Stroke and TIA

Abstract

Transient ischemic attack (TIA) is defined as a transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction. A stroke occurs with progression to acute infarction in this context.

Patients with ischemic stroke usually present with sudden onset of hemiparesis, facial droop, hemisensory loss, aphasia, dysarthria, hemianopsia, ataxia, diplopia, or vertigo. These patients should be assessed promptly because there is a therapeutic window of 4.5 h for giving intravenous thrombolysis with tissue plasminogen activator (t-PA). Hemorrhagic stroke typically presents with sudden severe headache, focal weakness, and usually pronounced altered mental status.

Initial stabilization and evaluation of the patient should be expeditious and systematic especially since outcome is so time sensitive. It is important to avoid aggressive lowering of blood pressure that may precipitate or extend cerebral infarction. Obtaining the exact time of onset of symptoms is of paramount importance. The critical aspects of the focused examination are guided by the NIH stroke scale. Emergency lab work includes CBC, BMP, and a coagulation panel. Emergency neuroimaging includes a brain CT scan/CT angiogram +/− brain CT perfusion scan, and stroke protocol MRI brain scan. t-PA is usually withheld if infarct volume estimated by early changes on CT or MRI is more than 1/3 the MCA territory especially if between 3 and 4.5 h since symptom onset.

If the patient’s symptoms are persistent and significant, the onset was less than 4.5 h ago, and there is no history of seizure activity and no suspicion of intracerebral or subarachnoid hemorrhage, I.V. thrombolysis should be given unless otherwise contraindicated. Intra-arterial t-PA may be used in some centers but only in carefully selected patients who have missed the 4.5-h window.

Blood pressure should be carefully monitored after giving thrombolysis and antihypertensive treatment by algorithm administered if confirmed readings of >180/105 mmHg.