Neuromuscular Conditions

Neuromuscular disease is an umbrella term that includes conditions that affect the nerves and muscles. This can lead to weakness of the arms and legs and of breathing muscles. Neuromuscular weakness can develop for a range of reasons – some conditions are inherited, some develop after specific infections, and some develop later in life. Certain neuromuscular diseases progress slowly over years, others can progress rapidly over months.

People who have weakened breathing muscles will not be able to breathe in enough oxygen or breathe out enough carbon dioxide. If not treated, headaches, nausea and other more serious health issues will happen.

Tests to identify breathing muscle weakness in people with neuromuscular disease can include:

  • an overnight sleep study – small sticky sensors can measure oxygen, carbon dioxide and heart rate while asleep. This can be at home or in hospital.
  • arterial or capillary blood gas testing – a blood test at the wrist or earlobe to check how much carbon dioxide is in the person’s blood.

If the tests show that the amount of oxygen is too low or the amount of carbon dioxide is too high, Home Mechanical Ventilation (HMV) will be needed to make sure the person can breathe well overnight and stay healthy.

Over time, when muscles get weaker, HMV may be needed during the day too. For some, this is only when unwell. For others, this can be for a few hours every day, during or after being active, or all day. This means that they will have the energy to do their usual activities and be less likely to be unwell.

Non-invasive ventilation (NIV) means breathing is assisted through a mask. There are many types of masks available, each with different advantages and disadvantages. A nasal mask is often preferred, as it is often the most user-friendly.

Disorders of the Nerves

Motor Neurone Disease (MND):
MND may also be referred to as amyotrophic lateral sclerosis (ALS). It is a difficult condition to diagnose due to the different symptoms presented and varying rates of decline. The average time from onset of symptoms to formal diagnosis is 14 months.  In most cases there is no known cause. There is a small percentage (around 5%) of MND cases which are familial (runs in families). The most common symptoms that develop tend to be weakness in the arms and/or legs causing unsteadiness (limb onset) or with weakness of head and neck muscles that cause speech and swallowing difficulties (bulbar onset). Most patients develop respiratory muscle weakness, which tends to happen more quickly in patients with bulbar MND. People with MND are monitored at regular intervals to test the strength of their breathing muscles and cough to determine whether HMV should be recommended.

Links to condition specific related national guidance or standards

Motor neurone disease:
For patients, families and caregivers from the MND Association

For healthcare professionals: NICE Guidelines on assessment and management – www.nice.org.uk/guidance/NG42

Spinal Muscular Atrophy (SMA):
A genetic condition with progressive muscle weakening, resulting in movement problems. Typical symptoms include: floppy or weak arms and legs, bone & joint problems (scoliosis), swallowing or breathing difficulties. There are several types of SMA:

Type 1: Develops in babies less than 6 months old and is the most severe
Type 2: Appears in babies aged between 6 & 18 months
Type 3: Develops in toddlers over 18 months and is the least severe affecting children
Type 4: Affects adults and usually only causes mild problems

Respiratory monitoring is essential and both HMV and cough augmentation are often required.

Links to condition specific related national guidance or standards

Spinal muscular atrophy:
For patients: treat-nmd.org/wp-content/uploads/2019/06/uncategorized-A-Guide-to-the-2017-International-Standards-of-Care-for-SMA_UKEnglish_Digital-v2L.pdf

For healthcare professionals: Diagnosis and management of SMA Part 2 including Pulmonary and Acute care www.sciencedirect.com/science/article/pii/S0960896617312907?via%3Dihub

Disorders of the Muscles

Duchenne muscular dystrophy (DMD):
DMD is a rare muscle disorder but is one of the most frequent genetic conditions affecting approximately 1 in 3,500 male births worldwide. Affecting almost exclusively males, it is caused by changes of the DMD gene on the X chromosome. The gene regulates the production of a protein called dystrophin. With the advances in medical management, most boys with DMD remain ambulant for longer, require assistance with ventilation at a later age and have an increased life expectancy. There is a large variation in the age that ventilator assistance is required ranging from early teens to age 30’s. In addition to home ventilation, consideration of cough effectiveness and secretion clearance is essential, as well as cardiac monitoring.

Links to condition specific related national guidance or standards

Duchenne Muscular Dystrophy:
For patients and families: DMD Guide for Families www.treat-nmd.eu/downloads/file/standardsofcare/dmd/uk_english/UK2018FamilyDMDGuide.pdf

For healthcare professionals:

Becker’s muscular dystrophy (BMD):
BMD is a less severe dystrophinopathy affecting almost exclusively males. The onset of symptoms appears later, and not everyone requires ventilatory support. Respiratory monitoring is required along with consideration of cough augmentation & cardiac reviews.

