4
Diagnosis
Table 3. Immediate Diagnostic Studies: Evaluation of a
Patient With Suspected Acute Ischemic Stroke
All patients
Noncontrast brain CT or brain MRI
Blood glucose
Oxygen saturation
Serum electrolytes/renal function tests
a
Complete blood count, including platelet count
a
Markers of cardiac ischemia
a
Prothrombin time/INR
a
Activated partial thromboplastin time
a
ECG
a
Selected patients
TT and/or ECT if it is suspected the patient is taking
direct thrombin inhibitors or direct factor Xa inhibitors
Hepatic function tests
Toxicolog y screen
Blood alcohol level
Pregnancy test
Arterial blood gas tests if hypoxia is suspected
Chest radiography if lung disease is suspected
Lumbar puncture if subarachnoid hemorrhage is suspected
and CT scan is negative for blood
Electroencephalogram if seizures are suspected
a
Although it is desirable to know the results of these tests before giving IV recombinant tissue-type
plasminogen activator, fibrinolytic therapy should not be delayed while awaiting the results unless
(1) there is clinical suspicion of a bleeding abnormality or thrombocytopenia, (2) the patient has
received heparin or warfarin, or (3) the patient has received other anticoagulants (direct thrombin
inhibitors or direct factor Xa inhibitors).