The HINTS exam is a group of three bedside tests used to assess people experiencing acute dizziness, vertigo, nystagmus, head motion intolerance, and nausea/vomiting, also known as acute vestibular syndrome (AVS).
Understanding the HINTS Exam
The HINTS exam is a crucial tool in differentiating between central and peripheral causes of vertigo. This is essential because central causes, like strokes, can be life-threatening and require immediate intervention. The exam consists of three key components:
- Head Impulse Test: Evaluates the vestibulo-ocular reflex (VOR). A normal VOR is when the eyes remain fixated on a target during rapid head turns, but an abnormal result would be an indication that there is a peripheral vestibular issue, like labyrinthitis.
- Nystagmus: Observes the direction and characteristics of involuntary eye movements. Certain patterns, like unidirectional nystagmus that changes direction with gaze are concerning for a central cause, whereas, nystagmus that beats in the same direction is more of a peripheral cause.
- Test of Skew: Assesses vertical misalignment of the eyes, which is often indicative of a central issue.
Why is the HINTS Exam Important?
The HINTS exam provides a rapid, non-invasive method for assessing individuals presenting with acute vertigo. It is particularly valuable because it can help clinicians quickly identify patients who require immediate neuroimaging and neurological consultation. The main goal is to differentiate between benign peripheral vestibular disorders and potentially life-threatening central causes, such as posterior circulation strokes.
How is the HINTS Exam Performed?
The HINTS exam is done at the bedside and does not require specialized equipment. Clinicians use their clinical skills to observe and interpret the patient’s responses during the three tests.
Summary of the HINTS Exam:
| Test | Description | Significance |
|---|---|---|
| Head Impulse | Rapidly turn the patient's head while the patient fixates on a target. | Abnormal results often indicate peripheral vestibular pathology. |
| Nystagmus | Observe and assess the characteristics of any involuntary eye movements. | Direction-changing nystagmus with change in gaze often suggests a central cause. |
| Test of Skew | Cover and uncover each eye observing for vertical misalignment. | Vertical misalignment is suggestive of a central pathology. |
By utilizing these bedside tests, the HINTS exam offers a simple and effective method for identifying serious causes of acute vertigo.
