) was available in 1970-1972.
• Some important diagnoses were not recognized at that time. Vestibular migraine was not an established diagnosis. Posterior circulation transient ischemic attack (TIA) presenting as isolated dizziness was not considered to occur.

The paradigm of “symptom quality” has never been prospectively validated, and the subjects of this study are not representative of ED patients with dizziness. Although the article was an important contribution in its time, it is fatally flawed. Newer evidence shows that its inherent logic is wrong.

Risk Management Pitfalls for Dizziness in the Emergency Department

1. “I thought that because the dizziness got worse with head movement, it had to be peripheral.”

This is a common misconception. Dizziness at rest in a patient with a cerebellar stroke or tumor often intensifies with head motion. It is crucial to distinguish dizziness that is triggered by movement (no dizziness at rest, but dizziness develops with movement) versus dizziness that is exacerbated by movement (dizziness is present at rest, but worsens with head movement).

3. “I ruled out a posterior circulation TIA because isolated dizziness is never due to ischemia; other brainstem findings will always be present.”

This is a misconception that stems from old expert opinion dating back to the mid-1970s. Newer studies make it clear that isolated dizziness is the most common transient symptom that precedes posterior circulation stroke and occurs in approximately 8% of these patients.

5. “The patient had a bad headache and said he had some transient double vision, but the Dix- Hallpike test was positive on both sides. I gave him meclizine for his BPPV.”

There are some symptoms that never occur with BPPV—including headache and double vision. One can never make a diagnosis of BPPV in a patient with severe headache or diplopia (even if transient). As well, the treatment for BPPV is a canalith repositioning maneuver such as the Epley maneuver, not meclizine.

Tables and Figures

Video Links

Dix-Hallpike Maneuver:

Epley Maneuver:

Lempert (“barbecue”) maneuver:

Foster half-somersault maneuver for pc-BPPV:

Semont (liberatory) maneuver:

Gufoni maneuver:

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study, such as the type of study and the number of patients in the study is included in bold type following the references, where available. In addition, the most informative references cited in this paper, as determined by the author, are highlighted.

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