Do Disinfectant Solutions during Gargling Reach the Pharynx?

Area of Science:

• Otolaryngology
• Medical Imaging
• Infectious Disease Control

Background:

• Gargling disinfectant is a common practice for symptom relief during COVID-19.
• Disinfectant gargles are believed to reduce upper respiratory infection symptoms.
• Limited data exists on the precise distribution of gargled fluids in the upper airway.

Purpose of the Study:

• To investigate the regions within the upper airways reached by gargled fluids.
• To evaluate the effectiveness of gargling for disinfecting deeper pharyngeal areas.

Main Methods:

• Utilized high-sensitivity flexible endoscopic evaluation of swallowing (hsFEES®) in ten healthy volunteers.
• Employed fast and real-time magnetic resonance imaging (MRI) in one volunteer to visualize gargling patterns.
• Used colored water to track fluid distribution during the gargling process.

Main Results:

• No fluid accumulation was observed on the posterior pharyngeal wall, epipharynx, or hypopharynx in any participant.
• Endoscopic and MRI findings consistently showed fluid coverage limited to the oral cavity and anterior soft palate.
• The deeper regions of the pharynx were not reached by the gargled liquid.

Conclusions:

• Gargling primarily affects the oral cavity and anterior palate, not the posterior pharyngeal wall or deeper airway structures.
• hsFEES® and fast MRI are effective tools for visualizing gargling dynamics.
• Findings challenge the assumption that gargling disinfects the entire upper airway, including the pharynx and hypopharynx.