What Is BiPAP?


BiPAP is a non-invasive ventilatory assist machine. Non-invasive ventilation (NIV) machines are those that can help breathing without requiring a tube inserted into the persons airway. By pushing air into the lungs through a mask worn over the nose, NIV assists breathing. This technology was developed in the 1980's to help people with sleep apnea, a condition where the airway collapses during sleep causing the person to stop breathing repeatedly. By pushing air in, the machine keeps the airway "inflated" so it won't collapse. This is CPAP, Continuous Positive Airway Pressure.

In the 1990's computer technology added a new dimension to NIV. Now the machine could push air in until a preset pressure was reached, then reduce the pressure to allow the person to exhale easily. Repeating this cycle made breathing more comfortable and suitable for people with neuromuscular diseases who could not exhale against the higher pressure. This type of machine was sold by Respironics using the brand name BiPAP (Bilevel Positive Airway Pressure). Like the brand name "Kleenex", BiPAP has become the common name for all such products.

BiPAP is a ventilatory assist machine, but it is not a full featured traditional ventilator. A ventilator can do everything BiPAP does but a BiPAP can't do all the things a ventilator can. There are several critical distinctions between BiPAP and a traditional ventilator:

bullet BiPAP is "non-invasive", requiring only a mask that can put on or taken off as needed. The acronym "NIV" (Non-Invasive Ventilation) is used to differentiate traditional, trached ventilation from CPAP and BiPAP. A traditional ventilator is usually "invasive" meaning it requires that a tube be put down your throat or through your neck (tracheostomy) into the lungs. The tube remains in place as long as the patient needs to use the ventilator even if they reach a point where they can be off the ventilator for hours at a time. A growing trend is to use a traditional ventilator with a mask or mouth held tube, giving the noninvasive benefits of BiPAP as well as the added settings available with a vent. This option also makes the transition to trach ventilation easier if it becomes necessary. Getting insurance coverage for an expensive vent to be used for BiPAP is likely to be difficult however.
bullet BiPAP is not generally considered "Life Support Equipment." A ventilator can be set to completely take over breathing, BiPAP can only assist the breathing.
bullet A ventilator is generally set to deliver air according to volume. It pumps air in until a certain volume has been reached, then releases it.BiPAP delivers air according to pressure, stopping when it senses resistance that tells it that the pre-set amount of pressure has been met.  That is a technical difference that probably means very little in how it feels to be on a ventilator versus BiPAP. It may however affect how well lung function is maintained. A volume based air delivery will continue to inflate lungs fully and help prevent atelectasis (loss of the ability of the little air sacs at the furthest reaches of the lungs to expand) and pneumonia. A pressure based delivery system will sense resistance and not try to push air into stiff or clogged air sacs and therefore won't be as helpful in keeping them working.
bullet Long term ventilator patients often are fitted with trach tubes that allow them to eat and even to speak, but this is not always possible for ALS patients. Because it does not require a trach, BiPAP does not interfere with speech or swallowing.
bullet ALS patients often reach the point of not being able to cough effectively. With a ventilator and trach, secretions can be removed by passing a suction tube through the trach to remove secretions. If suctioning is needed by patients using BiPAP, the tube has to be passed through the nose or mouth.
bullet The presence of the trach increases the risk of lung infections because it bypasses some of the normal protective barriers. Use of BiPAP also creates some increased risk for lung infections and sinus infections.

Return to top.






What is BiPAP used for?


BiPAP (and its predecessor, CPAP) are most commonly used for people with sleep apnea or with hypopnea.
bullet Obstructive Sleep Apnea (OSA)
The more commonly seen and therefore well known apnea is obstructive. The muscles of the soft palate and throat weaken and the upper airway is narrowed or even collapsed when the muscles relax as the patient falls asleep. That blocks the airway and the patient wakes up repeatedly, often not aware that the reason he is awakening is because he quit breathing. Some people find they feel startled or even panicky with these awakenings, but other are so tired and groggy from lack of sleep they may not even be aware they are waking up over and over. Snoring generally occurs, but it is possible to have apnea and not snore at all. Similarly, obstructive sleep apnea is often associated with obesity however there are apneaics who are of normal or low weight.
bullet Central Apnea
Another type of apnea that can occur is "central apnea" in which the little nerve center in the brain stem that is supposed to regulate when we take a breath and how long we hold it, fails to work properly when we fall asleep. This can be a problem directly with the nerve center or with the motor nerves that carry the message to the muscles used in breathing. Even though we think of breathing as something that is continually on "autopilot", sleep seems to somehow interfere with the autopilot mechanism and apnea occurs. All it takes is a little stimulation to get breathing going again -- for babies with sleep apnea, just jiggling the crib is often all it takes. For adults, a spousal elbow in the ribs usually does it! BiPAP gives a breath and that breath is either enough stimulation to get you to breathe again or is enough to tide you over until you do breathe again.
bullet Hypopnea
A third possibility is that the muscles of respiration are weak and during sleep when breathing is normally shallower, breathing becomes too shallow. The patient doesn't stop breathing but breathing is inadequate. BiPAP can be used to increase the volume of air taken in without increasing muscle effort.

