Development of a new OSA Guideline at East Suffolk and North Essex NHS Trust (ESNEFT)

The development of a new guideline for perioperative management of obstructive sleep apnoea (OSA) in adults within our Trust had multiple drivers. The Centre for Perioperative Care (CPOC) guidelines, published in 2023, provided a robust framework for risk assessment and perioperative management of patients with known or suspected OSA.[1] Within our Trust there the opportunity to develop an updated, integrated and streamlined guideline, following the merger of Colchester and Ipswich Hospitals to form ESNEFT in 2018, and in the establishment of the Elective Orthopaedic Centre (EOC) at Colchester Hospital, due to open later in 2024. Patients coming to the EOC will be pre-assessed in their base hospitals, and so the development of a unified OSA guideline across sites would be key to ensure consistent pre-assessment and perioperative management. Furthermore, the opening of a new Post-Operative Care Unit (POCU) at Colchester provided the means for enhanced postoperative monitoring for elective surgical patients judged to be at high risk, including those with known or suspected OSA. 

We took the approach of adapting the CPOC guideline to our local circumstances. The idea was to give more direction to pre-assessment nurses and anaesthetists, based on advice from our sleep medicine colleagues, about who should be referred for sleep studies. The process was educational both in terms of the broader context – for example, looking at international guidelines to see how OSA is managed in other health systems – and in the workings of the sleep medicine physicians. It became clear that capacity for sleep studies and CPAP initiation within our Trust was limited both by personnel and space constraints, and that a pragmatic approach would be key to strike a balance between ensuring adequate investigations and / or treatment of OSA when necessary and indicated, versus delaying potentially time-sensitive operations. CPAP would usually be commenced if patients had significant, symptomatic daytime fatigue; therefore this could be assessed at pre-assessment by an Epworth score, the cut-off for significance of 10 or above being determined and already used by the sleep medicine physicians.

Through this process we arrived at a risk assessment and management framework for OSA in adults in the perioperative period informed by guidelines, evidence, and local expertise. There were other aspects of OSA management which were discussed throughout the working process, such as the role of venous bicarbonate measurement, overnight oximetry, and the management of patients undergoing bariatric surgery given the development of a new bariatric service at Colchester. It was felt that both venous bicarbonate and overnight oximetry were not specific for OSA, and would not provide enough benefit to be used routinely, although there may be a role for these tests on a case- by-case basis as decided by the assessing anaesthetist.

The guideline is currently going through the appropriate channels for approval including presentation at clinical governance meetings and education sessions and resources for pre-assessment staff. Presenting our draft guideline at the CPOC leads meeting, organised by the RCoA in May 2024, was a great opportunity to discuss our working process and present our guideline to a network of experts, and hear about all of the excellent work that is going on around the country regarding different aspects of perioperative medicine.

[1] Perioperative Management of Obstructive Sleep Apnoea in Adults. Centre for Perioperative Care. https://cpoc.org.uk/guidelines-resources-guidelines/perioperative-management-osa-adults

Dr Ben Chisnall is an ST6 trainee in anaesthesia in the East of England. He has interests in cardiothoracic anaesthesia, regional anaesthesia, perioperative medicine and medical education