Mapping of the Execution of Resonance Tubes Phonation Immersed in Water Exercise in Adults: A Scoping Review

To map the execution of resonance tubes phonation immersed in water exercise in adults with healthy or altered voices. This study was a scoping review. An electronic search was performed using the following databases: MEDLINE, LILACS, SCOPUS, Web of Science, EMBASE, Cochrane Library, gray literature, and a manual search. A blinded review was performed by two authors to determine the selection and extraction procedures. Studies with adult participants with dysphonic or healthy voices who underwent intervention with phonation in a resonance tube immersed in water in the context of the vocal clinic, with an experimental intervention, quasi-experimental, or before and after the intervention were included. Data from the publication, sample, execution, and results obtained from the exercises were extracted by two blinded reviewers. Disagreements were resolved through consensus. The analysis was performed quantitatively. A total of 44 publications were analyzed. Among these, Brazilian studies were the most frequent, with a publication peak in 2020. The characterization of the sample was variable, with a higher frequency of participants of both sexes who were not voice professionals. The most frequent studies were before and after exercise with a resonance tube immersed in water, in one session, with an exercise execution time of 3 minutes; in cases of more than one series of executions, the 30-sseconds rest time was more frequent. The most used resonance tube was a flexible silicone tube, with a wall thickness of 0.1 mm, immersion container in a 500-, 510-, or 600-mL bottle, 2/3 filled with water, and the resonance tube immersed 2 cm from the water surface. The most used phonatory task was flow phonation with rounded lips similar to the articulation of the vowel /u/. Acoustic analysis and vocal self-assessment are the most commonly used outcome measures. The best results were obtained in the self-assessment. There is significant variability in the information on the execution of resonance tubes phonation immersed in water exercise influenced by vocal diagnosis and experience with previous vocal training. Studies on the effects of this exercise have been concentrated over the last decade and are of the vocal training and therapy. Acoustic and self-assessment measures were used to verify the results, with self-assessment being the outcome that most frequently indicated positive results.