Cough reflex testing in acute stroke: A survey of current UK service provision and speech and language therapist perceptions

Background: Silent aspiration (SA)-airway entry of food, drink or other material without a cough response-is common post-stroke. Clinical swallowing examination misses up to 40% of dysphagic patients with SA. This may put these patients at risk of aspiration pneumonia, prolonged length of hospital stay and increased healthcare costs. After stroke, the laryngeal cough reflex is frequently impaired with significant relationships between pneumonia rates and reduced cough strength and sensitivity. There has been a significant amount of recent interest in cough reflex testing (CRT) as a potential means to improve clinical identification of patients at risk of SA. However, there is a lack of consensus regarding the methodology and protocols for use of CRT with widely varying outcomes reported in the literature.

Aims: To provide an overview of current practice in the UK with regards to clinical use of CRT by speech and language therapists (SLTs) in acute stroke settings and to explore the perceptions regarding its potential application in clinical dysphagia management and the barriers and facilitators associated with adopting CRT in clinical practice.

Methods & procedures: A cross-sectional web-based survey was developed, piloted and delivered. The survey targeted all UK-based SLTs working in acute stroke settings.

Outcomes & results: A total of 129 SLTs with varying levels of experience of CRT from all regions of the UK responded. Only four SLT services in the UK were reported to be currently using CRT clinically with acute stroke patients. A total of 29% of respondents who were not using CRT were considering introducing CRT into their service's dysphagia protocol. Variation was reported in the procedures and protocols. Overall, users reported improved confidence in the clinical detection of SA and felt that the introduction of CRT had improved their patient-related outcomes. Issues included difficulties procuring citric acid, implications for SLT time (including service set-up and delivery of CRT) and restricted access to instrumental assessments.

Conclusions & implications: This survey gives valuable insight into the current practice and perceptions of SLTs in the UK working in acute stroke settings in relation to CRT. It highlights discrepancies between reported approaches and recommendations from existing guidelines and validation studies. The variation in responses indicates a need to develop a consensus statement and further research to guide practice. What this study adds What is already known on the subject CRT is gaining popularity as a screening tool for the clinical identification of SA with acute stroke patients. However, there is a lack of consensus in the literature regarding the methodology and protocols with widely varying outcomes. Further work needs to be done to standardize its use, especially if it is to be incorporated into dysphagia protocols for use in the acute stroke setting. What this paper adds to existing knowledge This survey of SLTs working in acute stroke settings highlights variability in practice in CRT service delivery in the UK, reflecting findings from the existing CRT literature. What are the potential or actual clinical implications of this work? The findings of this study support the need for further research relating to clinical screening tests for SA and standardization of methodology and protocols for CRT use if its use is to be continued clinically.

Keywords: cough reflex testing; dysphagia; silent aspiration; speech and language therapy; stroke; survey.