Written by: Dr. Jon Barron

Back in 2007, I wrote a four part series on the anatomy and physiology of the cardiovascular system. The idea behind the series was that by looking at the basic anatomy and physiology of the various body systems from a doctor's perspective, we gain a unique perspective. Once we understand the underlying basis of medical treatments used to correct problems in that system, we can make informed decisions as to which of those treatments and medications actually make sense for us...and, more importantly, what natural alternatives might actually work better. So with that in mind, let's go back to our exploration of anatomy and physiology by exploring the respiratory system.

The primary functions of the respiratory system



At its simplest level, the respiratory system, for all its complexity, really has just two primary functions. First, it is an exchange system that swaps out carbon dioxide, the byproduct of metabolism, for oxygen. In addition, it is instrumental in maintaining the acid/alkaline pH balance in your body through the bicarbonate buffer system. This is a simple concept to understand vis-à-vis the respiratory system once you realize that when carbon dioxide dissolves in water, it can react with that water to produce carbonic acid, which acidifies the blood. This means that eliminating carbon dioxide in the blood reduces acid levels both in the blood and in the body tissue served by that blood.



Understanding what we're trying to do when breathing is more important than it might first seem. With understanding comes the first awareness of what we can do to improve those functions.



Anatomy of the respiratory system



Surprisingly, the respiratory system and the gastrointestinal system are closely linked by evolution. Or if you prefer the shorter term perspective, the respiratory system grows out of the gastrointestinal system during the development of the fetus in the womb. This linkage can easily be seen in the shared connections in the two systems. The mouth, tongue, nasal cavities, and esophagus are involved in both respiration and eating. In fact, this linkage can at times be problematic as it puts the lungs at risk of aspiration during swallowing and vomiting.



In essence, the respiratory system consists of a series of tubes for conduction of air, then distribution of that air to the remotest corners of your lungs, and finally the exchange of gases at the capillary level. Air is inhaled through the nose and mouth, then down through the "airways," passing from the larynx and trachea and then into a rapidly dividing series of about 23 generations of bronchi and bronchioles. The bronchi are comprised of a series of cartilaginous rings that keep them relatively rigid. But by the time you reach the smallest of the conductive tubes, the bronchioles, the cartilage is gone and the tubes are flexible -- subject to opening and closing through muscle action.



In summary, the larynx, trachea, bronchi, and their smaller divisions perform pulmonary ventilation, which is simply the movement of air. The bronchioles and alveoli, which are found at the far end of the respiratory system, perform pulmonary respiration, which is the actual exchange of gases.



There are nearly 50 distinct types of cells that have been identified in the lungs -- at least 12 can be found in the airways. In addition, mucus is secreted onto the surfaces of the airways by glands and by "goblet cells" abundantly present on bronchial surfaces. This mucous rests on a thin layer of an electrolyte solution and covers much of the bronchial surfaces. In addition, a large number of cells with hair like extensions called cilia can also be found along the entire length of the airways (at least in a person who doesn't smoke). The purpose of the cilia is to capture any particles or smoke that enters the air passages, mix them with the mucous that lines the passageway, and then beat that mixture back up through the passageway until it is expelled from the lungs. From there it is either coughed and expectorated out of the body or swallowed. As a side note, approximately 500 ml of this mucous (one pint) is swallowed every day. Any damage to this system, such as that caused by smoking which destroys the cilia, leaves one prone to develop respiratory infections and bronchial dilation, which narrows the airways and restricts the ability to breathe.



Upper airway

The first part of the airway (nose and mouth) is devoted to air conditioning -- warming up cold air, cooling hot air, moisturizing dry air, etc. before it enters the lungs. The nasal cavity (also called the nasopharynx) is lined with mucous membranes, which contain many folds to provide a large surface area. This facilitates temperature and moisture control. It's the reason you get a runny nose in cold air as the nasal tissue releases large quantities of fluid in an attempt to moisturize the cold dry air. In addition, the mucous produced by the membranes is thick and sticky so as to catch dust and particulate matter so it does not enter the lungs.



The epiglottis is made of cartilage and serves to prevent food or liquids from entering the lungs. When you swallow, the swallowing action causes the trachea to rise up. At the same time, the action of the tongue presses the epiglottis down on top of the trachea -- thus closing off entry to the lungs. (Note: this action can be seen by watching the Adams apple which sits above the trachea and is part of the voice box as it rises up with the trachea each time you swallow.) Talking while swallowing will defeat this mechanism, leading to aspiration (the accidental sucking in of food particles or fluids into the lungs). Also, sometimes as people age, the mechanism works less efficiently, thus causing people to aspirate more and go into painful coughing fits in an attempt to force the food or liquid back out of the lungs. Major and minor episodes of aspiration contribute to the terminal stages of many diseases, and aspiration appears to play a role in a variety of chronic disorders, such as cough, bronchial asthma, bronchiectasis, and pulmonary fibrosis.



