Coordination between respiration and swallowing during non‐invasive positive pressure ventilation

Abstract

Background and objective: The purpose of this study was to test the hypothesis that the risk of silent aspiration is increased in non-invasive positive pressure ventilation. Methods: We analysed the coordination between respiration and swallowing, in 12 young volunteers and 10 elder volunteers, by simultaneously monitoring respiratory flow, laryngeal movement and swallowing sound in three different conditions: control, continuous positive airway pressure (CPAP), and bi-level positive airway pressure (BiPAP). A step-wise multiple regression analysis was performed with the occurrence rate of inspiration after swallows as the dependent variable and various correlated variables as the independent variables. Results: In both subject groups, the occurrence rate of inspiration after swallow was greater with BiPAP compared with control and CPAP conditions. Repetitive saliva swallowing test count and swallow non-inspiratory flow occurrence rate were extracted as predictor variables for risk of inspiration after swallows during BiPAP treatment. Conclusion: We found that the occurrence rate of inspiration after swallow is increased with BiPAP use irrespective of age. The results suggest that swallow non-inspiratory flow may trigger inspiratory support in the BiPAP mode, resulting in a risk of aspiration.

Inappropriate Timing of Swallow in the Respiratory Cycle Causes Breathing–Swallowing Discoordination

“…Subjects who receive nutrition via non-oral pathways are categorized as Levels 1–3, subjects who receive nutrition by both oral dysphagia diet and alternative nutrition are categorized as Levels 4–6, subjects who receive nutrition by various degrees of dysphagia diet are categorized as Levels 7–9, and normative subjects are categorized as Level 10. Repetitive Saliva-Swallowing Test (RSST) (Hori et al, 2016 ), a count of swallows over a 30-s period, <3. In this test, subjects are instructed to swallow saliva as many times as possible within 30 s. An RSST count of less than three times in 30 s suggests suspected dysphagia, and the sensitivity and specificity of RSST to predict aspiration in videofluorographic examination are reported to be 0.98 and 0.66, respectively (Oguchi et al, 2000 ).…”

Clinical Decision Making in the ICU: Dysphagia Screening, Assessment, and Treatment

“…[73][74][75][76] Some studies suggest the possibility of oral feeding with HFNC, [77][78][79][80][81] and with CPAP, 82,83 while others raise concerns for increased aspiration with nasal CPAP, 84,85 and BiPAP. 86 Without definitive guidance from large studies, the ICU clinician must consider each patient's individual presentation and risk factors, not solely the oxygen delivery mode/level in isolation of these other factors. Moreover, until more definitive studies are completed, relying on instrumental evaluations is necessary under these circumstances.…”

Recent Advances in Rehabilitation for Aspiration Pneumonia

“…1 It is also important to notify that respiration and swallowing are intimately related to each other. 2 The respiratory and swallowing centers in brainstem are located very close and affects each other. During the respiratory distress, the firing of respiratory center is too busy to be coordinated with the firing of the swallowing center.…”

“…During the respiratory distress, the firing of respiratory center is too busy to be coordinated with the firing of the swallowing center. 2 Therefore, the rehabilitation for aspiration pneumonia should be the combination of pulmonary and dysphagia rehabilitations. The pulmonary rehabilitation for aspiration pneumonia is basically similar to the pulmonary rehabilitation in intensive care unit (ICU) which has been discussed in another manuscript "Recent Advances in Pulmonary Rehabilitation for Patients in the Intensive Care Unit (ICU)" of this special edition.…”