How does this apply to ALS?

All three of the problems discussed above can occur in ALS. Bulbar weakness (weakness of the muscles controlled by the cranial nerves that arise from the bulb-shaped medulla portion of the brainstem) causes swallowing and speech problems and may also allow collapse of the upper airway during sleep when muscles relax. This results in obstructive apnea. If ALS affects the motor pathways the brain stem uses to send the impulses to trigger breathing, central apnea can occur. And of course ALS can affect the muscles used in breathing and cause hypopnea. Hypopnea is probably the most common problem in ALS but it certainly is possible for a combination of these problems to occur in ALS.

Whether it is a form of apnea or hypopnea, the patient does not get good quality sleep. Quality of sleep is not just dependent on the total number of hours, but also how that time is broken up by awakenings. In order to feel rested, it is necessary to get blocks of sleep that lasts at least 90 minutes -- that is when REM sleep occurs and REM sleep is apparently the stage of sleep where the brain has a chance to "recharge" itself. Without this good quality sleep, the patient becomes increasingly tired, has trouble staying awake during the day (yet has apnea and awakens if he falls asleep), finds it harder think clearly, concentrate, remember. Depression is very common. In addition the mental effects, the lack of sleep begins to affect physical health too.


Return to top.






How do I know if I would benefit from BiPAP?


Like everything else with ALS, the onset of breathing problems can vary from patient to patient. Commonly the person with ALS finds he gets a little short of breath when lying on his back. About the same time, it is likely he will notice that he becomes short of breath easily -- with exertion especially, but also after eating, when overly tired, or just in a stuffy room.

This gradually worsens and lying flat, whether on his back or side, becomes a problem. It becomes necessary to use several pillows or even begin sleeping sitting up or in a reclining chair. The human body was designed to breathe best when upright. Lying down makes it harder for the rib cage to move. Unfortunately, the human body was also designed to sleep lying down. Sleeping sitting up is not comfortable for anyone and it is really unhealthy for someone with ALS. If you sleep in a sitting position and then spend your entire day sitting, you will develop bed sores, more appropriately called pressure sores, on your tailbone and other bony points on your backside. This is not a possibility, it is an inevitable result if you spend 24 hours a day on your butt! People with strokes or spinal cord injuries may be unaware that they are developing a pressure sore. You won't be because you haven't lost feeling, and pressure sores HURT! Also, constant sitting, even with your feet elevated, will not allow good circulation to your legs and swelling will be another problem. (Click here to see info on "Swelling of Feet and Legs")

Using a BiPAP will allow you the wonderful and necessary pleasure of lying down, stretching out, turning on your side, and sleeping soundly.

A less obvious sign of hypopnea may be noticed before actually feeling short of breath. Even in healthy people, breathing is shallower when we sleep. For people with ALS, that little extra drop in volume can mean trouble since they are breathing shallowly to start with. When hypopnea occurs, you notice that you are more and more often waking up in the morning with a headache that goes away when you get up. The reason for this is that shallow breathing begins to affect the ability to "blow off" carbon dioxide. The excess CO2 causes blood vessels in the brain to dilate which in turn leads to a headache. The headache goes away when you wake up and start moving around because you breathe more deeply when awake and blow off the CO2.

We often associate that type of headache with "sleeping wrong" and tight muscles in the neck. Getting up also eases that muscle strain so differentiating between the two types of headaches is blurred. Try this: the next time you awaken with a headache, stay put. Don't change position, just begin taking deeper breaths. If the headache eases it is due to hypopnea and BiPAP will help. Untreated, the hypopnea will get worse and you will begin to wake up more and more tired and groggy. You may begin to feel confused and disoriented in the morning and tired all day.

Although hypopnea is the more common problem with neuromuscular diseases, apnea can also occur. It can be really obvious that something is wrong. You find yourself drifting off to an exhausted sleep only to be jolted awake by a wave of feeling that includes a galloping, thudding heartbeat, weakness, dizziness, and a generally panicked feeling. This happens over and over until you finally are so exhausted you sleep through it. It can also be much more subtle. You wake up frequently and may or may not remember doing so.  Either way, in the morning you know you just didn't get enough sleep. You are tired all day, doze off frequently, have headaches, feel half sick from exhaustion, have a poor appetite, can't think or remember as well as you did, are emotionally on thin ice, and feel an undercurrent of constant anxiety. In short, you have all the problems associated with sleep deprivation even though you may seem to spend hours in bed and hours dozing in your chair.

