Vertigo

Well, I was publicly called out this week to do a post, so I better deliver. Thanks much for the suggestion,  my goal is always to provide interesting, relevent content that helps you out in clinic.  Remember that you can search the whole blog with the search box, tags, or use the big categories at the top of the page. Archives are there to help you!

Anyway… on to vertigo!

Vertigo is a sensation of movement without moving.  If you’ve done this…

or this…or this…

then you know vertigo.

A big branch point in the differential diagnosis is Central vs Peripheral causes. Central causes are the “scarier” ones: brainstem or cerebellar stroke/TIA or MS. Peripheral causes are the ones we are more comfortable diagnosing and treating: BPPV, Meniere’s diease, vestibular neuritis, acoustic neuroma. Migrainous vertigo can walk the line between central and peripheral, and have features of both.

Most vertigo has some postural instability associated, and it often feels worse to move the head in the midst of an attack. Specific, predictable maneuvers (like rolling over in bed) that precipitate vertigo should make you think of BPPV. Most patients with peripheral causes of vertigo should be able to walk. When the postural instability is so severe that they can’t walk, that points toward a central cause.

Vertigo doesn’t last forever. Even with permanent damage to the vestibular system, the body compensates and the vertigo subsides. However, the time course can help you with the diagnosis: BPPV usually is short-lived– a minute or less, while migrainous vertigo can last minutes to hours.  Vestibular neuritis, brainstem infarction and MS can produce vertigo that is severe and lasts for days.

Nystagmus is often found with vertigo. Central causes can have nystagmus in any direction, while peripheral causes will only have horizontal nystagmus. Nystagmus that reverse direction when the patient looks from right to left suggests a central cause.

Apart from the Romberg and nystagmus, an otherwise normal neurologic exam suggests a peripheral cause.  If your patient has weakness, cerebellar signs, or abnormal reflexes, be worried about those central causes.  Interestingly, hearing loss or tinnitus does suggest a peripheral cause, most commonly Meniere’s disease or acoustic neuroma.

Of course, there are some specific maneuvers that can help you out. The Dix Hallpike maneuver is most helpful if your patient is not symptomatic when you examine them. If you can elicit the vertigo and/or nystagmus with the maneuver, it is suggestive of BPPV.  My favorite video demonstration of Dix-Hallpike is here.

There is also the Head Thrust Maneuver. This is useful for diagnosing vestibular neuritis as compared to a central vertigo. The concept is that the patient focuses on a distant object, and tries to maintain focus while the examiner abruptly turns the patient’s head about 15 degrees. A normal response is to keep the eyes fixed on the object.  Patients with cerebellar lesions have a normal response. The abnormal response is for the eyes to deviate, toward the lesion, and then slowly return to the object. Peripheral causes of vertigo, like vestibular neuritis, tend to result in an abnormal head thrust response.

Up To Date has a great table to help differentiate the common and concerning causes of vertigo. It is so good, I’ve just reproduced it here for you.  Another great resource for dizziness in general is this AAFP article (if you don’t have institutional access, Am Fam Physician. 2010 Aug 15;82(4):361-368).
Time course Suggestive clinical setting Characteristics of nystagmus• Associated neurologic symptoms Auditory symptoms Other diagnostic features
Benign paroxysmal positional vertigo Recurrent, brief (seconds) Predictable head movements or positions precipitate symptoms Peripheral characteristics None None Dix-Hallpike maneuver shows characteristic findings
Vestibular neuritis Single episode, acute onset, lasts days Viral syndrome may accompany or precede vertigo Peripheral characteristics Falls toward side of lesion, no brainstem symptoms Usually none Head thrust test usually abnormal
Meniere disease Recurrent episodes, last minutes to several hours Spontaneous onset Peripheral characteristics None Episodes may be preceded by ear fullness/pain, accompanied by vertigo, unilateral hearing loss, tinnitus Audiometry shows unilateral low frequency sensorineural hearing loss
Migrainous vertigo Recurrent episodes, last several minutes to hours History of migraine Central or peripheral characteristics may be present Migraine headache and/or other migrainous symptoms accompanying or following vertigo Usually none Between episodes, tests are usually normal
Vertebrobasilar TIA Single or recurrent episodes lasting several minutes to hours Older patient, vascular risk factors, and or cervical trauma Central characteristics Usually other brainstem symptoms Usually none MRI w/DWI may demonstrate vascular lesion
Brainstem infarction Sudden onset, persistent symptoms over days to weeks As above Central characteristics Usually other brainstem symptoms, especially lateral medullary signs Usually none; an exception is anterior inferior cerebellar artery syndrome MRI will demonstrate lesion
Cerebellar infarction or hemorrhage Sudden onset, persistent symptoms over days to weeks Older patient, vascular risk factors, especially hypertension Central characteristics Gait impairment is prominent. Headache, limb dysmetria, dysphagia may occur. None Urgent MRI, CT will demonstrate lesion
* Other diagnoses described in text “Pathophysiology and differential diagnosis of vertigo”.
• Peripheral characteristics of nystagmus: horizontal or horizontal-torsional; suppresses with visual fixation, does not change direction with gaze. Central characteristics of nystagmus: may be horizontal, torsional, or vertical, does not suppress with visual fixation, may change direction with gaze.
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Night shift at the Sawmill

Here’s one of those things that I should have learned about in medical school, but really didn’t.  If my patient’s snoring isn’t caused by sleep apnea, then I’m tapped out as to what to do about it.  But Twitter and AMR inspired me to do a little research this week.

