Vertigo - HINTS plus testing
Indications
Vertigo (present for hours to days)
and
Nystagmus present (at time of assessment)
Contraindications (absolute in bold)
Acute trauma
Cervical spine disease
Vascular insufficiency (carotid or vertebrobasilar)
Limited neck mobility
Alternatives
Video-oculography as an inpatient (if available)
Informed consent
Verbal consent
Less complex non-emergency procedure with low risk of complications
Potential complications
Vertigo exacerbation
Vomiting
Procedural hygiene
Standard precautions
PPE: non-sterile gloves
Area
Any bed space
Staff
Procedural clinician
Equipment
None
Positioning
Patient sitting
Clinician sitting directly facing patient
Medication
Nil
Sequence (nystagmus testing)
Ask patient to look straight ahead (primary gaze)
Observe patient for nystagmus, noting the direction of the fast beat
Place piece of white paper lateral to patient and ask them to look to the side (20 degrees lateral gaze)
Do not ask the patient to fix vision on anything such as your finger (fixation will reduce nystagmus)
Observe patient for nystagmus, noting the direction of the fast beat
Sequence (vertical skew testing)
Ask patient to look straight ahead fixing their vision on your nose (primary gaze)
Cover one of the patient’s eyes with your hand (without touching the face)
Uncover the eye and cover the other eye
Observe each eye as it is uncovered for any vertical movement (they should remain motionless)
Sequence (head impulse testing)
Explain the test and ask the patient to relax their neck as much as possible
Ask patient to look straight ahead at your nose (primary gaze)
Hold onto the patient’s skull with both hands
Rotate patient’s head smoothly 20 degrees laterally in both directions (encouraging them to relax)
Briskly move the patient’s head from 20 degrees lateral back into the midline
Observe for a catch-up saccade (inability to maintain fixation with correction after movement ends)
Repeat this on both sides, randomly altering speed and direction to avoid patient anticipation
Sequence (finger rub hearing test)
Ask patient to look straight ahead at your nose
Rub your fingers together close to each ear
Ask the patient to tell you when you are rubbing your fingers
Note any new unilateral hearing deficit
Post-procedure care
Define testing as either:
A HINTS exam suggesting vestibular neuritis (all four signs present):
Unidirectional horizontal nystagmus, and
No vertical skew, and
Peripheral head impulse test (catch-up saccade indicating peripheral cause), and
No new hearing loss
Or
A HINTS exam suggesting stroke (any of these signs present):
Direction-changing or vertical nystagmus, or
Vertical skew, or
Central head impulse test (no catch-up saccade), or
New hearing loss
Tips
HINTS exam is worth doing well (it’s more sensitive than early MRI for detecting stroke in spontaneous vertigo)
Fixation block techniques (white paper above) are sometimes required to pick up spontaneous nystagmus
Describe the head impulse test results as peripheral or central (avoiding the confusion of positive and negative test results)
The Dix-Hallpike test is only performed on patients without spontaneous nystagmus
The Dix-Hallpike test and HINTS exam are never performed on the same patient
Discussion
There are two pathologies to consider in patients who present with nystagmus and vertigo lasting hours or days.
Vestibular neuronitis (peripheral nerve pathology)
Stroke (central pathology)
Most patients with vertigo lasting hours to days will have vestibular neuritis (peripheral nerve cause), but some of these patients have suffering a stroke (central cause). The HINTS (Head Impulse test, test of Nystagmus, Test of Skew) exam is used to reliably diagnose vestibular neuritis and so rule out stroke.
Nystagmus with an acute peripheral vestibular lesion is horizontal, present in primary position and beats in one direction regardless of eye positions. The slow phase is caused by the hypoactive affected ear, which moves gaze towards the lesion and away from fixation. The fast phase is the correction of gaze. By convention the direction of nystagmus is described as the direction of the fast beat. Peripheral nystagmus increases in gaze towards the direction of the fast phase and decreases in gaze towards the direction of the slow phase (Alexander’s law). A peripheral head impulse test (catch-up saccade) is seen when moving the head to midline from the affected side.
For example, the peripheral nerve lesion in right vestibular neuronitis will cause nystagmus always to the left (fast beat), which is exacerbated when looking left, and displays a catch-up saccade when moving the head from 20 degrees right into the midline. The test of skew will be normal.
The bedside hearing test was added to HINTS in 2013 as the HINTS plus exam. Hearing loss due to an anterior inferior cerebellar artery (AICA) stroke may rarely present with signs of a peripherally head impulse test with new hearing loss. There are only two reported instances of isolated AICA infarcts showing an abnormal head impulse test. Both these patients also had direction-changing horizontal nystagmus and positive skew and may have been picked up by a HINTS exam alone.
Peer review
This guideline has been reviewed and approved by the following:
Emergency Care Institute
Dr Peter Johns, Assistant Professor, Department of Emergency Medicine, University of Ottawa
Please direct feedback for this procedure to ACI-ECIs@health.nsw.gov.au.
References
Produced with and reviewed by Dr Peter Johns, Assistant Professor, Department of Emergency Medicine, University of Ottawa.
Roberts JR, Custalow CB, Thomsen TW. Roberts and Hedges’ clinical procedures in emergency medicine and acute care. 7th ed. Philadelphia, PA: Elsevier; 2019.
Dunn RJ, Borland M, O’Brien D (eds.). The emergency medicine manual. Online ed. Tennyson, SA: Venom Publishing; 2019.
Furman JM, Barton JJS. Evaluation of the patient with vertigo. In: UpToDate. Waltham (MA): UpToDate. 2020 Feb 11. Available from: https://www.uptodate.com/contents/evaluation-of-the-patient-with-vertigo
eTG complete. Melbourne: Therapeutic Guidelines; 2017 Nov. Stroke and vertigo. Available from: https://tgldcdp.tg.org.au/viewTopic?topicfile=stroke-and-vertigo
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Newman-Toker DE, Kerber KA, Hsieh YH, et al. HINTS outperforms ABCD2 to screen for stroke in acute continuous vertigo and dizziness. Acad Emerg Med. 2013;20(10):986-996. doi:10.1111/acem.12223
Edlow JA, Newman-Toker D. Using the physical examination to diagnose patients with acute dizziness and vertigo. J Emerg Med. 2016;50(4):617-628. doi:10.1016/j.jemermed.2015.10.040