Assistive Devices for Breathing
The breath that you breathe in contains oxygen. This breath is often called an inhalation. The breath that you breathe out contains carbon dioxide. This breath is called an exhalation.
During sleep, your breathing naturally becomes more shallow. If your breathing becomes so shallow that you are unable to get adequate oxygen in, or carbon dioxide out, this is called hypoventilation (“hypo” means too little, and “ventilation” means breathing). If you are experiencing hypoventilation during sleep (at night), it is referred to as nocturnal hypoventilation.
Breathing during sleep can also be obstructed, meaning that there is something blocking your airway that keeps oxygen from coming in and carbon dioxide from going out. Often people with obstructed airways snore during sleep. Sleeping with an obstructed airway may make you have short episodes of not breathing. This condition is call obstructive sleep apnea. Waking up with headaches, feeling tired or sleepy, and not being able to pay attention may also be signs of obstructive sleep apnea. This can be common in people living with Duchenne, especially those who have gained weight as a result of steroid use.
CPAP vs. BiPAP
The differences between C-PAP (continuous airway pressure) and Bi-PAP (bi-level airway pressure), two methods of assisting nighttime breathing, can be confusing. This video explains the difference between the two and when each should be considered/used.
CPAP stands for “continuous positive airway pressure.” A CPAP machine delivers a constant inhalation (breathing in) pressure and exhalation (breathing out) pressure. This constant pressure keeps the airway open between breaths, and is a perfect tool for a person who has obstructive sleep apnea. If a CPAP machine is recommended for you, be sure to get a machine that can later be converted to a BiPAP machine, which you will need when you are older.
A bilevel positive airway pressure, or BiPAP, machine, delivers two different pressures: a higher pressure during inhalation to help push air in, and a lower pressure during exhalation to help air breathe out. For patients with Duchenne, who have weakened respiratory muscles and who have sleep hypoventilation (not obstructive sleep apnea), BiPAP is needed. If you are seen in the emergency room for respiratory distress, respiratory assistance should be provided by using BiPAP.
A FVC (forced vital capacity) <30% is an indication that a sleep study is needed and is usually an indication of the a need for nighttime breathing assistance. Morning headaches, frequent waking during the night, poor daytime attention/performance, or high levels of carbon dioxide (CO2) on a sleep study may indicate that nighttime breathing assistance may be helpful.
Video: Nighttime Breathing
Monitoring your breathing during sleep is important. While you sleep, your body breathes oxygen in and carbon dioxide out. If your body is not getting enough oxygen, or has too much carbon dioxide, you won’t feel your best while you are awake.
Assistance for Nocturnal Hypoventilation (BiPAP): early non-ambulatory
Signs that breathing assistance during sleep may be needed include restless sleep, frequent awakening and requests for repositioning, nightmares, sweating, morning headaches, a need for daytime naps, mood changes, and school performance changes in older students (high school, college).
Bilevel positive pressure ventilation (BiPAP) provides breathing support for the management of nocturnal hypoventilation. As stated above, BiPAP assists breathing using two pressures: an inspiratory pressure (breathing in, higher pressure) and an expiratory pressure (breathing out; lower pressure that keeps airways open between breaths). A “back up rate” causes the machine starts a breath if breaths are not occurring frequent enough — this is important.
BiPAP can be used with many different interfaces, or masks. These can include a mask only over the mouth, a mask only over the nose, or a mask that covers both. Interfaces come in many shapes and sizes. You many need to try 2-3 different interfaces to find one that is comfortable and works for you.
Once you are using the BiPAP, the setting will need to be monitored to make sure that you are getting breaths delivered using the right pressures. Repeated sleep studies may be needed to adjust the BiPAP settings.
Daytime assisted ventilation (late non-ambulatory)
A FVC 15-20% predicted, or a carbon dioxide level >45 mmHg while awake may be an indication that you are not getting enough oxygen while you are awake.
If breathing assistance during the day is needed, tracheostomy and oxygen should not be first responses. BiPAP, provided by a “sip vent” (a small mouthpiece connected to the BiPAP that can be sipped when additional breaths are needed) is often sufficient to provide breathing assistance while awake.
Signs that daytime assisted ventilation may be needed can include feeling shortness of breath, anxious, soft voice, or needing to breathe during even short sentences.