Some snoring is nearly universal, and up to 45% of us are habitual snorers.  So be careful before you criticize your spouse or parent too much, next time you have a cold, or get pregnant, or gain that extra 5 pounds, your criticism may come back to you.  Funny how that works.

The overall cause of snoring is increased upper airway resistance, and the reason for that can be pretty broad. Certainly OSA can also be a cause of the snoring, but may also be a result. The more resistance there is, the more likely that arousals and apnea are also present.  Nasal congestion, tonsillar hypertrophy, obesity, and craniofacial abnormalities like acromegaly can all increase resistance by just having less room for air to move through.  Sort of like a stenotic valve causes a murmur.

So why care?  Certainly we all know the health risks of untreated sleep apnea, that I won’t cover here, but what if there isn’t apnea?  There have been some mixed results, but there are few observational studies that link snoring (without apnea) to hypertension and atherosclerosis.  But in reality, it is often the bed partner who urges the patient to get some help.  Marital harmony and relieving embarrassment are real issues for patients and probably the place where treatment can have the most benefit.

Treatment for snoring can take a variety of approaches.  Weight loss alone can go a long way. A very small observational study showed statistically significant decreases in snoring with as little as 3kg of weight loss, and near absence of snoring in patients who lost 8kg.  Other lifestyle changes that are always good: quit smoking and drinking.  Snorers are more likely to use both substances.

Changing sleep position may work.  Many snorers sleep on their backs, which causes open mouths, and smaller airways.  About ½ of patients can be trained to sleep on their sides instead.  The entrepreneurs of the world have come up with a ton of products, but a simple home remedy is to attach a tennis ball to the back of a T-shirt.  You can pin a sock to the shirt, and then put the ball inside, or you can duct tape the ball on the back of the shirt.

Increasing nasal patency may do the trick.  During a cold, nasal decongestants can be helpful (although only for 3 days or you risk rhinitis medicamentosa). Nasal steroid may help some, and are worth a trial.  Some nasal dilators have been proven effective, particularly the external ones like Breathe Right strips. 

Finally, mechanical appliances (mouth guards, chin straps) or surgery may be the answer for some, if the above approaches don’t help.

A good bit of this information came from a great patient education website that I found. It is a great place to direct patients to find out info about all sorts of things that really don’t need a “medicine” to fix.  Sleep, diet, stress relief, even a variety of psychiatric topics such as ADD, bipolar disorder, and PTSD.

Green

You  might have noticed a layer of green over all of Birmingham.  We’ve had a few days of warm weather, and that was enough to get everything blooming.  I have had more  than a few patients tell me that their allergies are worse in Bham than anywhere else.  You can thank the bowl that we sit in (also known as Jones Valley-a little Bham trivia bonus) for that bit of loveliness.
A common question is how to tell between allergic rhinitis and upper respiratory infections.  Both are really common at urgent care visits this time of year, and sometimes its useful to get an accurate diagnosis.

Allergic Rhinitis
Upper Respiratory Infection
Symptoms
Sneezing, rhinorrhea, nasal congestion and itching
Eye symptoms
No fever
Sore throat , nasal obstruction, rhinorrhea, sneezing
Fever, myalgias (particularly with influenza)
Progression
Everything at once, during the right time of year
Perennial allergies can go on year round (indoor allergens)
Usually sore throat first, then nasal sx, then cough
Exam
Pale, bluish mucosa (mouth and nose)
Red, swollen nasal mucosa and pharyngeal erythema
Differential diagnosis
URI
Vasomotor rhinitis
Rhinitis medicamentosa
Pertussis: prolonged severe coughing >2 weeks, not much other sx.
Influenza: high fever, myalgias
Associated Sx/ Prognosis
20-40% with asthma
Eventual acute sinusitis
Acute sinusitis: facial pain, purulent mucus

Rhinitis treatment is often similar to URI treatment, but there is some more data that treatments are beneficial with allergic rhinitis. Mainstay is nasal steroids and antihistamine.   Dr. Huddle would recommend chlorpheneramine (a first generation “sedating” antihistamine) over the second generation antihistamines. However, this is quite sedating, and may have more anticholinergic side effects. Be careful with your elderly patients, and particularly those prone to urinary retention.  Also consider decongestants- pseudoephedrine works better and is worth standing in line at the pharmacy window. 

Evidence based URI treatment is really non-existent. Nasal steroids and antihistamines are probably  less helpful.  Nasal ipatropium or nasal cromolyn may be useful, but are pricey.  I tend to tell people to get one of the myriad combo cold/sinus medicines in the drug store- they want a decongestant, something for aches/fever, and a cough suppressant or expectorant. Again, waiting in line for pseudoephedrine is worth it, particularly if they have a lot of sinus symptoms.

Here’s a link to the Annals of Internal Medicine In the Clinic article on allergic rhinitis
http://annals.org/article.aspx?articleid=734087