Ménière Disease

1. THE 2-MINUTE PHYSIOLOGY (Rapid Pathophysiology)

• The Endolymphatic Insult: Ménière disease is a progressive peripheral vestibular disorder intrinsically linked to the accumulation of excess fluid within the endolymphatic space of the inner ear, a condition pathologically confirmed postmortem as endolymphatic hydrops.
• Mechanical Distortion and Autonomic Breakdown: The core mechanical breakdown is driven by fluid volume expansion that overstretches and distorts the delicate membranous labyrinth of the inner ear. This physical fluid-pressure barrier breach leads to compartmental shifts and physical distortion:
• Vestibular Apparatus Distortion: Mechanical pressure on the semicircular canals and otolith organs alters the baseline firing of vestibular hair cells, translating to episodic vertigo.
• Cochlear Pathophysiology: Hydropic expansion within the scala media compromises the basilar membrane, selectively dampening its mechanics to yield fluctuating low- to mid-frequency sensorineural hearing loss.
• Pressure-Shear Effects: High endolymphatic hydrostatic pressure stimulates localized acoustic pathway hypersensitivity, causing subjective tinnitus and a classic sensation of aural fullness in the affected ear.

2. THE BEDSIDE ACTION PLAN (Rapid ER Management)

• Immediate Resuscitation & Safety Assessment:
• Vertigo rarely compromises the airway directly, but severe, intractable vomiting can lead to dehydration and aspiration risk. Place the patient in a position of comfort (typically supine with eyes closed, avoiding head movement).
• Assess hemodynamic stability; if the patient is severely dehydrated from persistent vomiting, initiate intravenous fluid resuscitation with isotonic crystalloids.
• Acute Pharmacological Treatment:
• Antiemetic Therapy:
• Ondansetron: Administer 0.15 to 0.3 mg/kg IV push as a single dose (maximum single dose 8 mg) [Image 6]. Can repeat 4 to 8 mg IV every 8 to 12 hours as needed (do not routinely administer more than 16 mg in 24 hours) [Image 6]. For pediatric oral dosing, use weight brackets: 8–15 kg (2 mg PO), >15–30 kg (4 mg PO), >30 kg (4–8 mg PO) [Image 6].
• Metoclopramide: Administer 5 to 10 mg IV, IM, or PO. Pediatric Caution: Metoclopramide is not generally recommended in children due to extrapyramidal reactions and methemoglobinemia risk [Image 6].
• Vestibular Suppressants (Benzodiazepines & Antihistamines):
• Lorazepam: Highly effective as an alternative to antihistamines [Image 6]. Start with 0.5 to 1 mg IV, IM, or PO if the patient is unable to tolerate oral tablets. For patients \(\ge\)12 years, the maintenance dose is 0.25 to 2 mg PO every 8 to 12 hours as needed (maximum single dose 2 mg) [Image 6].
• Diazepam: Administer 1 mg IV, IM, or PO.
• Diphenhydramine: Administer 1 mg/kg PO every 6 hours as needed (maximum single dose 50 mg). Clinical warning: Chronic use of antihistamines may impede central vestibular recovery; limit use to the acute phase.
• Second-Line and Specialized ED Treatments:
• Prednisone: Consider 1 mg/kg PO daily for 7 to 14 days only in severe, refractory, disabling cases that have failed standard outpatient diuretic (e.g., hydrochlorothiazide) or betahistine therapy.
• Betahistine: If initiating outside the U.S., dose at 8 to 16 mg PO daily for 2 weeks (can increase to every 8 hours based on tolerance); note that Betahistine is not available in the U.S. [Image 5].
• Acetazolamide & Diuretics: Do not routinely use or prescribe diuretics or acetazolamide from the ED; consult ENT if considering [Image 5, Image 6].
• Trigger Avoidance Counseling: Direct the patient to strictly eliminate common dietary and lifestyle triggers: high salt intake, caffeine, ethanol (alcohol), nicotine, stress, MSG (monosodium glutamate), and food/environmental allergens.

3. THE DIAGNOSTIC GRID (Differential Diagnosis & Workup)

Top "Can't-Miss" Differential Diagnoses (Ménière Mimics)

1. Posterior Circulation Stroke (PICA/AICA territories): Can present with sudden-onset vertigo and nystagmus. Sparing of the cranial nerves and preserved ambulation point away from stroke, but any new focal neurological deficit or central nystagmus pattern mandates stroke activation.
2. Vestibular Migraine: The most common alternate diagnosis, occurring 8 to 10 times more frequently than Ménière disease. It is almost impossible to distinguish from Ménière in the ED setting. It classically presents with episodic vertigo in a patient with a personal history of migraines.
3. Vertebral Artery Dissection: Presents with severe unilateral neck or posterior occipital headache with rapidly progressive cerebellar/brainstem signs (vertigo, vomiting, ataxia). Often triggered by minor cervical trauma.
4. Vestibular Schwannoma (Acoustic Neuroma): A slow-growing tumor of the vestibular nerve. Presents with asymmetric, progressive sensorineural hearing loss, tinnitus, and gradual disequilibrium rather than hyperacute spontaneous attacks.
5. Benign Paroxysmal Positional Vertigo (BPPV): Differentiated by brief vertigo episodes (lasting <2 minutes) that are strictly triggered/provoked by head position changes rather than spontaneous attacks.