Lower airway

Like the heart, surrounded by the pericardium, the lungs are likewise enclosed in a two piece membrane called the pleura lining. This is a thin membrane which lines the inside of the chest cavity and also covers the lungs. The two "pleural cavities" (one for each lung) are enclosed compartments, with normally only a film of lubricating fluid between the layer lining the chest (parietal pleura) and the layer covering the lungs (visceral pleura).



The "visceral" layer covering the lungs is continuous with the "parietal" layer that covers the inner surface of the chest cavity -- like a balloon folded over on itself. The thin layer of fluid, which separates these two layers amounts to less than 10 ml (about 1/3 of an oz) total in the normal adult lungs. This fluid contains both mesothelial cells and a significant concentration of mucopolysaccharides, which acts as a lubricant for the smooth movement of the pleural layers against one another. The two layers continually tend to pull away from each other, because of the stretched elastic condition of the lungs -- an important factor in the mechanics of breathing. If the chest wall is penetrated by a wound, air is readily sucked into the pleural cavity, separating the two pleural layers and collapsing the lung.



Air is conducted from the nose and mouth down into the lungs by the trachea (a tube made primarily of cartilage that serves only one purpose -- to conduct air). At the bottom of the trachea, the passageway splits into two bronchial tubes called the mainstem bronchi -- one heading into each lung. The mainstem bronchi then divide progressively into smaller and smaller segmented bronchi as they spread into the lungs. The bronchi are, like the trachea, are primarily composed of inflexible cartilage. Again, they are used for conduction of air only. At the lowest or smallest level, however, the bronchi change. The cartilage is mostly gone, and the composition is now mostly flexible muscle. These terminal bronchi are called bronchioles. As we saw with the cardiovascular system, the muscle tissue at this level allows the bronchioles to expand and contract -- thus directing air flow to the different parts of the lung as needed. The whole system is known as the tracheal-bronchi tree -- and it in fact looks like a tree if you turn it upside down, with the trachea serving as the trunk of the tree.



Note: the muscle tissue at the level of the bronchioles can sometimes present a problem. In some cases, this tissue is extremely sensitive and hyper responsive to allergens. In those cases, the muscle can lock the bronchiole in a closed state. At that point air can still be forced past the bronchiole into the alveolar sacs, but because of the constriction, it cannot leave -- which makes breathing extremely difficult. This condition is known as asthma. (More on this later in the series.) Incidentally, the wheezing that asthmatics experience is merely the sound of air trying to rush through the constricted tubing.



After the division of the mainstem bronchi, each lung divides itself into three lobes -- although in the left lung, the upper and middle lobes have merged together, making it look like there are only two lobes. The lobes are then divided into smaller segments named after the bronchi that go into them. From a surgical point of view, it is far easier to remove an entire lung, as opposed to just a piece of lung since you only have to staple off the one large bronchi and one main blood vessel. Lobes are also fairly easy to remove in that you are still dealing with just a handful of bronchi and blood vessels. But if you try and remove a piece of a lobe, you must close off dozens of bronchioles and blood vessels.



Exchange system

At the end of all the bronchioles are the alveoli, the microscopic air sacs that serve as the exchange system of the lungs. It is the alveoli that interact with the vast network of tiny pulmonary arterioles, venules, and capillaries -- exchanging oxygen for carbon dioxide and refreshing the blood. The network of arterioles and venules literally cover the alveolar sacs complete with a spider web like network, providing access to every square inch of lung tissue. The actual exchange of gases takes place at the level of the pulmonary alveolar capillaries -- the tiniest part of the system.



The alveoli



Alveoli begin to appear in the walls of the 17th generation of bronchioles. By the 20th generation of bronchioles, the entire wall of the airway is composed of alveoli. But the actual alveolar sacs, the bottom line of the lung so to speak, make their appearance at the 23rd generation of alveoli. There are approximately 300 million alveoli within the lungs, providing a surface area about the size of a tennis court. The barrier separating the pulmonary capillaries from the air in the alveolar sacs is composed of a layer of endothelial cells, a small interstitial space, and a layer of pulmonary epithelial cells known as pneumocytes. The exchange of oxygen for carbon dioxide in blood cells takes place across this barrier.



