The Motor Act of Breathing

is key to the gas exchange of lungs and of cells, including neurons, Breathing uses chemical and mechanical processes to bring oxygen to every cell of the body and to get rid of carbon dioxide. Our body needs oxygen to obtain energy to fuel all our living processes. Nursing Times 2018. Yet it is endogenous carbon dioxide that is tracked carefully but the brain not oxygen.

Too much C02 [above what is needed] produces many effects on the body, depending on the excess amount in the blood and in the different types of cells. These effects can include systemic hypertension, increased heart rates, headache, confusion, mild narcosis, and shortness of breath [which may or may not be visible]. https://en.wikipedia.org/wiki/Hypercapnia

The cause of hypercapnia may be due to excess C02 in the air [especially indoor air – when there is not enough exchange of air for the number of people or when combustion gases build up inside and it is not properly vented.Combustion Gases in Your Home [or school or workplace] – Things You Should Know About Combustion Spillage https://www.nrcan.gc.ca/energy-efficiency/homes/combustion-gases-your-home-things-you-should-know-about-combustion-spillage/18639.

Causes of hypercapnia can also be a result of illness [eg infection] and any condition which makes your skeletal muscles weak; not just making you feel tired and making your legs and arms feel weak, but weakness affecting your skeletal muscles in your chest which push air in and out of your lungs.

Blood flow is also important to the exchange of air in the interior of your cells. Blood needs to flow to cells in order to bring oxygen to the mitochondria to produce ATP, the energy currency of cells. Producing this energy produces Carbon Dioxide continually. Much but not all of the C02 needs to diffuse out of the cell and into the blood and the excess is exhaled into the atmosphere.

Thus certain conditions which limit blood flow, such as heart failure for example, can also cause a buildup of C02 in the cell. [if I understood correctly].

Hypercapnia may happen in the context of an underlying health condition, and symptoms may relate to this condition or directly to the hypercapnia. Specific symptoms attributable to early hypercapnia are dyspnea (breathlessness), headache, confusion and lethargy. Clinical signs include flushed skin, full pulse(bounding pulse), rapid breathing, premature heart beats, muscle twitches, and hand flaps (asterixis). The risk of dangerous irregularities of the heart beat is increased. https://en.wikipedia.org/wiki/Hypercapnia

Hypercapnia is hard to detect without a specific test called an arterial blood gas test, which is not usually given to patients who are able to walk about; they are reserved for the critical ill patient in the intensive care unit.

Consequently we know very little about hypercapnia in adults with worrisome nonspecific physical signs and symptoms such as essential hypertension, persistent fatigue, heart failure, persistent delirium, or any motor states with psychomotor retardation or excitement.

The motor act of breathing is often disturbed in hypercapnia. Resting baseline breathing rates may be too slow or too fast or even irregular with apneas. You might think that doctors would make sure to carefully count the baseline respiratory rate at rest [which is involuntary] and linked to the state of the brain, peripheral muscles, peripheral nerve fibres and the partial pressure of C02 of the blood which is kept within a narrow range in order for enzymes and proteins to work properly in the running of the body. But doctors do not usually measure baseline resting breathing rates. They do not carefully look for accessory muscle use which suggests laboured breathing. They do not know if breathing rate and/or responses to rising C02 changes in adults over time.

Normal respiration rates for an adult person at rest range from 12 to 16 breaths per minute.
Vital Signs (Body Temperature, Pulse Rate, Respiration Rate …https://www.hopkinsmedicine.org › conditions-and-diseases.

Unless a person complains of breathing difficulty or is visibly or audibly having trouble breathing, normal respiratory rates are assumed. Yet baseline resting breathing rates are handled by the autonomic nervous system and are involuntary and are often not noticed by the patient.

Paula has very abnormal motor control of breathing. Paula is not very aware of this. Paula uses accessory muscles to inhale and to exhale. Paula is not very aware of this. Paula looks like she is breathing normally, despite a very depressed breathing rate of 3 [deep] breaths per minute with active exhalation [active exhalation points to laboured breathing]. Paula does not look like she has laboured breathing. But she does. It takes a lot of extra effort for Paula to exchange normal or near normal amounts of air compared to someone with a more normal respiratory rate. Yet she does not know this. And her doctor assumes she has normal motor control of breathing, because she looks so normal. The truth is that doctors cannot tell anything about problems with the motor control of breathing because they have not studied this very much.

Early physiology pioneers found a wide range of respiratory rates in healthy adults; respiratory rates as low as 3 breathes per minute to respiratory rates as high as 30 breathes per minute.

Why would this be when we know that 12 to 16 breathes is most likely the easiest in terms of effort of the respiratory muscles and the most efficient interns of reducing dead space.

Why such a large range? And at what cost metabolically ? Especially in high C02 atmospheres or during illness and infection, sapping one’s strength and affecting the throat and the lungs.

Why have a baseline resting respiratory rate that is depressed or too fast? Why the need for accessory muscles? What is the effect on reacting quickly to carbon dioxide build-up in the blood and cells? Can a person with motor control of breathing issues adapt during illness? What if perfusion is poor, how does that affect oxygen/C02 exchange n the periphery? What if perfusion is abnormal due to cerebral vasodilation, due to C02 buildup, what are the effects then?

Hypoventilation is breathing that is too shallow or too slow to meet the needs of the body. If a person hypoventilates, the body’s carbon dioxide level rises. This causes a buildup of acid and too little oxygen in the blood. .Jan. 16, 2021
Hypoventilation: MedlinePlus Medical Encyclopedia

Paula has hypoventilation as her baseline resting respiration. Did she always have it? No one knows. She doesn’t know. She does not feel hypoventilation and her hypoventilation is not at all visible.

Could her baseline resting respiratory rate have dropped [due to illness or injury] leading her to become ill and most likely hypercapnic all those years ago?

No one knows what her respiratory rate was before her illness; it may have been higher than 3 breaths per minute. Her respiratory rate has been 3 breathes per minute ever since that attack [when she and I began to measure it frequently].

The motor control of breathing can be explored through the study of respiratory rate in the various stages of adulthood. The motor control of breathing is complex yet easy to measure, by measuring baseline rate and tidal volume and minute ventilation, and if called for, by measuring PCO2 with serial arterial blood gases, especially if the patient is unwell and not themselves and experiencing adult “failure to thrive” due to hypercapnia.

Treatments exist and more treatments can be discovered….lucky for Paula and others, the effects of hypercapnia are completely reversible…unless the dose is such that you die of it.[it is an asphyxiant at high doses].

I think that there is a lot of exciting work ahead so we can answer some of these questions and possible cure patients of this reversible dementia or insanity.