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“Carbon dioxide is the basic
nutrition of every life form of earth. 

It acts as the main regulator of all functions in the organism; it is the main internal environment of the organism; it is the
vitamin of all vitamins.”

K.P. Buteyko 


Professor Buteyko's basic introduction of his method, in his own words. 

Although focused on diabetes, this extraordinary lecture, goes deeply into many factes of the method. 

Taken from the above article, it strips down the ambiguity of the "stressed" condition and explains the phenomenon with exceptional clarity. 

In an attempt to stem the diltuion and ineffective use of his method, Professor Buteyko provides the guidlelines for its proper administration. 

An informative and practical article on the basics and practicalities of learning Buteyko's Method. 

An extraodinary academic article around the history and technical aspects of Carbon Dioxide that explains the authenticty, common misapprehensions and other interesting details.  

Biochemical analysis of Buteyko's Method by Karzimov

For those with a highly technical interest, this biochemical analysis of Buteyko's Method by Karzimov is both an extraordinary piece of technical work  as well as being a highly detailed explanation of mechanisms around how and why the method works. To access, please press the pdf. link. 

Buteyko Australia, Queensland Asthma Foundation – Effect of Buteyko in the management of asthma.

These are the published details of a double randomized controlled trial, conducted in Australia under the auspices of the Queensland Asthma Foundation, prompted by the media. It is an interesting study in which by all parameters, Buteyko achieved the best results in recorded medical literature for the reversal of asthma symptoms. But it did not impact the so called objective testing for asthma and thus left the academics confused.  



Thirty-seven years passed since I managed to discover the cause of the so called "diseases of civilisation" (broncho and vascular spasms, allergy, etc.) The only cause of them is alveoli hyperventilation, or deep breathing. The idea which came to my mind was that by decreasing the depth of breathing, or in other words, by the normalisation of the breathing we could cure that range of illne sses. The idea was based on fundamental laws of physiology, biochemistry, biology and so on, and the correctness of that assumption was confirmed by experiments and tests. 


The main postulates of my theory are:


1. It is known that while breathing deeply the organism exhales too much CO2 and therefore its content in lungs, blood and cells decreases. The lack of CO2  caused by deep breathing changes blood pH toward the alkaline direction.

Such a change of blood pH badly influences the activities of all enzymes (there are about 1000) and vitamins (there are about 20). As a result, the whole metabolism suffers. And, when blood pH is reaching 8, the metabolism becomes improper to the extent that the organism dies.


2. It is also known that the lack of CO2 leads to spasms of bronchial smooth muscles, brain vessels, heart, intestines, gall ducts and other organs. 


At the end of the 19th century the Russian scientist Mr. Verigo from the town of Perm discovered a seemingly weird law. According to him, as a result of a fall Of CO2 in blood the bond between oxygen and haemoglobin becomes stronger. This creates difficulties in the oxygen transition from blood to brain cells, heart, kidney and other organs. In other words, the deeper the breathing, the less oxygen is available for the brain, heart and kidney cells. This particular law, not very well known so far, underlies our discovery. As the Verigo law was left under wraps, the same discovery was much later made by a Danish scientist and named the Bohr Law. Being unfamiliar with this law will result in great difficulties in understanding and accepting the theory offered by us.


3. The lack of oxygen in the brain (hypoxia), caused by the deep breathing, is aggravated by broncho and angiospasms - the organism's attempts to compensate for hypoxia of vital organs - and results in high blood pressure (arterial hypertension).Consequently, the blood flow increases and blood supply to the organs improves.

Along with the lung hyperventilation, the hypoxia creates a false feeling of lack of air, accompanied by intensified breathing. This leads to an inevitable progression of the disease of CO2 deficiency in nerve cells, stimulating the whole nervous system, and this makes the organism breathe even deeper. Thereby, the nerve cell hypoxia, along with upset metabolism and over-excitement of the nervous system, causes weakness of the intellect and destroys the nervous system (brain vessel sclerosis). And that finally leads to a mentality dysfunction.


4. Destruction produced by deep breathing is aggravated by poisoning of the environment and food with chemicals, herbicides and medications. If it is so, then all of Western medicine's main principles are based on methods of prevention and treatment, consisting of teaching people deep breathing techniques, that only assists in creating those diseases. At the same time, deep breathing exercises and broncho-vasodilatory medications that increase the rate of CO2 removal from the body do not improve but worsen the state of already ill patients. That is why the so called "diseases of  civilization" are not yielding to treatment but spreading even further. The discovery of the fact that deep breathing is the main cause of those illnesses allows us to prove scientifically and experimentally that existing principles and methods of treatment are faulty.

The hyperventilation test, offered by us, represents incontestable evidence of the correctness of our discovery. The idea of the test is to ask a patient to deepen the breath and check how the widespread recommendation "Breath deeper!" affects that person. In a few seconds or minutes the hyperventilation test provokes or intensifies symptoms while the lessening of the depth of breathing quickly stops them. This means that the only scientifically explained principle for prevention and treatment of the illnesses of the century is a decrease of the depth of breathing in order to normalise its physiological function.


Based on this idea, the method of the intentional normalisation of breathing, or in other words, the deliberate volitional breathing method (DVBM) was developed. 


The principle is based on decreasing the depth of breathing by deliberate efforts made by the patient to relax respiratory muscles until the feeling of some shortage of air. All mentally sound adults and children from the age of three are able to learn the method. Our ideas can be used on a broader scale ‑ starting from antenatal training of prospective mothers, caring for infants, teaching children some physiological norms and finishing by the implementation of the general health improvement program for the entire population. The ideas also can be used widely in space medicine, surgical practice (as a part of the preparation to complex surgeries), pedagogy, singers' training and sport. 

In common opinion, medicine (similar to many other  sciences) needs to be radically reshaped. We are seeing our ideas ‑ along with other progressive but previously rejected ideas as a foundation of future medicine.


We believe the first and foremost task is to give people the information about our discovery in order to stop the deep breathing propaganda by radio, TV and mass media and to cancel deep breathing exercises at the hospitals and clinics.

The complete victory will come when the whole civilised world realises: the deep breathing principle of greed is the worst of human vices. That it is the source of almost all troubles, the main cause of diseases and death for the overwhelming majority of human beings. 


K.P. Buteyko

To the theory

To the theory of diabetes mellitus pathogenesis & basic principles of hormonotherapy. 


Science consultant, Institute of Clinical Experimental Medicine,  

Siberian branch, Academy of Medical Science, USSR



My theory of the diabetes mellitus pathogenesis was firstly published in the "Inventor and Efficiency Expert" magazine, 1962, #5. Strictly speaking, in that article the whole theory of deep breathing was presented and you should learn and pass to your patients its basic clauses.


 The theory of the deep breathing disease is based on the principles of physiology. However, our opponents holding higher positions in our medicine are still not able to grasp the fundamental idea stating that the deep breathing causes hypoxia. Let me get back to (laws, which underlie the theory) the deep breathing disease. 


 1. Hyperventilation, or deep breathing, does not add oxygen to arterial blood. Under normal breathing the blood contains maximum amount of O2 (normoxia) and simply not able to absorb more. 


It is known that regardless of how long one will breathe pure oxygen, the level of oxygen in their haemoglobin increases insignificantly. at 1 - 1.5% only. With that the O2 partial pressure in plasma increases and bronchi and vessels spasms occur. That is why pure oxygen supply to the patients suffering from asthma and vessel pathology causes the increase of hypoxia. Thus to inhale more pure oxygen means to pump O2 into an organism without taking into consideration the mechanism of hypoxia. 