The tissue separating the endothelial cells and the epithelium of the lungs contains elastic, collagen fibers that give structural integrity and elasticity to the pulmonary tissues. When the chest cavity is opened, it is the elasticity of the lungs that acts to expel all of the air remaining in the lungs, which then collapse. This becomes significant when we talk about emphysema. One of the effects of emphysema is that it destroys those elastic fibers, which severely impacts the ability of the lungs to adequately contract, significantly impacting the ability of the patient to breathe. At the other end of the spectrum, however, an overgrowth of fibrous elastic tissues in the lungs happens in patients with pulmonary fibrosis and is responsible for the difficulty that they experience during inhalation -- both in terms of the ability of the lungs to expand and contract and the ability of carbon dioxide and oxygen to freely pass between the pulmonary capillaries and the alveoli.



Another issue to consider is that for this system of gas exchange to work, the alveolar sacs must be composed of many, many separate alveoli so that the sac itself looks something like a bunch of grapes. The reason the multitude of alveoli is necessary is that they provide a vast surface area to accommodate the multitude of pulmonary capillaries required to "feed" the system and exchange sufficient gases. (As we mentioned a couple of paragraphs ago, in a pair of healthy lungs, the surface area is equivalent to that of a tennis court.) In some diseases, such as emphysema, the walls of the individual alveoli break down leaving you with one sack as opposed to "the bunch of grapes." The net effect is a dramatically reduced surface area of the lungs, thereby limiting the ability of the lungs to exchange gases -- thus the resulting shortness of breath. But more on this later.



It is important to note that the lungs (and for the most part we're talking about the alveoli) are not actually hollow, but rather, sponge like. If you cut a section of the lung, it does not look like a balloon, but like a sponge. And in fact, if you squeeze the tissue, tiny little bubbles come out -- just like squeezing a sponge.



It should also be noted that the alveoli are extremely susceptible to complications if any foreign particles or fluids enter them since they have no good mechanism for their removal. Pneumonia is often the end result. In fact, the defense mechanisms to prevent this are actually in the trachea and large bronchi, which, as we discussed earlier, are lined with cells that have a vast area of hair like projections called cilia that beat upwards in an attempt to move the particulate matter (including cigarette smoke, air pollution, or coal dust) out into the throat, where it can be cleared by coughing or clearing the throat. It's probably worth mentioning that one of the first effects of smoking cigarettes or inhaling heavily polluted air is that you destroy these cilia -- and thus the ability of your lungs to protect themselves from further smoking or exposure to particulate matter. Once started, it's a vicious circle.



Diaphragm and chest wall

The last part of the respiratory system we'll talk about is the diaphragm, which is a large, sheet-like muscle. It separates the thoracic cavity, which holds the lungs and heart, and the abdominal cavity, which holds the stomach, intestines, kidneys, and liver. Like the cavities it separates, it too is comprised of two distinct portions. The costal portion is attached to the ribs and is responsible for ventilation. The ribs meanwhile, which define the chest wall, are connected by two layers of intercostal muscles. The outer layers run diagonally downward and forward from the upper to lower ribs and act to lift the chest cavity. The internal intercostals run diagonally in the opposite direction and assist in exhalation. The scalene muscles run from the first five vertebrae to the first two ribs and lift the chest cage during inhalation.



The diaphragm is crucial for breathing and respiration. During inhalation, the diaphragm contracts, thus enlarging the thoracic cavity (the external intercostal muscles also participate in this enlargement). This reduces intra-thoracic pressure. In other words, by enlarging the chest cavity, you create suction that draws air into the lungs. When the diaphragm relaxes, air is exhaled by the elastic recoil of the lungs and the tissues lining the thoracic cavity in conjunction with the abdominal muscles, which now push inward and help the diaphragm rise up and shrink the size of the chest cavity forcing air out.



The second portion of the diaphragm consists of the crural fibers, which surround the esophagus. These fibers also contract during inhalation but have a relatively minor effect on respiration. Their primary function is that they relax when food is swallowed. The crural diaphragm also relaxes when vomiting, in contrast to the costal diaphragm, which contracts with the abdominal musculature to increase intra-abdominal pressure in an attempt to force the vomit upward -- oftentimes with great force. (Think of the movie, The Exorcist.) The crural diaphragm acts in concert with the smooth muscle of the esophagus to prevent the reflux of food and gastric fluid into the esophagus.



It should also be noted that the diaphragm is involved in helping to prevent acid reflux by exerting pressure on the esophagus as it passes through the esophageal hiatus. Malfunctions here are known as hiatal hernias.



Lung facts



Like virtually all the systems and organs in our body, the lungs are a marvel of engineering and function. Awake or asleep, conscious or unconscious, our bodies breathe automatically without thought on our part.



~The normal human lungs weigh about 2 lbs or 1 kg, of which 40% to 50% is

blood.

~New babies at rest breathe between 40 and 50 times per minute. By age five it

decreases to around 25 times per minute.

