Mastering Vacuum Swallowing to Improve Pharyngeal Bolus Passage by Creating Negative Pressure in the Esophagus: A Case Report of Two Patients

Abstract

Background: Vacuum swallowing improves pharyngeal bolus passage by creating negative pressure in the esophagus. In this study, we aimed to (1) assess whether patients with dysphagia and lateral medullary syndrome (LMS) could reproduce vacuum swallowing and (2) evaluate its safety using a swallowing and breathing monitoring system (SBMS).

Cases: Two patients with dysphagia and LMS were instructed to perform vacuum swallowing. Videofluoroscopic examination of swallowing (VF) was performed. High-resolution manometry parameters, including the esophageal minimum pressure (Pmin) and maximum pressure (Pmax) in the lower esophageal sphincter, were compared to the values obtained during non-vacuum swallowing. The coordination between vacuum swallowing and breathing was evaluated using an SBMS. VF showed that pharyngeal residues in the pyriform sinus were sucked into the esophagus during vacuum swallowing. No aspiration was observed. During vacuum swallowing, Pmin was significantly lower, and Pmax was significantly higher than the respective measurements during non-vacuum swallowing. In the SBMS study, vacuum swallowing followed an expiratory swallowing pattern; this pattern was observed in three out of five swallowing episodes in Patient 1 and in all swallowing episodes in Patient 2. Deglutition apnea was observed during vacuum swallowing.

Discussion: Vacuum swallowing may be a feasible method for improving pharyngeal bolus passage. Patients could safely master vacuum swallowing. Instructions to exhale before and after vacuum swallowing are recommended to prevent aspiration.