2. Hyperventilation does not intensify metabolism. In other words, the organism is nor a furnace: the more one blows into it, the better it works. On the contrary, The deeper and more intensely the organism breathes, the less oxygen goes into blood. As a result, hypoxia develops, metabolism products become underoxidised. That is the way our body works. Next, the metabolism deteriorates, blood pH increases in the alkaline direction and the blood itself begins to accumulate underoxidised products. This is how metabolic acidosis occurs. 


1st stage of hyperventilation is respiratory, or gaseous, alkalosis caused by CO2 deficiency. 2nd stage is the development of metabolic acidosis. It is caused by the accumulation of underoxidised products, which happens due to hypoxia and represents a compensatory reaction against gaseous alkalosis. Our opponents are still not able to understand the reason for deep breathing of asthmatics to comprehend what was studied and explained by us a long time ago. Confusion about the acid-alkaline balance continues. But we have sorted it out; such patients have got both gaseous alkalosis and metabolic acidosis. They compensate each other (a dynamic process for a short period of time). However, both gaseous alkalosis and metabolic acidosis can be liquidated by normalising the breath. 


While reducing the depth of breathing some oxidising occurs due to gaseous acidosis. When lactic and pyruvic acids along with other underoxidised products get oxidised, non-gaseous metabolic acidosis decreases. That means everything goes back to normal with a normalisation of a breath. However, we have the impression that nobody looked into the matter except us. 


3rd stage: in consequence of changes caused by 1st and 2nd laws, all enzymes and vitamins activities become erratic. That leads to destruction of all types of metabolism. Consequently, diabetes mellitus develops. So, diabetes mellitus is nothing else but a destruction of carbohydrate metabolism. Thereby, I offer the theory that diabetes mellitus is caused by CO2 deficiency. 


CO2 deficiency is causing the whole range of metabolism destruction at all levels of the organism up to the cell level. What is happening during those processes? All body organs and systems are getting depressed. I consider that deep breathing is a body stress. 


Any stress, whichever you are going through, inevitably leads to deepening of breath. That is an ancient body reaction. Its role is to avoid CO2 deficiency in the organism. The point is that in cases of positive or negative emotions, an intensive CO2 exhalation from the body occurs. 


As a result, the central nervous system becomes over reactive and the breathing deepens. Because of deep breathing the oxygen content in lungs slightly increases. Finally a strong tension develops, which is necessary to mobilise physical strength to attend the stress - in the form of fighting, attacking, defending, fleeing, etc. We have to view the increase in CO2 exhaling, the boost of energy and the intensification of metabolism as compensatory factors. That is why any emotion must be discharged physically. That is our point of view. I.P. Pavlov failed to explain why undischarged emotions are so bad for the organism. We did it. 


I want to emphasise once again that we consider deep breathing to be a stress. It means that during stressful situations, in order to eliminate stress, one has to lessen his depth of breathing, in other words, to use our method and by doing that to calm the nervous system down. 


During a stress some psychotropic substances - such as adrenaline noradrenaline and others -are produced. They stimulate our defence and attack reactions, enhance our muscle strength, and so on. At the same time the production of insulin goes down and its concentration in blood drops. Deep breathing causes some body reactions leading to the increase of sugar content in blood, which helps the body cope with the energy upsurge. The increase of blood sugar is useful when there is enough insulin in the body because it enhances the gaseous substances flow into muscles, brain and cells and consequently normalises their functions. However, if deep breathing lasts longer, the compensatory mechanism turns into a pathological one as with time an insulin deficiency develops. Together with CO2 deficiency it leads to all kinds of metabolism destruction. For example, due to stress and deep breathing, arthritis patients have got increased cholesterol content. We have confirmed by experiments that by decreasing the depth of breathing the cholesterol content in blood returns to normal. 


Coming back to diabetes, it is important to stress that the deep breathing leads to increasing production of some substances such as glucagon which assist in increasing blood sugar content. The Krebs cycle changes direction, other chemical processes also alter aiming to reduce sugar decomposition and to increase its concentration in blood. The whole system of biochemical reactions comes to work in order to increase blood sugar content. That is why hyperglycaemia along with insulin deficiency should be viewed as a defence reaction against energy deficiency. 


So far Western medicine believes that nature is stupid and one can interfere and recast it with impunity. Now you have learnt why nature is doing certain things and how sensibly we have to act towards it. We consider bronchospasm, vessel spasming, high blood pressure and other body reactions to be useful defence mechanisms to compensate to some defects of the organism. Exactly from that point of view we analyse hypoglycaemia. Now you understand that apart from insulin deficiency, a number of other processes also increase blood sugar content. Hence, the conclusion: one can't estimate insulin concentration in blood by looking at the sugar level although coincidentally they can agree. We are convinced that the increase of sugar level is not a pathologically damaging factor. Sometimes we observe a tenfold rise of blood sugar, and so what? Nobody died from such a hyperglycaemia. Sugar is not poisonous. That is clear for everybody. 


In common practice the main criteria for choosing the insulin dosage is the sugar level. In leading Moscow clinics, insulin doses are regulated by blood sugar in spite of the fact that it is absurd and a great mistake. To define an insulin dose we need to find some true evaluating criteria for insulin deficiency. This is a very difficult task. In this respect, it appears to be necessary to define the principles of hormone replacement therapy. Working on the task we were acting in accordance with the fundamental laws of nature as applied to the human body. 


How does the Western medicine act? It is based on blind empiricism It will stop short of nothing in order to find the way to conquer the illnesses which can be cured by our method. They use the most elaborate methods and medications with no avail! 


However, to eliminate diabetes mellitus pathogenic factors, it was necessary to find what was causing the insulin deficiency, and to remove that cause and consequently the hormone deficiency itself. 


The following are the fundamental principles of the hormomotherapy, which we adhere to and which are usually broken or not recognised by the existing medical practice. The main principle is as follows: if there is some hormone deficiency in the body, one has to define its cause and eliminate it. 


We believe the main cause of hormone deficiency illnesses is deep breathing, Why? The deep breathing upsets metabolism in those systems, which are responsible for proper regulation of the activity of hormone systems such as hypothalamus and pituitary gland. 


CO2 deficiency caused by deep breathing leads to: biosynthesis disturbances with respect to amino acids, purines, pyrimidines, fatty acids and carbohydrates; oxystructure stabilisation (Verigo-Bohr reaction moves left);  discharge of cell transmembrane potential; depletion of blood plasma buffer system;  pH alteration in blood plasma and cells.


Consequently, the following effects occur: biosynthesis disturbances with respect to proteins as well as enzymes, antibodies, nucleic acids, lipids and polysaccharides; tissue oxygen deprivation; changes in cell stimulation and interaction patterns; change in enzyme activity and decrease in antibody-antigen affinity. 'Rat manifests itself in the form of disorders of cardiovascular, humeral, immune, hormone, digestive and nervous systems. As a result, metabolism in hormone cells also gets upset. 


In accordance to our data, deep breathing people have always got practically all kinds of hormone deficiency. Even their sexual hormones, especially female hormones, are low. Obviously, not only deep breathing could cause hormone deficiency. But, in any case, the deep breathing always aggravates the process, example, under the radiation the sexual organs suffer more severely and hormone secretion decreases. If that is happening in combination with the deep breathing, pathologic changes in the body grow bigger and faster. 


Patients with some upset hormone functions, especially those with diabetes, show clearly noticeable hyperventilation. Our data shows that the control pause produced by diabetes sufferers is 5-10, maximum 15 seconds. Correlated with those figures CO2 level is equal approximately to 32-34 mm of mercury, which means it is twice lower than normal. That allows me once again to declare the main cause diabetes mellitus is CO2 deficiency caused by deep breathing. If the diabetes patient has got both deep breathing and CO2 deficiency our theory can explain pathologic changes in their body. 