If you can't breathe well enough lying down to get a good night's sleep, are sleeping sitting up, having morning headaches, or find yourself waking up frequently, or just feel like you aren't getting enough sleep, it is a pretty clear indication you have reached the point where BiPAP could really improve your quality of life. I sleep better when I am wearing it, but that is only part of the benefit. Since I began using BiPAP at night, my days have improved drastically. Not only do I have less trouble breathing during the day, I eat better, choke less, feel stronger - mentally, physically, and emotionally, have more stamina, am not cold all the time, my heart is not pounding along at 100 beat's per minute, and, in general, feel like I took a giant step back from death's door.

Return to top.






How do I get BiPAP?


You have to have a physician's order (prescription) to get a BiPAP machine even if you do not plan to seek insurance reimbursement so the first step is . . .
bullet Finding a Doctor

Unfortunately, finding someone who is "cross trained" to understand both the effects of neuromuscular disease on respirations and the respiratory assistance machines available can be hard. The neurologist knows neuromuscular disease but diddly about the machines. The pulmonologist (physician specializing in respiratory problems) knows the machines but not neuromuscular disease.

In our screwed up health care delivery system someone might require that you see a sleep specialist. The sleep guys are used to sleep apneaics who have good lung power and is very unlikely to be familiar with the problems of the neuromuscular patient.

Start with your neurologist. A neurologist who works with ALS patients should certainly be familiar with BiPAP. He may handle your respiratory care himself, but may prefer to refer his patients to a pulmonologist for respiratory care at that point. I would be reasonably comfortable with either of them, but if I were sent to a sleep specialist I would most definitely ask "How many ALS patients on BiPAP have you cared for?" and if he could not demonstrate a very good understanding of ALS, I would be looking elsewhere.

The doctor who handles your respiratory care is going to be a very important person in your care. Patients with ALS who do not want to go on a ventilator most often die of respiratory failure so this doctor will be the one who sees you through to the end or sees you through many years on a ventilator. You may still see other doctors, but odds are that this is the one who will be there directing most of your care. You need someone who is comfortable not only in deciding what pressure settings you need and dealing with any respiratory infection, but also in listening, explaining and helping you make decisions about things like tube feedings, code status, and whether or not to switch to full ventilation when BiPAP is no longer sufficient and perhaps when to discontinue the ventilator. At some point he or she will likely be the physician you depend on to make the end as easy and dignified as possible.

bullet Undergoing Testing

There are several tests doctors can do to monitor how much ALS is affecting breathing:
bullet A respiratory function test involves huffing and puffing into a machine to see how much lung capacity you have. The FVC (Forced Vital Capacity) which is basically how deep a breath you can take is one of the most important findings of the test . At about 70% of normal you begin to notice problems, less than 60% is considered moderate, less than 40% is severe. People with neuromuscular diseases should have the test done while they are lying down as that is when their breathing is the most impaired. A respiratory function test/FVC does not show whether you have sleep apnea or if hypopnea is even worse when you fall asleep, however.
bullet Another helpful test is a simple test of blood oxygen level. This is reported as Oxygen Saturation (O2 Sat) percentage. An O2 Sat of 96% means that 96% of your red bloods cells are carrying a full load of oxygen (are saturated) like they are supposed to be. Normal is 90% or better (usually high 90's). O2 Sat monitoring can be done with a simple little device you clip or tape on your finger tip. No needles! For us, the important thing is to wear the device while lying down and sleeping. A spot check in the middle of the day will no doubt show excellent levels when breathing problems first begin because our breathing is at its worst when lying down and/or sleeping.

To accurately test you, your doctor can arrange for you to use an O2 Sat monitor at home overnight. You just put the device on your finger at bedtime and wear it all night. It monitors oxygen saturation and heart rate, and records it. The next day you return it, the results are retrieved from its memory, and reported to your doctor. If you are breathing too shallowly (hyponea) your O2 Sat should drop. (CO2 levels would be more accurate in spotting hypopnea but as discussed below, they are not as easily done accurately.) If you have apnea, your O2 Sat will drop briefly but dramatically at repeated intervals.


These two tests along with a diagnosis of a neuromuscular disease such as ALS and a description of the problems you are having should be sufficient to get a prescription for BiPAP and insurance reimbursement for it. Unfortunately sometimes it gets more complicated. Physicians and/or insurance companies may want more diagnostic evidence and want other tests done:

bullet ABG's (Arterial Blood Gases)

Doctors tend to be irritatingly fond of these lab tests. ABG's require drawing blood from an artery (usually in the wrist - an "uncomfortable" procedure). ABG's can tell a doctor a lot more about your respiratory status than just oxygen levels. For example, they tell the CO2 levels, can help determine if your breathing problems are due to lung problems or other problems such as liver or kidney disease and even how well your body is able to compensate for the problem. But ABG's are NOT always necessary.

