Clinical diagnosis in the acute phase of stroke – quite a challenge!

1. Clinical diagnosis in the acute phase of stroke – quite a challenge! Peter Sandercock Edinburgh

2. 11 am. Wife notices husband speech a bit odd and right hand clumsy. Is it a stroke?

3. Clinical diagnosis in the hyperacute phase (< 6hrs) • Need to be quick: ‘Time is brain’ • Need to triage in A&E as potential thrombolysis / IST 3 candidate if: • known time of onset • onset less than 5 hrs ago • definite focal neurological deficit still present (use FAST or LAPSS for screening) • NIHSS and OCSP classification if FAST +ve

4. Face Arm Speech Test (FAST) screening for paramedics/nurses Harbison. Stroke 2003;34;71-76;

5. ‘Acute brain attack with’ +ve FAST screen? Clinical assessment CT Scan Non-stroke pathology Stroke: Infarct, intracerebral bleed, SAH

6. Conditions that mimic acute stroke

7. Acute brain attack If NO evidence of ‘mimic, e.g.: fits/migraine Hypo/hyperglycaemia Other obvious metabolic cause DO CT Non-stroke pathology Subdural, tumour CT Scan Stroke: Infarct, intracerebral bleed, SAH

8. Non-stroke: bilateral subdural haematoma

9. Acute brain attack Exclude: fits/migraine Hypo-hyperglycaemia Other metabolic causes Non-stroke pathology: Subdural, tumour, etc CT Scan CT Normal or evidence of acute ischaemic stroke

10. Problems of clinical diagnosis within 6 hours of onset Do you need a neurologist? • Approximately 75% of conditions mimicking stroke are neurological How many of these can be identified by CT? • ~15% of non-stroke disorders (eg subdural) found by CT • rest diagnosed clinically/with other tests • CT < 6hrs of ischaemic stroke often normal If CT is normal • Often need stroke specialist or neurologist to confirm clinical diagnosis of stroke before thrombolysis: • avoid thrombolysis for migraine, focal epilepsy, ‘functional weakness’, ischaemic deficit after subarachnoid haemorrhage!

11. 2hrs ago right hemiparesis: thrombolyse? MRI DWI abnormal -but DWI not widely available CT Normal

12. Edinburgh ‘brain attack’ study Aim • Identify the ‘brain attack’ patients most likely to have acute cerebral ischaemia, potentially for thrombolysis Patients • 350 admissions (336 patients) • Age: 76.3 yrs (67 - 83) • Source of referral to stroke team: A&E triage in 92% • Time from onset to A&E: 4.7 hrs (2 - 14) Hand PJ. Stroke 2006; 37: 769-775.

13. Primary analysis • ‘Thrombolysis eligible brain attacks’ (n=241) = definite stroke, probable stroke, definite TIA • Mimics (n=109) = definite non-stroke, all possible stroke/TIA with a plausible non-stroke explanation

14. Pointers to ‘rt-PA/ist3 eligible:’ past history Pointer to ‘more likely NOT for thrombolysis/IST3’ Pointer to ‘more likely eligible’

15. Pointers to ‘rt-PA/ist3 eligible:’ History of this event

18. NIHSS training website http://asa.trainingcampus.net/uas/modules/trees/windex.aspx Note: works best with a high-speed (broadband) connection!

22. Clinical pointers: summary To ‘likely eligible for thrombolysis/ist3’ • Known time of onset • Abnormal vascular signs (AF, PVD) • Unilateral neurological signs • Can assign an OCSP classification • Increasing NIH score To ‘likely not eligible’ • prior cognitive impairment • LOC early • seizure • can walk now ( too mild)

23. Can you diagnose ‘acute ischaemic stroke suitable for thrombolysis’ without DWI MR? Yes, if: • The time of onset of stroke symptoms is known precisely • You have an experienced stroke physician/stroke neurologist able to see the patient urgently in A&E or at CT scan room • Urgent non-contrast CT scan is interpreted by someone with expertise in acute stroke CT • -> MRI not essential; its place in routine acute stroke care yet to be determined