Diagnostic Accuracy of the Modified Evan's Blue Dye Test in Detecting Aspiration in Patients with Tracheostomy: A Systematic Review of the Evidence

Oropharyngeal aspiration (OPA) is a common occurrence in patients with tracheostomy. The modified Evan's blue dye test (MEBDT) is an easily administered bedside procedure for the assessment of tracheostomised patients. However, studies evaluating the diagnostic accuracy of the MEBDT reach conflicting results. Therefore, we conducted a systematic review to determine the overall accuracy of the MEBDT in detecting OPA in adults with tracheostomy. The search strategy incorporated searching electronic databases, checking reference lists and citations and retrieving unpublished data. Data of primary studies were extracted and examined by three independent reviewers. The assessment of the methodological quality of included studies was performed using the QUADAS-2 tool. Six studies met the inclusion criteria for this systematic review. The studies presented significant disparities in study design and patient characteristics. Furthermore, high discrepancies in the administration of MEBDT across studies were noted. Therefore, a meta-analysis was not considered appropriate. Sensitivity estimates varied widely across the studies (38-95 %), indicating that the MEBDT is unreliable in detecting OPA. However, the studies emerge with overall high specificity values, ranging from 79 to 100 %. This true negative rate suggests that the MEBDT correctly identifies patients without OPA. This review highlights the need for further research studies assessing the accuracy of the MEBDT in detecting aspiration in patients with tracheostomy, using a standardised and reliable procedure. Outcomes from such studies will update the current level of evidence in relation to the MEBDT and consequently define best clinical practice.

Diagnostic accuracy of the clinical feeding evaluation in detecting aspiration in children: a systematic review

The aim of this systematic review is to determine the diagnostic accuracy of clinical feeding evaluation (CFE) compared to instrumental assessments in detecting oropharyngeal aspiration (OPA) in children. This is important to support clinical decision-making and to provide safe, cost-effective, higher quality care. All published and unpublished studies in all languages assessing the diagnostic accuracy of CFE compared to videofluoroscopic swallowing study (VFSS) and/or fibre-optic endoscopic examination of swallowing (FEES) in detecting OPA in paediatric populations were sought. Databases were searched from inception to April 2015. Grey literature, citations, and references were also searched. Two independent reviewers extracted and analysed data. Accuracy estimates were calculated. Research reports were translated into English as required. Six studies examining the diagnostic accuracy of CFE using VFSS and/or FEES were eligible for inclusion. Sample sizes, populations studied, and CFE characteristics varied widely. The overall methodological quality of the studies, assessed with QUADAS-2, was considered 'low'. Results suggested that CFEs trialling liquid consistencies might provide better accuracy estimates than CFEs trialling solids exclusively. This systematic review highlights the critical lack of evidence on the accuracy of CFE in detecting OPA in children. Larger well-designed primary diagnostic test accuracy studies in this area are needed to inform dysphagia assessment in paediatrics.