Tutorial #32 - Acute Headache Flashcards
List the clinical features of a headache that are associated with serious pathologies.
- History: x10
- Physical exam: x6
History: x10
- Rapid and severe at onset
- No similar headaches in the past
- Concomitant infection
- Altered mental status or seizure
- Association with exertion (exercise, sexual intercourse)
- Age >50
- Immunosuppression: HIV, chronic glucocorticoid use
- Visual disturbances
- Pregnancy or post part
- Medications, illicit drugs (anticoagulants, sympathomimetic agents)
Physical exam: x6
- Abnormal vitals
- Neurologic abnormalities
- Decreased LOC
- Meningismus
- Toxic appearance
- Papilledema or other ophthalmologic findings
What are the three general categories of dangerous causes of headache that are screened for?
- Infection
- Vascular and bleeding catastrophes
- Intracranial masses
A patient presents to the ER with what they describe as the worst headache of their life that had an onset of only a few minutes. Since this headache started, they are now experiencing severe neck pain, and some nausea and vomiting. What is the most likely diagnosis?
- Subarachnoid hemorrhage
A non-contrast CT scan of the head is nearly 100% sensitive if done under X hours.
What is X?
6 hours
What are the expect lab findings for CSF in a patient with bacterial meningitis?
Elevated WBC > 500/uL
Decreased Glucose < 2.2 mmol/L
Don’t worry about memorized specific numbers
What are SIX indications for a CT prior to an LP?
- Altered mentation
- Focal neurologic signs
- Papilledema
- Seizure within the previous week
- Impaired cellular immunity
- Trauma
What are the red flags for a secondary headache?
- Thunderclap onset
- Fever and meningismus
- Papilloedema
- Unexplained focal neurologic signs
- Unusual headache attack precipitants
- Headache onset after age 50
A 43 year old female patient presents to the clinic with a recurrent headaches that only occur at home in her basement in the winter. The same thing is happening to her girlfriend when she visits.
What test should be ordered to rule in/out your diagnosis, and what are you looking for?
Arterial blood gas (ABG) -> carboxyhemoglobin
What are effective rule-out tests for subarachnoid hemorrhage?
- Absence of RBC or xanthochromia on LP
- Negative CT within 6 hours
What is Evidence Based Medicine?
The intersection between:
* Clinical judgement
* Relevent scientific evidence
* Patients’ preferences and values
What is the Choosing Wisely statement regarding migraine-type headaches?
Don’t order neuroimaging or sinus imaging in patients who have a normal clinical examination, who meet diagnostic criteria for migraine, and have no “red flags” for a secondary headache disorder.
Red flags for a secondary headache include:
- thunderclap onset
- fever and meningismus
- papilloedema
- unexplained focal neurological signs
- unusual headache attack precipitants
- headache onset after age 50
What are 3 harms/pitfalls related to diagnostic testing?
- Patient harms including physical harm, psychological harm, adverse reaction to testing (like allergic reaction)
- Cost/system resources wasted
- Limited utility in situations where a test is unlikely to change outcome
List potential complications of lumbar puncture (x8)
- Post-LP headache (10-30%)
- Back pain (25%)
- Minor neurologic symptoms such as radicular pain or numbness (15%)
- Bleeding (2% - usually related to anticoagulation or bleeding disorder)
- Paralysis (1.5% - all related to bleeding and anticoagulation)
- Infection (<1%)
- Cerebral herniation (rare –an issue when there is high ICP)
- Late onset of epidermoid tumors of the thecal sac (rare)
What does shared decision making mean?
SDM means sharing an understanding of the various options and incorporating patient preference, particularly when multiple reasonable options exist.
What number is a “good” or “strong” positive likelihood ratio that results in large change to post-test probability?
+LR of 10 = large increase
What number is a “good” or “strong” negative likelihood ratio that results in large change to post-test probability?
-LR of 0.1 = large decrease
What number is a “moderate” positive likelihood ratio that results in moderate/medium change to post-test probability?
+LR of 5 = moderate increase
What number is a “moderate” negative likelihood ratio that results in moderate/medium change to post-test probability?
-LR of 0.2 = moderate decrease
What are positive predictors for migraine headache?
Without Aura: Unilateral, pulsating quality, moderate to severe intensity, aggravation by physical activity, nausea and/or photophobia and phonophobia.
With Aura: Recurrent attacks, lasting minutes to an hour, unilateral fully reversible visual, sensory or other central nervous system Positive Jacksonian symptoms that usually develop gradually and are usually followed by headache and associated migraine symptoms.
What number of a likelihood ratio means “no effect” or “no change” to post-test probability?
+LR or -LR of 1 = no effect
What are positive/negative predictors for giant cell arteritis?
Positive predictors:jaw claudication (+LR 18, -LR 0.5), erythematous/nodular/tender temporal artery, transient or ongoing monocular visual loss, symptoms of PMR (aching and morning stiffness in pelvic girdle, shoulder girdle and torso).
Negative predictors: Normal ESR (but many cases come with only slight elevation in ESR), age < 50 years.
ESR and CRP are usually elevated (positive LR 41, negative LR 0.12)
What are positive/negative predictors for brain tumor?
Positive Predictors Strong: Seizures, focal neurological findings (including papilledema)
Weak: nausea/vomiting, headache described as “dull and constant,” gradually worsening headache over months, worse with cough/bending forward/Valsalva/exertion, headache awakens patient at night, severe morning headache
Negative Predictors None really, beyond absence of the red flag positive predictors
What are positive predictors for subarachnoid hemorrhage?
Most patients are ambulatory and describe a sudden severe “thunderclap” headache (sensitivity 97%). Half of cases occur without strenuous activity. Nausea/vomiting occur in 77% of patients. Meningismus often takes hours to develop. Sentinel headache occurs in approximately a third of patients (there is significant variability between studies about this rate). Some patients are obtunded or unconscious: 10% of patients have seizures and 10-15% present in cardiac arrest.
