Obstructive Sleep Apnoea (OSA)

Overview

***Update 14.6.24*** The sleep service is open for both urgent and routine referrals. However, please note that urgent referrals will be prioritised (see Red Flag section below). The BNSSG ICB and Sleep Service at UHBW have developed a set of referral criteria (as outlined below) and a referral proforma  (also available as an EMIS template).

Overview

Obstructive sleep apnoea (OSA) is a common condition involving repetitive collapse of the upper airway during sleep. Prolonged hypoxia results in an arousal from sleep, restoration of upper airway muscle tone and re-opening of the airway. Multiple arousals throughout the night result in poor sleep quality.

OSA is associated with significantly increased risk of high blood pressure, stroke, heart attack and diabetes, as well as mental health conditions including depression and anxiety.

The OSA service provides assessment for patients with suspected OSA and other sleep disorders, which are predominantly respiratory based, although they do see some of the other 84 recognised sleep disorders.

Clinical Knowledge Summaries has advice on assessment and management of obstructive sleep apnoea and includes advice on management in primary care.

The OSA service offers:

• Assessments which may include overnight oximetry in the home or polysomnography within the sleep unit.
• Treatment pathways which may include lifestyle changes (advice given), continuous positive airway pressure (CPAP), or alternatives where appropriate.
• CPAP services - provided to patients within Bristol, Weston, Bath and the surrounding area.
• Ongoing management of CPAP patients - provided by a multidisciplinary team of physiologists and a clinical scientist and respiratory physicians.

What to do before referral

Assessment in primary care

Take a sleep history and assess people for OSAHS if they have 2 or more of the following features (1):

• snoring • witnessed apnoeas • unrefreshing sleep • waking headaches • unexplained excessive sleepiness, tiredness or fatigue • nocturia (waking from sleep to urinate) • choking during sleep • sleep fragmentation or insomnia • cognitive dysfunction or memory impairment.

The Epworth Sleep Score is advised as part of the assessment - a score of greater than 10 indicates abnormal daytime sleepiness but is not diagnostic for OSA. Do not use the Epworth Sleepiness Scale alone to determine if referral is needed, because not all people with OSA have excessive sleepiness.

The STOP-BANG score (MDcalc) is also a useful indicator of OSA risk and is becoming more widely used.

All patients should be given advice and support on conservative treatment in primary care. Patients at higher risk should also be referred without delay (see Red Flag section below). Patients who do not meet criteria for urgent referral should be managed in primary care and referrals will only be accepted where criteria have been met.

Screen for other causes of fatigue

Please ensure that the ICE fatigue symptom profile bloods have been checked within the last 6 months for all patients reporting tiredness for >4 months and manage any underlying conditions before referral:

• Full blood count, Serum Electrolytes, Liver Function Tests, Calcium, TSH, CRP, HbA1c, Creatine Kinase, Coeliac screen.
• Consider Vitamin D measurement if other symptoms and/or treat if in at risk groups - see Vitamin D (Remedy BNSSG ICB).
• Consider checking ferritin if restless leg syndrome – see Restless Leg Syndrome (Remedy BNSSG ICB)

Lifestyle management in primary care

For patients who do not meet criteria for referral without delay, conservative treatments for a minimum of 6 months should be tried before considering referral:

• Weight loss - see Weight management page
• Medication review  - reduction of medication that can exacerbate sleep apnoea. including moving away from strong analgesia, sedatives and meds such as pregabalin and gabapentin where possible.
• Smoking cessation - see Smoking cessation page for services
• Alcohol reduction - see Alcohol misuse page for advice
• Occupation - ensure occupational risks have been addressed.
• Driving advice - all patients should receive advice about driving (see below)

If these steps do not improve symptoms and the patient has significant functional impairment then referral may be appropriate. If a referral is subsequently made then please include details on how the above issues have been addressed.

Driving Advice and Suspected OSA

Patients who have excessive sleepiness due to suspected obstructive sleep apnoea syndrome must not drive.

However, patients should not be advised to inform the DVLA until a diagnosis of OSAHS has been made and advice given to the patient by the Sleep Team. Please refer to https://sleep-apnoea-trust.org/driving-and-sleep-apnoea/detailed-guidance-to-uk-drivers-with-sleep-apnoea/ for further advice.

See Clinical Knowledge Summaries for Advice on Driving

The DVLA advice on Excessive sleepiness - including obstructive sleep apnoea syndrome may also be helpful. There is also link to a patient leaflet 'Tiredness can kill'.

Red Flags

Indications for referral without delay

Patients in the following groups should be referred immediately if they have suspected OSA and referral marked urgent (please use the Referral Proforma - also available as an EMIS template):

• Patients that have a vocational driving job
• Patients that have a job for which vigilance is critical for safety
• Patients that have unstable cardiovascular disease, for example, poorly controlled arrhythmia, nocturnal angina or treatment-resistant hypertension
• Patients that are pregnant
• Patients that are undergoing preoperative assessment for major surgery
• Patients that have non-arteritic anterior ischaemic optic neuropathy

Lifestyle modification while awaiting assessment should still be advised in the above groups but referral should not be delayed.

