Spotlight on Stroke

Stroke Training Resources and Opportunities

American Stroke Association International Stroke Conference

Feb. 24-26, 2010

Stroke Management Issues for Hospitalists

The management of stroke is an emergency. That theory is best reflected in the maxim “time is brain,” says Jose Biller, MD, a neurologist at Loyola University Health System in Chicago. “Appropriate treatment begins with correct diagnosis,” he says. “Misdiagnoses of strokes are not uncommon but may have serious consequences.”

Eighty-seven percent of strokes are ischemic (a blood clot blocking a vessel in the brain). The other 13% are hemorrhagic strokes or subarachnoid hemorrhages. The distinction is critical, because IV t-PA is contraindicated when there is evidence of bleeding in the brain. For the most part, it’s tough to tell at first glance if a patient has suffered an ischemic or hemorrhagic stroke. A brain scan, typically a noncontrast computed tomography (CT) scan, is needed to rule out intracerebral hemorrhage.

IV t-PA can reverse the disabling effects of stroke if administered within a narrow therapeutic window of opportunity. National stroke treatment guidelines call for IV t-PA to be administered within three hours of the known onset of symptoms. The clock starts at the time the patient was last seen normal. Intravenous t-PA is not recommended outside the time window or for such contraindications as recent major surgery, stroke, or serious head trauma within the past 30 months, history of intracranial hemorrhage, seizures at onset of symptoms, or arterial puncture at a noncompressible site within seven days.

IV t-PA can have serious side effects, but it remains the gold standard of stroke treatment within the suggested time allotment. Recent research points toward widening the time window for IV t-PA from three hours to 4.5 hours. The multinational, double-blind European Cooperative Acute Stroke Study (ECASS III), published in the Sept. 25, 2008, issue of the New England Journal of Medicine, concluded that t-PA is still beneficial up to 4.5 hours after onset of symptoms, although “sooner is better and every minute counts.”7

This finding eventually will make its way into formal guidelines, Dr. Josephson says, and some hospitals already have adopted the 4.5-hour window for IV t-PA treatment.

In May 2008, an AHA/ASA advisory recommended that IV t-PA be provided up to 4.5 hours after known onset of a stroke, unless the patient is older than 80, takes oral anticoagulants, has an assessed National Stroke Scale score greater than 25, or presents a history of both stroke and diabetes.8 In those cases, AHA/ASA recommends sticking to the three-hour ceiling.

Patrick Lyden, MD, a neurologist at the University of California at San Diego School of Medicine, noted in a September 2008 New England Journal of Medicine editorial that thrombolytic therapy can restore neurological functions if given early enough, and “has stood the test of time, shown benefit in serial community registries on multiple continents, and received approval by every major regulatory authority in the world.”9

In fact, IV t-PA is such a powerful tool for reversing stroke’s effects that the bigger question is, why is it used only for an estimated 2% to 10% of stroke patients? According to data presented at an international stroke conference in February, 64% of U.S. hospitals had not provided any IV t-PA treatments within the prior two years.10 Researchers concluded that some patients get medical help too late, but some hospitals and physicians are uncomfortable administering t-PA, and others lack sufficient protocols for responding quickly with assessment and treatment.

Hospitalists need to understand the medical management of patients who do not qualify for t-PA, approaches which have their own time windows, Dr. Josephson says. Intra-arterial administration of the therapy is supported up to six hours after the onset of stroke, while mechanical embolectomy—physically removing the clot—is recommended for as many as eight hours after onset. Newer systems for performing mechanical embolectomies include the Merci Retrieval System and the Penumbra System.

Past eight hours, stroke treatment involves appropriate choice and intensity of anti-coagulant (heparin, warfarin) and antiplatelet treatments. According to the recent PRoFESS trial, the most common antiplatelet treatment choices, clopidogrel and dipyridamole with aspirin, were found to be equal in efficacy.11

Recognizing the patients who present in the ED with evidence of TIA is critical to treatment options; many are at high risk for a full-blown stroke within the next 48 hours and should be admitted for aggressive management.12 The ABCD Score has been shown to predict which recent TIA patients are at higher risk of stroke, and thus are in need of immediate evaluation to optimize stroke prevention.1,13 “The idea that TIA and stroke are different diseases is giving way,” Dr. Josephson says. “Conceptually, they are the same disorder.”

Other treatment issues include DVT prophylaxis, identifying potential sources of embolisms, and choice of echo exam. Managing blood pressure could include permissive hypertension as high as 220/120 immediately post-stroke in patients who did not receive t-PA, or 180/105 following t-PA, then returning the blood pressure back to normal in a slow and safe manner.14—LB