The aim of this study is to investigate the effects of morphine (a drug commonly used for the
treatment of moderate to severe pain, particularly following surgery) on the number of pauses
in breathing in patients with moderate obstructive sleep apnoea (OSA). Morphine has been
shown to reduce upper airway muscle tone and can also cause shallow breathing, which can
affect breathing function in patients with sleep apnoea. However, to date these effects have
not been proven in clinical trials. Although, caution is advised when prescribing morphine to
patients with sleep apnoea, there is currently no strong evidence that morphine makes sleep
apnoea worse. Only one randomised controlled trial (considered the gold standard in medical
research) has shown no worsening of symptoms for patients with sleep apnoea. The effect of
morphine on patients with sleep apnoea will be assessed in a safe, controlled, hospital
environment. Information from the study will help inform doctors about the safety of giving
morphine to patients with sleep apnoea in urgent situations, for example after surgery.
The results of this study will enable clinicians to make better decisions when prescribing
this drug to patients with OSA in the future.