Investigating the efficacy and tolerability of CPAP administered through a novel interface

We are conducting a trial of a novel device (S1H oral device) modified for the delivery of continuous positive airway pressure (CPAP) in individuals with obstructive sleep apnea (OSA). The S1H device is typically used to progressively rehabilitate patients with temporomandibular joint (TMJ) and airway disorders. It has appliance features which passively position the patients jaw and muscles into an ideal position to decompress the TMJ and open the airway. The device consists of 4 breathing holes which regulate oral breathing, a tongue elevator and tongue tag which lift the tongue into correct position out of airway, a lip bumper to retrain the atypical swallow, and an edge to edge offset and thick base to open the airway. The device also includes tongue, lip and jaw press tubes which allow the patient to press on and actively exercise tongue lip and jaw muscles respectively. In the current study, the device will be placed in the participants mouth (like a mouthguard) and CPAP will be delivered through the oral port. Briefly participants will undergo two assessments. Part A will involve an in laboratory assessment and if completed successfully, participants will invited into an at home trial. Part A: In-lab assessment In a randomised order, participants will be fitted with either their own CPAP mask (Usual mask interface) or the modified S1H oral device. The mask will be briefly tested under pressure and adjusted to find an optimal comfort/mask seal settings. Once fitted, participants will lie on the bed and wear the interface while CPAP is applied for a minimum of 30 mins. The CPAP machine will be set to start pressure at 4cmH2O and will ramp to the patients current prescribed CPAP level (or 90/95th%tile equivalent setting) over 5 minutes. After ramping, participants will remain lying in bed for a further 20 minutes at their prescribed CPAP level. During this period, participants will be asked to complete subjective assessments of comfort/tolerability (Landry intolerability scale) every 5 minutes. Ventilation and mask leak will also be continuously recorded through this session. At the completion of this session participants will also be asked “Compared to their own mask do you find the tolerability of this interface to be more, less or the same as your current mask.” This laboratory test will provide detailed data regarding the performance and tolerability of the S1H oral device, but will also serve as an important acclimatization period that will allow us to test whether participants will be able to tolerate the mask sufficiently to proceed further to overnight use of the device during sleep. Part B: At-home performance. Subjects will next participate in a randomized non-blinded cross-over trial. Participants will be randomized to use either the (1) Usual mask interface or (2) S1H oral device with CPAP connection first. Patients will be given a CPAP machine (Phillips Dreamstation) and will use this machine with the interface they are randomised to for 2 weeks in the home. Participants will be encouraged to use the interface for the entire sleep period every night (i.e. as long as they can tolerate). At the end of this two weeks, the investigators will download the machines data (either in person or via the cloud). Participants will also be asked to fill out questionnaires that capture symptoms (ESS) and side effects of the interface used (i.e. TMJ issues, discomfort, mouth ulcers, comfort, ease of cleaning, dry mouth etc). Participants will then cross over to the other interface and use that for a period of two weeks. In the second arm, Participants will fill out the same questionnaires. At the conclusion of the study, patients will be asked which interface they prefer and why.