~At rest, an adult breathes about 14 to 16 times per minute. After exercise it

could increase to over 60 times per minute. Note: these rates are fixed. After

years of doing yoga breathing exercises, my normal breathing rate is about six

times per minute. It used to drive doctors crazy on the rare occasions I would

have a physical. There are some people who believe that slowing down the rate

of breathing slows down the rate of aging. I don't know if that's true, but after

61 years, I'd have to say, "So far so good."

~On average, you breathe 23,000 times a day and about 600 million breaths

during your lifetime.

~Each time you breathe you inhale approximately one liter of air (or up to 3 liters

of air with a full inhalation). That works out to about 600,000 cubic meters

(785,000 cubic yards) of air during your lifetime.

~As a side note, because you breathe so many molecules of air during your

lifetime, those same molecules get shared by everyone else on the planet as

they breathe. Or to look at it another way, with every breath you take, you are

breathing billions of molecules of air that have previously passed through the

lungs of Genghis Khan, Mary Magdalene, Albert Einstein, or Mohammed -- take

your pick from any name in history. It's an amazing concept when you think

about it.



Wrapping up on the anatomy of the respiratory system



Let's take a break here. With the next issue, we'll pick up with an exploration of the physiology of the respiratory system -- how it actually works and how gases are actually exchanged. After that, we'll move into an exploration of what can go wrong and what you can do about it. Conditions we'll cover include:



~COPD

~Emphysema

~Asthma

~Allergies

~Bronchitis and flu

~Bird flu

~Pneumonia (can be triggered by aspiration -- as happens with dolphins

and whales)

~Cystic fibrosis

~Pulmonary fibrosis

~Pulmonary embolism



When we discuss those conditions, we'll get specific as to how you can help deal with them, but for now, let's wrap up with a look at three things you can do now to improve the health of your respiratory system.



Exercise your lungs



In my newsletter on Exercise, I talked about the importance of resistance breathing. Proper breathing is a topic worthy of its own newsletter, but for now, let's just focus on the advantages of resistance breathing. The concept is simple: putting a device in your mouth that restricts (in a controlled manner) your inhalations and exhalations, which forces your lungs to work harder. This, in turn, strengthens the muscles that makes your lungs work and increases their capacity. There are a number of such devices widely available on the internet and in health magazines. They tend to run $20-40. The investment is well worth it since this type of exercise can significantly improve the strength of your respiratory muscles and increase your lung capacity.

How much of a benefit are we talking about?



Studies have shown that these devices can increase breathing endurance by close to 300%. Considering how fundamental oxygen is to health, it's not hard to see the short and long-term health and performance advantages of doing so.



And for those looking to duplicate what I did with yoga breathing, the exercises I practiced were



~Kapalabhati

~Alternate nostril breathing

~Bhastrika, which you will want a teacher to guide you through

~Watching your breath. You can lie on your back for this exercise. Just visualize

yourself rising and expanding with each inhalation, and floating out on the breath

with each exhalation. And enjoy the spaces between the breaths. Don't force it.

Just watch. If after inhaling, you don't feel like exhaling immediately, don't. Just

enjoy the sensation of rising and expanding. And if after exhaling, you don't feel

the need to inhale immediately, don't. Just enjoy the sensation of floating on

your breath until it's time to inhale again. Don't force it. Just watch and breathe.



Proteolytic enzymes



Regular use of a well designed proteolytic enzyme formula can:



~Reduce swelling of lung tissue, including the bronchioles

~Reduce allergies

~Relax and expand your bronchioles

~Thin and clear mucous from the lungs

~Help heal scars in your lung tissue

~Increase the ability of your body to utilize oxygen



Raise your pH



Although your body's buffer systems will do everything in their power to maintain your blood's proper pH, you can take a tremendous burden off your body and your respiratory system in particular in accomplishing this task by taking alkalinizing supplements or treated water to raise your pH. You have a number of options including, but not limited to:



~Alkalinizing drops -- for example

~Alkaline trace minerals -- for example

~ Water Ionizer -- for example



And that's it for now. We'll pick up in the next issue with an examination of the physiology of the respiratory system.



For more information on the Respiratory System:



Part 2, The Physiology of the Respiratory System

Part 3, Diseases of the Respiratory System





Jon Barron's Alternative Health Newsletter

http://www.jonbarron.org/

Copyright © 2002-2009 The Baseline of Health Foundation. All rights reserved.

Baseline of Health® is a Registered Trademark of Jon Barron

About this talk
Researcher Kamal Meattle shows how an arrangement of three common houseplants, used in specific spots in a home or office building, can result in measurably cleaner indoor air.

About Kamal Meattle
With its air-filtering plants and sustainable architecture, Kamal Meattle's office park in New Delhi is a model of green business. Meattle himself is a longtime activist for cleaning up India's air.



Full bio and more links

This is a seven part series about the repertory system. Each part focuses on one particular section of the flawless system and explains why a creator designed the system.

