The Effects of Saline Solution Irrigation on Nasal Mucus Secretion: in vivo and in vitro Study

Kim, Jung Soo; Lee, Kyu Yup; Jung, Sang Sik; Kim, Bu Il; Jang, Hee Sang; Song, Sun Hee

Abstract

BACKGROUND AND OBJECTIVES
Various saline solution formulae have been used frequently in patients with rhinosinusitis. However, there are not enough scientific evidences supporting the effect of irrigation of the nose with saline solution. We investigated the effects of saline solution on mucus secretion, vascular response, subjective symptoms and nasal cavity air-space volume changes using in vitro and in vivo test. MATERIALS AND METHOD: In vitro study, inferior turbinate mucosa were harvested from patients who had chronic hypertrophic rhinitis. These were incubated with 0.9%, 3%, 6% of saline solutions, and control solution. Concentrations of mucin and lysozyme were measured from them. In vivo study, the nasal cavity of normal control group and patients with septal deviation were irrigated with 0.9%, 3%, 6% of saline solutions. Lavage fluids were collected from the ipsilateral and contralateral sides to measure the concentrations of varies constituents such as mucin, lysozyme, total protein, and albumin. Patients recorded subjective symptoms and nasal cavity air-space volume was assessed by acoustic rhinometry after each irrigations. RESULTS: In vitro study, the concentrations of mucin and lysozyme were increased in the dose-dependent manner by increasing the osmolarity. In vivo study, the sensation of rhinorrhea, pain and nasal blockage were increased as the concentration of saline increased. Furthermore, the concentrations of mucus and total protein also increased by increasing concentration of saline solution at ipsilateral side. However, contralateral reflex-mediated effect were negligible. There was no change in air-space volume. CONCLUSION: The saline solution induced secretion of mucus mignt be through axon reflex mediated neuronal effect. The increased mucus may change the rheology of mucus which, in turn, could increase mucociliary action in the nasal cavity.