Acute Video-oculography for Vertigo in Emergency Rooms for Rapid Triage (AVERT)

Acute Video-oculography for Vertigo in Emergency Rooms for Rapid Triage (AVERT)

AVERT is a randomized controlled trial comparing video-oculography (VOG)-guided care to standard care to assess accuracy of diagnoses and initial management decisions for emergency department (ED) patients with a chief symptom of vertigo or dizziness suspected to be of vestibular cause. The trial will test the hypothesis that VOG-guided rapid triage (VRT) will accurately, safely, and efficiently differentiate peripheral from central vestibular disorders in ED patients presenting acute vertigo or dizziness, and that doing so has the potential to improve post-treatment clinical outcomes for these patients.

AVERT is a multicenter phase 2 clinical trial comparing a novel diagnostic strategy (VRT) to standard ED diagnostic care at three performance sites. The Specific Aims are to assess diagnostic accuracy, diagnostic workup costs, and estimate the short-term impact of correct diagnosis in anticipation of a larger, definitive phase 3 trial. Adult ED patients with a chief symptom of vertigo, dizziness, or unsteadiness, new or clearly worse in the previous 30 days, will undergo on-site vestibular function tests by trained research personnel using a portable, quantitative VOG recording device. Research personnel will also record a focused symptom history and bedside hearing tests. Eligible patients with at least one pathologic vestibular eye movement finding or pathologic ataxia will be randomized to VRT or standard ED care. Patients eligible for pre-randomization testing but excluded from randomization will be slated for the Observational Arm of the study and will undergo limited 1-month and 6-month phone follow-up. The VRT arm relies on an automated algorithm to interpret VOG results, thereby determining a patient-specific clinical care pathway. For safety, all VRT-arm study participants will undergo stroke protocol MRI before release. All randomized participants will undergo confirmatory testing at one week, including vestibular specialist exam and 1.5 or 3-Tesla research MRI combining stroke and internal auditory canal protocols. All randomized participants will also undergo 1-month and 6-month phone follow-up and medical record review to confirm diagnoses. Clinical findings, ED diagnoses, diagnostic resource utilization, treatments applied, and clinical events during follow-up will be recorded. A multidisciplinary, masked expert panel will adjudicate final diagnoses.

Inclusion criteria:

Adult (18 years and older) ED patients with all of the following (all determined pre-randomization):

• VESTIBULAR SYMPTOMS: presenting symptom of "vertigo" OR "dizziness" OR "unsteadiness" (as defined by consensus expert definitions in the International Classification of Vestibular Disorders).
• RELEVANT EXAM SIGNS*: pathologic nystagmus (spontaneous, gaze-evoked, or positional) by bedside VOG testing OR pathologic ataxia (gait, trunk, stance, limbs) by bedside ataxia examination.
• RECENT ONSET: symptoms AND signs* appear to be new or markedly worse in the past month. (*Exam signs are required for randomization, but not for the observational arm)

Exclusion Criteria

1. Excluded from Pre-Randomization Screening

   • Level 1 trauma or critical illness

   • Altered mental status (e.g., delirium, dementia) that would preclude active study participation (this includes patients with abnormal mental state due to alcohol intoxication or illicit substance, which are known, easily-recognized causes of dizziness or vertigo presentations to the ED)

   • Non-English speaking (enrollment of non-English speakers is not feasible given the logistics of identifying a translator and the need for rapid recruitment and randomization in the AVERT study; furthermore, the terms vertigo, dizziness, and unsteadiness may have different meanings in other languages)

   • Known pregnancy (all women of childbearing age who are enrolled will undergo a urine or serum beta human chorionic gonadotropin [hCG] pregnancy test prior to MRI to confirm no pregnancy, per local institutional guidelines)

   • Unable or unsafe to participate in screening, including VOG tests (as deemed by specific pre-enrollment risk assessment questions or ED provider and/or Study Coordinator judgment) including, but not limited to:

     • visual impairment sufficient to prevent visual fixation during the VOG testing
     • clinically-perceived risk to patient of participating in study (ED provider or staff concerns)
     • clinically-perceived risk to research staff (e.g., violence, blood/body fluid/respiratory precautions)
     • unstable cardiac status (given a single reported case of bradycardia with impulse testing)
     • acute cranio-cervical trauma or other condition (e.g., rheumatoid arthritis) that might lead to instability of the cervical spine that would be a contraindication to neck rotation during VOG testing

   • Obvious general medical cause (as judged by treating ED provider) including, but not limited to, acute myocardial infarction, pulmonary embolus, pneumonia, urinary tract infection, drug intoxication, etc.

2. Excluded from Randomization (Eligible for Observational Arm Follow-up)

   • Patient previously randomized in the AVERT Trial (previously screened but not randomized are eligible)

   • Unable to participate fully with study follow-up (particularly MRI) including, but not limited to:

     • unable to return for follow-up testing within 30 days
     • unable to undergo MRI because of contraindications (e.g., pacemaker, metallic foreign body, pregnancy) or other reasons (severe claustrophobia, too large or too heavy for MRI scanner)