As it is known, the majority of diabetes patients develop arteriosclerosis resulting in heart attack, stroke, thrombophlebitis complicated with gangrene, etc. The correlation between those diseases and deep breathing is proven by scientific research. 


What is our medical tactic? We believe first of all it is necessary to use the hormone replacement therapy, i.e. to give patient hormones as much as the shortage of it occurs in his body. The question is the quantity: to overdose or under dose?

That one is an important and significant question. With respect to it, medicine has reached a deadlock and it is common to overdose hormones. How such doses affect the organism? They affect it in a way when the functions of one another hormone producing organs become lowered and suppressed, and then down line - if hormone medication intake continues to increase - the hormone producing organs can become fully disabled. Moreover, ideal hormone medications are not available yet. A hormone extracted from one individual contains different antigens to that one extracted from another. An introduced hormone will always be worse than that produced by the body. Obviously, the introduced hormone is more harmful than ours. And what if we do overdose it? 


So what is the best solution for the situation? 


1. We suggest to completely turn down those existing dangerous schemes of treatment based on hormone overdose. 


2. We suggest defining hormone dosage using three parameters: a pulse, control pause and general feeling of well being. The hormone dosage should be changed daily, again - in accordance to a pulse, control pause and the general feeling of well being. 


The daily dosage may be increased or decreased by 25% or even 50%. The base daily dosage is the dosage when the patient feels well and when asthma attacks (for example) can be stopped easily with a use of an inhalator or our method.  


The detailed instructions on hormone therapy are enclosed as an attachment to DVBM instructions. We wish to emphasise that the hormone therapy tactics offered by us can be very effective only in conjunction with DVBM. Only under this condition the gradual decrease of hormone dosage along with the adrenal gland tissue restoration becomes possible. Accordingly to our data, those patients who increased their control pause up to 30-40 seconds, with a pulse rate of 65-70 beat/min., have stopped taking hormone medications because they did not need them any more. Naturally, we have arrived at the following conclusion: it is compulsory to drastically alter the existing approach to the hormone therapy, to make it coherent with the scientific data which have been offered to your attention at the current conference.  

The Mechanism of Stress.

The mechanism

Any stress that you are going through inevitably leads to a deepening of the breathing. This is an ancient bodily reaction. Its role is to avoid CO2 deficiency in the organism. The point is that in cases of positive or negative emotions, an intensive CO2 exhalation from the body occurs. As a result, the central nervous system becomes over reactive and the breathing deepens. 

Because of deep breathing the oxygen content in lungs slightly increases. Finally a strong tension develops which is necessary to mobilize physical strength to attend the stress - in the form of fighting attacking, defending or fleeing, etc.


We have to view the increase in CO2 exhaling, the boost of energy and the intensification of metabolism as compensatory factors. That is why any emotion must be discharged physically. That is our point of view. I.P Pavlov failed to explain why undischarged emotions are so bad for the organism. We did it. 


I want to emphasize once again that we consider deep breathing stressful. It means that during stressful situations, in order to eliminate stress, one has to lessen the depth of breathing, in other words, to use our method and by doing that, calm the nervous system down.  


During stress some psychotropic substances - such as adrenaline, noradrenalin and others are produced. They sstimulate our defence and attack reactions, enhance our muscular strength, and so on.

At the same time, the production of insulin goes down and its concentration in the blood drops. Deep breathing causes some reactions leading to the increase of sugar content in blood which helps the body to cope with the energy upsurge. The increase of blood sugar is useful when there is enough insulin in the body because it enhances the gaseous flow into muscles, brain and cells and consequently normalizes their function. 


However, if the deep breathing lasts longer, the compensatory mechanisms turn into pathological ones and in time, an insulin deficiency develops. For example, due to stress and deep breathing, arthritis patients have increased cholesterol content. We have confirmed by experiments that by decreasing the depth of breathing the cholesterol content in blood returns to normal. 


Taken from Part 1 of : To the theory of diabetes mellitus pathogenesis - Basic principles of hormonotherapy by K.P. Buteyko PhD., Science Consultant, the Institute of Clinical Experimental Medicine, the Siberian branch of the Academy of Science, U.S.S.R.


Professor Buteyko's statement concerning the administration of his method. 

I, Professor Konstantin Buteyko, the inventor of the method of treatment for some chronic diseases of the respiratory system, nervous system, hormonal system, cardio-vascular system, immune system (Patent No: 1067640), known in the West as the Buteyko Method, categorically make this statement:


The Buteyko Method appears misleadingly simple to practice. However, there is a specific training on how to apply this method to each individual patient. If this is done incorrectly there could be severe complications and damaging effects on a patient’s health.

It is for this reason that I only allow qualified practitioners to teach the Buteyko Method to patients in a workshop environment. As a Professor of Medicine I clearly state that it is dangerous for medical doctors or health care professionals to practice the Buteyko Method without the appropriate training.


I categorically state that it is exceedingly dangerous for patients to be instructed in the Buteyko Method through the medium of video, audio tapes, books, instructions and manuals. The Buteyko Practitioner assesses the 4 page Patient History Form before commencement of the workshop. They then monitor the progress of each individual patient on a daily basis during the workshop course, adjusting the use of the techniques to each individual’s need, to ensure correct use of the method and prevent complications arising. They are available for follow-up consultations where necessary.


Any Buteyko practitioner who does not train patients thoroughly in the Buteyko Method by taking shortcuts with videos, tapes, books, instructions and manuals and who try to offer training to potential Buteyko practitioners will have their certificates removed.


I will also use legal measures and public opinion to stop those who misuse and abuse my method and bring the Buteyko Method into disrepute.


Meanwhile, I will wish people well – my only concern is to see the Buteyko Method taught correctly in the West.

I congratulate all patients who have achieved freedom from their disease by practising the Buteyko Method.


K.P. Buteyko



A breathing discovery

At the end of the last century Austrian physiologists Breyer and Gering made a sensational discovery – man is the only biological specimen on earth who had not developed a correct way of breathing. All other beings know how to breathe, but not humans. Just observe those around you carefully and you will find that people breathe differently. Some breathe deeply, others superficially, some faster, others slower, with pauses and some without.




Russian Medical Scientist Professor Konstantin Pavlovich Buteyko has devoted over 40 years of research into breathing and in the process discovered that only one in ten people breathe correctly. Natural or normal breathing results in a very specific accumulated gas mixture that our organism requires. to function properly.




Traditional wisdom tells us that deep breathing is the best as it is thought to provide the most oxygen. We inhale oxygen and exhale carbon dioxide and the conclusion that is drawn is that oxygen is good for us and carbon dioxide is harmful. When Professor Buteyko was first analysing his patients he discovered that those who were sick breathed much more than those who were healthy; that is, their tidal volume, depth and frequency was greater. Could it be that “breathing deeply” is in fact contributing to ill health?



In 1871 the Dutch doctor De Costa discovered the “Hyperventilation Syndrome” whereby deep breathing in a relaxed state caused dizziness and sometimes fainting. This is often incorrectly attributed to oxygen saturation. According to the Verigo-Bohr effect, it is the ratio of carbon dioxide to oxygen which permits the release or retention of oxygen from the blood.


At the end of the last century Russian physiologist Verigo and Dutch scientist Bohr independently discovered that without carbon dioxide, oxygen is bound to the haemoglobin of the blood and simply does not work. This consequently leads to oxygen deficiency in the tissues of the brain, heart, kidneys and other organs and a raising of blood pressure.

