As an undergraduate, you are highly likely to encounter a case of stroke in the medical examinations either in the long case format or short case format.
Making a diagnosis of stroke is not
difficult.
So, how do you suspect a patient has had a
stroke?
From history taking, the patient may
provide information regarding weakness affecting one side of the body i.e a
hemiparesis or a single limb i.e. a monoparesis. The patient may also have
cranial nerve involvement, presenting with diplopia, ptosis, facial asymmetry
or slurred speech. It is uncommon to get a patient with dysphasia or aphasia
for the undergraduate exams as this will impede history taking and physical
examination. Nevertheless, you may still encounter a patient with aphasia or
dysphasia if there is a shortage of neurological cases for the exams.
The
student will be expected to take necessary detailed history pertaining to the
right sided hemiparesis e.g. onset of weakness, progression of weakness, and
severity. From history taking it is difficult to determine if the patient has
had an ischemic stroke or a hemorrhagic stroke. However, in general, if the
patient complained of a sudden severe headache preceding or occurring
concurrently with the hemiparesis, it is always good to exclude hemorrhagic
stroke first. In real life practice, there are many cases of hemorrhagic stroke
where the patient presents with just sudden onset of limb weakness without any
headaches. The severity of the hemiparesis is not a good indicator to suggest
an ischemic event or a hemorrhagic event. There are cases of basal ganglia
hypertensive hemorrhages where the patient only has a mild hemiparesis of 3-4/5
whereas there are cases of left middle cerebral artery territory infarctions
with dense hemiparesis of 0-1/5.
Once you have decided that the patient has
a hemiparesis, you can make a diagnosis of a stroke. If the student has already
decided that this presenting complaint is likely due to an ischemic stroke,
then a reasonable differential diagnosis would be hemorrhagic stroke. It is
also applicable vice versa i.e. if the provisional diagnosis is a hemorrhagic
stroke, then the differential would be an ischemic stroke. Only a CT brain can
confirm the diagnoses.
Remember to explore other possible differentials as well. Ask about prolonged headaches, constitutional symptoms to suggest a brain tumour. Ask about stepwise deterioration of neurology e.g. history of facial asymmetry 10 years ago, then history of numbness affecting left leg 7 years ago, then history of bladder incontinence 3 years ago etc. This may suggest a possibility of a demyelinating condition such as multiple sclerosis. Also ask about recent head injury or trauma which may suggest a intracranial hemorrhage causing the stroke like symptoms. And also ask about fever, rashes, photophobia, neck stiffness or altered behaviour to suggest intracranial infection e.g. meningitis or cerebral abscess.
Once the student has established the
diagnosis and its differentials, the next step should be to explore the
aetiology. From history, ask about risk factors for the stroke i.e. hypertension
and its BP control, diabetes and its glycemic control, dyslipidemia and its
lipid control, history of ischemic heart disease, history of cigarette smoking
or chronic alcohol consumption/ abuse, connective tissue disorders (especially
if the patient is young, explore regarding anti phospholipid syndrome), medication history (compliance to medications as well as
whether patient is on anti-platelet therapy or anti-coagulation therapy) and history of head injury. It is
also good to get a detailed family history regarding cardiovascular risk
factors as conditions like diabetes, dyslipidemia, hypertension may run in
families. Also explore regarding dietary habits – fast food, oily food, high
salt diet, lots of processed foods etc. These aetiologies are supporting a diagnosis of ischemic/ hemorrhagic stroke. Remember to get history regarding aetiologies for the other differentials too if relevant to your patient.
Next step would be to explore complications that
may arise from the stroke. Ask about headaches, blurred vision which could
indicate raised intracranial pressure. Also ask about fever, cough, dyspnoea
and choking episode to suggest that the patient may have aspirated. Ask about
seizures as post stroke patients have tendency for seizures. Ask about falls
and physical injuries due to the physical limitations as a result of the
stroke. Ask about cognitive impairment or change in consciousness (very unlikely to get a demented or delirious or confused patient in the exam setting!).
Last but not least, explore about the
patients social history in more detail than usual. As stroke affects the
patient’s life very significantly, it is also good to know the patient’s
baseline functionality e.g. right or left handedness, occupation, breadwinner
or not, living at home with whom, hobbies, staying in what sort of house
(single storey versus multi storey and whether there is lift facility). All
this will give a rough idea on how the stroke may impact the patient’s life
once he is discharged from the hospital. The information obtained will help you
plan for long term management. For example if the patient is the sole
breadwinner of his family and he is no longer able to work, then you may offer
referral to social welfare for assistance. Another example would be if the
patient is right hand dominant and is a typist and loves to play tennis using
his right hand and he just suffered a stroke with right hemiparesis, then he
will benefit from occupation therapist referral to get him to adapt and learn
to adjust using his left hand while awaiting right hand to recover with rehab
(if at all possible).
Once the above mentioned has been settled, the student should go on to
complete the other components of history taking to ensure a complete history is
taken e.g. drug history, allergy history, surgical history, etc.
For physical examination (from head to toe),
Head:
Examine the Glasgow Coma Scale (GCS) and also orientation to time, place, person. Look for cranial neuropathy if it is suggestive from the history taking. Example, if the patient complained of facial asymmetry and slurred speech, then it is probably worth examining the facial nerve and the cranial nerves 9,10,12 properly. If upon general inspection there is eye deviation or ptosis, then a proper examination of the cranial nerves 3,4 and 6 is warranted. Otherwise it is unnecessary to do a FULL cranial nerve examination. Time is the limiting factor here! If the student managed to complete history taking within a short time frame, then perhaps when there is ample time, the student may still do a concise but full cranial nerve examination (The olfactory nerve is probably the least examined cranial nerve as it rarely appears for exams. So be smart when choosing which cranial nerve to examine). Look for risk factors for stroke: xanthelasma, arcus senilis, acanthosis nigricans (darkening and velvety like skin over the neck and flexure area). Also assess speech and nystagmus if history suggests cerebellar involvement.
UL:
Finger prick marks for diabetes mellitus. Nicotine stain over the finger nails. Tendon xanthomas. Upper motor neuron (UMN) signs affecting the weak arm: hypertonia, hyperreflexia. And also quantify the weakness using the MRC scale 0-5. Also check sensory deficits. Remember to check cerebellar signs as well if not yet done as part of the CN assessment. Important to check the blood pressure using sphygmomanometer as well.
LL:
Check for UMN signs affecting the weak leg: hypertonia, hyperreflexia, clonus, upgoing Babinski response. Quantify the weakness using MRC scale. And check for sensory deficits. Cerebellar assessment is also important if not yet done for UL or CN assessment. However if while assessing CN and UL and no cerebellar signs were detected, then it is not necessary to do cerebellar assessment for LL. Last but not least, ask the patient to walk to assess gait (do this only if the patient is able to walk. Do not cause a fall which may injure the patient).
CCE.
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