Swansea Stroke Scale (SSS) for bedside assessment of Stroke sufferers
Research type
Research Study
Full title
Swansea Stroke Scale (SSS) for bedside assessment of Stroke sufferers by non-specialists- a pilot study
IRAS ID
341200
Contact name
Manju Krishnan
Contact email
Sponsor organisation
Swansea Bay University Health Board R&D department
Duration of Study in the UK
0 years, 6 months, 1 days
Research summary
Summary of Research
The study is developing a new bedside stroke assessment form called the Swansea Stroke Scale (SSS) that can be adopted by anyone caring for a stroke sufferer. This is an observational study conducted on the Acute Stroke unit (ward F), Morriston Hospital, Swansea Bay University Health Board. The study aims to validate the SSS by implementing this on new stroke admissions to the ward, undertaken by ward staff including junior doctors below the specialist training grade, Physician associates, registered nurses and healthcare support workers, all of whom are generalists, involved in providing the day to day care on the stroke unit.
The stroke scales that are currently in use are either non-specific to stroke related deficits or are to be adopted by someone with specialist training.
Most of our ward staff are generalists and hence adopting a new stroke scale would help us monitor stroke related deficits regularly in stroke sufferers. This will also help detect a clinical change, so that appropriate action can be undertaken without delay to help towards a recovery.Summary of Results
Swansea Stroke Scale (SSS) for bedside assessment of Stroke sufferers by non-specialists- a pilot study M Krishnan, I Cheung, R Thomas, S Bain
Background: Our stroke survivors on acute and rehabilitation units are regularly assessed and looked after by non-specialist staff including Registered Nurses (RN), Healthcare support workers (HCSW), Physician associates (PA) and junior doctors below the level of internal medicine training level 3 (IMT 3). We wanted to create a simple bedside tool that they can use to detect a neurological change after admission with an acute stroke. Any change in neurological presentation is time-critical and a failure to detect an acute decline can result in a catastrophic outcome. The current stroke specific scales such as the National Institute of Health Stroke Scale (NIHSS) requires specialist training and knowledge of neurological examination, which is outside the competency of this staff group. Scales such as the Glasgow Coma Scale (GCS) is not specific for stroke related disability. Daily NIHSS assessments by specialist staff is not practical considering the staffing challenges we are facing and hence the plan to up-skill non-specialist staff to be able to detect a clinical change after the index stroke event.
Aim: We developed the Swansea Stroke Scale (SSS), a simple bedside assessment tool that can be used without prior training. This was formulated by collating the usual bedside assessments pointing to the aggregated neurological disability having suffered the stroke. Yet, the scale has to be understood by those without any specialty training, including our HCSW. The clinical findings required to calculate SSS are derived by observation at the bedside and does not require a detailed neurological examination (which will be outside the competency of most non-specialist staff). A pilot study was conducted after receiving approval by the Research Ethics Committee (REC) recruiting 20 acute stroke admissions, each undergoing the SSS score four times in the first 7 days. Objective of the pilot phase was to test the use of the SSS by non-specialists on acute stroke admissions to a tertiary hospital, reviewing the correlation of this to the existing scores such as the NIHSS and the modified Rankin score (mRS) and the inter-rater agreement of the score performed at 24-36 hours of admission by two independent assessors without any prior consultation to each other’s assessment results. A staff survey at the end of the pilot study was undertaken to determine the ease and time taken for completion for the SSS.
SSS comprises five parameters for the assessment at bedside reflecting the clinical deficits and their impact on the overall situation, sight, speech, oral intake and movement. The categories used here are simple and easy to be used by anyone caring for a stroke sufferer, with a maximum score of 20, minimum of 5. The score adds points according to the deficits present.
1. Situation (maximum 4 points): Awake and chatty (1 point), Sleepy, but easily woken up to voice (2 points), Drowsy, not waking to voice but responding to physical stimulus (3 points), Unresponsive to recurrent vocal and physical stimulus (4 points).
2. Sight (maximum 4 points): Looking around (1 point), not seeing objects/people on one side (2 points), Gaze fixed to one side (3 points), Eyes closed (not opening despite vocal or physical stimulus) (4 points).
