Stroke Diagnosis and Management Flashcards
Your presumptive or working diagnosis in a patient who presents with the abrupt onset of focal neurologic symptoms and signs will be stroke. However, keep in mind the broad differential that we discussed in the prior self learning session. Following good clinical emergency practice your first task is to:
check and stabilize all vital signs.
You should quickly collect a history of the event with special attention to time of symptom onset which is best determined by asking the patient or family when the patient was last observed to be normal. You should ask questions about symptom progression, whether a headache is present and if so how severe. From this history you should formulate an anatomical diagnosis, i.e. what brain region is involved and what is the vascular supply.
Information on the Past Medical History, Family History, and Social history will provide valuable information about risk factors for stroke.
You should then perform a rapid but thorough medical and neurological exam. Information gathered from the medical exam will help determine the etiology of the stroke.
You are particularly interested in heart rate and rhythm, blood pressure in both arms, the presence or absence of a carotid bruit, and the peripheral vascular exam.
The neurologic exam will help clarify the anatomic diagnosis and vascular territory that is involved. At this point you should be asking yourself is this a stroke or a stroke mimic. If it is a stroke is it ischemic or hemorrhagic. What is the vascular territory? What is the etiology?
Diagnostic work-ups for any medical or neurological disease should never be cook booked but there are standard laboratories that you will order in most patients presenting with stroke symptoms. This table lists what are considered routine laboratory tests in stroke patients
This table presents additional laboratory tests that you may consider ordering depending on various factors present or absent in the patient
The radiologic evaluation of a stroke patient is extremely important. This list includes the types of tests that you may request. The selection of which tests to order will once again depend on factors either present or absent in your patient.
This is a slide of a severe right MCA stroke with involvement of the entire MCA territory. One must understand at what time after stroke onset that brain imaging begins to show evidence of the stroke. Head CT scans begin to detect evolving infarcts within approximately 6-12 hours and thus the CT scan is not a good imaging tool to detect an early ischemic stroke. However, the head CT scan is highly sensitive to hemorrhage and thus is indicated in all patients presenting with stroke symptoms to rule out hemorrhagic stroke.
This slide presents the CT scans (upper panel), MRI Diffusion Weighted Images (middle panel), and the MRI Fluid Attenuated Inversion Images (lower panel) of a 62 year old man with an acute onset of aphasia and right hemiparesis.
The scans were obtained between one and two hours after symptom onset.
Note that the CT scan appears entirely normal. The MRI FLAIR image shows only a small area of the left parietal lobe with early hyperintensity (yellow arrow). However, the MRI DWI image reveals a large area of hyperintensity (yellow arrows). Thus, neither the CT scan nor the MRI FLAIR images are able to detect the full extent of stroke that is evolving during the early hours after symptom onset but the DWI is very sensitive to these early ischemic changes in the tissue.
These figures present examples of ultrasound images of the carotid arteries. The upper left and middle figures present B-mode ultrasound images of the carotid artery to be compared with a digital subtracted arteriogram (DSA) in the upper right image. Note the narrowing at the origin of the internal carotid artery on the DSA and similar narrowing on the two B-mode ultrasound images. The Doppler image below records the wave form of blood moving through the carotid artery.
This is an example of the intracranial vasculature obtained with magnetic resonance imaging.
This Netter slide demonstrates the interventional neuroradiographic methods for catheter placement via the femoral artery and the injection of contrast dye to create digital subtraction images of extra- and intra-cranial blood vessels. The images on the right demonstrate a DSA in a patient with occlusion of the MCA prior to (left) and after (right) thrombolysis with tissue plasminogen activator (tPA). Note the absence of MCA vessels in the left figure and the presence of the MCA (arrow) vessels after lysis of the clot (right figure).
What is the acute tx of stroke?
Ø Treat with intravenous tPA if <4.5 hr from symptom onset and patient meets other strict criteria
Ø Treat with intraarterial tPA is < 6.0 hr from symptom onset and patient meets other strict criteria
Ø Retrieve clot with intra-arterial retrieving device if < 8 hr from symptom onset andnpatient meets other strict criteria
Prophylaxis remains the most effective method for dealing with stroke. What is involved?
Medical treatment for hypertension, hyperlipidemia, and diabetes are the mainstay of stroke prophylaxis. The addition of an antiplatelet agent, e.g. aspirin, in cases of atherosclerosis or warfarin in instances of cardiogenic emboli significantly reduce the recurrence of ischemic stroke.
The following series of slides describe an actual case. Please review the next series of slides and we will use these during our contact hour to discuss the diagnostic work-up of a patient presenting with acute focal neurologic symptoms and signs.
