Impact of Nasal Irrigation With Iodized Table Salt Solution on Mucociliary Clearance: Proof-of-Concept Randomized Control Trial

Abstract

Introduction Saline nasal irrigation is a common recommendation shared between the majority of clinical guidelines for sinusitis and rhinitis in adults and children. Studies involving homemade saline have typically involved the use of noniodized salt. However, the literature does not contain any descriptions for the use of iodized table salt in homemade saline solutions. Objectives To study the usefulness of iodized salt in homemade saline and its impact on mucociliary clearance (MCC). Methods Only healthy volunteers were enrolled in this randomized controlled trial. The sinonasal outcome test (SNOT)-22 and rhinoscopy were used to rule out any clinical evidence of sinusitis or rhinitis in the enrolled subjects. The saccharine clearance time (SCT) was used to evaluate MCC at baseline. Each candidate received 2 different nasal wash solutions—one containing iodized salt and the other containing noniodized salt—on different days. Visual analog scale pain scores were recorded while using each type of nasal wash. The SCT was assessed after each wash. Results Thirty-eight healthy candidates (18 men and 20 women) were enrolled in the study. All subjects were in their 30s. The mean baseline SCT was 10.92 minutes. The use of the noniodized salt solution led to a nonsignificant change ( P = .139) in mean SCT (9.68 min). In contrast, a significant change ( P = .035) was observed in mean SCT after the use of the iodized salt solution (9.06 min). However, the mean postirrigation SCT was not significantly different between solutions ( P = .31). No significant differences were observed in pain/discomfort experience between solutions. Conclusion MCC improved with both solutions. Interestingly, the improvement was significant, when the iodized salt nasal irrigation solution was used. This finding contradicts the conventional recommendation against the use of iodized salt in nasal rinse solution. Moreover, this solution was well tolerated. Further studies regarding the long-term safety are recommended.

Essentials in saline pharmacology for nasal or respiratory hygiene in times of COVID-19

“…Pure water severely damages the normal human nasal epithelial cells, while isotonic saline (in contrast to hypo-and hypertonic saline) does not affect their morphology [45,46]. Hypertonic saline has been shown to decrease the ciliary movement in human nasal epithelium [43,47], while others report a faster MCC in healthy subjects, after-single dose nasal irrigation, or in the airways at 30 min, but not 4 h after inhalation (attributed to depletion of airway mucin) [44][45][46][47][48][49][50]. Hypertonic saline induces osmotic pressure, but has also been found to decrease the potential difference in nasal epithelia-a rapid, reversible, and dose-related effect indicating a direct effect of NaCl on ion transport across the human airway epithelium (not just attributable to a simultaneous change in osmolarity) [51].…”

Essentials in saline pharmacology for nasal or respiratory hygiene in times of COVID-19

“…We propose isotonic saline rather than hypertonic saline as it is devoid of the side effects that have been associated with hypertonic saline (changes in cell morphology [51,52], increased nasal epithelial permeability [58,59], nasal burning/irritation [60] and when nebulizing: induction of bronchoconstriction or cough [61][62][63][64]. Until more clinical documentation becomes available, isotonic saline might thus be preferred to hypertonic saline for nasal hydration/hygiene, either as nasal spray or nasal irrigation -to be used from the rst onset of common cold symptoms.…”

“…The osmolality of saline plays an important role. Pure water severely damages the normal human nasal epithelial cells, while isotonic saline (in contrast to hypo-and hypertonic saline) does not affect their morphology [[51], [52]]. Hypertonic saline has been shown to decrease the ciliary movement in human nasal epithelium [49,[53]], while others report faster MCC in healthy subjects, after-single dose nasal irrigation, or in the airways at 30 min, but not 4 h after inhalation (attributed to depletion of airway mucin) [47-,[54], [55], [56]].…”

Essentials in saline pharmacology for nasal or respiratory hygiene in times of COVID-19

“…1) Осмолярність сольового розчину. Чиста вода сильно ушкоджує нормальні клітини назального епітелію людини, тоді як ізотонічний розчин (на відміну від гіпо-та гіпертонічного) не впливає на їхню морфологію [45,46]. Було показано, що гіпертонічний розчин зменшує рух війок назального епітелію людини [43,47], у той час як інші автори повідомляють про швидке MCC у здорових суб'єктів після одноразового промивання носа або в дихальних шляхах через 30 хв., але не через 4 години після вдихання (що приписується виснаженню муцину дихальних шляхів) [44][45][46][47][48][49][50].…”

“…Чиста вода сильно ушкоджує нормальні клітини назального епітелію людини, тоді як ізотонічний розчин (на відміну від гіпо-та гіпертонічного) не впливає на їхню морфологію [45,46]. Було показано, що гіпертонічний розчин зменшує рух війок назального епітелію людини [43,47], у той час як інші автори повідомляють про швидке MCC у здорових суб'єктів після одноразового промивання носа або в дихальних шляхах через 30 хв., але не через 4 години після вдихання (що приписується виснаженню муцину дихальних шляхів) [44][45][46][47][48][49][50]. Гіпертонічний сольовий розчин індукує осмотичний тиск, але також було виявлено, що він зменшує різницю потенціалів у назальному епітеліїшвидкий, оборотний та дозозалежний ефект, що вказує на прямий вплив NaCl на транспорт іонів через епітелій дихальних шляхів людини (а не тільки пов'язаний із одночасною зміною осмолярності) [51].…”