In our last newsletter, we explored the anatomy of the respiratory system -- its structures and patterns. In this issue, we continue with Part 2 of the series by discussing the physiology, or functioning, of the respiratory system. This is crucial, since once we understand the parts of the system and how they work, we can explore those things that can go wrong with those functions...and what natural health alternatives exist to correct them.



Four areas of respiration



Any discussion of the function of the respiratory system has to begin by breaking that function down into its four component parts, or areas. I'm not talking about inhalation and exhalation (or expiration as doctors refer to it) here, but rather the four distinct areas in which the act of respiration takes place in the human body. These are



1. Pulmonary ventilation

2. External pulmonary respiration

3. Internal tissue respiration

4. Cellular respiration



1. Pulmonary ventilation

To a large degree, we covered this in our last newsletter as part of our discussion of the anatomy of respiration. But now, given a different context, let's reexamine this area of respiration. In pulmonary ventilation, outside air (aka room air) is taken into the body. This occurs through both the nose and mouth, which provides redundancy. If the nose is plugged, we breathe through our mouth, for example. In addition, this dual channel provides emergency capacity for stress situations such as when running -- we breathe through both the mouth and nose. Room air is composed of 80% nitrogen, 20% oxygen, and trace gases including water vapor, argon, and carbon dioxide, plus very small amounts of other gases. It should probably be noted that the oxygen content of the air in early prehistoric times was probably around 35% -- as proven by analyzing air bubbles trapped in fossilized amber. Nowadays, as I just mentioned, the average oxygen content of air is about 20-21%. However, in some industrial cities with heavy air pollution, the oxygen content may actually run as low as 17%. As a side note, at 15%, life as we know it might conceivably cease to exist. Something to think about…or not. At the very least, it's one more reason to make every attempt to maximise your oxygen intake.



For the most part, this area of respiration is mechanical. Things that can go wrong include, drowning, choking, strangulation, or lack of oxygen in the air -- things mostly outside the scope of alternative therapies and nutrition.



2. External pulmonary respiration

External pulmonary respiration involves the exchange of gases within your lungs -- or more specifically the exchange of gases between the tiny sacs, the alveoli, in your lungs and the blood in your pulmonary capillaries. (This is the primary focus of this newsletter, and we will discuss it in some detail in a moment.)



3. Internal (blood) respiration

Here we're talking about the exchange of gases between the cells in your body and blood in your systemic capillaries. Other than where it takes place, the process is virtually identical to that seen in external pulmonary respiration.



4. Cellular respiration

Cellular respiration involves metabolic processes within the cell. (We will discuss this in a future newsletter that explores cellular biology.)



Movement of gases



As mentioned above, the focus of this newsletter is on the movement of gases in external pulmonary respiration. When we refer to the movement of gases in respiration, we are talking about the exchange of gases in the lungs -- moving carbon dioxide out of the body and oxygen in. In principle, this is remarkably simple and ultimately can be summarized in two words: Boyle's Law. The trick is in getting to that point.



But first, let's take a look at Boyle's Law to see where we're going. Boyle's Law states that for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional (while one increases, the other decreases). Or to phrase it another way, gases flow from an area of high pressure or concentration to an area of low pressure or concentration. Now let's go into the slightly more complicated discussion of how that applies to respiration.



External Pulmonary Respiration



When the mouth and nose are open, the air pressure in the lungs equals the atmospheric pressure in the surrounding environment. The pressure of the space between the visceral and parietal pleura (the sacs that surround the lungs) is only slightly less than the atmospheric pressure -- which keeps them pressed against each other.



When you take in a breath (inspiration), it contracts the diaphragm and increases the diameter of the thoracic cavity, decreasing the pressure between the lung and parietal pleura. In addition, the ribs are lifted up, further increasing the size of the thoracic cavity -- thus lowering the pressure even more. When needed, as when running or exerting yourself, additional muscles such as the external intercostals, the scalenes, and the external oblique abdominals can help pull up the ribs even further providing for an even larger cavity -- and even lowered pressure.



It is the lowering of pressure in the pleura space that draws air into the lungs. A "nature abhors a vacuum" kind of thing. Or to put it another way, air rushes into the lungs to fill the empty space and equalize the pressure.



On expiration, relaxation of the diaphragm causes it to return to its position higher up in the chest cavity, shrinking the size of the cavity, thereby increasing the pressure in the plural space, which expels air from the lungs. And as with inhalation, when needed, other muscles come into play. For example, the internal intercostals and the rectus abdominis muscles (aka the six pack) can help more forcefully shrink the size of the chest cavity, thereby moving air out more completely.



In addition, expansion and contraction of the flexible ribs and the chest can aid in inspiration and expiration.



