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How to manage obesity hypoventilation syndrome

How to manage obesity hypoventilation syndrome

Toni Jenkins, an independent bariatric nurse consultant and obesity nurse specialist, discusses how to help patients with obesity hypoventilation syndrome

Obesity hypoventilation syndrome is a condition in which people with obesity fail to breathe properly, resulting in low oxygen and high carbon dioxide levels in the blood. It is commonly associated with obstructive sleep apnoea hypopnoea syndrome (OSAHS), where the upper airway narrows or closes during sleep when muscles relax, causing under breathing (hypopnoea) or temporary cessation of breathing (apnoea).

The person fully or partially awakes to stop these episodes, leading to disrupted sleep and potentially excessive sleepiness.1 OSAHS can have a major impact on safety for the patient and those around them.

Practice nurses may be the first clinicians to identify the syndrome by spotting subtle signs during a routine consultation for other reasons. A prompt diagnosis and early management can be vital, with initial issues being physical, psychological or social.

Signs and symptoms of OSAHS

The patient may report, or exhibit, any of the following:

  • ‘Nodding off’. They may appear drowsy during the consultation or have been asleep in the waiting room. When this happens both adults and children can sometimes be assumed to be slow or inattentive.
  • Clumsiness, including stumbling, bruising and injuries
  • Poor concentration span
  • Depression

It is essential to do a full sleep assessment to see if the patient falls into a high-risk category (or may simply have had bad nights or be caring for a small baby or a new puppy!)

Sometimes the patient’s partner may comment on signs and symptoms they have observed1 including:

  • Snoring
  • Apnoea
  • Nocturia (waking from sleep to urinate)
  • Choking during sleep
  • Cognitive dysfunction or memory impairment: ‘They have a memory like a sieve’.

The patient may additionally complain about:

  • Feeling tired despite sleep
  • Waking with a headache
  • Feeling shattered, exhausted and experiencing tired all the time syndrome (TATT)
  • Insomnia or repeated sleep interruptions.

Some of these symptoms may be related to conditions such as depression, prostate issues and dementia. However, if three or more of the above are present, a patient should be deemed at risk and considered for sleep studies.

Many practice nurses are familiar with obstructive sleep apnoea (OSA) and it is easy to assume a patient has OSA. Some patients will self-diagnose and may even purchase a continuous positive airway pressure (CPAP) machine. This will help OSA but not OSAHS.

Should we refer or can we help in the community?

Practice nurses’ experience equips them to discuss appropriate lifestyle changes with people living with OSAHS, including support and advice regarding:

  • Weight management
  • Smoking cessation
  • Reduction in alcohol intake
  • Improving sleep hygiene.

Ultimately, referral may be needed as the consequences can include:

  • Death from complications associated with hypoventilation apnoea
  • Driving or burning accidents caused by falling asleep High risk during general anaesthesia
  • Poor Covid-19 outcomes.

When to refer to sleep services

  • During the Covid-19 pandemic, many services have been reduced or even suspended altogether. Sleep studies always have significant waiting lists and the pandemic has added to this. However, nurses should not be discouraged from referring, especially patients with a history of the following:1
  • Obesity or overweight (especially in pregnancy)
  • Hypertension that doesn’t respond to drug treatment
  • Type 2 diabetes
  • Cardiac arrhythmia
  • Cerebrovascular accident or transient ischaemic attack
  • Chronic heart failure
  • Moderate or severe asthma
  • Polycystic ovary syndrome
  • Down’s syndrome (adults with Down’s are predisposed to OSAHS)
  • Non-arteritic anterior ischaemic optic neuropathy (sudden unilateral loss of vision due to decreased blood flow to the optic nerve).

Patients may have to wait and their expectations need to be managed. Patients can be prioritised for urgent referral, but will still require support while they wait.

How do we prioritise patients?

We should prioritise people with suspected OSAHS for rapid assessment if any of the following apply:

  • They are driving for a living or operating forklifts
  • They have a job requiring careful vigilance to maintain safety, eg operating large machinery.

Ultimately this may lead to patients being referred to the DVLA if their driving is impaired. This can cause a breakdown in trust between patients and healthcare professionals, so it is essential to explain why a commitment to treatment is necessary.

Patients generally downplay sleepiness if it affects their independence or may lead to loss of income. This is entirely understandable, but they need to understand the safety implications.

Treatment for OSAHS

The only effective treatment is significant and sustained weight loss. Obesity is multi-factorial, and no clinician would genuinely believe that weight loss (or maintenance) is easy.

In an ideal world, patients would be confident that their practice nurses and/or GPs understood the difficulties and were empathetic and not judgmental.

What can we offer?

  • Respect and compassion
  • Empathy
  • A willingness to listen and understand lifestyle, housing and financial influences
  • Referral to sleep assessment services
  • Consideration of prescription of GLP1RA medication (liraglutide and semaglutide are available on NHS prescription for eligible patients)(2)
  • Consideration and referral to Tier 3 weight management services with potential options for bariatric surgery

Marginalisation of obese patients

Patients living with obesity or overweight often feel marginalised by mainstream health services.3 Obese patients may find that the response to every problem is to blame them for their condition and simply offer them a diet sheet. There is well-documented evidence from ObesityUK regarding such patients’ poor experiences, which leads to many simply avoiding health services due to fear of criticism.3

Unfortunately, obesity is still seen by many as a result of being greedy or weak-willed. Many genetic studies prove otherwise, including twin studies.4,5 It is now accepted that obesity is a chronic disease.6

Surgery risks for patients with OSAHS

Patients must be advised that they are at increased risk during general anaesthetic, and this must be carefully communicated when patients are referred for elective or emergency surgery.

Patients must also be informed that any surgery should take place in a hospital with significant expertise in managing patients living with obesity and that full HDU facilities should be available.

Unfortunately, NHS bariatric surgery is difficult to access with private surgery being expensive and overseas options can seem very attractive. Overseas surgery is often very high risk unless it occurs in a unit equivalent to a UK bariatric centre of excellence. Surgery should not take place in clinics primarily established to provide aesthetic surgery. Specific reassurances should come from the surgeon rather than an agent or patient advisor.

Improving health outcomes

Fortunately, hypoventilation syndrome linked with obesity is not common. Nonetheless, spotting the red flags can make a significant improvement in the health outcomes of patients and most will be very grateful to find a clinician that listens and does not dismiss their concerns by simply telling them to go on a diet. Lifestyle changes are essential with every treatment, but patients will be more likely to work with clinicians if they are respected and actively involved in planning to improve their health.

Toni Jenkins is an independent bariatric nurse consultant and obesity nurse specialist at accredited healthcare training provider ECG Training

Resources and further information


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