Efficacy of buffered hypertonic seawater in different phenotypes of chronic rhinosinusitis with nasal polyps after endoscopic sinus surgery: a randomized double-blind study

Purpose: Nasal douching is commonly used as a postoperative management strategy for chronic rhinosinusitis with nasal polyps (CRSwNP). Few studies to date have compared the effectiveness of nasal douching in CRSwNP phenotypes after endoscopic sinus surgery (ESS). We evaluated the efficacy of seawater types in eosinophilic CRSwNP (ECRSwNP) and noneosinophilic CRSwNP (nonECRSwNP) after ESS.

Methods: Patients with bilateral CRSwNP who had undergone ESS were blindly randomized to receive buffered hypertonic seawater (BHS) (n = 48) or physiological seawater (PS) (n = 45). CRSwNP patients were stratified by phenotypes (ECRSwNP and nonECRSwNP) retrospectively according to whether tissue eosinophils exceeded 10%. Follow-up evaluations were conducted at 2, 8, 16, and 24 weeks after surgery. Evaluations included the 22-item Sino-Nasal Outcome Test (SNOT-22), visual analog scale (VAS), Lund-Kennedy endoscopic score (LKES), saccharine clearance time (SCT), and adverse events.

Results: All of the patients experienced significant improvements in SNOT-22 scores, VAS scores, and LKES over time. BHS resulted in better improvement of LEKS and SCT relative to PS at 8 weeks postoperatively. Mucosal edema formation was significantly reduced with less crusting among HBS recipients at 8 weeks. After stratification, only patients in the nonECRSwNP + BHS subgroup showed a significant improvement in LEKS and SCT at 8 weeks postoperatively. Side effect profiles were not significantly different among the groups.

Conclusions: BHS has a better inhibitory effect on mucosal edema and crusting during the early postoperative care period of CRSwNP. Among all of the patients, nonECRSwNP patients showed a significant improvement in LEKS and SCT at 8 weeks.

Keywords: Buffered hypertonic seawater; Endoscopic sinus surgery; Eosinophilic chronic rhinosinusitis with nasal polyps; Esoinophil; Noneosinophilic chronic rhinosinusitis with nasal polyps; Physiological seawater.