None listed
Conditions
Brief summary
Nasal hyper reactivity is characterised by a reflex mediated increased sensitivity to inhaled unspecific irritants such as cold air, perfumes and smoke. Patients with obstructive sleep apnoea syndrome (OSAS) are treated with a “continuous positive air way pressure” (CPAP) device that relies upon a good nasal patency during sleep. The present study aims at evaluating a new non-invasive device, the Rhinolux, to identify patients with an increased risk of having nasal hyper reactivity during CPAP treatment. The Rhinolux is an oximetry device that measures changes in nasal blood flow by light absorption in haemoglobin. The majority of the patients in this study will not have tested CPAP before eventhough they have been given a description of the treatment procedure. To control for the bias that having prongs in the nose could effect the nasal blood flow, all subjects will initially wear the prongs for 10 minutes before the CPAP pressure is applied. In this sence the study could be considered to be single blind because only the examiner will be fully aware at what time the CPAP pressure is turned on.
Interventions
After an initial measurement with acoustic rhinometry, rhinomanometry and Rhinolux the subjects are treated with CPAP while lying down. First they will have the nasal prongs of the CPAP fitted with no air pressure for 10 minutes, and then a CPAP pressure of 8 cm H2O will be applied for 20 minutes. The Rhinolux will be fitted during the CPAP provocation to assess changes in nasal mucosal blood flow. Finally, acoustic rhinometry, rhinomanometry and Rhinolux are repeated in sitting and reclining po
After an initial measurement with acoustic rhinometry, rhinomanometry and Rhinolux the subjects are treated with CPAP while lying down. First they will have the nasal prongs of the CPAP fitted with no air pressure for 10 minutes, and then a CPAP pressure of 8 cm H2O will be applied for 20 minutes. The Rhinolux will be fitted during the CPAP provocation to assess changes in nasal mucosal blood flow. Finally, acoustic rhinometry, rhinomanometry and Rhinolux are repeated in sitting and reclining position. Subjective symptoms of nasal congestion will be registered by the subjects on a visual analogue scale sitting and lying down, before and after the CPAP intervention (4 times).
Sponsors
The Woolcock Institute of Medical Research
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Treatment
Masking
Blinded (masking used)
Eligibility
Sex/Gender
All
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
Obstructive sleep apnoea syndrome (OSAS) who attend the sleep investigation unit for CPAP titration and who have not been treated with CPAP during the last year.Non-smoking healthy control subjects without any history of nasal disease, previous nasal surgery or current medication. Negative skin prick test.
Exclusion criteria
Current treatment with nasal steroids or decongestantsNasal polyposisPrevious nasal surgery (septoplasty, turbinectomy, endoscopic sinus surgey)Previous nasal trauma (nasal bone fracture )Previous nasal CPAP treatment less than 1 year ago.Positive skin prick test in controls.
Outcome results
None listed