Effects of Carbonation on Swallowing: Systematic Review and Meta-Analysis

Exploring the impact of bubble type on sensory stimulation in drinks

This study explores the impact of various types of carbonation on sensory stimulation in the mouth, salivary secretion and the neurotransmitter substance P (SP), as well as body responses such as heart rate (HR) and Galvanic Skin Response (GSR). Three types of carbonation (one made using a soda machine, another carbonated with a gasifier, and the last commercial sparkling water) were used to produce different bubbles resulting in distinct sensory characteristics assessed by a trained panel. The impact of carbonation was measured by recording changes in salivary flow rate, SP levels, salivary secretory immunoglobulin A (SIgA), HR, and GSR in fifteen healthy participants. The results showed that the bubble type only affected the sensory perception of carbonation. Regardless of bubble type, carbonation increased salivary flow rate and SP values, SigA and HR. These characteristics are being sought to improve treatments for dysphagia or dry mouth. Therefore, these findings highlight the potential therapeutic application of carbonation in these situations.

Effect of carbonation and thickening on voluntary swallow in healthy humans

BACKGROUND

Liquid modification is a widely established strategy of treatment for patients with dysphagia. The modification of liquid particularly by thickening or carbonation is a common approach to promote safe swallowing.

OBJECTIVE

This study sought to investigate how carbonated and/or thickened water modulates swallowing behaviours during swallowing in healthy young individuals.

METHODS

Thirty-one healthy volunteers (9 men, 22 women; mean age ± standard deviation [SD], 25.7 ± 6.2 years) were instructed to swallow 20 mL of water, carbonated water and carbonated juice with and without added thickening agent. Electromyograms (EMGs) of the suprahyoid (S-hyo) muscles were recorded to evaluate swallowing behaviours. Obtained S-hyo EMG bursts was analysed using the following outcome parameters: onset latency, the time between swallowing que to onset of EMG burst; rising time and falling time, defined as the time between onset and peak, and between peak and offset, respectively; duration, defined as the time between onset and offset of EMG burst; and area integral value under the waveform.

RESULTS

Effects of thickening demonstrated the extended onset latency, EMG burst duration including falling time and the larger area of EMG in thickened liquid compared to thin liquid, but there was not much difference between thin and thickened carbonated liquids. Carbonation significantly decreased the duration including falling time for thickened but not for thin liquids.

CONCLUSION

Patients with dysphagia can benefit from use of carbonated or thickened water while the effects on swallowing physiology may differ between carbonation and thickening.

The impact of physical therapy on dysphagia in neurological diseases: a review

A neurogenic dysphagia is dysphagia caused by problems with the central and peripheral nervous systems, is particularly prevalent in conditions such as Parkinson's disease and stroke. It significantly impacts the quality of life for affected individuals and causes additional burdens, such as malnutrition, aspiration pneumonia, asphyxia, or even death from choking due to improper eating. Physical therapy offers a non-invasive treatment with high efficacy and low cost. Evidence supporting the use of physical therapy in dysphagia treatment is increasing, including techniques such as neuromuscular electrical stimulation, sensory stimulation, transcranial direct current stimulation, and repetitive transcranial magnetic stimulation. While initial studies have shown promising results, the effectiveness of specific treatment regimens still requires further validation. At present, there is a lack of scientific evidence to guide patient selection, develop appropriate treatment regimens, and accurately evaluate treatment outcomes. Therefore, the primary objectives of this review are to review the results of existing research, summarize the application of physical therapy in dysphagia management, we also discussed the mechanisms and treatments of physical therapy for neurogenic dysphagia.

Effects of carbonated beverages on sustained swallowing behavior changes in older inpatients

Sensory stimulation, including stimulation with carbonated liquids, has been known to influence swallowing activity. The aim of this study is to determine the effect of sustained changes in the swallowing behavior of hospitalized patients without dysphagia using the cervical auscultatory recordings of swallowing sounds. The study participants were hospitalized older adults without dysphagia. The participants were asked to initially swallow water and then a carbonated beverage. The sustained effects of the carbonated beverage in relation to swallowing movements were evaluated by measuring the swallowing sounds at the following time periods: (1) immediately and (2) at 1 to 9 minutes with intervals of 2 minutes after swallowing the carbonated beverage. The swallowing sounds before and after swallowing the same volume of water were also measured and compared on a different day. Analysis was performed to calculate the time from a sound signal to the beginning of the swallowing sound. Significant shortening of the swallowing sound time of the late pharyngeal phase was observed up to 7 minutes after swallowing the carbonated beverage, except during the 3 minutes after swallowing. Shortening of the whole swallowing sound time was observed only immediately after swallowing the carbonated beverage. Regarding the shortening of the acoustic signal in the late pharyngeal period, the effect of cerebral excitability changes due to carbonic acid stimulation was considered.