Limb Girdle Muscular Dystrophy (LGMD):
A large group of diverse genetic disorders in which there is weakness and wasting (atrophy) of the muscles connected to the limb girdles. Symptoms usually occur in late childhood or early adulthood. Some patients with LGMD will require HMV and respiratory monitoring is required.

Myotonic Dystrophy:
Myotonic Dystrophy (MD) is a form of muscular dystrophy, a group of genetic disorders that cause progressive muscle loss and weakness. Onset is typically in the 20s and 30s. There is no cure. Six monthly pulmonary function tests and sleep studies are recommended with the provision of CPAP, HMV and cough augmentation as indicated.

Links to condition specific related national guidance or standards

Myotonic Dystrophy:
For healthcare professionals: Consensus-based care recommendations for adults with myotonic dystrophy type 1 – cp.neurology.org/content/neurclinpract/8/6/507.full.pdf

Charcot Marie Tooth (CMT):
Charcot-Marie Tooth disease is a hereditary motor and sensory neuropathy of the peripheral nervous system characterised by progressive loss of muscle tissue and touch sensation across various parts of the body. Symptoms usually begin in childhood or early adulthood. Ventilatory support is required in only a small percentage of patients with CMT

Guillain Barre Syndrome (GBS):
Guillain Barre syndrome (GBS) is a rare but serious condition affecting the feet, hands and limbs causing numbness, muscle weakness, pain and sometimes paralysis. It occurs as a result of the person’s own immune system harming their body’s nerves. Most people eventually make a full recovery although some people are left with long-term problems.

Links to condition specific related national guidance or standards

Guillain Barre Syndrome:
For healthcare professionals: Diagnosis and management of Guillain–Barré syndrome in ten steps – https://www.nature.com/articles/s41582-019-0250-9

Post-Polio Syndrome:
Polio is a viral infection that used to be common in the UK but is now rare. Polio symptoms include paralysis and muscle weakness which usually improve or remain stable. Post-polio syndrome is where symptoms develop or worsen generally 15 or more years after the infection. This can lead to breathing and swallowing difficulties which may require ongoing ventilatory support.

Links to condition specific related national guidance or standards

Post-polio syndrome:
For caregivers: Post-Polio Health Care Considerations for Families & Friends – post-polio.org/wp-content/uploads/2020/05/PostPolioHealthCareAll.pdf

For healthcare professionals: European Federation of Neurological Societies guideline on diagnosis and management – https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1468-1331.2006.01385.x

Critical Illness Neuropathy:
Critical illness neuropathy or ICU neuropathy is the acute or subacute onset of widespread symmetrical weakness after critical prolonged illness such as multi-organ failure or sepsis. This can lead to ongoing need for ventilatory support.

Patient Stories:
Questions you Might Ask your Clinician:

We have included below some questions which you might like to ask your clinician. We have included responses at the request of our patient representatives. However, please note you should always refer to your clinician if you have any concerns.

Your HMV Clinical Team

The Home Ventilation Team is available to support the respiratory monitoring phase, when you start HMV, and for monitoring your changing health, providing supplies and training, and troubleshooting and supporting you at every stage.

They are often a multidisciplinary team with nurses, physiotherapists, physiologists, admin & support workers.

They will have a wealth of knowledge and experience with the equipment and options available, and will talk with you about your health, your needs, your test results and the treatments and choices available with you to develop a personalised, plan together.

They may be able to monitor your usage, mask fitting and the settings effectiveness remotely, but they need you to advise tell them of any changes in your symptoms and circumstances.

Working together will make sure you have what you need to take care of your health. In any team, you need to give and receive respect, speak openly and listen well, talk about any problems and work to solve them, and build trust between each other.

Please contact your team if you have any worries or questions.

Why do I need to use a ventilator?
As neuromuscular disease affects your muscles, you may not have the muscle power to breathe on your own.

HMV works by pushing air into the lungs at the right pressure for you to make sure you’re taking deep enough breaths. With each breath, your body needs to take in enough oxygen into the blood and get rid of carbon dioxide. If you’re not getting enough oxygen or getting rid of enough carbon dioxide, you may start to get symptoms such as headaches, daytime sleepiness and poor concentration.

Due to the normal effects of sleep on muscle function, breathing problems due to muscle weakness are often exaggerated in sleep. Not being able to breathe properly at night prevents your body from being able to perform its vital functions and recharge for the next day. HMV will support the muscles while you’re asleep, making sure that you’re breathing well.

If you cannot breathe properly during the day, you may not have the energy to do many of the things that you normally like to do. HMV can give you more energy in the day, improve the quality of your sleep and help reduce breathlessness and risk of infections and other issues.

