You have to have a physician's order (prescription) to get a BiPAP/AVAP machine even if you
do not plan to seek insurance reimbursement so the first step is:
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 may be
unfamiliar with the problems of the neuromuscular patient.
Start with your neurologist. A neurologist who works with ALS patients should certainly
be familiar with NIV. 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/AVAP 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/AVAP 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.
Undergoing Testing
There are several tests doctors can do to monitor how much ALS is affecting breathing:
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.
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 blood 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 fingertip. 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 a recording 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 (hypopnea) 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/AVAP 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.
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 benefiting from NIV.
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 NIV. 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/AVAP 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.
Sleep Study Some physicians and/or insurance companies will want you to
have a sleep study done to verify the need for NIV. 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/AVAP 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/AVAP 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 NIV! 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 NIV!!!