Strange as it may seem, oxygen deficiency is not caused by lack of oxygen but by the lack of carbon dioxide! If we breathe too much we get less oxygen.




For the cells of the brain, heart, kidney and other organs, our blood requires a concentration of: 6.5% carbon dioxide and only 2% oxygen.



The function of our respiratory system is not just to push air in and out but to maintain a very specific ratio of oxygen to carbon dioxide.



When we over breathe or hyperventilate, we lose valuable carbon dioxide. According to Professor Buteyko, “hidden hyperventilation” often goes undiagnosed. When a person is acutely hyperventilating, it’s obvious and the implications to the organism are disastrous. Hidden hyperventilation often goes unnoticed. Asthmatics overbreathe three or more times the recommended amount. Long term “hidden hyperventilation” is the hinge upon which Buteyko’s discovery and method are based.



Breathe very deeply for 5-10 minutes and you may experience an asthma attack, blocked nose, dizziness, chest pains, palpitations, coughing and many other symptoms. Reducing the depth of your breathing by breathing shallowly can reverse these symptoms often within a few minutes.



Physiological norms apply to pulse, blood pressure, sugar levels, temperature and breathing as well. Ideally at rest an adult should breathe lightly, superficially, and only through the nose. A healthy person can perform light exercise and still breathe lightly, whilst a sick person requires deep breaths almost all of the time.



Many people think they breathe shallowly but in fact they breathe very deeply. Many people who suffer with asthma, allergies, bronchitis, emphysema and breathlessness will tell you they can’t breathe enough, when in fact they are breathing three or more times the normal volume of air. Professor Buteyko developed a test that can measures your depth of breathing and subsequent retention of carbon dioxide, resultant oxygenation and health. Professor Buteyko calls it the “Control Pause”. The Control Pause Breathing Test:


  • Breathe in gently for two seconds.

  • Exhale gently for three seconds.

  • Hold your breath, pinching the nose after exhaling, holding your breath until it first becomes difficult.


If you manage less than 10 seconds (on the third step) you have very serious health problems. If you can hold less than 25 seconds your health requires attention, 30-40 seconds is satisfactory and 60 and above is excellent.



We are all aware of the dangers of pollution and the declining quality of our air. Many blame asthma and other breathing disorders on pollution and the environment, yet asthma strikes in the county as well as in the cities and some people who work in very polluted environments never suffer with asthma or emphysema. Could there be another problem with the air we breathe?



The problem faced by the evolving human organism has been the depletion of carbon dioxide in our atmosphere from the tens of percent of ancient eras to the current level (1982) of 0.03%. Human evolution has dealt with this dilemma by creating an autonomous internal air environment within the alveolar spaces of the lungs. These alveoli ideally contain around 6.5% of carbon dioxide, quite a contrast to the surrounding air. The gaseous mix in the womb is also an interesting indicator of the ideal human environment – here there exists between 7/8% carbon dioxide.



Let’s take a look at what carbon dioxide does for us, and from this we can ascertain what a deficiency may mean:


  • OxygenationCarbon dioxide regulates oxygen departure from blood and a fall in carbon dioxide results in reduced oxygenation of tissue and vital organs (Verigo-Bobr Effect). Poor oxygenation leads to myriad complaints.

  • Acid/Alkali Balance and the Immune SystemCarbon dioxide, through its conversion to carbonic acid, is the most important regulator of our acid/base balance. A lowering of carbon dioxide results in a shift of the body’s pH toward alkalinity, which changes the rate of activity of all body ferments. An alkaline system is much more susceptible to virus and allergy as it compromises the immune system. A great deal of information is available about the role of pH in the process of binding of the antibody with the antigen. A deviation of the pH from a certain optimum results in a decrease in the affinity and therefore in the weakening of the immune reaction.

  • VesselsCarbon dioxide is a smooth muscle tissue dilator; therefore a shortage of carbon dioxide can cause spasms of brain, bronchi and other smooth muscle tissue. Asthma spasms and migraines are prime examples of this situation.

  • The Nervous SystemCarbon dioxide is a regulator of nervous system activity and a lowering of carbon dioxide in the nerve cells heightens their excitability, alerting all branches of the nervous system and rendering it extraordinarily sensitive to outside stimuli. This leads to irritability, sleeplessness, stress problems, unfounded anxiety and allergic reactions. Concurrent with this, the breathing centre in the brain is further stimulated, thereby causing an increase in breathing rate and a further loss of carbon dioxide, and a vicious cycle begins.

  • The Cardiovascular SystemCarbon dioxide is a regulator of the cardiovascular system. A depletion of carbon dioxide can result in angina, chest pains, high or low arterial pressure, hypertension, stenocardia and eventually sclerosis of vessels, myocardial infarcts and strokes.

  • The Digestive SystemThere is a direct relationship between the level of carbon dioxide and the activity of the digestive glands, in particular the linear relationship between the intensity of gastric secretion and the level of carbon dioxide. A shortfall of carbon dioxide can lead to ulcers and poor digestion.



Note for medical professionals:
The above reference to carbon dioxide does not specify its form (i.e. dissolved carbon dioxide gas, carbonic acid, bicarbonates, carbonates or carbamates). Furthermore the author has not explained the various shunts between defensive and compensatory mechanisms that may lead to obvious paradoxes, such as high levels of CO2 in the blood of asthmatics, and the compensating shifts between respiratory alkalosis and metabolic acidosis.

Carbon Dioxide

Carbon Dioxide,

by Yandell Henderson

On May 9, 1794, during the Reign of Terror, Antoine-Laurent Lavoisier died by the guillotine. This event closed the first and greatest chapter in the physiology of carbon dioxide: for the principle of the production of carbon dioxide and its relation to oxygen in fire and the in life which Lavoisier had discovered shortly before his death was, and still is, the most fundamental of all contributions to knowledge in this field. Truly, as his colleague Lagrange said:"It took but a moment to cut off a head, the like of which a hundred years may not reproduce."


Likeness of Life to Fire.-Lavoisier's supreme contribution to science, and particularly to physiology was the demonstration that, in their broad outlines, combustion in a fire and respiratory metabolism in an animal are identical. Both consist in the union of oxygen from the air with carbonaceous material: and both result in the liberation of heat and the production of carbon dioxide. Carbon dioxide had, indeed been discovered previously by Black in 1757, and oxygen had been described by Mayow, Scheele and Priestly. But it was Lavoisier who first showed the part played by oxygen and the process by which carbon dioxide is produced.


A century later the standard textbook of physiology in the English language was that of Sir Michael Foster of Cambridge University. This book supplied the early training of many of the physiologists who during the past 35 years have contributed to the development of respiration and to the increasing recognition of the part played in the economy of the body by carbon dioxide. The facts and conceptions presented by Foster show, therefore both the advance of 100 years from Lavoiser and the starting point of modern investigation. If the first chapter of the physiology of carbon dioxide was contributed by Lavoisier and closed with his death, the second chapter is presented by Foster, and is nearly coextensive with the 19th century; which the third chapter, with which this paper will chiefly deal, is the product of the generation that has done its experimental work in the first 3 decades of the 20th century, and from its theoretical results is now making valuable contributions to clinical medicine and surgery, and particularly to therapeutics.


