Post-Polio Health (ISSN 1066-5331)
Vol. 17, No. 2, Spring 2001
Additional thoughts from Peter C. Gay, MD
Associate Professor, Critical Care and Sleep Medicine, Mayo Graduate School of Medicine, Rochester, Minnesota
On weakness ... "The vernacular defining post-polio syndrome includes non-specific weakness. Many physicians overlook the fact that polio survivors are describing respiratory problems."
On symptoms ... "The important thing to recognize is that the vast number of polio survivors do not necessarily have lung disease, per se. The problem usually is the inadequate way they move air in and out of their lungs.
"It is important to determine which symptoms are related to breathing, which are related to the heart, and which are related to deconditioning. Even Olympic athletes can become deconditioned."
On abdominal paradox ... "Many polio survivors have difficulty with breathing while lying. Physicians can assess this by observing the abdominal paradox which occurs when the abdomen inappropriately collapses inward as the chest expands during inhalation.
"Normally when one lies down and takes a deep breath, the diaphragm pushes down and the abdomen pushes outward. If the diaphragm is very weak and the chest muscles are doing most of the work, then the abdomen is going to paradoxically collapse. This is a very specific sign that a physician can recognize by placing a hand on the abdomen and asking the patient to take a deep breath. If the abdomen collapses during inspiration, it is a sign of a weak diaphragm. During sleep, this is critical to understand."
On deterioration of quality of sleep ... "The sleepier that people get, the more they want to sleep, and the more they are tortured by the need to wake up to breathe."
On sleep apnea ... "The 'I won't breathe' form is central sleep apnea. The controller, during REM sleep particularly, stops firing impulses adequate to make one breathe. It is important to demonstrate the difference between these because different equipment is needed for each form.
"The 'I can't breathe because the upper airway is blocked' form is obstructive sleep apnea. It is most common in males and is due to being overweight and to the size of the neck and structure of the upper airway. In post-polio patients, the weakness of the muscles of the mouth can be such that, when lying on one's back, the muscles can block off and cause snoring."
On nighttime assisted ventilation ... "Breathing at night is like driving. You need power steering. You still want to drive, but it feels like you are driving a big Mack truck. You need a device that allows you to turn that steering wheel more easily."
On using oxygen ... "In normal sleep, sensitivity to CO2 is reduced so that we all shallow breathe during REM sleep. Elevated CO2 during REM sleep lets people stop breathing or slow breathe until the oxygen saturation levels get so low that the brain alarms to say, 'Wake up!' From that standpoint, supplemental oxygen tends to be a poison to people with this problem who are not also getting ventilation at the same time, because they lose the low O2 wakeup alarm."