As we've already mentioned, the accessory muscles of respiration aid in times of pulmonary stress such as during exercise or high stress. Specifically, we're talking about:



~The external intercostal muscles, which connect the ribs and the collarbone and

which pull the ribs up during respiration

~The sternocleidomastoid muscle, which helps raise the first rib, sternum, and

collarbone up by pulling against the head

~The scalene muscles, which also pull the ribs up against the collarbone

~The rectus abdominis and internal intercostal muscles, which pull the ribs down,

collapsing the chest cavity and aiding in expiration



Alveolar capillary air exchange

Once fresh room air has been drawn into the lungs, the exchange of gasses in the alveoli must take place. Each alveolus is lined by a handful of alveolar epithelial cells -- similar to the epithelial cells that line the inside of your mouth and throat. Alveolar epithelial cells are very thin, and as it turns out, the thinnest part of that alveolus cell (the part that does not contain the cell nucleus) rests against the thinnest part of the pulmonary capillary wall -- thus facilitating the diffusion of gas between the capillary and the alveolus. CO2 diffuses out of the blood, across the wall of the pulmonary capillary and then across the alveolus cell wall and into the lung. Likewise, O2 diffuses in the opposite direction to oxygenate the blood. This is the alveolar-capillary exchange, or pulmonary respiration.

As I've already described, pulmonary respiration involves an exchange of gases, swapping oxygen in the alveoli for CO2 in the blood circulating through the pulmonary capillaries and vice versa. Which brings us back to Boyle's Law. The movement of this exchange is dictated by Boyle's Law of Gases, which says that gases move from areas of high pressure or concentration to areas of.... Because the partial pressure or concentration of oxygen is higher in the lungs than in the capillaries, oxygen pushes into the capillaries and is captured by hemoglobin in the blood. Likewise, because the partial pressure or concentration of carbon dioxide is higher in the capillaries than in the lungs, carbon dioxide pushes in the opposite direction through the walls of the pulmonary capillaries and alveoli and into the lungs. That's Boyle's Law.



It should also be noted that carbon dioxide additionally comes from the buffer system in the blood plasma (not only from red cells) that rids the body of excess acid. We talked about this in the last newsletter. It's called the bicarbonate system. The bicarbonate system allows you to add large numbers of CO2 or O2 molecules to the blood without affecting the acidity or alkalinity of the blood to any significant extent. In effect, the bicarbonate system serves as your body's pH buffer system. This is necessary because any change in blood pH beyond 1/10 of a point is potentially lethal. Incidentally, the bicarbonate buffer system also is in play, but to a lesser extent, in body tissue itself. This is why changes in acidity show up in body tissue before they show up in the blood.



Things that can go wrong with respiration



For the most part, unless we're talking about disease states (which we'll do in the next issue of the newsletter), problems that can arise at the physiological level of the respiratory system are mostly mechanical.



Suffocation and obstructions

For example, pulmonary suffocation can result from the closure of the nose and mouth or throat by a foreign body -- resulting in strangulation. Alveolar suffocation, on the other hand, results from water in the alveoli of the lungs preventing the exchange of gasses. Tissue suffocation results from obstructions in the flow of blood through the capillary bed. And cellular suffocation results from metabolic poisons such as rotenone, http://en.wikipedia.org/wiki/Malonate, and cyanide.



Incidentally, cyanide is a particularly effective metabolic poison in that it completely blocks the cell from exchanging gases. Once inhaled or absorbed through the skin, it only takes about seven seconds to reach every single cell in your body. It is particularly insidious in that at the first whiff, it signals the brain that the body is suffocating, which actually forces your body to take a deep breath -- inhaling even more cyanide. The impulse to inhale deeply cannot be resisted by any act of will. Death occurs in about 2-3 breaths. It is so quick acting because it affects virtually every single cell in our body at the same time. Of course, inhaling cyanide is not an issue that most of you are particularly worried about in the course of daily living.



Common clinical obstructions and defense mechanisms

As we've already discussed, at the physiological level, most of the problems you face are mechanical, not nutritional. And since we've already covered the different types of suffocation you might experience, at this point, it is probably worth focusing for a moment on the different locations that obstructions may occur. For example, other than deliberate strangulation or suffocation, there are very few common clinical obstructions of the nose and mouth that can occur and lead to suffocation because of the dual passageways and the ease in clearing them. Further down, in the larynx, the epiglottis prevents food from entering the airway upon swallowing. It can, however, malfunction if one breathes while swallowing (e.g. when talking). Another potential problem is epiglottitis (a viral infection of the epiglottis), which can also very rapidly cause death if it leads to closure of the airway as the result of swelling.