Contrast Between Life and Fire.--- The most important advance in the physiology of respiration as presented by Foster, beyond the conception left by Lavoiseir, was that the oxidation in living matter, although like a fire in materials and products, is profoundly different in its process and control. If a fire is supplied with pure oxygen instead of air, it burns with enormously augmented intensity. But when a man or animal breathes oxygen, or enriched with oxygen, no more of that gas is consumed, no more heat is produced and no more carbon dioxide is exhaled than when air alone is breathed. Although clinicians still find it hard to believe, oxygen is in no sense a stimulant to living creatures. It is merely en essential food; it is a food of which the body cannot be induce to take more , or to get along on appreciably less, than its own interior regulation determines according to its needs. Even in rarefied air, or in cases of heart disease conditions in which a man may suffer severely from the deficient supply of oxygen, the body actually consumes practically a normal amount. The asphyxial symptoms are the expression of the strain on the body to obtain this amount. It gets it , or it dies.


Lavoiser had supposed that the vital combustion must occur in the lungs where the inspired air comes in contact with the blood. Spalanzani, the Italian physiologist, soon recognized, however, that in fact the oxidation does not occur in the lungs: it is in the tissues, to which oxygen is transported by the blood. That such is the fact was proved by Magnus, a German physiologist, who first extracted the gases from blood by means of the vacuum pump and showed that arterial blood contains more oxygen and less carbon dioxide than does venous blood. Then Hoppe-Seyler, one of the first of the biochemists, separated hemoglobin, the coloring matter of the red blood corpuscles, in the form of pure crystals, and showed that this substance forms a loose chemical compound with oxygen. Hemoglobin is the means by which the blood transports oxygen.


Blood Alkali as Carrier of Carbon Dioxide . ---- Later, in the 19th century, Zuntz, in Berlin, recognized that carbon dioxide, unlike oxygen, is not carried by hemoglobin, but that hemoglobin is nevertheless an essential factor in the transportation of this gas but the blood. He showed that in the blood carbon dioxide is combined with bases, chiefly as sodium bicarbonate. He thus demonstrated, for the first time, what is now generally, but rather unwisely, called the alkaline resevere. It were better to call the bicarbonates of the plasma the alkali in use ; the true reserve alkali is combined with hemoglobin and is given off to unite with carbonic acid, or to neutralize stronger acids. As carbon dioxide is given off in the lungs, the amount of alkali thus set free recombines with hemoglobin.


This mode of transportation of carbon dioxide is one of the most extraordinary features of the blood and respiration.The evidence for it rests upon 2 facts demonstrated by Pfluger and others during the great epoch of German physiology in the second half of the 19th century. One of these facts is that the blood plasma, if separated from its corpuscles, will part with little of its carbon dioxide even in the presence of a vacuum. The other fact is that all the carbon dioxide in the plasma, both that in simple solution and that combined with alkali into the bicarbonates, comes off readily if the red corpuscles of the blood are present. Thus, the hemoglobin of the red corpuscles, by supplying or recombining with alkali, dominates the capacity of the plasma to transport carbon dioxide; it thus enables the blood to take up this gas in the tissues and to give it off in the lungs under very slight differences of pressure.


Meanwhile, another problem of primary importance was attracting the attention of investigators: the problems not only of how we breathe, and why, in the sense of the need, by also why, in the sense of the cause and stimuli. It is one of the commonest observations of life that physical exertion, owing to its increased consumption of oxygen and production of carbon dioxide, is accompanied by the breathing of an increased volume of air. The need is evident. But what is the nature of the stimulus and what is the controlling mechanism which together induce this adjustment of the ventilation of the lungs to the respiratory needs of the body? This matter was long debated. Nearly every champion of every shade of opinion for more than 50 years contributed some particle of truth on one phase or another. But every contributor was in error who claimed for any one factor an exclusive control; for breathing is the resultant of many factors.


Nervous and Chemical Regulation of Breathing. ---- The factors thus revealed were 2 main classes: nervous and chemical.. Throw a bucket of cold water over a man and he draws one or more deep breaths. Irritate an afferent nerve, causing pain, and he cries out. Tickle his nose or throat and he sneezes or coughs. These are all respiratory reflexes excited by nervous impulses coming to the respiratory center. But more important than any other nervous element in breathing are the vagus nerves whose may fibers there are some which have endings in the lungs and convey impulses from them to the respiratory center in the medulla oblongata. Through these pathways, as Hering and Breuer showed, each expiratory deflation of the lungs stimulates the center to discharge a reflex to the diaphragm and other respiratory muscles inducing inspiration; and contrariwise, each inspiration induces reflexly an expiration. To this mechanism breathing owes its rhythmic character; or, as an engineer would express it, breathing is a reciprocating mechanism.


Over against this explanation, based upon nervous factors, evidence gradually accumulated indicating a chemical control of respiration. The blood flowing to and through the respiratory center was found to exert a dominating influence upon the activity of breathing. Whenever the blood was rendered venous, the center was stimulated to produce a counteracting increase of the volume of breathing. If, on the contrary, the blood were overventilated in the lungs, the activity of the center ceased for a time and apnea resulted. In this state, the subject neither breathes nor feels any desire to do so.


As this conception of the chemical control of breathing developed, its advocates separated into 2 groups. One held that it is primarily the degree to which the blood is oxygenated which influences the respiratory center and controls its activity. The other presented evidence indicating that is rather the amount of carbon dioxide in the blood which is the determining factor. In this matter also both sides of the controversy contributed experimental facts of value and each was in part correct. Respiration is, indeed, influenced fundamentally by the oxygen pressure to which the individual is acclimatized: a pressure which depends upon the elevation of his home above sea level. But acclimatization to altitude is very slow, requiring days or weeks. It is only under conditions of sudden extreme oxygen deficiency, verging on asphyxia, or after intense muscular exertion, that respiration is stimulated in fact, as we shall see later, over stimulated by an urgent demand for oxygen.


On the other hand, nature provides that in a healthy man or animal, except under intense exertion, the oxygen supply is always ample and its influence upon breathing is therefore, under normal conditions relatively slight. It is the variations in the amount of carbon dioxide produced n bodily rest and exercise that afford the stimulus inducing the adjustments of breathing to the varying energy needs of the body. Foster, in his book above referred to held that the evidence then available indicated that oxygen is a more important control than carbon dioxide. But even as early as 1885, Miescher, a Swiss physiologist, in a paper that is one of the masterpieces of physiology, had summarized all the evidence then available and reached the conclusion that it is the variations in the amount of carbon dioxide which principally induce the immediate adjustments of respiration. In a classic phrase inspired by the insight of genius he wrote: Over the oxygen supply of the body carbon dioxide spreads its protecting wings. He died before he could complete his work and his death may be said to have closed the second chapter in the history of respiration and the functions of carbon dioxide in the body.


The Breath of Life.---- The first 3 decades of the present century have witnessed an extraordinary reversal of standpoint and increase of interest in regard to the functional importance of carbon dioxide in the animal body. Moreover, discoveries in this field, which were initially purely scientific and theoretical, are now finding a wide range of clinical applications for the alleviation of suffering and the saving of life.


Before considering these matters, it will be best that the mind be cleared of certain deep rooted misconceptions that have long opposed the truth and impeded its applications. It will be seen that carbon dioxide is truly the breath of life.

The human mind is inherently inclined to take moralistic view of nature. Prior to the modern scientific era, which only goes back a generation or two, if indeed it can be said as yet even to have begun in popular thought, nearly every problem was viewed as an alternative between good and evil, righteousness and sin, God and the Devil. This superstitious slant still distorts the conceptions of health and disease; indeed, it is mainly derived from the experience of physical suffering. Lavoisier contributed unintentionally to this conception when he defined the life supporting character of oxygen and the suffocating power of carbon dioxide. Accordingly, for more than a century after his death, and even now in the field of respiration and related functions, oxygen typifies the Good and carbon dioxide is still regarded as a spirit of Evil. There could scarcely be a greater misconception of the true biological relations of these gases.


