Your lungs are really incredible. A professor of anatomy explains why

The lungs are remarkable organs that continually perform incredible feats. They do it so well that we take it for granted, except when their function is diminished. Everything happens in a space inside your breast divided in two and reduced by the presence of heart, large vessels and esophagus.

Supreme Court Judge Ruth Bader Ginsburg recently returned to court after a lung cancer operation, so I asked a lot of questions about the lungs because I am an anatomy professor.

Many lung cancers are not operative, but to treat certain types of lung disease, such as the early stages of lung cancer, a surgical treatment called lobectomy can be performed. In this operation, a lung lobe (your right lung has three lobes, your left lung has two) is removed. Then the other lobes expand to fit and compensate for the missing tissue, allowing the lungs to function as well or better than before.

In addition to being very effective organs, the lungs have a complex and beautiful structure. I can not help but wonder if we appreciate them more, would we be more proactive in caring for them?

Breath of life

The primary function of the respiratory system is to bring oxygen into our lungs. There, it is exchanged for a waste, the carbon dioxide, which is then eliminated from the body.

Several weeks after conception, the work of the lungs is performed by the placenta, a structure located outside our fetal body where our blood exchanges carbon dioxide and oxygen with the mother's bloodstream. 39; uterus.

Before birth, we simply practice breathing movements, moving the amniotic fluid instead of air into and out of the lungs.

A few seconds after cutting the umbilical cord, an accumulation of carbon dioxide causes the asphyxia of newborns and the exchange for oxygen, an activity that will continue until our death. The average person breathes about 13 million cubic feet of air during his lifetime.

During a quiet activity, such as in bed or sitting, we take 8 to 16 breaths per minute, each breath inhaling about a quart of air containing 21% oxygen and a small amount of carbon dioxide for about two seconds. Then, for three seconds, we exhale the same amount of air, but it now contains 16% oxygen and a 100-fold increase in carbon dioxide. In other words, you spend about 40% of your life sucking in air and 60% expelling it.

Your lungs, in numbers

Every day, 5,000 gallons of air are transported through the airways to and through the lungs. The airways branch out and decrease in size 22 times. Almost all of this occurs in our lungs, these airways reaching a total length of 14,900 miles.

Approximately 2600 gallons of transported air is routed to and removed from 300 million tiny hollow-walled or thin-walled bags that provide a huge surface for the exchange of oxygen needed by all our cells for carbon dioxide. , a piece of trash. product of them. This is an area that varies in size from half to most regulated tennis courts.

This huge space is contained in two lungs, each slightly smaller than three 1-liter bottles. The left lung is 10% smaller than the right, because of the position of the heart on the left side.

The alveoli are closely surrounded by blood vessels, or capillaries, so small that the red blood cells pass continuously through them in a single row when they exchange carbon dioxide with oxygen.

The capillaries of the lungs receive an immense blood supply, equal to that distributed to all the other parts of the body. The cells enlarge and contract 15,000 times a day. During physical activity, the breathing rate doubles – and in extreme activities, triple -, and the amount of air reaching the alveoli increases three to five times. Breathing deeper and faster uses the lung capacity kept in reserve at rest. Stress can also lead to deeper and faster breathing.

Your lungs at work

However, the air we breathe is far from pure and one of the main tasks of the respiratory system is to "condition" the air before it "n". reach the air sacs deep in your lungs.

Indoor air pollutants can have two to five times more pollutants than outside air. (Have you recently observed and changed the filters in your heating / air conditioning system?)

The respiratory system "conditions" the air in many ways. First of all, it increases the temperature of the cold air compared to the body temperature or cools the warm air to the body temperature. Second, it hydrates the air to 100% moisture to prevent dehydration of the alveolar membranes. Finally, it cleans the air.

Foreign and potentially harmful substances are filtered from the incoming air and eliminated by several means, including nasal hair and sticky mucus lining the airways, which are produced at a rate of approximately one quarter per day. . It contains antimicrobial agents that help neutralize harmful germs and many viruses.

It is important to note that hair-like projections on the cells lining the airways, called eyelashes, cause the soiled mucus to come out of the lungs and the airways to the throat to be swallowed and destroyed by stomach acid. .

Pollutants that reach the alveolar gas exchange membranes are removed by specialized cells called phagocytes and macrophages that ingest the particles that move the most to be washed away by the vessels and lymph nodes. However, much of the black carbon is simply displaced to parts of the lung that are not exchanged.

In addition to air conditioning for the alveoli, lung ventilation helps cool the body when it is overheated. About 7% of body heat is removed by evaporation from the airways in and around the lungs. Eleven ounces of water a day are lost as water vapor. Three percent of body heat is lost by heating air below body temperature when ventilating the lungs.

Other amazing functions of the lungs include controlling the acid-base balance (pH) of the body as a whole by selectively retaining or eliminating carbon dioxide. In order to be broken down for gas exchange, the lungs act as a bellows. The propulsion of air from the lungs allows the larynx to serve as a "voice box", vibrating the vocal cords to produce the tone modified by the tongue, teeth and lips to produce our voice for communication interpersonal and for singing. This air outlet also allows us to blow up balloons or play wind instruments.

The air sucked by the expansion of the lungs passes on the olfactory areas of the nose, thus allowing our sense of smell. The lungs also act as a "packing foam" inside the rib cage, supporting and protecting the vital heart that delivers half of its flow to the lungs and the other half to the rest of the body.

The dark side of the lungs and their care

While the lungs were a pristine pink at birth, our lungs gradually darken to give a gray, mottled appearance because of these carbon particles, much of which remains in place, usually with no effect harmful. Larger and more irritating particles are usually eliminated by coughing and reflex sneezing. This air conditioning system is compromised in smokers, whose airways lose their eyelashes and directional coordination, and must therefore return to cough as a major means of eliminating pollutants.

Smokers' lungs darken faster, become more mottled, and take on an orange hue due to nicotine and brown tars. Prolonged exposure to these carcinogens causes chronic bronchitis, emphysema, and cancer in many parts of the body, but especially around the airways just at the entrance of the lungs. In emphysema, the alveolar structure of the lungs will collapse, especially in the upper lungs, making it difficult to complete expiration.

Take a deep breath and consider all the miraculous activities that your unbelievable lungs perform.