Prioritized Diagnostic Workup Strategy

• Bedside Glucose Screen: Checked immediately on arrival to rule out hypoglycemia as a stroke/dizziness mimic.
• Focused Otoneurological Exam: Assess nystagmus (unidirectional peripheral vs. multidirectional central), test cranial nerves, evaluate the cerebellum (dysmetria, Romberg), and perform a detailed gait assessment.
• Bedside Hearing Evaluation: Perform finger rub and Rinne/Weber testing to document subjective hearing deficits.
• Screen for Ototoxic Exposures: Formally review the patient's medication list for exposures to aminoglycosides, loop diuretics, antimalarials, chemotherapeutic agents, or high-dose NSAIDs.
• 12-Lead ECG: Routinely perform an ECG to screen for cardiac dysrhythmias (e.g., atrial fibrillation, bradycardia) which can cause transient cerebral hypoperfusion mimicking episodic dizziness.
• CT / MRI Head and Neck: Obtain a non-contrast head CT only if a cerebellar bleed or stroke is suspected. If a stroke or dissection is highly suspected, prioritize brain MRI (DWI sequences) and CTA/MRA of the head and neck.

4. THE VISUAL BOARD (ECG / POCUS / Imaging)

Electrocardiography (ECG) Checklist

• Check the 12-lead ECG for conduction delays, prolonged QT intervals, or tachy/bradyarrhythmias (such as atrial fibrillation or sinus node disease). Systemic perfusion failure must be ruled out before attributing symptoms to a primary inner ear pathology.

Neuroimaging Checklist

• Emergent Non-contrast Head CT: Recognize that head CT has extremely poor sensitivity for posterior circulation strokes. A normal CT must never be used to "rule out" central pathology in a patient with a concerning neurological exam or persistent central symptoms.
• Magnetic Resonance Imaging (MRI): Symmetrical or asymmetrical T2/FLAIR hyperintensities can point to central mimics like MS. MRI is the gold standard to rule out a posterior fossa mass, such as a vestibular schwannoma, in patients presenting with asymmetric sensorineural hearing loss.

Bedside Physical Exam Checklist

• **Nystagmus Evaluation:**Peripheral nystagmus in vestibular neuritis/labyrinthitis is classically horizontal and unidirectional (beats away from the diseased side, worsens when looking in the direction of the fast phase). Vertical, rotatory, or bidirectional nystagmus signifies a central process.
• Gait and Cerebellar Testing: Carefully document the patient's gait. Patients with peripheral vestibular disorders like Ménière prefer to remain still but can usually ambulate with assistance; an inability to sit or stand independently is a central red flag.

5. THE SCORING MATRIX (Risk Stratification & Guidelines)

Definite Ménière Disease Diagnostic Criteria

To meet the consensus guidelines for definite Ménière disease, the patient must fulfill the following:

1. Vertigo Attacks: Two or more spontaneous attacks of vertigo, each lasting 20 minutes to 12 hours.
2. Documented Hearing Loss: Audiometrically documented fluctuating low- to mid-frequency sensorineural hearing loss in the affected ear on at least one occasion before, during, or after one of the vertigo episodes. (Note: formal audiometry is not conducted in the ED but requires outpatient referral.)
3. Aural Symptoms: Fluctuating aural symptoms (hearing loss, tinnitus, or fullness) in the affected ear.
4. Exclusion of Mimics: Other vestibular diagnoses have been excluded by appropriate investigations.

Probable Ménière Disease Diagnostic Criteria

To meet the consensus guidelines for probable Ménière disease, the patient must fulfill:

1. Vertigo/Dizziness Episodes: At least two episodes of vertigo or dizziness lasting 20 minutes to 24 hours.
2. Aural Symptoms: Fluctuating aural symptoms (hearing loss, tinnitus, or fullness) in the affected ear.
3. Exclusion of Mimics: Alternate causes excluded by other diagnostic tests.

The ATTEST Mnemonic for Undifferentiated Dizziness

The clinician should apply the ATTEST framework to categorize the dizzy patient rather than relying on inconsistent descriptions of "lightheadedness" vs. "spinning":

• A: Associated symptoms (hearing loss, tinnitus, headache, focal deficits).
• T: Timing (onset, duration of individual episodes).
• T: Triggers (spontaneous vs. positional head movements vs. orthostatic changes).
• ES: Examination signs (nystagmus pattern, gait, cerebellar testing).
• T: Testing (ECG, bedside glucose, selective neuroimaging).