Although ABG's are a perfect way of checking CO2 levels, they are a total waste of time for the early stages of breathing problems in ALS if they are done when you are wide awake and breathing normally! When breathing problems become severe CO2 levels will be high even when you are awake, but not early on when you first could begin benefitting from BiPAP.

DO NOT allow them to draw ABG's during a daytime appointment (unless you have some other lung disease too) as a first step in determining if you need BiPAP. You have to be in pretty bad shape to have a high CO2 while you are wide awake and being stuck in an artery with a big needle! INSIST that the doctor explain what he needs to know from the ABG's that he can't figure out simply by knowing that you have ALS and overnight O2 Sat monitoring. Your doctor may believe that the insurance company will reject a claim for BiPAP without this bit of supportive evidence but I would ask him to file with all the other info he has on you first and would not agree to the test unless the insurance company rejected my claim.

bullet Sleep Study

Some physicians and/or insurance companies will want you to have a sleep study done to verify the need for BiPAP. This expensive test involves spending a night in a sleep lab trying to sleep while you are all wired up with monitoring devices. The information will tell the doctor whether you have sleep apnea and help determine what kind of pressure settings your machine will need. A sleep study is necessary to get a diagnosis of Sleep Apnea, but for an ALS patient that should not be necessary. The use of BiPAP for the breathing problems accompanying ALS is well documented and standard care. Simply having a diagnosis of ALS and evidence of the onset of breathing problems should be sufficient to justify ordering Bi-PAP. A secondary diagnosis of sleep apnea or hypopnea by a sleep lab should not be needed. But, depending on your insurer, you may have to jump through their hoops. Again, your doctor may believe that the insurance company will reject a claim for BiPAP without this bit of supportive evidence but I would ask him to file with all the other info he has on you first and would not agree to the test unless the insurance company insisted on it.

If you are required to have a sleep study, be aware that ABG's are commonly done with them. Again it is important that the blood be drawn while you are asleep -- or as soon after awakening as possible. (No one is going to sleep through an arterial blood draw!) Ideally the blood should be drawn first thing upon awakening. I would refuse to have the test done if it was not done at least before I was out of bed. I have heard of instances where it was done after the patient was up to the bathroom, dressed, and ready to go home! No wonder the ABG's did not support her need for BiPAP! You always have a right to refuse a test or medication, and in this case not only is the test useless but it will work against you in getting reimbursement for BiPAP!!!

Return to top.






How much does BiPAP cost?

The machines cost $2000-$3000. It has been my impression that they are covered by most medical insurances. Although it is possible to purchase your own machine, the most common thing is to "rent" one from a respiratory care company in such a way that you eventually "own" the machine. I have found that renting a machine is well covered but sorting through the finances is a headache. No one seems able to explain it fully. Therapists are seldom well versed in the billing process and billing people only seem to know what your current statement shows, not what is going to be billed in the future. It is also scary because no one seems willing to put anything in writing and rental fees can be $600/month or more! Anyway, the common way of "renting" BiPAP machines is called Capped Rental.

Medicare and most private insurance companies do a "capped rental" on BiPAP machines. As with most durable medical equipment, they will pay 80 percent of the rental fee up for 13 months. Once they have paid that much in rental, the machine is considered paid for and is no longer billed.

In the past, once the 13 months were up you were given the option of owning the machine but not receiving any further visits, maintenance, or repairs from the supplier, OR agreeing that the machine would continue to belong to the supplier and be returned to them if you no longer needed it or changed supplier. With the second option the supplier had a service contract to provide visits by a Respiratory Therapist to check the machine or adjust the settings or help you find the mask that works best for you. Maintenance, repairs and replacement were the responsibility of the supplier at no charge to you.

In 2006 Medicare dropped the second option by placing BiPAP in the category of medical equipment that does not need frequent or substantial servicing. Now, after 13 months the machine belongs to you and the supplier has no service contract and provides no further services.

The machine is expected to last for at least 5 years and Medicare will pay for any needed repairs, but the routine maintenance is up to you, as is dealing with mask problems and setting changes. The loss of regular contact with a Respiratory Therapist who works closely with many BiPAP users leaves users without a valuable resource.

Replacement of masks, tubing, etc. is 80% covered by Medicare on their time schedule: 90 days on masks, 2 pair of nasal pillows and new tubing per month, 180 days on headgear.

There are no doubt variations from one insurance company to another, but it is likely that insurers will follow Medicare's lead and end their service contracts with BiPAP suppliers.