Hypercapnia, Minute Ventilation, Neurological Nonspecific Signs

I have finally figured out what I think should be researched in the study of neurological and neuropsychiatric conditions including delirium and dementia.  I think my research is done!

I am concerned that different stages of hypercapnic respiratory failure are underdiagnosed in many patients.  


In Canada, minute ventilation is never measured,  in ambulatory confused, demented or depressed, manic, psychotic or confused, or even comatose patients or those with akinetic mutism. 

My friend Paula has  decreased minute ventilation. She exchanges 1.5 L of air per minute at rest when sitting quietly instead of the normal 6 to 8 L at rest.   Her tidal volume is .5 L and her respiratory rate at rest is 3 breaths per minute.  She is perfectly fine and healthy and fit. She feels normal. She looks normal, no one can tell.

I recently read StatPearl , about  CO2 Narcosis and found out that minute ventilation is a very important factor in diagnosing this.  I also found out that this condition is reversible and has many different causes.   https://www.ncbi.nlm.nih.gov/books/NBK551620/          StatPearls     Carbon Dioxide Narcosis    Michael Drechsler; Jason Morris.      Author InformationLast Update: March 20, 2020.

Scientists like JS Haldane found out that the range of breathing rates in the normal healthy adult population could range from as low as 3 breaths per minute [like Paula]  to as high as 30 [like her nephew] . But you had to count it to know.  So I know that there are other [hidden] Paula’s in the world.  Paula was resuscitated and transfused at birth and thrived from then on. 

Maybe she had evolutionary conserved epigenetic changes as a result of her exposure to anoxia and then hyperoxia    [in 1955 they used high levels of oxygen]    and foreign blood products.    Who knows?   Anyway it mostly worked!  She was fine for most of her life.

I think that people at the extremes of the ventilation range must be at a greater risk for attacks of hypercapnia, with or without normal lung function. Paula had an episode of what she now thinks was “mild akinetic mutism” with cognitive impairment and inhibited speed and movement. It lasted a year and a half.  It lifted spontaneously.  She was misdiagnosed with depression and given psychotherapy.  Psychotherapy does not work when you have even a mild attack of akinetic mutism.

We now think that Paula had an attack of altered mental status caused by  a stable level of  hypercapnia.   Hypercapnia might sometimes present as nonspecific neurological signs and symptoms, we think.  Arterial blood gas analysis of PCO2 would explain the signs and symptoms on all systems of the body.

We are now toying with the idea that mild hypercapnia is the reason for Human Beings higher function of MIND and brain function.  Maybe the slower breathing rates of humans [vis a vis the other animals] explains why our minds work the way they do.  Interesting idea, I think.

We wish to convince doctors to research the possibility of  different levels of hypercapnia in patients with impaired function , from those in coma states to heart failure patients to COPD patients  to the study of delirium and dementia and particularly in manic depressive patients. 

Dr Emile Kraepelin found abnormal breathing rates in thousands of his manic depressive patients- too slow in depressive insanity and too fast, periodic breathing in the same patients during manic insanity. 

Insanity was Kraepelin’s word for extended delirium [all motor subtypes] resulting in impaired cognition, dysphoria, euphoria, delusions, hallucinations and catatonic states and psychosis- all of which, I think , can be induced by different and shifting levels of hypercapnia.

Please discuss this with your colleagues.

We think someone should do research on altered mental status and hypercapnia using measurements of minute ventilation on different patient groups.


What do you think?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s