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Background: Sickle cell anaemia (SCA) is an inherited disorder of haemoglobin. Patients experience long-term health care problems, affecting quality of life (QOL) including frequent acute pain, which is difficult to document in trials except as hospital admissions. Pilot data suggests that overnight respiratory support, either supplementary oxygen or auto-adjusting continuous positive airways pressure (APAP), is safe and may have clinical benefit. This pilot trial aims to determine which intervention is more acceptable to participants and whether there are other advantages of one over the other, e.g. in respiratory function or haematological parameters, before conducting the Phase 2 trial of overnight respiratory support funded by the National Institutes of Health Research., Methods/design: This is a pilot cross-over interventional trial with the order of interventions decided by simple randomization. Ten adults (age over 18 years) and 10 children (aged between 8 and 18 years) with homozygous sickle cell disease (haemoglobin SS, HbSS), recruited regardless of symptoms of sleep-disordered breathing, will undergo overnight pulse oximetry and will have two interventions, overnight oxygen and APAP, for a week each in randomised order with a washout week between interventions. Participants will complete online diaries via an iPad throughout the 29 days of the study and will complete QOL questionnaires and have measurement of haematology, biochemistry, spirometry and lung volumes (adults only) at 3 time points, at baseline and after each intervention, as well as in-depth semi-structured qualitative interviews after each intervention, carried out by an experienced psychologist. Both qualitative and statistical methods will be used to analyze the data. The primary outcome is qualitative data looking at participant experience from the transcribed interviews after each intervention. The participant's view on feasibility, acceptability and preference will specifically be explored. The QOL, laboratory and lung function data will be compared with baseline for each arm., Discussion: Patient and public involvement is an integral part of this trial and the key outcome is the qualitative result, which is dependent on obtaining good quality data to advise on participant feasibility, acceptability and preference. This is being addressed by using a standard interview. The development of a pain endpoint is another important outcome and collecting daily measurements is likely to be challenging. Research results will be used to inform design of the Phase 2 trial., Trial Registration: ISRCTN46078697 18 July 2014.

Following treatment with continuous positive airway pressure (CPAP), some patients with obstructive sleep apnoea (OSA) remain sleepy despite effective CPAP and attention to other diagnoses that can provoke sleepiness. It is unclear if this residual sleepiness is an irreversible result of their previous OSA and merits consideration for pharmacological treatment or simply because of the many and varied causes of sleepiness normally found in the community. We have measured levels of sleepiness, using the Epworth Sleepiness Score (ESS), in 572 patients on CPAP and compared them with a control group of 525 subjects from a community survey, which would have included the usual lifestyle reasons for sleepiness as well as any undiagnosed sleep disorders. There was no difference in the percentage of patients with an ESS >10 in the CPAP group compared with the controls (16.1 versus 14.3, P = 0.54). Thus, although there clearly are sleepy patients within the CPAP group, the prevalence is no higher than in the community. We question whether so-called 'post-CPAP sleepiness' should be regarded as any more abnormal and worthy of treatment than a 'normal' population. Post-CPAP sleepiness as a specific disorder may not exist.

The purpose of this project was to audit clinical practice and to investigate the time taken to wean patients using continuous positive airway pressure (CPAP) as a method of respiratory support prior to the introduction of a weaning protocol. Data was collected over a two-month period and 43 patients were included in the audit. Criteria for inclusion were that each patient had previously received mechanical ventilation and was subsequently weaned with the aid of CPAP or had received CPAP and was weaning from CPAP alone. The average time taken to wean was 95 hours (3.96 days) and ranged from one to 41 days. There was no correlation between the length of weaning time and the patient's APACHE II Score or the length of time spent on invasive ventilation prior to weaning on CPAP. However, there was a consistency in the time spent on CPAP as a percentage of the total weaning time. The audit identified large variations in the process and time taken to wean patients from CPAP. This might suggest that CPAP is used in a routine or arbitrary manner rather than a selective response to patients' specific needs.