The Respiratory-Swallow Coordination may be Related to Aspiration in Infratentorial Stroke Patients

To investigate the characteristics of respiratory-swallow coordination (RSC) in poststroke dysphagia (PSD) patients following infratentorial stroke (IS) and further explore their association with aspiration. PSD patients after IS and age-matched healthy controls were recruited. Nasal airflow and sound signals were recorded using a nasal cannula-type flow sensor and contact microphone, which were synchronized with videofluoroscopic swallowing studies (VFSS). For healthy controls, only nasal airflow and sound signals recordings were conducted. A 5 ml thickened liquid was utilized during these assessments. The penetration-aspiration scale (PAS) score was determined through VFSS. Various parameters, including swallowing apnoea duration (SAD), swallowing duration (SD), swallowing latency duration (SLD), number of swallows (NS), and RSC patterns, were analysed to assess RSC. A total of 37 patients with PSD following IS-comprising 25 non-aspirators and 12 aspirators-and 31 age-matched healthy controls were included. The PSD patient group exhibited a shorter SAD (p = 0.016), a longer SD (p = 0.000), and fewer NS (p = 0.000) compared to the healthy control group. Among the PSD patients, those who aspirated exhibited a notably shorter SAD (p = 0.018) and longer SD (p = 0.028) compared to non-aspirators. The prevalence of the swallow-inspiration pattern was higher in PSD patients (p = 0.006), particularly among those who aspirated (p = 0.010). Logistic regression analysis and the area under the receiver operating characteristic curve (AUC) indicated that both SAD (AUC = 0.825, p = 0.002) and SD (AUC = 0.757, p = 0.020) were significant predictors of aspiration. The optimal cut-off values for SAD and SD were determined to be 0.19s and 1.93s, respectively. The RSC characteristics in patients with PSD following IS differed from those observed in healthy controls, particularly among patients who experienced aspiration. In these patients, a shorter SAD and longer SD may contribute to an increased risk of aspiration.