How many hours a day should I use the device?
You need to use the right amount for your body. Everyone is different and your needs may change over time. Some people need to use it every night and for as many hours as you sleep.

Others need to use it while they sleep and when they rest during the day and some may need to use it constantly in the day and night. It may take time to become comfortable and familiar with using HMV.

Talk to your clinician about your symptoms and keep them updated whenever you feel that something has changed.

Watch out for headaches, daytime sleepiness or feeling less alert & focused which can all be signs of too much carbon dioxide in your blood. These would show that either increased use or slightly higher pressures may be needed.

Palpitations, finger tingling and/or light-headedness could be signs of over-ventilation. This could mean that you need to use your HMV less, or that lower pressures are needed. Contact your team immediately to talk about what needs to happen.

Read more about palpitations here https://www.nhs.uk/conditions/heart-palpitations/

I struggle to sleep with the machine on, can I use it in the day instead?
When you first start using your machine, you could use it in the day to get used to it, however the aim is always to build towards using during your sleep, as this is when you need the support the most. If you have had a sleep study that showed dips in your oxygen at certain times, this shows when your body needs HMV most. HMV’s job is to prevent those dips, but it can’t do that if you’re not using it when they usually happen.

If you are struggling to sleep with the machine on you should keep trying, but if it doesn’t get easier to sleep using your HMV, contact your specialist team. Talk to your clinician about what is making it hard to sleep with. They will check that everything’s okay with the machine, that the mask fits you well and is comfortable, whether the settings can be adjusted to make it work better for you, and if there’s anything else they can do to help.

What if I have problems with my machine?

You will be given contact details for your HMV specialist team who will be able to provide advice and support or replace any faulty equipment.

Most devices have a manufacturers’ manual which can be useful to learn more about what to watch out for. Many are also available online on the manufacturer’s website.

Can I have a night off?

You will get the best effect from your machine if you use it every time you sleep. However, if you are regularly using your machine but need to take a night off due to personal circumstances, this may be possible for some people, but for others could be unsafe. You should always discuss this with your HMV specialist team in advance as everyone’s circumstances are different, and the risk is higher in patients who need HMV in the daytime and night-time.

Talk to your clinical HMV team about the reasons for needing a night off. There are different mask options or devices with a battery back-up to enable camping trips or times away from home.

Can it be risky to have extra oxygen when you have neuromuscular disease?

YES.

Additional oxygen is not recommended with neuromuscular disease and can be dangerous, as it can upset the balance of oxygen and carbon dioxide (waste gas) in your body. Breathing higher levels of oxygen can lead to a build-up of carbon dioxide in your body which can be harmful.

Carbon dioxide retention symptoms include: headaches, nausea, feeling tired even after rest, daytime sleepiness, confusion & poor memory/concentration.

Speak to your clinical team immediately if you experience these symptoms.

Oxygen may sometimes be used with caution when an individual’s oxygen levels are low such as when someone has pneumonia or COVID infection and this should be entrained within the HMV circuit.

However, an emergency oxygen mask joined to an oxygen cannister should not be used. This can be extremely dangerous, and even deadly to someone with an NMD.

As neuromuscular diseases are often rare conditions, not all healthcare professionals will be aware of the risk involved in using extra oxygen and therefore your specialist team may provide you with an oxygen alert card which explains this.

The exception is on flights where there is a lower oxygen level in the pressurised cabin and supplementary oxygen may be advised. Make sure that you, your family and care team are aware of the risks regarding oxygen use and talk to your HMV team about how to make sure you can do this safely.

How does HMV support breathing?

Home mechanical ventilation uses air at high pressure to inflate the user’s lungs, and then lowers the pressure to allow the user to breathe out. A lower pressure is delivered on the out breath to prevent the airways from closing or collapsing. This can also stop the muscles around the lungs from becoming overtired and in some cases stop them from weakening as quickly.

The rhythm of the breaths delivered by the machine can respond to the user’s breathing rate or can be set on the device. By making sure that a person’s lungs are fully inflated on the in breath, HMV makes sure that enough oxygen enters all parts of the lungs with every breath. Keeping the airways open makes sure that the user can breathe out well enough to get rid of enough carbon dioxide with every breath.

People with neuromuscular conditions usually do not need a high pressure on the out breath to keep the airway open, and if this exhale pressure (EPAP) is too high, it can be difficult for the user’s muscles to push against this pressure to breathe out.

Non-invasive ventilation is designed to work with the muscles you have, creating a system that makes breathing happen more effectively. As your muscles weaken over time, your ventilator settings may need to change to do a little more of the work. You may also need to use your HMV for more time every day.

