Saline nasal irrigation for acute sinusitis (SNIFS II): a randomised controlled pilot trial with nested process evaluation.

BACKGROUND: Despite having marginal beneficial effects, antibiotics are routinely prescribed in adults with acute sinusitis. Alternative interventions for this common condition are urgently needed. AIM: To assess the feasibility and acceptability of saline nasal irrigation for acute sinusitis. DESIGN & SETTING: Randomised controlled pilot trial with nested process evaluation in 24 English general practices between October 2019 and May 2021. METHOD: Participants were randomised to advice to high volume hypertonic saline nasal irrigation with a delayed antibiotic prescription or usual care. Feasibility outcomes included recruitment and follow-up rates, adherence, and acceptability of the intervention. RESULTS: Of those invited, 81/107 (76%) consented and were randomised (42 intervention, 39 usual care). Two participants were excluded due to ineligibility. Antibiotic prescribing strategies were recorded at baseline for 79/79 (100%), with no or delayed antibiotics prescribed in 60% (24/40) of the saline group versus 38% (15/39) of the usual care group. At follow-up, 80% (63/79) of participants recorded whether they consumed antibiotics or not. Among those from the intervention group who returned a symptom diary, 96% (22/23) and 65% (15/23) reported using saline nasal irrigation during the first and second week, respectively. Semi-structured interviews with 16 participants revealed that most were positive about trial participation and viewed saline nasal irrigation as acceptable, noting it as alternative to antibiotics. CONCLUSION: Saline nasal irrigation is deemed acceptable for adults with acute sinusitis and a trial of such intervention is feasible. A large trial is warranted to assess the effectiveness of this intervention for this common condition.