Bonnie Martin-Harris, Kate Davidson, David McFarland
Collectively, these findings support respiratory-swallow coordination as a modifiable target for dysphagia rehabilitation that results in important physiologic and airway protection advantages. RST represents a mechanism-driven approach that extends beyond compensatory strategies and shows promise for scalable, technology-enabled delivery in both clinical and ambulatory settings. This work has implications for swallowing assessment, intervention, and future research across clinical populations.
PURPOSE: This review article provides a programmatic translational synthesis of a research program investigating respiratory-swallow coordination as a modifiable physiologic target underlying swallowing impairment and safety, with a focus on individuals treated for head and neck cancer (HNC). The purpose is to synthesize physiologic evidence, clinical trial outcomes, and translational advances supporting respiratory-swallow training (RST) as a mechanism-based intervention.
METHOD: Evidence is drawn from a series of experimental, observational, and interventional studies conducted over more than 3 decades. Methods include synchronized videofluoroscopy and respiratory measurement to characterize respiratory-swallow coordination, clinical trials evaluating RST across chronic and earlier recovery-stage HNC populations, and ongoing work incorporating wearable sensor technology and synchronous telehealth delivery to support ambulatory monitoring and home-based training. Data from Phase I, Phase II, and ongoing randomized efficacy trials are summarized to illustrate mechanistic and clinical effects of RST.
RESULTS: Across studies, swallowing was most safely and efficiently initiated during mid- to low-quiet (tidal) breathing expiratory lung volumes, whereas deviations from this pattern were associated with increased airway invasion and physiologic impairment. RST reliably increased expiratory-phase swallow initiation and was associated with improvements in swallowing impairment, airway protection, bolus clearance, functional oral intake, and patient-reported outcomes. Phases I and IIa trial data demonstrated significant reductions in physiologic impairment scores and penetration-aspiration severity following training.
CONCLUSIONS: Collectively, these findings support respiratory-swallow coordination as a modifiable target for dysphagia rehabilitation that results in important physiologic and airway protection advantages. RST represents a mechanism-driven approach that extends beyond compensatory strategies and shows promise for scalable, technology-enabled delivery in both clinical and ambulatory settings. This work has implications for swallowing assessment, intervention, and future research across clinical populations.