The Exact Science of Stroke Thrombolysis and the Quiet Art of Patient Selection

Joyce S. Balami; Gina Hadley; Brad A. Sutherland; Hasneen Karbalai; Alastair M. Buchan


Brain. 2013;136(12):3528-3553. 

In This Article


History taking and prompt structured assessment are crucial components of effective acute stroke management. The clinician should attempt to identify objective signs (such as eye deviation, either through observation or on subsequent imaging) (Simon et al., 2003) and apply quantitative metrics to rapidly make a correct diagnosis and determine a proper course of action. Key metrics include time of onset, age, and baseline blood glucose, blood pressure, stroke severity—as measured by National Institute of Health Stroke Scale (NIHSS)—and CT changes, as measured by the Alberta Stroke Programme Early CT Score (ASPECTS).

Time of onset should be established as precisely as possible, either from patient history or eyewitness accounts, taking special notice of sudden onset focal neurological defecits, such as disruptions of regularly scheduled activities like cooking or shopping, or abruptly becoming unable to finish reading a page or watching a television programme, or even, in today's social media-savvy world, acute onset 'dystextia' (garbled text messages) (Ravi et al., 2013).

Neurological deficit can be assessed using the NIHSS, a widely used validated scale, which provides a quantitative assessment of stroke severity and is highly reproducible (Kothari et al., 1995a, b). The NIHSS can also be used to chart stroke progression and response to therapy, as well as being a useful communication tool among the stroke team. It has been used to predict both short and long-term outcome in acute ischaemic stroke patients: patients with a NIHSS >20 have only a 4–16% chance of good outcome at 1 year, increasing to 60–70% in those with a NIHSS <10 (Adams et al., 1999; Kwiatkowski et al., 1999), recently reconfirmed (Kwakkel et al., 2010). However, limitations of the NIHSS include lack of detailed assessment of cranial nerves, and low scores for disabling infarctions involving the brainstem or cerebellum (Kasner, 2006). Other commonly used stroke scales include the European Stroke Scale (Hantson et al., 1994), Canadian Neurological Scale (Cote et al., 1986) and the Scandinavian Stroke Scale (Scandinavian Stroke Study Group, 1985), but we favour the NIHSS because it is the most widely used in clinical trials.

Reduced level of consciousness and coma are difficult to assess using existing neurological deficit scores, and coma was an exclusion criterion in the original intravenous thrombolysis trials, but there may be a role for interventional therapies in established vertebrobasilar artery thrombosis.