PHYSIOLOGY.-----Relations of Carbon Dioxide and Oxygen in the Body.---- Carbon dioxide is, in fact, a more fundamental component of living matter than is oxygen. Life probably existed on earth for millions of years prior to the carboniferous era, in an atmosphere containing a much larger amount of carbon dioxide than at present. There may even have been a time when there was no free oxygen available in the air. Even now, such animals as ascaris will live and be active in an atmosphere of hydrogen and entirely without oxygen. In vertebrates, the process of muscular contraction is fundamentally anaerobic.


A frog's muscle will contract effectively and repeatedly under suitable stimulation in an atmosphere of pure nitrogen. In contraction, a muscle produces lactic acid, partly by reconversion into sugar. In other words, oxygen is not one of the primary factors in muscular work. The reserve store of oxygen in the body is small. Vigorous breathing does not take place before an exertion; the exertion is first made and then the oxygen needed to clear the system in preparation for another exertion is absorbed. The demand for oxygen for this scavenging of waste and restoration of power is termed by A.V. Hill the "oxygen deficit of exercise."


On the other hand, present knowledge indicates that carbon dioxide is an absolutely essential component of protoplasm. It is one of the factors in the balance of alkali and acid for the maintenance of the normal pH of the tissues. Acapnia, that is diminution of the normal content of carbon dioxide, involves therefore, a disturbance of one of the fundamental conditions of life.


Another natural, but very obstructive misconception is that oxygen and carbon dioxide are so far antagonistic that in blood a gain of one necessarily involves a corresponding loss of the other. On the contrary, although each tends to raise the pressure and thus promote the diffusion of the other, the 2 gases are held and transported in the blood by different means; oxygen is carried by the hemoglobin in the corpuscles, while carbon dioxide is combined with alkali in the plasma. A sample of blood may be high both gases, or low in both gases. Moreover, under clinical conditions low oxygen and low carbon dioxide anoxemia and acapnia generally occur together. Each of these abnormal states tends to induce and intensify the other.


Therapeutic increase of carbon dioxide, by inhalation of this gas diluted in air, if often the effective means of improving the oxygenation of the blood and tissues. Under such conditions of acute deprivation of oxygen as those in carbon monoxide asphyxia, the body suffers from an excessive elimination of carbon dioxide: and the restoration of carbon dioxide is in itself helpful. In a drowned man or a non-breathing newborn child, the deprivation of oxygen does not cause and excess of carbon dioxide. On the contrary, in the absence of oxygen, lactic acid and other primary decomposition products of the tissues acannot be converted into carbon dioxide; for that conversion oxygen is necessary. The saying of Miescher, quoted at the end of a previous section, has therefore, a depth of truth and breadth of application greater than he could possibly have realized.


As a factor in the Acid-base Balance of the Blood.---- Modern physiology has shown that, in addition to the control and regulation exerted by the nervous system, there are many chemical substances produced in the body that influence function and form. To these active principles Starling gave the name of "hormones". Among the hormones are epinephrine ( often called adrenaline), pituitrin, thyroxin, insulin and many other products of the glands of internal secretion and other organs. Carbon dioxide is the chief hormone of the entire body; it is the only one that is produced by every tissue and that probably acts on every organ. In the regulation of the functions of the body, carbon dioxide exerts at least 3 well defined influences: (1) It is one of the prime factors in the acid-base balance of the blood. (2) It is the principal control of respiration. (3) It exerts an essential tonic influence upon the heart and peripheral circulation.


In recent years, an extensive literature has grown up on the subject of the so-called alkaline reserve, the acid-base balance, and the pH or hydrogen ion concentration of the plasma. There have also appeared many investigations and discussions of the real or assumed relations of these features of the blood to clinical acidosis and alkalosis. In the complicated adjustments of the physico-chemical equilibrium in the blood, carbon dioxide is, more than any other factor, subject to disturbance by every variation in bodily activity or heat production; but it is also that factor which is most immediately readjusted. The automatic reactions which effect this readjustment are the increase or decrease of the volume of breathing. This volume depends upon the depth more that the rate of respiration; or rather, it is the product of depth and rate. It determines the degree of the ventilation of the blood as its passes through the lungs. Normally, it is so adjusted that the carbon dioxide in the alveolar air of the lungs is maintained at a partial pressure of a little more that 5% of an atmosphere. This amount of carbon dioxide gas in the alveolar air produces exactly that amount of carbonic acid in solution in the blood needed to balance the normal amount of alkali and thus to induce and maintain normal pH. This is the principle expressed by the equation of L.J. Henderson:


pH = K x [H2 CO3] / [NaHCO3] .


If, however, because of some disturbance of the function of the kidneys or other organs, the blood alkali in use is not of normal amount, the pH of the blood would also be rendered abnormal, except for the counteracting control of respiration over the carbon dioxide in the alveolar air and thus over the carbonic acid in solution in the blood. Whenever the blood alkali is lower than normal, respiration increases and maintains a more vigorous pulmonary ventilation. The object and effect of its augmentation are that alveolar carbon dioxide is mixed with more fresh air and diluted. Consequently, the carbonic acid of arterial blood-pressure is decreased proportionally. This is the explanation of the increased respiration occurring in the acidosis of acute nephritis and in diabetic coma, and developing into air hunger as death approaches: an increase of respiration is the natural compensation for a decrease of blood alkali. On the other hand, if the amount of carbon dioxide is deficient simultaneously with a normal or excessive blood alkali, respiration is decreased or fails entirely. These respiratory reactions depend upon the relating influence of carbon dioxide in its chemical balance with the blood alkali; for, if the carbon dioxide and alkali are even slightly out of balance, the respiratory center is powerfully stimulated or depressed.


Whether the physiological reactions to carbon dioxide are due directly to a specific effect of this substance, or rather to the pH of the blood and of other humors in which carbon dioxide is an important factor, is still under active investigation. It is, however, noteworthy that the existence of these reactions renders invalid much of the now prevalent conception of the chemistry of clinical acidosis and alkalosis. It is not correct chemistry or physiology to infer that, because the amount of the alkali in use is high or low, the pH of the blood must be correspondingly affected. A high or low blood alkali needs merely a corresponding affected. A high or low blood alkali needs merely a corresponding decrease or increase of the volume of breathing for its compensation to afford an normal pH. If, therefore, in nephritis or diabetes or other disorders, the pH is really abnormal and the blood actually becomes even slightly more acid or more alkaline than normal. There must be some disturbance of the respiratory regulation of the alveolar carbon dioxide as yet not understood. A normal regulation of the carbon dioxide pressure is adequate to compensate either a high or a low blood alkali in practically all conditions compatible with the continuance of life.


The part normally played by the kidneys and the influences of abnormal conditions and processes in them in other organs in determining the amount of alkali in use in the blood, both in health and in such disorders as diabetes and clinical acidosis and alkalosis, are beyond the scope of this article. The problems which these matters present are, indeed, as yet only incompletely analyzed.


In the Control of Respiration and the Circulation.--- The modern development of the knowledge of the part played by carbon dioxide in the control of respiration began with a classic paper by Haldane and Priestly, entitled "The Regulation of the Lung Ventilation," and was followed by other important papers by Haldane and Douglas. In these papers it was shown by observations on normal men that breathing quite unaffected either by inhalation of oxygen-rich air by such a moderate decrease of oxygen as occurs on first going to an altitude. On the other hand the breathing changes its volume automatically in such close adjustment to the amount of carbon dioxide produced in the body that the alveolar air is kept nearly constant in this respect. Carbon dioxide is the chief immediate respiratory hormone.


