Impact of carbonation on neurogenic dysphagia and an exploration of the clinical predictors of a response to carbonation

Abstract

Background The need for effective compensatory strategies in neurogenic dysphagia management has led to the exploration of sensory enhancement strategies (SES), such as carbonated liquids. Despite some positive findings, evidence related to the efficacy of carbonation as an SES is limited. Aims To determine if carbonated thin liquids reduced dysphagia symptoms and to explore clinical factors associated with response to carbonation. Methods & Procedures Participants (n = 29) with neurogenic dysphagia demonstrating deep penetration or aspiration on thin liquids during videofluoroscopic swallow studies (VFSS) completed a set protocol: discrete sips of non‐carbonated thin fluids (DS‐NC) followed by discrete sips of carbonated thin fluids (DS‐C) and then consecutive sips of carbonated fluids (CS‐C). The impact of carbonation was identified through changes to swallow physiology (videofluoroscopy dysphagia scale—VDS) and depth of airway compromise (penetration‐aspiration scale—PAS). Demographic variables including genetic taste type, cranial nerve function and key results from the VDS were examined for association with carbonation response using both individual parameter analysis and exploratory cluster analysis. Outcomes & Results Significant (p < 0.05) improvements in PAS scores were noted in DS‐C and CS‐C conditions compared with DS‐NC. Total VDS score was also significantly (p < 0.05) reduced (i.e., improved function) in the DS‐NC condition. Individual variability in response to carbonation was noted and no clear clinical factors associated with carbonation response in the current set of parameters were identified. Conclusion & Implications Findings support that carbonated thin fluids sometimes result in neurogenic dysphagia symptom reduction. However, identifying the clinical characteristics of patients who may benefit from trials of carbonation needs further investigation.

Effects of carbonation of liquids on penetration–aspiration and residue management

“…Only one study to date attempted to explore factors that can predict which patients will benefit from carbonation. Turkington et al attempted to identify predictors for response to carbonation in a neurogenic dysphagia patient group and found no significant predicting factors [20]. We hypothesized that carbonation, being a SES, will be found most beneficiary in patients who have impairments in their sensory pathways.…”

“…Carbonation has been explored as a SES with effects on multiple sensory pathways, including mechanical perception of the CO 2 bubbles, nociception and chemical perception of carbonic acid, a byproduct of CO 2 metabolism [12][13][14]. Its palatability has made it an easily applicable SES in the clinical setting [9,[15][16][17][18][19][20]. Studies exploring the effects of carbonation on swallowing physiology have shown conflicting results, probably due to methodological variability [21].…”

“…Studies examining the effects of carbonation on dysphagia have shown that benefit from carbonation is not uniform for all patients [15][16][17][18][19][20]. Patients with neurogenic dysphagia are the main population which showed benefit from carbonation [17][18][19][20]. Only one study to date attempted to explore factors that can predict which patients will benefit from carbonation.…”

Impact of Sensory Stimulation on Pharyngo-esophageal Swallowing Biomechanics in Adults with Dysphagia: A High-Resolution Manometry Study

“…There is preliminary evidence to support the use of a cold, sour and carbonated bolus to optimize swallowing. However, most research to date focuses on swallow safety and efficiency as well as temporal swallowing measures based on VFS (11)(12)(13)(14)(15). While VFS can provide some objective swallowing measures, it requires radiology and barium has been found to suppress taste intensity and palatability (16).…”

Carbonation as a sensory enhancement strategy: evidence for clinical implementation

“…There is some description of limitations of secondary outcome measure in the published article (Turkington, Ward, Farrell & Wall, 2019). The VDS was used as a pragmatic framework for clinicians to agree definitions across several qualitative constructs.…”