This page provides an overview of how muscle weakness affects the lungs in ALS patients, strategies for managing breathing symptoms, and suggestions for planning for the future. Weekly updates with details, tips and techniques, treatment options, and information about new FDA-approved equipment for lung expansion and secretion management can be found in the “Breathing Lessons” column on this site.
How ALS Affects Breathing
The diaphragm is the major muscle of inspiration, doing about 80% of the work of breathing. Intercostal muscles, which are between the ribs, help expand the ribcage. The diaphragm muscle contracts and moves downward and the ribcage moves outward, allowing air to freely flow into the lungs.
When you exhale, the intercostal muscles contract to move the ribcage inward. The abdominal muscles, located just below the diaphragm, contribute to exhalation by pushing the diaphragm up and stabilizing the ribcage.
If you place your hands over the lower part of your ribs and stomach you can feel this dynamic action.
The brain communicates with the lung muscles, sending messages along nerves to trigger inhalation and exhalation. In automatic breathing, the brainstem, spinal cord, motor neurons, and respiratory muscles work in a feedback system to ensure air moves in and out of the lungs without our having to think about it.
During active breathing, when we initiate a breath, the motor cortex and cerebellum direct the lung muscle movement we desire.
In ALS, the nerves which send the signals from the brain to the muscles of respiration are lost. Breathing weakens over time since these muscles are receiving signals from fewer and fewer nerves.
The disruption of neuronal communication from brain to muscle begins to occur even before you experience changes in breathing. Healthy lungs maintain considerable reserves, so muscle weakness may occur before it can be measured by pulmonary function testing or experienced as shortness of breath.
There are several breathing techniques that can be practiced early in the disease process. The goals are to maximize lung function and maintain lung health. You may be doing these lung exercises already if you practice yoga, Pilates, Qi gong, tai chi, or other forms of movement that incorporate breath work.
Many of us breathe at half of what our lungs can actually take in, our lung capacity. If you are a sedentary person, or if weakness in your feet and legs has reduced your ability to exercise, your breathing will be shallow. Stress also contributes to shallow breathing. You may find yourself unconsciously holding your breath as you try new and difficult tasks while adapting to life with ALS.
Deep and focused inhalation and full exhalation, directing your breath to different areas of the lungs, will best utilize your lung capacity. Taking deep breaths will also stretch the muscles between the ribs, keeping them supple. Focused breathing helps relieve tension, promotes relaxation, and can give you a sense of well-being. Step-by-step instructions and short videos on various ways to maximize your breathing will be posted in “Breathing Lessons.”
A low-tech way of maximizing your lung capacity is “breath stacking” using a manual ventilation bag – the ones used for pulmonary resuscitation – adapted with corrugated tubing and a mouthpiece. Here, the ventilation bag is used to hyper-inflate the lungs to their fullest capacity when you can no longer do so on your own. In this technique you take in a deep breath and trap the breath in the lungs by closing your vocal cords. Then, while squeezing the bag (or coordinating with a partner), you “stack” another breath on top of the first, trapping it in the lungs. Then you stack a third breath on top of the second one. Hold your breath for 3 to 5 seconds. Then fully exhale. After a series of these breaths you may find that your breathing is easier and your voice is stronger. Combined with relaxed diaphragmatic breathing and “huff coughing,” breath stacking becomes “active cycle breathing” an effective, low-tech way of maximizing your lung’s potential. You can find a short video demonstrating these techniques in “Breathing Lessons.”
A high-tech way of breath stacking utilizes the Cough Assist machine (Philips Respironics). Instead of squeezing a bag to pump air into the lungs, you use a hand or foot switch to activate a pressurized breath. Then you stack breaths using the same technique described above. With the Cough Assist you can set the pressure at a level that is comfortable and effective for you. The Cough Assist, as its name implies, also assists in producing a stronger cough than you can on your own with weakened lungs.
Of the symptom-management strategies currently available for ALS patients, bi-level positive airway pressure has been shown to improve quality of life and increase life expectancy for people with ALS.
Bi-level positive airway pressure breathing, or BiPAP, is a registered trademark of Philips Respironics. It is often used the way Kleenex is used to refer to tissue or Xerox is used for photocopying, because it was first on the market. Other terms for BiPAP are simply bi-level assisted breathing, noninvasive positive pressure ventilation (NIPPV or NPPV), noninvasive ventilation (NIV), or pressure support ventilation (PSV). All of these terms describe an assisted breathing technique that uses two pressure levels: A higher pressure is used to expand the lungs on inhalation, and then the pressure drops to a lower level that maintains some pressure in the lungs while reducing the work it takes to exhale against a pressurized breath.
The broad goals of bi-level assisted breathing are to:
• Replace lung volumes lost to disease,
• Improve lung function by moving oxygen into the lungs/blood stream and carbon dioxide out,
• Rest the diaphragm (which can get overworked as it gets weaker), and
• Help you get a restful night’s sleep by supporting your breathing while you recline.
Bi-level assisted breathing is recommended when your symptoms and/or lung-function testing show that your lungs are getting weaker. When you take in a breath, the machine delivers a larger breath to ensure you receive adequate lung volumes. In this way it supports your spontaneous breathing.
Bi-level assisted breathing devices designed for people with progressive lung weakening diseases (ALS, muscular dystrophies) include a “back-up breathing rate.” This assures that if your lung volumes drop to very low levels, the machine will sense this and deliver a pressurized breath to you.
Assisted breathing with a bi-level device is achieved using a mask that fits over the nose, or over the mouth and nose, or with cushions that fit into the nose.
Assisted breathing in ALS will be a topic with numerous entries on “Breathing Lessons” as new strategies for breath delivery, new equipment, and new modalities make their way into the market.
Mechanical ventilation is used to describe assisted breathing or total ventilatory support that is delivered to the lungs through a breathing tube (endotracheal tube or tracheostomy tube.) This is an option when noninvasive bi-level assisted breathing is no longer effective at expanding the lungs and keeping you comfortable. Mechanical ventilation will not stop the progression of ALS, but it will prolong life by assuring your lungs will expand, oxygen levels will be maintained, and carbon dioxide will be eliminated. The decision to be on life support is a personal one and should be discussed regularly with family members, trusted friends, and your physician. The benefits and challenges of mechanical ventilation should be discussed in detail with your respiratory therapist, nurse, and physician.
If you choose mechanical ventilation, you can also choose at what point you want it discontinued. With the support of palliative care physicians and nurses and a knowledgeable hospice agency, removal of life support can be dignified and comfortable.
ALS is a devastating diagnosis as there is no cure. However, there are supportive treatments including breathing support. It is important to plan ahead and make decisions early in the disease process about how much or how little treatment you want to accept.
Your decisions should be reviewed regularly with your physician and members of a multidisciplinary care team during clinic appointments.
Adopting breathing support early in the disease process makes it easier for you to adjust to it. Beginning your breath support with no or low-tech techniques and moving to bi-level assisted breathing is an easier transition than starting mechanical support late in the course of ALS. It is difficult to adapt to assisted breathing if you wait until your lungs are very stiff and you are air hungry.
Being proactive will give you more control over when and how your breathing will be supported. Unplanned emergency hospital admissions are not the best time to make decisions about invasive or noninvasive ventilation. If you have not made your wishes known, preferably in writing, others will make decisions for you. This is also your choice. Making no decision is in fact making a decision to let your family or physicians guess what you would want or decide what is best for you.
Tools for decision making in ALS will also be a future feature in the “Breathing Lessons” column.
© Lee Guion MA, RRT