A few months after the first paper by Haldane and his collaborators showed the influence of carbon dioxide upon respiration, Henderson had his collaborators began the publication of a long series of papers dealing with the influence of carbon dioxide upon the circulation. They showed that acapnia may induce acute disturbance of the heart and failure of the peripheral circulation. These conditions resemble the functional depression of shock in patients after prolonged anesthesia and major operations. On the other hand it was found that if the carbon dioxide content of the body is conserved by partial rebreathing, the vitality of an animal, even under prolonged and extensive operation and trauma, is but little depressed.


These observations upon the circulation showed also that in animals reduced to a state of shock the carbon dioxide of the blood, or as it now be generally termed, the alkaline reserve, is greatly reduced. This experimental result was later confirmed by the observations of Cannon upon wounded soldiers during the war.


The observations upon the respiration of animals under a mode of anesthesia that was intentionally made to imitate inexpert administration showed that the failure of breathing which was formerly one of the principal hazards of the operating room is largely due to excessive breathing during the stage of excitement. If, during the initial stage of anesthesia, an excessive elimination of carbon dioxide is induced and then the sensitivity of the respiratory center is depressed by a sight excess of anesthetic, respiration ceases. It does not return until the chemical stimulus of the blood gases and the sensitivity of the respiratory center are sufficiently restored to induce again the natural activity of breathing.


THERAPEUTICS. ----In Anesthesia.--- In 1920, Henderson, Haggard and Coburn carried their observations to the clinic and found that when inhalations of carbon dioxide ( 8% ) in air were administered to patients after major surgical operations under open ether anesthesia, the effects were strikingly beneficial. With the return of deep breathing, the cyanosis then common after anesthesia disappeared. The cutaneous circulation improved. The skin changed in color and temperature, from blue- gray and cold to pink and warm. The volume of the pulse, previously thready, rapidly became full; and arterial pressure was restored to normal. Owing to the increased volume of breathing, the anesthetic (ether) was rapidly ventilated out of the blood and consciousness returned within a few minutes, even after profound anesthesia. Nausea and vomiting were either greatly reduced or entirely absent and after the inhalation the patient dropped off to sleep.


In continuation of these observations, White found that when slow hemorrhage occurs after operations upon the brain, the rate of breathing gradually decreases until death is imminent. In several of such cases life was saved by stimulation of respiration with inhalation of carbon dioxide.


The use of this inhalation has now become general in connection with anesthesia. Nearly every American anesthetic apparatus now has an attachment for a cylinder of carbon dioxide, or of a mixture of carbon dioxide and oxygen. By this means any tendency to failure of breathing on the operating table is counteracted. At the close of the operation, an inhalation of carbon dioxide is given to stimulate respiration and induce rapid elimination of a large part of the anesthetic. By this inhalation a vigorous heart action and the tonus of the peripheral circulation are also restored.


Postoperative Atelectasis and Pneumonia.---Prophylaxis.--- From the use of carbon dioxide for the purposes just described, another even more important application has developed, i.e., the prevention of postoperative atelectasis and pneumonia. Many observers have noted that after major surgical operations, the vital capacity of the lungs is often reduced to as little as one-third of the preoperative volume. The diaphragm may be elevated toward the thorax by several centimeters. In x-ray pictures, this condition of partial collapse of the chest is found to continue to some extent for several days. The position of the thorax is essentially like that which occurs in a normal man for a few minutes after vigorous forced breathing. It is, therefore, a phenomenon of acapnia.


This acapnial position of the thorax may leave considerable parts of the lungs unventilated. The airways to these parts may become obstructed and the occluded air is then absorbed into the blood.


As a result, atelectasis of a lobe, or even a massive collapse of an entire lung, may develop. From this condition, as Coryllos and Birnbaum have demonstrated experimentally, pneumonia may develop, for if pathogenic organisms happen to be present, they find in an atelectatic lung conditions favorable to their growth.


The essential correctness of this conception of the origin of postoperative atelectasis and pneumonia is attest by the prophylactic and therapeutic means that have been found effective to counteract or prevent them. In many surgical clinics in America and Germany, results have been obtained which show that when the inhalation of carbon dioxide is administered to all cases after anesthesia and operation, the lungs are reexpanded, the tonus of the respiratory muscles is restored, atelectasis is prevented, and the risk of postoperative pneumonia is virtually eliminated.


Pneumonia.---The possible benefits of a similar inhalational treatment of medical pneumonia, for example after influenza, are just now under active investigation. Henderson, Haggard, Coryllos and Birnbaum have shown that in dogs, in which pneumonia has been experimentally induced, the lungs may be cleared and the pneumonia cured by placing the animals in an atmosphere of about 8% carbon dioxide for 12 to 24 hours. In support of the claim that these are real cures is the fact that pneumococci are inhibited in growth or even killed by a lowering of pH no greater than carbon dioxide may induce. A lowering of the pH by carbon dioxide contributes also to the autolysis and liquefaction of the exudate responsible for the consolidation of the lungs in pneumonia. Many cases of pneumonia have now been treated with inhalation of carbon dioxide in oxygen; and a special tent for this treatment is being introduced by Henderson and Haggard. It is believed by those who have used it that this treatment is decidedly superior to that with oxygen alone.


Asphyxia.---Very similar to the use of carbon dioxide inhalation after anesthesia is the modern treatment of carbon monoxide asphyxia. This form of asphyxia is the cause of many thousands of deaths annually. Its commonest causes are city manufactured gas, which usually contains 20 to 30 % of carbon monoxide, and the exhaust from automobiles. Carbon monoxide forms a combination with hemoglobin which displaces oxygen. The compound is not so firm, however, as was once believed, for the carbon monoxide may be, in turn, displaced. The oxygen-carrying power of the blood is thus restored. The critical feature of carbon monoxide poisoning is the asphyxia, especially of the nervous system, because of the diminished capacity of the blood to transport oxygen. It seemed, therefore, at first that inhalation of oxygen would be the logical treatment. In practice, however, oxygen alone was found to be much less beneficial than was expected.


Investigating this problem, Henderson and Haggard found that in the development of carbon monoxide asphyxia the victim overbreathes and blows off an excessive amount of carbon dioxide. He thus develops acapnia, as well as anoxemia. On removal from the noxious atmosphere, the victim may exhibit a marked depression of breathing. The administration of oxygen is therefore, only slightly effective; for it is not adequately inhaled.


In experiments on asphyxiated animals these investigators showed that by administering a mixture of oxygen and carbon dioxide the respiration could be so stimulated, and the elimination of carbon monoxide so accelerated, that rapid recovery was induced. In the beneficial results, the relief of acapnia is almost as important as the elimination of carbon monoxide and the restoration of an ample supply of oxygen.


A special form of apparatus, the H-H Inhalator, for the administration of a mixture of oxygen and carbon dioxide to asphyxiated patients was, therefore, devised and has been widely introduced. This treatment has been so successful that many thousands of these inhalators are now in use: several hundred, for instance, in metropolitan New York, and a number corresponding to the population in Chicago and other cities. The rescue crews of the fire and police departments, the gas and electric companies, and now also the hospital ambulances generally have them. At first a mixture of 5% carbon dioxide in oxygen was used, but 7% has proved even more beneficial.


The value of this treatment is not merely for the saving of life, but also for the prevention of such postasphyxial sequelae as pneumonia, injury to the heart, and permanent nervous impairment. In many cases of brief but intense asphyxiation the patient is completely restored within an hour; he may then voluntarily and safely go back to work.