You cannot “wean yourself off HMV” or “do exercise to avoid becoming reliant on ventilation”. If your muscles cannot keep you breathing in enough oxygen and out enough carbon dioxide on their own, HMV is there to do that job. It will not make your muscles weaker, and your muscles will not get stronger with exercise. Avoiding HMV could make your muscles weaken faster through over-exhaustion.

By breathing well, you will have more energy to do the things you love, and less chance of needing hospital treatment for infections. It can also greatly increase your lifespan, giving you extra time with the people you love.

Why is it important to undertake respiratory monitoring in people with neuromuscular disease?

Not all patients with neuromuscular disease will require HMVV. Regular assessments with the respiratory/Ventilator specialists will allow them to monitor your lung function and identify if and when HMV may be required. Blood gas measurements allow them to look at the amount of oxygen and carbon dioxide in your blood to see how well your breathing muscles are functioning. Other tests such as breathing tests, muscle strength tests and sleep studies may also be undertaken at regular intervals to monitor your breathing and better identify when additional support may be required. Once you are established on home ventilation, respiratory monitoring will assess whether the current ventilator settings are adequate to meet your needs.

What is remote monitoring?
Some HMV machines are designed to send information daily to your specialist team, as long as you provide consent for this to happen.

Machines vary with what information they send however it often includes information about how long you have worn the machine for and whether or not your mask was fitted well. It can also identify faults with your equipment. In some circumstances, your machine settings can also be changed remotely, meaning you will not need to visit the clinic to get this done.

You should be given contact details for your clinical team to replace a faulty device or new consumables (like masks, tubing, and filters) or to discuss an issue you’re experiencing.

Does remote monitoring mean I do not need to call to tell you when I am having a problem?
No. Please call your team as soon as there is a problem.

Specialist centres will use the remote monitoring in different ways, however it is unlikely that they are regularly checking for everyday faults or problems due to the large number of patients that they will be looking after.

If you are having problems with your machine, it is always best to contact the team directly to let them know. They may then access the remote monitoring system to help with identifying the fault and/or supporting you with the problem.

If something is wrong with my machine will you know straight away?
No. It is unlikely that members of the specialist team are checking the remote monitoring system at all times and therefore it is important that you contact them directly if there is a problem with your machine so that they can rectify it as soon as possible.

What do I do if I am unwell?
Talk to your team about the best ways to take care of your health when you are unwell. Make a plan with your team detailing who to call, what you will need and when and what to do in an emergency.

  • In an emergency, call 999 or get to A&E.
  • For non-emergency medical care, call your GP or 111.

Having a plan ready means that you know what treatment to ask for and when. For example, getting antibiotics as soon as you have a chest infection can stop it from getting worse as quickly, meaning that it may be possible to handle it at home instead of in hospital.

Always take your machine, filters, tubing, and mask with you to hospital, as well as any other essential equipment you are likely to need.

Take any information that may be useful with you, for example a print-out of your HMV settings, and how oxygen can be used safely.

Useful Links

There are many online resources where people with neuromuscular disease can find support from professionals and peers. Below are some websites for groups and associations that support patients with specific conditions. We have also included links to national guidelines and standards which can be used to guide healthcare professionals.

Motor Neurone Disease:
For patients, families and caregivers from the MND Association

For healthcare professionals: NICE Guidelines on assessment and management – www.nice.org.uk/guidance/NG42

Duchenne Muscular Dystrophy:
For patients and families: DMD Guide for Families www.treat-nmd.eu/downloads/file/standardsofcare/dmd/uk_english/UK2018FamilyDMDGuide.pdf

For healthcare professionals:

 

Spinal muscular atrophy:
For patients: treat-nmd.org/wp-content/uploads/2019/06/uncategorized-A-Guide-to-the-2017-International-Standards-of-Care-for-SMA_UKEnglish_Digital-v2L.pdf

For healthcare professionals: Diagnosis and management of SMA Part 2 including Pulmonary and Acute care www.sciencedirect.com/science/article/pii/S0960896617312907?via%3Dihub

Post-Polio Syndrome:
For caregivers: Post-Polio Health Care Considerations for Families & Friends – post-polio.org/wp-content/uploads/2020/05/PostPolioHealthCareAll.pdf

For healthcare professionals: European Federation of Neurological Societies guideline on diagnosis and management – https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1468-1331.2006.01385.x

Guillain Barre Syndrome:
For healthcare professionals: Diagnosis and management of Guillain–Barré syndrome in ten steps – https://www.nature.com/articles/s41582-019-0250-9

Myotonic Dystrophy:
For healthcare professionals: Consensus-based care recommendations for adults with myotonic dystrophy type 1 – cp.neurology.org/content/neurclinpract/8/6/507.full.pdf