Non-diluted seawater enhances nasal ciliary beat frequency and wound repair speed compared to diluted seawater and normal saline

Abstract

BackgroundThe regulation of mucociliary clearance is a key part of the defense mechanisms developed by the airway epithelium. If a high aggregate quality of evidence shows the clinical effectiveness of nasal irrigation, there is a lack of studies showing the intrinsic role of the different irrigation solutions allowing such results. This study investigated the impact of solutions with different pH and ionic compositions, eg, normal saline, non‐diluted seawater and diluted seawater, on nasal mucosa functional parameters.MethodsFor this randomized, controlled, blinded, in vitro study, we used airway epithelial cells obtained from 13 nasal polyps explants to measure ciliary beat frequency (CBF) and epithelial wound repair speed (WRS) in response to 3 isotonic nasal irrigation solutions: (1) normal saline 0.9%; (2) non‐diluted seawater (Physiomer®); and (3) 30% diluted seawater (Stérimar). The results were compared to control (cell culture medium).ResultsNon‐diluted seawater enhanced the CBF and the WRS when compared to diluted seawater and to normal saline. When compared to the control, it significantly enhanced CBF and slightly, though nonsignificantly, improved the WRS. Interestingly, normal saline markedly reduced the number of epithelial cells and ciliated cells when compared to the control condition.ConclusionOur results suggest that the physicochemical features of the nasal wash solution is important because it determines the optimal conditions to enhance CBF and epithelial WRS thus preserving the respiratory mucosa in pathological conditions. Non‐diluted seawater obtains the best results on CBF and WRS vs normal saline showing a deleterious effect on epithelial cell function.

Nasal saline irrigation: a clinical update

“…In 2016, an in‐vitro study by Bonnomet et al showed nondilute IS seawater solution more effectively improved ciliary beat frequency and wound repair speed when compared with dilute IS seawater and regular IS (Table ) . In addition, regular IS had a negative effect on epithelial cell function . A 2015 study by Woods et al compared the effect of low‐salt solution, IS, and HS on the antimicrobial activity of nasal secretions (Table ) .…”

Clinical Efficacy of a New Filmogen Polymeric Glycerol Solution for the Treatment of Rhinosinusitis

“…Saline solution used as nasal wash with large volume-low pressure delivery devices or as multiple irrigations is still considered one of the best and safest treatments to ease CRS symptoms as these treatments are safe and have a positive benefit/risk ratio [25,26]. The mode of action, beyond the flushing mechanical action of saline solutions is not clearly established but regular nasal washes may help clean nasal passage, improve respiration, ciliary beats or reduce microbial load thereby alleviating CRS symptoms [27].…”

“…The salt concentration cannot be increased above 3.4%, as the solution then becomes too irritable to the nasal mucosa and may cause severe inflammation and nasal mucosa damage. A few solutions containing higher salt concentrations such as pure or diluted sea water exist on the market as symptomatic treatments only [27].…”

“…A few patients of this study complained about moderate nasal irritation right after each TP application, lasting for about [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] seconds. This may be attributable to the fact that FPG solution is osmotic and draws intracellular hypotonic liquid as soon as it is sprayed as a film over the nasal mucosa.…”

New methods of prevention and treatment of acute respiratory viral infections in children. Local protection factors of the respiratory mucosa

“…В рандомизированном слепом исследовании in vitro сравнили влияние изотонического (0,9%) раствора хлорида натрия, 30% раствора морской воды и натуральной неразбавленной морской воды на частоту биения ресничек респираторного эпителия. Растворы морской воды, особенно неразбавленной, существенно увеличивали частоту биения ресничек по сравнению с изотоническим (0,9%) раствором хлорида натрия, а также ускоряли заживление поврежденного эпителия [41].…”