3. Speech (maximum 4 points): Able to follow and talk normally (1 point), Able to follow and talk but slurred speech (2 points), Able to follow, unable to talk or Unable to follow, talking random words/sentences (3 points), Unable to follow and unable to talk/ mute (4 points).
4. Oral intake (maximum 4 points): on normal diet (1 point), on amended diet orally (2 points), on NG (Nasogastric) feed or PEG (Percutaneous Endoscopic Gastrostomy) feed mainly (3 points), No feeding options (nil by mouth with no NG or PEG) (4 points).
5. Movement (maximum 4 points): Walking independently/ moving all 4 limbs (1 point), Walking with aids/support, mild arm/leg weakness (2 points), Steady transfer, moderate arm/leg weakness (3 points), Hoisted/bed bound, severe arm/leg weakness (4 points).
Methodology: This is a prospective observational cohort study. 20 participants were recruited during the study period. Inclusion criteria was any new admission with acute stroke over the age of 18 years to Swansea; excluded those <18 years and those with stroke onset more than 7 days prior to the admission. Each participant had the SSS scoring performed four times, once on admission to the stroke unit, twice at 24-36 hours (repeated by a second independent assessor) to assess the inter-rater agreement of the SSS using kappa statistic. A fourth SSS score undertaken at day 7 or earlier if the patient is discharged from the acute site or has a terminal decline. The 60 SSS forms (20 at baseline, 20 assessed by assessor 1 at 24-36 hours and 20 at day 7 or earlier) collected were used to measure intra-class correlation with the NIHSS and mRS score after standardisation. As NIHSS scores were also used to group strokes into different levels of severity, optimum SSS cut off points for classifying stroke severity were determined using the Area under the curve analysis based on these NIHSS categories. The resultant SSS categorisation was compared with NIHSS categorisation by kappa. Staff survey using non-validated questionnaire at the end of the study was undertaken by the study research nurse to test the ease and time taken to undertake each SSS score as well as any feedback from staff prior to proceeding with the main study.
Results: 22 participants were consented of which 2 were excluded as they had moved from the acute stroke unit in less than 24 hours. Of the 20 included in the study, age range was 59-94, 65% were men, majority (95%) were admitted with ischaemic stroke with 30% in the minor stroke category (NIHSS 1-4), 55% moderate (NIHSS 5-15), and 15 % severe (NIHSS 16 and above) stroke. 45% were discharged home by day 7, 15% died in the first days, and the remaining 40% were still hospitalised either on acute site or the rehabilitation unit by day 7. Relative declaration forms were completed in those who were unable to consent for the study.
Reliability (SSS vis-à-vis other scales): Intra class correlation (ICC) with 95 % confidence interval for SSS and NIHSS was 0.72 (95 % CI 0.57-0.82, p<0.001) revealing moderate reliability, whilst the same for SSS against mRS was 0.56 (95% CI 0.36-0.71, p<0.001).
Area under Curve analysis was performed to examine the best combination of sensitivity and specificity of stroke severity by SSS against the NIHSS with results revealing Mild to be a score of 6 or below, Moderate score of 7 to 12 and Severe score to be 13 or above, with a kappa of 0.61 for the inter-rater agreement (substantial agreement) with NIHSS categorisation.
Time taken to complete the SSS score as obtained from staff survey was between 1-2 minutes and 3-5 minutes with all staff participants rating the SSS as ‘easy’ to complete.
Conclusion: The newly developed Swansea Stroke Scale for non-specialist staff was feasible to use in an acute stroke setting with staff survey revealing it to be easy to use and not time consuming (< 5 minutes). It shows good correlation with the NIHSS undertaken by specialist staff. A main study is planned to be undertaken to analyse its reliability and inter-rater agreement further before we can recommend this scale for clinical use by non-specialist staff looking after stroke survivors.REC name
Wales REC 5
REC reference
24/WA/0109
Date of REC Opinion
21 May 2024
REC opinion
Further Information Favourable Opinion