Are Bubbles the Future of Dysphagia Rehabilitation: A Systematic Review Analysing Evidence on the Use of Carbonated Liquids in Dysphagia Rehabilitation

BACKGROUND

Dysphagia poses a huge health issue in our ageing population, impacting patients psychologically and through risk of aspiration, malnutrition and airway obstruction. The use of carbonated liquids to provide sensory enhancement as a tool to stimulate neuromuscular activity in dysphagia rehabilitation remains an area with limited research. This article reviews current evidence.

METHOD

A data search of PubMed, CINAHL, EMBASE and Cochrane was undertaken with set search terms. Abstracts were reviewed and selected by two clinicians according to inclusion criteria and papers were assessed using PRISMA methodology.

RESULTS

Selected publications (1992-2022) involved a median of 23 participants with predominantly neurogenic dysphagia. Despite the differences in study designs all used videofluroscopy (VF) to assess outcome measures except Morishita et al. who used fiberoptic endoscopic evaluation of swallow (FEES). The studies were small scale but showed encouraging results. However, there was heterogeneity between results of specific outcome measures. One study surveyed taste which was overall positively received.

CONCLUSIONS

There continues to remain limited evidence to direct the use of carbonated liquids in rehabilitation of dysphagia, however its role shows some promise. The heterogeneity of not just study designs but also study participants seems to be a primary barrier. Whilst evidence is encouraging, further prospective studies standardising patient cohorts, methodologies and quantitative outcome measures must be carried out. Longitudinal studies to look at the role of carbonated liquids in secretion management is another area of potential interest. In conclusion the use of carbonated liquid in dysphagia rehabilitation may have a potential role but without firm evidence-based research, successful use in clinical practice cannot be implemented.

Effects of thickened carbonated cola in older patients with dysphagia

Carbonated beverages initiate the swallowing reflex earlier than water and have a shorter pharyngeal transit time. However, the effects of carbonation in thickened beverages of the same flavor on swallowing dynamics have not been reported. Therefore, we investigated the effects of thickened carbonated beverages on swallowing in patients with dysphagia by comparing the swallowing dynamics between thickened carbonated and thickened non-carbonated beverages. We enrolled 38 patients with dysphagia and divided them into two groups. Thickened carbonated and thickened non-carbonated beverages were used. Videoendoscopic swallowing evaluations were performed. Aspiration, penetration, pharyngeal residue, and initiation position of the swallowing reflex were evaluated. The reduction in the amount of residue in both the vallecula (p = 0.007) and pyriform sinus (p = 0.004) was greater after ingestion of thickened carbonated cola than thickened non-carbonated cola. The onset of the swallowing reflex was significantly earlier after ingestion of thickened carbonated cola than thickened non-carbonated cola (p = 0.007). There were no significant differences in the extent of penetration. Thickened carbonated beverages positively affected swallowing compared with thickened non-carbonated beverages. Thus, the use of thickened carbonated beverages may be helpful for patients with dysphagia.

Effects of Carbonated Thickened Drinks on Pharyngeal Swallowing with a Flexible Endoscopic Evaluation of Swallowing in Older Patients with Oropharyngeal Dysphagia

This study aimed to determine the efficacy of carbonated and sweetened drinks added to thickened liquids, which are routinely used for patients with dysphagia to improve dysphagia. Patients swallowed thin liquid (Thin), thickened liquid (Thick), carbonated thin drink (C-Thin), and carbonated thickened drink (C-Thick) in random order. Penetration and/or aspiration were scored using the Penetration−Aspiration Scale (PAS). The residue was scored using the Yale Pharyngeal Residue Severity Rating Scale (YPR-SRS). Swallowing reflex initiation was scored using the Hyodo score. The subjective difficulty of swallowing was scored on a face scale. We analyzed 13 patients with a mean age of 79.6 ± 9.6 years. PAS was significantly lower in the C-Thick group than the Thin group (p < 0.05). Swallowing reflex initiation was significantly different between the Thin and Thick (p < 0.01) groups; moreover, post hoc analysis revealed that it was significantly lower in the C-Thick group than the Thin group (p < 0.01). The subjective difficulty of swallowing in the C-Thick was significantly lower than the Thick group (p < 0.05). C-Thick was easier to swallow than Thick and may improve penetration and/or aspiration in older patients with dysphagia with complex diseases.