Dizziness and Vertigo

Introduction

Dizziness and vertigo are common complaints in Canadian primary care settings, accounting for approximately 3-5% of emergency department visits. As future Canadian physicians preparing for the MCCQE1, it's crucial to understand these symptoms in the context of our healthcare system and population demographics.

Pathophysiology

Understanding the underlying mechanisms of dizziness and vertigo is essential for MCCQE1 success. Let's break it down:

Differential Diagnosis

For MCCQE1 preparation, it's crucial to categorize causes of dizziness and vertigo:

Clinical Presentation and Assessment

When assessing patients with dizziness or vertigo, Canadian physicians should focus on:

1. Detailed history:

   • Onset and duration of symptoms
   • Aggravating or alleviating factors
   • Associated symptoms (e.g., hearing loss, tinnitus, neurological symptoms)

2. Physical examination:

   • Vital signs (including orthostatic measurements)
   • Neurological examination
   • Otoscopy
   • Special tests:
     • Dix-Hallpike maneuver for BPPV
     • Head impulse test for vestibular function
     • Romberg test for balance

3. Red flags (requiring urgent evaluation):

   • Sudden, severe vertigo with neurological deficits
   • New-onset headache
   • Neck pain or recent trauma

Diagnostic Approach

For MCCQE1 success, remember this diagnostic algorithm:

1. Determine if it's vertigo or non-vertigo dizziness
2. If vertigo, differentiate between peripheral and central causes
3. Consider systemic causes for non-vertigo dizziness

Management

Management strategies vary depending on the underlying cause:

1. BPPV:

   • Epley maneuver or other repositioning techniques
   • Patient education on home exercises

2. Vestibular neuritis:

   • Symptomatic relief (antiemetics, vestibular suppressants)
   • Vestibular rehabilitation

3. Meniere's disease:

   • Low-salt diet
   • Diuretics
   • Intratympanic steroid injections in severe cases

4. Central causes:

   • Treat underlying condition (e.g., stroke management, migraine prophylaxis)

5. Systemic causes:

   • Address underlying condition (e.g., medication adjustment, cardiac management)

Canadian Guidelines

The Canadian Society of Otolaryngology - Head & Neck Surgery provides guidelines for managing vestibular disorders:

1. Use of the Dix-Hallpike test as the gold standard for diagnosing BPPV
2. Recommendation of the Epley maneuver as first-line treatment for posterior canal BPPV
3. Emphasis on vestibular rehabilitation for chronic dizziness and balance disorders

Key Points to Remember for MCCQE1

• Differentiate between vertigo and other forms of dizziness
• Know the key features of common vestibular disorders (BPPV, vestibular neuritis, Meniere's disease)
• Understand the importance of the history and physical examination in diagnosis
• Be familiar with diagnostic tests and their interpretations
• Recognize red flags requiring urgent evaluation
• Understand the principles of vestibular rehabilitation
• Know when to refer to specialists in the Canadian healthcare context

Sample Question

# Sample Question

A 65-year-old woman presents to her family physician in Toronto with a 2-day history of severe vertigo, nausea, and vomiting. She reports that the room appears to be spinning around her, especially when she moves her head. She denies hearing loss, tinnitus, or neurological symptoms. On examination, her vital signs are stable, and neurological examination is normal except for nystagmus on lateral gaze. Which one of the following is the most appropriate next step in management?

- [ ] A. Immediate CT scan of the head
- [ ] B. Prescribe meclizine for symptomatic relief
- [ ] C. Perform the Dix-Hallpike maneuver
- [ ] D. Refer to an ENT specialist
- [ ] E. Start oral prednisone

Explanation

The correct answer is:

• C. Perform the Dix-Hallpike maneuver

This patient's presentation is highly suggestive of Benign Paroxysmal Positional Vertigo (BPPV), which is the most common cause of vertigo in older adults. The Dix-Hallpike maneuver is the gold standard diagnostic test for BPPV, as recommended by Canadian guidelines. It can both diagnose and potentially treat BPPV if followed by the appropriate repositioning maneuver.

A CT scan (option A) is not indicated as the first step, as there are no red flags suggesting a central cause. Meclizine (option B) may provide symptomatic relief but doesn't address the underlying cause and isn't the first step in management. Immediate referral to ENT (option D) is not necessary before attempting diagnosis and initial management in primary care. Oral prednisone (option E) is not a standard treatment for BPPV.

This question tests the candidate's ability to recognize the clinical presentation of BPPV and know the appropriate initial diagnostic approach, which aligns with Canadian guidelines and primary care practices.

References

1. Furman JM, Cass SP. Benign paroxysmal positional vertigo. N Engl J Med. 1999;341(21):1590-1596.

2. Bhattacharyya N, Gubbels SP, Schwartz SR, et al. Clinical Practice Guideline: Benign Paroxysmal Positional Vertigo (Update). Otolaryngol Head Neck Surg. 2017;156(3_suppl):S1-S47.

3. Canadian Society of Otolaryngology - Head & Neck Surgery. Position paper on the diagnosis and management of benign paroxysmal positional vertigo. J Otolaryngol Head Neck Surg. 2018;47(1):73.

4. Edlow JA, Gurley KL, Newman-Toker DE. A New Diagnostic Approach to the Adult Patient with Acute Dizziness. J Emerg Med. 2018;54(4):469-483.

5. Kerber KA, Baloh RW. The evaluation of a patient with dizziness. Neurol Clin Pract. 2011;1(1):24-33.