Scottish Intercollegiate Guidelines Network

1 Scottish Intercollegiate Guidelines NetworkManagement of Obstructive SleepApnoea/Hypopnoea Syndrome in AdultsA national clinical guideline1 Introduction12 Definitions and clinical background33 Diagnosis64 Treatment of OSAHS125 Surgical interventions186 Effects of treatment on driving and quality of life 217 Information for discussion withpatients and carers248 Development of the guideline269 Implementation and audit29 Annexes30 Abbreviations32 References33 June 200373 This guideline is endorsed by the British Thoracic Society Scottish Intercollegiate Guidelines NetworkISBN 1 899893 33 4 First published 2003 SIGN consents to the photocopying of this guideline for thepurpose of implementation in NHSS cotlandScottish Intercollegiate Guidelines NetworkRoyal College of Physicians9 Queen StreetEdinburgh EH2 TO EVIDENCE STATEMENTS AND GRADES OF RECOMMENDATIONSLEVELS OF EVIDENCE1++High quality meta-analyses, systematic reviews of randomised controlled trials (RCTs)

2 ,or RCTs with a very low risk of bias1+Well conducted meta-analyses, systematic reviews of RCTs, or RCTs with a lowrisk of bias1 -Meta-analyses, systematic reviews of RCTs, or RCTs with a high risk of bias2++High quality systematic reviews of case control or cohort studiesHigh quality case control or cohort studies with a very low risk of confounding or biasand a high probability that the relationship is causal2+Well conducted case control or cohort studies with a low risk of confounding or biasand a moderate probability that the relationship is causal2 -Case control or cohort studies with a high risk of confounding or biasand a significant risk that the relationship is not causal3 Non-analytic studies, case reports, case series4 Expert opinionGRADES OF RECOMMENDATIONNote.

3 The grade of recommendation relates to the strength of the evidence on which therecommendation is based. It does not reflect the clinical importance of the least one meta-analysis, systematic review of RCTs, or RCT rated as 1++and directly applicable to the target population; orA body of evidence consisting principally of studies rated as 1+, directly applicable tothe target population, and demonstrating overall consistency of resultsBA body of evidence including studies rated as 2++, directly applicable to the targetpopulation, and demonstrating overall consistency of results; orExtrapolated evidence from studies rated as 1++ or 1+CA body of evidence including studies rated as 2+, directly applicable to the targetpopulation and demonstrating overall consistency of results; orExtrapolated evidence from studies rated as 2++DEvidence level 3 or 4; orExtrapolated evidence from studies rated as 2+GOOD PRACTICE POINTS Recommended best practice based on the clinical experience of the guidelinedevelopment group111 INTRODUCTION1 NEED FOR THE GUIDELINEO bstructive sleep apnoea/hypopnoea syndrome (OSAHS) can be defined as the coexistence ofexcessive daytime sleepiness with irregular breathing at night.

4 The abbreviations OSAS and OSAare used widely and synonymously with OSAHS, however this guideline will use only the is a significant public health problem and there is a large and increasing demand forsleep service facilities due to the high prevalence and growing public awareness of sleep disorders,including OSAHS. A conservative estimate of the prevalence of OSAHS in middle-aged men (30-65 years) is in the range 4%, with most studies giving a prevalence of 1-2% which is asimilar prevalence to Type 1 diabetes and approximately double that of severe Theprevalence of OSAHS in middle-aged women has been less well studied but is probably abouthalf that in males, at around 1%.

5 2A significant variation exists across the UK, both in the availability of diagnostic tests and theprovision for treatment of sleep-disordered consequences of untreated sleep apnoea on daily function are multiple and include increaseddaytime sleepiness, impairment of cognitive function, mood and personality is also associated with a reduction in quality of life6 and there can be adverse effects onothers including impaired relationships between spouses and of sleepinessand impaired concentration resulting from untreated sleep apnoea are thought to have seriousconsequences during activities where reduced alertness is dangerous, such as driving, leading toan increased risk of road traffic ,9 There is objective evidence for a to 12-foldincrease in accident rates among patients with ,8,10 Sleepiness at the wheel is estimatedto cause about 20% of road accidents on major highways, although it is unclear how many ofthese are due to OSAHS.

6 These accidents usually occur at high speed, without avoidance reactionsand are associated with serious injuries and a high mortality ,11,12 The estimated cost to society of a fatal road traffic accident is approximately 1,250,000, makingit highly desirable to produce a national guideline which may help to reduce the medical, socialand financial costs of excessive OF THE GUIDELINEThis guideline presents evidence based recommendations for the diagnosis and management ofobstructive sleep apnoea/hypopnoea syndrome in males and females over 16 years. It is notintended to exhaustively cover all causes of excessive daytime sleepiness in adults nor does itdeal with central sleep apnoea nor specifically with snoring.

7 The guideline aims to producerecommendations which can be used to aid patients, general practitioners (GPs), secondary carephysicians and surgeons to recognise the symptoms of this common disorder, to prioritise referralrequests, to understand how sufferers may be investigated and which treatment modalities arecurrently OF INTENTThis guideline is not intended to be construed or to serve as a standard of medical care. Standardsof care are determined on the basis of all clinical data available for an individual case and aresubject to change as scientific knowledge and technology advance and patterns of care parameters of practice should be considered Guidelines only.

8 Adherence to them will notensure a successful outcome in every case, nor should they be construed as including all propermethods of care or excluding other acceptable methods of care aimed at the same results. Theultimate judgement regarding a particular clinical procedure or treatment plan must be made bythe doctor, following discussion of the options with the patient, in light of the diagnostic andtreatment choices available. However, it is advised that significant departures from the nationalguideline or any local Guidelines derived from it should be fully documented in the patient scase notes at the time the relevant decision is OF OBSTRUCTIVE SLEEP APNOEA/HYPOPNOEA SYNDROME IN AND UPDATINGThis guideline was issued in 2003 and will be considered for review in 2006, or sooner if newevidence becomes available.

9 Any updates to the guideline will be available on the SIGN DEFINITIONS AND BACKGROUND2 Definitions and clinical FEATUREST here are many causes of excessive sleepiness but the commonest treatable medical cause is theobstructive sleep apnoea/hypopnoea syndrome (OSAHS). This is a clinical condition, withrecognisable symptoms, that occurs because the upper airway collapses intermittently andrepeatedly during sleep. This collapse can be complete, with total obstruction of the airwaylumen and no respiratory airflow (apnoea), or partial, with reduction in the cross-sectional areaof the upper airway lumen causing hypoventilation (hypopnoea). An apnoea is arbitrarily definedin adults as a ten second breathing pause and an hypopnoea as a ten second event where there iscontinued breathing but ventilation is reduced by at least 50% from the previous baseline duringsleep.

10 In some centres, hypopnoeas are defined using additional criteria including associatedoxygen desaturation (dips) or electroencephalogram (EEG) the sufferer falls asleep the muscle tone in the upper pharyngeal airway decreases leading toupper airway narrowing. This, in turn, produces an increase in inspiratory effort in an attempt toovercome this airway narrowing which then leads to a transient arousal from deep sleep towakefulness or a lighter sleep phase which allows restoration of normal airway muscular toneand calibre. The patient then falls more deeply asleep again and the whole cycle repeats can occur many hundreds of times throughout the night leading to fragmentation of normalsleep architecture and a reduction in the quality of sleep with the generation of restless, disturbedand unsatisfying sleep.