Referral Criteria

Referral Criteria are also outlined on the Sleep Medicine Referral form (also available as an EMIS template)

Urgent Criteria (At least one of below. Routine criteria must also be met):

• Vocational Driver (Including train drivers and pilots)
• Vigilance-critical occupation (police officer, gas fitter, surgeon, etc…) 
• Unstable cardiovascular disease
• Pregnancy 
• Pre-operative assessment before major surgery 
• Non-arteritic anterior ischaemic optic neuropathy

Routine Criteria (at least 2, including at least 1 major, are required):

Major

• Snoring
• Witnessed Apnoeas
• Choking during sleep
• Unexplained sleepiness, tiredness, or fatigue

Minor

• Unrefreshing sleep
• Waking headaches
• Nocturia
• Sleep fragmentation or insomnia

Please ensure that the ICE fatigue symptom profile bloods have been checked within the last 6 months for all patients reporting tiredness for >4 months and manage any underlying conditions:

• Mandatory: Full blood count, Serum Electrolytes, Liver Function Tests, Calcium, TSH, CRP, HbA1c, Creatine Kinase, Coeliac screen.
• Consider Vitamin D measurement if other symptoms and/or treat if in at risk groups.
• Consider ferritin if restless leg syndrome.

Unless the patient meets criteria for an urgent referral, the BNSSG Integrated Care Board advise the following steps must have been taken, if appropriate, before referral to secondary care:

Weight

If BMI >30, then engagement in weight management services (tier 1 and 2) over at least a 6-month period must be evidenced in the referral.

Patients with BMI 25-30 may also benefit from weight loss with regards to OSA.

Medication

Medication review and where possible reduction of medication that can exacerbate sleep apnoea and sleepiness. In particular review analgesia, sedatives, gabapentin, pregabalin.

Smoking

If the patient is a smoker, then evidence that they have been given smoking cessation advice in the previous 6 months.

Alcohol

If alcohol intake is greater than 14 units per week, then evidence that they have been advised to reduce alcohol intake within the previous 6 months.

CPAP

The referrer should confirm that the patient will accept and is likely to tolerate treatment with CPAP. Patients should not be referred if they are either too frail to use or manage CPAP treatment, or where they are clear that the treatment would not be acceptable to them.

Driving

All patients being referred should be given driving advice. If the patient has been advised not to drive please highlight this in the referral.

Referral

Referral for Sleep Studies

Referral for sleep studies can be made via eRS once criteria are met and should be made using the Sleep Medicine Referral form (also available as an EMIS template).

Referrals will be reviewed by the BNSSG Referral Service and returned if criteria are not met.

Please manage patient expectation. The wait time for a first appointment may be several months and then a further wait before a CPAP trial (if appropriate and criteria are met) can commence.

In order to have an effective pathway and to manage numbers better, several elements would help the delivery of the service and these must be addressed in all referrals for sleep studies

Referral for CPAP

Referrals for CPAP can only be made via the Sleep Studies pathway.

Patients can then only be considered for CPAP treatment once OSA has been confirmed. Access to CPAP is subject to the Assessment Referral & Treatment for Sleep Apnoea Criteria Based Access (CBA) Policy.

Snoring

Please note that referrals should not be made for snoring alone. Referrals are subject to an exceptional funding policy and will be returned to the referrer. See the Snoring page for further details.

Paediatric Referrals

Paediatric referrals (under 16) should be referred to the Bristol Children's Hospital respiratory clinic via eRS.

CPAP problems

If patients are having problems with their CPAP device, please contact the Sleep Unit at the BRI as soon as possible.

Patients should be advised to contact them and let them know their name, hospital number and date of birth:

• 0117 342 1640 (voicemail)
• sleepunit@uhbw.nhs.uk

Additionally, they have a drop-in clinic for replacement parts only on Thursdays from 9am to 11am at B301 within the BRI. For anyone with problems or concerns, please advise patients to email/phone first.

Resources

(1) NICE - NG202 - NICE guidance for OSA - August 2021

(2) Clinical Knowledge Summaries - Obstructive Sleep Apnoea

Efforts are made to ensure the accuracy and agreement of these guidelines, including any content uploaded, referred to or linked to from the system. However, BNSSG ICB cannot guarantee this. This guidance does not override the individual responsibility of healthcare professionals to make decisions appropriate to the circumstances of the individual patient, in consultation with the patient and/or guardian or carer, in accordance with the mental capacity act, and informed by the summary of product characteristics of any drugs they are considering. Practitioners are required to perform their duties in accordance with the law and their regulators and nothing in this guidance should be interpreted in a way that would be inconsistent with compliance with those duties.

Information provided through Remedy is continually updated so please be aware any printed copies may quickly become out of date.