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 and 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.