Review of prophylactic swallowing interventions for head and neck cancer

Head and neck cancer treatment destroys nerves and/or organs associated with swallowing. Previous studies have investigated the efficacy of exercises for muscles used in swallowing before treatment in reducing disuse atrophy and delaying the occurrence of muscle fibrosis. However, the rehabilitation effects of training and the optimal intervention strategy are unknown.To establish evidence for the efficacy of prophylactic swallowing interventions in reducing aspiration and restoring oral intake in patients with head and neck cancer with dysphagia.We searched electronic databases (PubMed, Embase, Cochrane and MEDLINE) for studies published up to June 2021 reporting outcomes following prophylactic swallowing interventions in patients with head and neck cancer with dysphagia and the related influencing factors. The methodological quality of the literature was assessed using the Joanna Briggs Institute appraisal tools.The search identified 1468 articles, and 13 studies were eventually included. Four categories involving 12 different swallowing interventions were classified. Regarding the descriptive analysis of the rehabilitation effects across all studies, in terms of oropharyngeal safety, five studies showed that swallowing interventions reduced the risk of aspiration, penetration or residue. In terms of oral intake and tube feeding dependence, four studies demonstrated reduced time to return to oral intake in the intervention group compared with the control group. In terms of intervention adherence, three studies showed that speech-language pathologist- and nurse-supervised training was a potential promoter of adherence, and five studies showed that the negative factors affecting adherence included pain, fatigue, forgetting, smoking, decreased exercise motivation, side effects of radiotherapy and distance to the rehabilitation site.Preventive swallowing interventions may be effective at reducing aspiration, improving swallowing function, and restoring oral intake. However, due to the lack of standardization and consistency of interventions and measurement results, which prevented the production of a best practice guide, future rigorous methodological trials will be needed to determine the most effective interventions for maximizing exercise adherence over the long term.