6. THE DANGER ZONE (Pitfalls & Critical Actions)

Deadly Cognitive Traps & Trainee Pitfalls

• The "Type of Dizziness" Anchoring Bias: Forcing the patient to distinguish whether their dizziness is "spinning vertigo," "presyncope," or "disequilibrium." This is highly inconsistent, clinically unreliable, and a major driver of diagnostic error. Trainees must focus strictly on timing, duration, and triggers.
• Chronic Antihistamine Prescription: Writing a long-term prescription for meclizine or diphenhydramine on discharge [17, Image 6]. Antihistamines suppress the vestibular system and directly impede central compensation/recovery. Limit these agents strictly to short-term, acute symptom control.
• The Falsely Reassuring CT / Early MRI: Discharging a patient with persistent, severe vertiginous symptoms because their head CT was normal. Head CT misses the vast majority of cerebellar strokes. Furthermore, early MRI can be falsely negative in up to 15% to 20% of posterior circulation strokes within the first 48 hours of symptom onset.
• Failing to Walk the Patient: Discharging a dizzy patient without formally observing them walk. Any patient who cannot ambulate independently or safely must not be discharged from the ED, as an abnormal gait is often the sole indicator of a dangerous central process [75, e1].

Mandated Board-Exam Critical Actions

• Document a complete cranial nerve and cerebellar exam (specifically Romberg, dysmetria, rapid alternating movements, and visual fields) to rule out a central posterior fossa mimic.
• Observe and explicitly document the patient's gait prior to discharge.
• Check and document a point-of-care capillary glucose immediately upon arrival for any dizzy or altered patient.
• Obtain a 12-lead ECG to evaluate for a cardioembolic or dysrhythmic source of transient dizziness.
• Arrange rapid, dual outpatient follow-up with both Otolaryngology (ENT) and Audiology for definitive diagnostic confirmation.

7. MCQ MASTERCLASS (Written Exam Tips)

• High-Yield "Buzzwords" and Key Associations:
• "Endolymphatic hydrops" is the classic histopathological finding associated with Ménière disease.
• "Spontaneous vertigo lasting 20 minutes to 12 hours" is the diagnostic timing window for definite Ménière.
• "Asymmetric low- to mid-frequency sensorineural hearing loss" is the pathognomonic audiometric description.
• "Aural fullness and low-pitched tinnitus" point directly to pressure effects within the scala media.
• Differentiating Distractors:
• The "Betahistine in the U.S." Trick: Written questions may ask for the best outpatient maintenance medication. Be careful—Betahistine is not approved or available in the United States, though it is widely used internationally [Image 5]. For U.S. board exams, the correct answer for maintenance will typically be a low-sodium diet and a thiazide diuretic.
• The "Dix-Hallpike" Trap: Questions will describe a patient with severe vertigo and ask for the next diagnostic maneuver. If the vertigo is spontaneous and lasts hours (Ménière), Dix-Hallpike is a distractor; it is only indicated for triggered, positional vertigo lasting seconds (BPPV).
• The "Emergency CT scan" Distractor: Recommending an emergent head CT to evaluate uncomplicated, typical episodic Ménière symptoms. This is an incorrect, low-value resource utilization; neuroimaging is only indicated if central red flags are present.

8. THE BOARDROOM SCRIPT (OSCE & Oral Board Tips)

• Triage and Stabilization Script:
• "This patient presents with acute, severe, spontaneous vertigo accompanied by unrelenting nausea and vomiting. Because sudden, severe neurological symptoms can represent life-threatening emergencies, I will place the patient in a monitored resuscitation bay, establish intravenous access, and immediately check a point-of-care capillary glucose to rule out hypoglycemia. I will assess their hemodynamic stability, as severe vomiting can lead to dehydration, and administer an initial crystalloid fluid bolus if indicated.".
• Mandatory Physical Exam Phrasing:
• "I will perform a meticulous, focused otoneurological and cerebellar examination. I will explicitly test all cranial nerves, assess for central versus peripheral nystagmus, and test cerebellar function using Romberg, rapid alternating movements, and finger-to-nose testing to look for dysmetria. I will assess their hearing at the bedside using a finger-rub test and Rinne/Weber. Most importantly, I will perform a formal gait assessment and document whether the patient can safely and independently ambulate before considering discharge.".
• Diagnostics and Management Phrasing:
• "Ménière disease is a clinical diagnosis. Because this patient has spontaneous, episodic vertigo lasting hours, accompanied by fluctuating low-frequency hearing loss, tinnitus, and aural fullness, I have a high index of suspicion. I will obtain a routine 12-lead ECG to rule out a dysrhythmic mimic. I will withhold emergent head CT or MRI, recognizing that CT has poor posterior fossa sensitivity, unless the neurological exam reveals central red flags.".
• "To manage their acute symptoms, I will administer Ondansetron 0.15 mg/kg IV (up to 8 mg) for antiemetic control and Lorazepam 0.5 to 1 mg IV for vestibular suppression. I will strictly avoid initiating long-term antihistamine therapy as this delays central compensation. I will counsel the patient to avoid key triggers, specifically high salt intake, caffeine, nicotine, alcohol, stress, and MSG.".
• Disposition Phrasing:
• "If the patient's vertigo is controlled, they can ambulate safely without assistance, and they are tolerating oral fluids, they can be safely discharged home. I will provide strict return precautions to seek immediate care for any focal weakness, numbness, or worsening headache. I will arrange secure, close outpatient referrals to both Otolaryngology and Audiology for formal audiometry, vestibular testing, and electrocochleography to establish a definitive diagnosis."