The same treatment is effectively used for resuscitation from a wide range of other noxious gases occurring in industry.

Asphyxia of the Newborn.---Out of this treatment of carbon monoxide poisoning has developed the use of inhalation for the relief of a far more common form of asphyxia: that of the newborn. The story of this development is interesting. In it the men of the rescue crews of the Chicago Fire Department have played somewhat the same part that the milkmaids immune to smallpox did in the discovery of vaccination. 


Many times it happened that a physician in Chicago who had seen a resuscitation of a case of carbon monoxide asphyxia had occasion soon after to deliver a baby that would not breathe. After swinging, spanking, and dipping the child in cold and hot water, the accoucheur, unable to induce active, natural breathing, thought to telephone for one of the rescue crews and their inhalator. The ministrations of these men were in many cases so successful that within a couple of years the fire department had developed a considerable practice in this field. With justifiable pride, it claimed the saving of several hundred babies.


When this information came to the attention of the writer it occurred to him that on theoretical grounds inhalation of oxygen and carbon dioxide is exactly the method that should be most effective in combating asphyxia of the newborn. As a result of this discovery, chemical stimulation and support for the depressed respiratory center of the newborn child by inhalation of carbon dioxide is now rapidly replacing the older, and often ineffective, methods of resuscitation depending upon cutaneous stimulation.


Neonatal Pneumonia.---Prophylaxis.--- The lungs at birth are atelectatic. The first cry effects a partial dilation. Later breaths should dilate them further; but the dilation is often incomplete for several days, or even for some weeks. If during this time, pathogenic organisms happen to be present, they find conditions favorable for their growth in any part of the lungs that are still atelectatic. The number of deaths from this cause during the neonatal period is often as high as 4 for each of 100 live births. To forestall this hazard, it has long been the custom to stimulate the child to cry at least once daily. For this purpose some painful stimulus, such as stinging of the soles of its feet with an elastic rubber band, is applied. Experience demonstrates, however, that a premature or weak child may not be adequately stimulated and pneumonia may develop. A more humane, scientific and effective method of inducing dilation of the lungs is the routine administration to all babies during the first week or two of life of 5 or 10 minute inhalations of oxygen and 7 or 8 % carbon dioxide. The mixture is entirely safe for general use by nurses and midwives. Higher concentrations can be used effectively on difficult cases, but preferably only by those who have experience in the use of such concentrations in connection with anesthesia.


Angina Pectoris and Intermittent Claudication.----In most of the applications of inhalational treatment discussed in the foregoing pages the influence of carbon dioxide upon respiration is chiefly involved. The equally important influences of carbon dioxide upon the hear and the peripheral blood- vessels have not as yet been exploited to an equal degree. Henderson and his collaborators showed many years ago that under certain experimental conditions the heart tends to develop a partial tetanus or cramp, and that this condition may be overcome by means of carbon dioxide. They showed also that, owing to the loss of muscular tonus in animals under prolonged anesthesia and operation, the blood stagnates in the peripheral vessels, the venous return to the right heart decreases progressively, and the circulation finally comes to a standstill.


With these considerations as a physiological background, the influence of carbon dioxide inhalation has recently been tried on several cases of angina pectoris. This is not an emergency treatment, but a therapy for prolonged application. It is administered for 10 to 15 minutes at a time 2 or 3 times a day. The method of inhalation is essentially like that applied by Henderson,, Haggard and Coburn, and by White, after anesthesia and operation. As the inhalation consists of carbon dioxide in air, instead of in oxygen, its cost, aside from the control apparatus, is small.


The effects of this treatment are a distinct improvement in the color and temperature of the lips and skin, indicating an effect upon the peripheral circulation somewhat like that of amyl nitrate. Arterial pressure and the pulse rate are not increased, although a markedly fuller circulation is evident. The sense of oppression in the chest and the pain referred to the shoulder and arm is considerably decreased; it may cease altogether for some hours after the inhalation. After some weeks of daily inhalations, the capacity to take moderate exercise is markedly increased.


This inhalation has also been used upon a few cases of intermittent claudication. A marked improvement in the local circulation resulted both under the inhalational and as a cumulative effect of the treatment for some weeks. When it was discontinued , the patients soon relapsed into their previous condition.


Drowning and Electric Shock.--- The accepted treatment of the victims of drowning and electric shock is the Shafer prone pressure method of artificial respiration. Experience has demonstrated that the return of natural breathing is considerably aided and accelerated by the administration oxygen and carbon dioxide from an inhalator, while artificial respiration is being applied. Not only are the lungs thus supplied with a high concentration of oxygen, but the depressed respiratory center is also stimulated by the carbon dioxide to an earlier renewal of neural activity than would otherwise occur.


Catatonia.---Finally, mention may be made of the extraordinary observations reported by the late A.S. Lovenhart, in which he found that inhalation of carbon dioxide to cases of catatonia induced a temporary restoration of intelligence and mental responsiveness. The simplest explanation of the results in these cases is attained by postulating an habitual contraction of blood-vessels in the brain of the catatonic patient, similar to that in the heart and limbs of the cases discussed in the previous section. If this view is correct, the beneficial effects of the inhalation are due to improvement in the circulation in the brain under the influence of carbon dioxide upon the finer blood vessels.


Yandell Henderson,
New Haven, Connecticut



The extensive literature of this subject may be found through the references accompanying the following works: Haldane, J.S.: Respiration, Yale University Press, 1922 Henderson, Y.: Physiological Regulation of the Acid-Base Balance of the blood and Some Related Functions, Physical. Rev. 5:131 ( April) 1925; The Dangers of Carbon Monoxide Poisoning and Measures to Lessen These Dangers, J.A.M.A> 94: 179 ( Jan.18) 1930; Acapnia as a Factor in Post-operative Shock, Atelecasis and Pneumonia, Ibid. 95: 572 ( Aug.23) 1930; Incomplete Dilation of the Lungs as a factor in Neonatal Mortality, Ibid. 96: 495 (Feb.14) 1931.




“Carbon dioxide is the basic nutrition of every life form of earth.
It acts as the main regulator of all functions in the organism;
it is the main internal environment of the organism; it is the vitamin of all vitamins.”
– KP Buteyko

Russian scientist and medical doctor Konstantin Buteyko, in 1952, discovered that the real cause of asthma and other related diseases is a radical depletion of CO2 – carbon dioxide – in the lungs. This isn’t so strange when we learn that oxygen cannot be assimilated by cells without adequate amounts of CO2. There is only 0.03% carbon dioxide in the atmosphere today. Yet to absorb oxygen a healthy body requires about 6.5% carbon dioxide in the alveoli of the lungs. Therefore your lungs act to trap in some of the carbon dioxide produced by your body. Should the level of carbon dioxide in human lungs fall to 3%, it is fatal.


According to Buteyko’s research, asthmatics and sufferers of other related conditions have adopted a breathing pattern which causes them to release more carbon dioxide than they produce. To prevent the level from dropping to far, the body has developed certain defence mechanisms. These include constriction of the bronchial muscles and increased production of mucus in the membranes of the breathing passages.


Signs of overbreathing are lightheadedness, dizziness, poor concentration, shortness of breath, over sensitivity of the airways, excessive production of mucus, blocked or runny nose, mouth breathing, palpitations, skipped heart beats, muscular spasms, different degrees of anxiety, tension, apprehension, fatigue, insomnia, abdominal bloating, loss of consciousness, and the list goes on!


Paradoxically, while overbreathing means we are taking in more air, we are actually receiving less oxygen in vital areas of our brain and body.


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