Randomised controlled trial of rhinothermy for treatment of the common cold: a feasibility study

van de Hei, Susanne; McKinstry, Steven; Bardsley, George; Weatherall, Mark; Beasley, Richard; Fingleton, James

Control medication, Vitamin C 250mg (Healtheries, Vitaco Health NZ Ltd, Auckland, New 172 Zealand) daily for five days. The randomisation schedule was computer generated by the study 173 statistician, who was not involved in study recruitment, procedures, or data collection. After training on myAIRVO 2 set-up and use, participants were given a modified myAIRVO 2 203 device to use at home according to the same regimen (100% humidity, 41 O C, 35L/min, 120 204 minutes) for up to five days depending on resolution of symptoms. Participants were 205 encouraged to use the device for at least two hours per day and longer if desired in either a 206 single or repeated administration, preferably in the evening. Participants were allowed to reduce 207 the flow to 30L/min or 25L/min according to comfort when at home. After three days participants 208 that were randomised to the myAIRVO 2 group were contacted by phone, to check if they had 209 any adverse events and/or had any problems with using the myAIRVO 2. 210 211 Participants allocated to the control group received their first 250mg Vitamin C tablet in the CTU 212 after randomisation, and then at home for a further four days. Low-dose Vitamin C was used as 213 a control. As therapeutic use of Vitamin C after symptoms develop has not been shown to 214 consistently reduce the duration of colds or improve cold symptoms,[14] participants were not 215 expected to derive benefit above that obtained by the placebo effect. The low dose of vitamin C 216 used in this study is freely available in pharmacies in New Zealand but is unlikely to be of 217 benefit when taken after symptoms develop, as opposed to regular supplementation. 218