Another defense against suffocation is the involuntary gag reflex, which protects the breathing passage. The gag reflex is triggered in the back of the throat by anything that is not part of a normal swallowing mechanism. When a chunk of food, for example, is transported towards the back of the tongue, its presence usually elicits an automatic series of muscle contractions designed to propel the food on down the esophagus and into the stomach, in effect, completing the interrupted swallow. Efforts at completing the swallow at first increase, and then, if unsuccessful, are converted to attempts to expel the food out through the mouth. And if that doesn't work, retching and finally vomiting are triggered.



Involuntary coughing is another protective mechanism used by the respiratory system to defend itself. If any foreign body makes its way into the trachea and/or lungs, violent spasms of coughing serve to expel the foreign matter. The lungs treat the presence of foreign matter as a serious threat -- which it is. The coughing is triggered by any foreign body (dust, pollen, fluid, etc.) that is not a gas entering the trachea.



It is worth mentioning that alcohol, anesthesia, and other drugs can decrease or even eliminate both the gag and cough reflexes. This is the primary reason you can't eat or drink before surgery. As it turns out, as these reflexes are in the process of being suppressed, the vomiting reflex is automatically triggered. This, of course, is a potential major problem in emergency surgery when the patient may have been eating or drinking shortly before the surgery. It is also a potential problem after drinking heavily or overdosing on sleeping pills. Nausea is triggered as consciousness starts to fade. If there is any food or drink in the stomach, vomiting is likely. At that point, since both the gag and coughing reflex are inhibited, choking on the vomit is a strong possibility -- as many collegiate binge drinkers, unfortunately, can attest to each year. As a side note, once gag and cough reflexes are fully suppressed, the nausea and potential for vomiting go away. It happens only in "transit" as the reflexes are in the process of being suppressed.



A third level of protection is offered by the cilia in the tracheo-bronchial tree. These cilia, or hair-like projections in the cells lining the upper airway beat toward the mouth to remove small foreign material. These cilia are an essential part of the respiratory system's defense mechanisms. Incidentally, cigarette smoking destroys these cilia en masse and in short order. Loss of the cilia harms smokers in three ways:



1. First, cancer causing particles and the secretions that trap them cannot be

cleared

2. Second, because they cannot be cleared, the carcinogens stay in contact with

the lining cells longer

3. And finally, the absence of cilia makes the lungs and cells lining the trachea

bronchial tree that much more vulnerable to other cancer causing pollutants

such as smog



Lung cancer is particularly insidious and has an extremely high fatality rate (about 92% once diagnosed) but is easily preventable. Smoking causes 98% of lung cancer -- with air pollution and radon gas accounting for the rest. The bottom line is that one of the most deadly cancers -- and one of the most prevalent in the world today -- is 99% preventable.



Central control of respiration



Respiration is regulated by the brain, and that regulation is both conscious and unconscious (voluntary and involuntary). In a sense, breathing presents us with the intersection of the conscious and unconscious minds. On the one hand, we can breathe without thinking about it -- even while asleep or unconscious -- and yet, on the other hand, we are fully able to exercise conscious control of our breath. We can control our breathing, speed it up and slow it down and dictate how deep each breath is.



It is interesting to note that the brain's need to breathe is triggered far more by the build-up of carbon dioxide in the blood than by the need for oxygen -- a not so subtle distinction. And in point of fact, this distinction is more than just trivial information. It's why deep sea divers or yogic breathing make use of hyperventilation to drop CO2 levels as low as possible before taking in and holding your breath.



The brain exercises its control of respiration through several distinct centers of respiratory control in your brain, all of which are driven by small changes in blood chemistry. The medullary rhymicity center establishes the basic normal rhythm of 12-15 breaths per minute at rest. (As we mentioned in our last newsletter, the rate of this rhythm can be reprogrammed to a significantly lower rate.) In fact, the medullary rhymicity center actually has separate inspiratory and expiratory centers. And beyond that, a separate center, the apneustic area, controls breath holding. To a large degree, these centers are regulated by changes in the acid alkaline levels of the blood. And as I just mentioned, these centers can be conditioned/trained to alter their normal rhythms. This is a fact of more than passing interest as:



~Rapid breathing and stress are intimately connected.

~Panic attacks and rapid breathing are also closely related.

~Slower breathing lowers blood pressure

~There is an old wisdom that says that every person on earth is given a specific

number of breaths to last their entire life -- or to put it in more practical terms,

the slower you breathe, the longer you live! This is not mere folk wisdom.

Evidence of it is seen throughout the animal kingdom. Animals noted for their

longevity such as the elephant and tortoise have respiratory rates significantly

slower than human beings. The tortoise, for instance, breathes only 4 times per

minute. Tortoises, by the way, can live upwards of 300 years. Animals with fast

breathing rates, on the other hand, such as monkeys (32 times per minute) and

shrews (660 times a minute) have much shorter life spans -- for the shrew,

about 18 months. Efficiency in breathing leads to longer life and better physical

performance. Top athletes understand this principle.

