Q: Does ALS affect breathing? A: Most people with ALS will, sooner or later, have some difficulty breathing. This is due to the progressive deterioration of the respiratory muscles – which move air in and out of the lungs – that are weak. Some patients develop breathing problems early in the course of the disease, but some develop them later. Unless there is a combination of other diseases, breathing problems do not begin directly involving the lungs themselves. The lungs may be affected later in life, with collapsed airways or atelectasis accompanying muscle weakness. Q: What happens if the respiratory muscles are too weak to keep enough air moving in and out of the lungs? Does it cause respiratory arrest? A: No. Respiratory impairment in ALS is a gradual process. Respiratory function is lost so slowly that the patient may not even realize it is happening. (Note: Because respiratory impairment is insidious and not easily recognized, some patients may not be aware of it even when it is already severe. As this condition progresses, respiratory failure may occur suddenly, and some patients do experience this. (Therefore, if possible, try to visit your doctor for checkups in 3 to 6 months and respond proactively.) Q: How should I tell if I have respiratory impairment? A: Patients with ALS who can still exercise or operate a manual wheelchair may feel short of breath during these procedures. Shortness of breath is more common when the patient is lying down (sitting breathing), but this phenomenon is less easily recognized. Weakened respiratory muscles are further affected by gravity when in a horizontal position (lying flat). Patients with poor respiration feel anxious when lying down. As the respiratory muscles weaken, their function of delivering oxygen to the lungs and expelling carbon dioxide is progressively impaired. Especially during sleep, the effort in breathing is reduced compared to when we are awake. If there is a lack of oxygen while sleeping, problems such as restlessness, shallow sleep, and frequent or easy awakening can occur. However, these breathing problems are still not easily recognized unless a respiratory physiology examination is performed. Patients may simply feel that they are not sleeping very well or that they tend to nod off and get sleepy during the day. Some “slowness” or “confusion” in thought processes may be noted, or headaches may occur upon awakening. These are thought to be caused by carbon dioxide buildup. Q: Are there any medications that can make breathing problems worse? A: Yes. Unfortunately, they are often prescribed for anxiety and poor sleep – and our patients likely have unrecognized hypoventilation (insufficient ventilation) problems. Almost all medications prescribed for insomnia or anxiety suppress breathing and affect blood oxygen and carbon dioxide concentrations in ALS patients. I do not believe that all of these medications are safe, especially if the underlying breathing problem is not treated. Assessing insomnia and anxiety problems in ALS patients is best started with breathing problems. If respiratory problems are treated or respiratory function is monitored, then consider anti – anxiety medications and use caution if how needed. Q: What should I do if I suspect a breathing problem? A: First of all, of course, you should see a doctor. A number of tests, some simple and some complex, need to be done to check the status of respiratory function. A simple test is to blow into a spirometer machine to measure the amount of gas entering and leaving the lungs. This measurement should be checked in both sitting and supine positions to determine diaphragm strength. Another test places electrodes in the fingers or earlobes to measure the amount of oxygen in the blood. The device is called a blood oxygen quantification meter. The doctor may measure the concentration of dissolved oxygen and carbon dioxide in the blood and this test is blood gas level (analysis). With symptoms of inadequate breathing, these tests may be performed during the day and the results may be normal or near normal, a condition that usually requires all-night testing. In my clinical practice, there is a low threshold for performing sleep studies or polysomnography studies. Patients are asked to spend the night in a sleep lab with electronic sensors monitoring brain waves, heart rate, respiratory activity (chest and abdomen rise and fall) and blood oxygen and carbon dioxide (sometimes) levels. Sleep studies may seem somewhat cumbersome, but are worth doing to capture the first occurrence of low oxygen levels or carbon dioxide retention during deep sleep in ALS patients. Q: What do I need to do if there is a problem with low oxygen or high carbon dioxide? A: In our outpatient clinics, we provide non-invasive positive pressure ventilation support to our patients. NIPPV allows a machine device to deliver a fixed volume or pressure of air (not oxygen, just regular air) into the patient’s lungs. There are many of these devices on the market, each with its own advantages and disadvantages, and the details need to be discussed with your doctor or respiratory therapist. ”Non-invasive” means that air is passed through the mask into the nose and/or mouth. With “invasive” ventilation, air enters the throat through a tracheotomy air incision. NIPPV does not need to be performed all the time, but is usually started during sleep and then gradually extended to daytime. Q: Is NIPPV indicated for all patients? A: No. Every patient is different, and not everyone can tolerate ventilation support. Patients who have lost teeth, have a short jaw, or have weak muscles in the mouth and throat may have problems with the mask. Q: Can NIPPV solve the problem once and for all? A: Unfortunately, no. Patients with ALS will eventually have weakened breathing muscles to the point where NIPPV will not be able to maintain breathing either. In this case, the patient may have to consider whether to switch to invasive ventilation. Pneumonectomy ventilation allows air to pass more directly into the lungs, bypassing the mouth and throat, while reducing the potential for leakage. Therefore, it will be more effective than NIPPV in the phase of severe respiratory muscle weakness.