1. Risk of stroke at 3 months6 Expected Strokes at 3 months
The Clinical Effectiveness of an Acute Medicine Transient Ischaemic Attack Service
Dr Padmini Sastry & Dr Ben Mearns
Department of Acute Medicine, Surrey & Sussex Healthcare NHS Trust
Background
Transient Ischaemic Attack (TIA) is a medical emergency with a high risk of stroke.
There is a body of evidence clearly showing that the risk of subsequent stroke following TIA may be reduced by as much as 80% with acute assessment and treatment in “one-stop” clinics1,2. National clinical guidelines are also extremely clear on the urgency of care and resultant favourable outcomes3,4,5. 
Our TIA service in 2008 operated from two clinics per week in a standard referral and appointment manner. Therefore assessment, investigation and treatment could take several weeks to complete.
 Our aim was to assess the clinical effectiveness of a one-stop Acute Medical Unit (AMU) based TIA service.
ABCD2 SCORE
Number of Patients
Risk of stroke at 3 months6
Expected Strokes at 3 months
Observed Strokes at
3 months
0-3 42
3.1%
1.302
4-5 56
9.8%
5.488 2 6+ 13
17.8%
2.314
Table 1: Expected number of strokes calculated from ABCD2 risk score and actual number of observed strokes 3 months after TIA clinic appointment.
Methods
The AMU based TIA service started in and provides next working day acute care for all TIA patients, including performance of all necessary investigations within 24 hours. The clinics operate Monday to Friday for all patients referred the previous day with review of both high (≥4) and low (0-3) ABCD2 risk patients.
In order to improve the service we:
Created standardized referral forms for GP and other hospital doctors
Taught GPs and other clinicians about our service
Worked with the Surrey Stroke Network on training days
Created a single bleep holder to take all TIA and Stroke related calls 24 hours per day, 7 days per week
Worked closely with Radiology to obtain instant access to CT and Carotid Doppler slots on a needs related basis
An Acute Medicine ambulatory pathway (AMap) has been created to ensure access without delay and that care is patient-centred and mapped to current best practice guidelines3,4,5. Fasting bloods tests, ECG, CT brain scan and Carotid Doppler (if indicated) are performed the morning of the clinic. These results and ensuing treatment are discussed with the patient following Consultant review in the afternoon (figure 1 & figure 2).
An audit of patients seen in the AMU based TIA clinics at East Surrey Hospital between November 2008 and November 2009 was conducted to assess outcome. Letters were sent out to GPs and of 243 patients seen written feedback was obtained for 168 (69%) and cross-referenced with hospital records.
Chart 1: Number of expected strokes at 3 months from the TIA clinic compared to the number of observed strokes
Conclusion
The Acute Medical Unit can be an appropriate environment to operate a one-stop urgent TIA service with good clinical outcomes.
Acute Medical Teams can be valuable contributors to Stroke & TIA care from a service that operates 24 hours a day, 365 days a year.
Our service relies on close partnership working with the Acute Medical and Stroke Teams, specialist training for all involved and a robust clinical governance structure.
For patients who have an alternative medical diagnosis (33% in our audit) the service is truly one-stop as cases can be worked up immediately and efficiently without the need for further referral. This makes the service truly patient-centred rather than condition-centred.
Our future now lies with the development of a 7 day service and work is ongoing to move towards an MRI based imaging system with off-site reporting to allow for this welcome change.
Outcomes
Our analysis revealed that 111 (66%) of the GP letters received were for patients with clinical diagnoses of TIA and probable TIA.
Of these patients 2 had strokes within 90 days of clinic suggesting a stroke rate of 1.8%, comparable to that reported in the EXPRESS study1. Both patients had “high risk” ABCD2 scores of 4 or more. No strokes were observed in patients thought not to have had a TIA.
Using the ABCD2 tool as validated by Johnson et al6 9 strokes would be expected in this group rather than the 2 observed (table 1 & chart 1).
Of high risk patients 73% were reviewed within 24 hours of referral, 72% had CT scans in clinic and 66% had investigations and treatment within 24 hours. 
References
Rothwell PM, Giles MF, Chandratheva A et al. Effect of urgent treatment of transient ischaemic attack and minor stroke on early recurrent stroke (EXPRESS study): a prospective population-based sequential comparison. Lancet 2007;370(9596):1432–1442.
Lavallee PC, Meseguer E, Abboud H et al. A transient ischaemic attack clinic with round-the-clock access (SOS-TIA): feasibility and effects. Lancet Neurology 2007;6(11):953–960.
STROKE National clinical guideline for diagnosis and initial management of acute stroke and transient ischaemic attack (TIA). Royal College of Physicians of London, 2008.
STROKE National clinical guideline for diagnosis and initial management of acute stroke and transient ischaemic attack (TIA). NICE, 2008.
National Stroke Strategy, Department of Health, 2007.
Johnston SC, Rothwell PM, Nguyen-Huynh MN et al. Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack. Lancet 2007;369(9558):283–292.
Please send all correspondence to Dr Padmini Sastry, Department of Acute Medicine, Surrey & Sussex Healthcare NHS Trust, Canada Avenue, Redhill, Surrey RH1 5RH or