Protocol for a randomised, single-blind, two-arm, parallel-group controlled trial of the efficacy of rhinothermy delivered by nasal high flow therapy in the treatment of the common cold

Bird, Grace; Braithwaite, Irene; Harper, James; McKinstry, Steven; Koorevaar, Iris; Fingleton, James; Semprini, Alex; Dilcher, Meik; Jennings, Lance; Weatherall, Mark; Beasley, Richard

The common cold is the most common infectious disease affecting humans. It is usually a selflimiting disease, however the common cold can cause significant morbidity and has a substantial economic impact on society. Human rhinoviruses (HRV), which cause up to two thirds of colds, have temperature-dependent replication and most HRV strains replicate optimally at 33°C. Delivery of heated, humidified air to the upper airways has the potential to reduce viral replication, but evidence of the effectiveness of this treatment of the common cold is inconclusive. We plan to test the hypothesis that delivery of humidified air heated to 41°C at high flow, nasal high flow rhinothermy (rNHF), for two hours daily for five days, is more effective in reducing common cold symptom severity and duration, than five days of 'sham' rhinothermy.