Prolonged Overnight Oximetry in Obstructive Sleep Apnoea

This study is looking at the way in which patients with obstructive sleep apnoea (OSA) are diagnosed. The investigators current practice is to offer patients who are referred to the sleep centre with possible sleep apnoea a single night's oximetry recording. A decision is then made based on this screening test as to whether the patient has OSA, does not have OSA or requires a further investigation. There can be significant variation in the severity of OSA between nights. This study is designed to investigate if recording data from multiple nights will give any better indication on the presence and severity of obstructive sleep apnoea. Patients referred for overnight oximetry recordings that report excessive daytime sleepiness are eligible to enter the trial. On enrolment participants will all undergo a single night recording with the oximetry device currently in use by the recruiting sleep centre. In addition they will be asked to wear the prolonged recording oximeter (PRO) that allows for multiple nights data to be stored, and continue wearing this for a total of four nights. On returning both oximetry devices, this data will then be analysed and if it demonstrates evidence of OSA participants will return to the standard clinical pathway and be offered a trial of treatment with continuous positive airway pressure (CPAP) therapy. If no evidence of OSA is seen participants will also revert back to the standard clinical pathway, which may involve a further inpatient sleep investigation being arranged. The number of patients identified as having OSA based on the single first night recording will be compared to those identified as having OSA only after the additional nights recording. All participants will return to the current standard pathway of care on leaving the trial.