~In yoga, it is said that breath is the cord that ties the soul to the body.



Incidentally, the respiration centers can be depressed or excited by drugs or alcohol -- sometimes with deadly effect. Alcohol is an absolute depressant. Drink enough and you totally shut off the body's breathing mechanisms. As a side note, the "enjoyment" factor of alcohol comes from the fact that the first thing it depresses is your sense of inhibition. As you continue drinking, the effect of the alcohol then goes on to depress every other function in your brain. In cases of binge drinking, after you pass out, the alcohol in your stomach may continue to suppress your breathing to the point where it stops completely and you die in your sleep or suffer irreversible brain damage. Sleeping pills or narcotics can do the same thing. "Party on, dude!"



Physical trauma that can disrupt respiration



There are really only two primary forms of trauma that can disrupt respiration:



Pneumothorax (air in the chest)

Pulmonary edema (fluid in the lungs)



Pneumothorax

If air enters the pleural space between the lung and the chest wall, it causes a loss of the vacuum that, as we've already discussed, is necessary for respiration. Where does that air come from? Ninety percent of the time, it comes from outside the chest (e.g. through a hole in the chest wall -- gun, knife, etc.) or from the inside if the wound penetrates far enough (e.g. a hole in the lung caused by that same gun or knife). Without a vacuum to hold the lung against the chest wall, the lung collapses (partially or completely), which prevents any gas exchange on that side of the chest. Treatment involves the insertion of a chest tube and suction to recreate the vacuum, then stapling the hole closed. Treating a hole in the chest wall is much easier than treating a hole in the lung. As I mentioned, the primary cause of pneumothorax is external trauma (guns, knives, automobiles, etc.). But on some occasions, holes can be caused by internal conditions such as a spontaneous pneumothorax, a ruptured bleb (an air or fluid filled sac caused by emphysema), or hyperinflation of the lung during anesthesia.



Pulmonary edema (fluid in the lungs)

This is an internal condition, also known as cardiogenic edema , which is caused by failure of the left heart, which causes blood to back up into the lungs. As we discussed in our series on the cardiovascular system, right heart failure causes edema to the body (blood returning to the heart from the body enters through the right atrium). But in pulmonary edema, if the left heart is not pumping out blood as fast as it's receiving it from the lungs (blood from the lungs reenters the heart through the left atrium), the blood will back up into the lungs. And since it's under pressure, it will seep into the alveoli and the spaces between the alveoli and fill them with fluid. If not treated immediately, the patient will literally drown in their own blood.



Safeguarding your respiratory system



That concludes our discussion of the physiology of the respiratory system. In the next part of this series, we'll discuss the diseases of the respiratory system; but before we conclude this issue, let's briefly talk about some of the things you can do to protect the physiological functions of your respiratory system. And other than the obvious things such as avoiding getting stabbed, shot, or being in an automobile accident, you might want to consider:



~Quitting smoking. 1.2 billion people smoke worldwide-- some 43 million in the

United States alone. There isn't much you can say good about smoking. As

we've already seen, it destroys all of the cilia in your trachea bronchial tree. It is

the primary cause of lung cancer and emphysema (which we will talk more

about next newsletter). And it's harmful to everyone around you --

even weeks after you finish your cigarette.

~You might want to consider investing in a high quality air filtration system (and

no, the Ionic Breeze does not count). The IQAire Health Plus is highly regarded

-- and is priced accordingly.

~Supplement with a good proteolytic enzyme formula to help thin mucous, reduce

Consider incorporating nasal irrigation into your daily routine to optimize the flow

of air through your nasal passages. inflammation in the lungs, and reduce the

chances of embolisms in your lungs.

~Consider incorporating nasal irrigation into your daily routine to optimize the flow

of air through your nasal passages.

~As we discussed last issue, practice breathing exercises to optimize the

efficiency of your lungs.

~And maybe consider that move to Tasmania after all. Or if you don't want to live

down under, you can check this list of the places that have the world's cleanest

air.

~Oh, and learn the Heimlich maneuver in case of emergencies.

That's it for now. In our next issue, we'll conclude our series on the respiratory system by discussing the diseases that can affect your ability to breathe such as COPD, Emphysema, Asthma, Allergies, Bronchitis and flu, Bird flu, Pneumonia, Cystic fibrosis, Pulmonary fibrosis, and Pulmonary embolism.



For more information on the Respiratory System:



Part 1, The Anatomy of the Respiratory System





Jon Barron's Alternative Health Newsletter

http://www.jonbarron.org/

Copyright © 2002-2009 The Baseline of Health Foundation. All rights reserved.

Baseline of Health® is a Registered Trademark of Jon Barron