Pulmonar

Pulmonar

For other uses of this term, see Lung (disambiguation) .

Lung
Human lungs
Pig lungs
Latin	[ TA ] lungs
TA	A06.5.01.001
System	Respiratory
Artery	Right pulmonary artery or left
Come at	Pulmonary vein left or right
external links
MeSH	A04.411
FMA	68877
[ edit data in Wikidata ]

The lungs are anatomical structures of human embryonic endodermal origin, belonging to the respiratory tract , are located in the chest , delimiting on both sides the mediastinum. Its dimensions vary, the right lung is larger than its left counterpart (because of the space occupied by the heart ). They have three faces; mediastinal, and diaphragmatic rib, which supply the bronchial arteries and pulmonary arteries carry blood him for oxygenation.

The lungs are the organs in which the blood receives oxygen from the air and in turn follows from the blood carbon dioxide which enters the air.This exchange occurs by diffusion of oxygen and carbon dioxide between the blood and alveoli forming lungs. The lung function is gas exchange with the blood, so the cells are in close contact with capillaries. In the alveoli step produces oxygen from the air to the blood and the passage of carbon dioxide from the blood into the air. This step occurs by the difference of partial pressures of oxygen and carbon (simple diffusion) between blood and alveoli dioxide.

Anatomy and features [ edit ]

Sample cut lung, in which you can appreciate its texture and shape and may even see the alveoli.

1: Trachea 2: Pulmonary artery 3: Pulmonary Vein 4: terminal bronchiole 5: hexagonal 6: cardiac Court 7: tertiary or segmental bronchi 8: 9 lobales side or bronchi: main bronchus 10: traquial Fork or carina 11: Larynx

The lungs are located inside the chest, protected by the ribsand sides of the heart .They are hollow and are covered by a lubricated double membrane (serosa) called pleura . They are separated from each other by themediastinum .

The pleura is amembrane ofconnective tissue , elastic that prevents the lungs from rubbing directly with the inner wall of the rib cage. It has two layers, the parietal pleura or outer covering and the diaphragm and the inside of the rib cage, and the visceral pleura covering the outside of the lungs, introducing in its lobes through fissures adheres. Between the two layers there is a small amount (about 15 cm³) of liquid lubricant called pleural fluid .

The surface of the lungs is pink in children and irregularly distributed dark areas but some uniformity in adults. This is called antracosis and pathological character appears, showing almost all the inhabitants of cities, as a result of inhalation of dust floating in the air we breathe, mainly coal.

The weight of the lungs depends on gender and thorax they occupy: The right lung weighs 600 grams on average and the left reaches on average 500 g. These figures are slightly lower for women (due to the smaller size of the rib cage) and somewhat higher in men. ¹ The right lung is divided by two fissures (horizontal and oblique) in 3 parts, called lobes ( upper, middle and lower). The left lung has two lobes (upper and lower) separated by a fissure (oblique). This is because the heart has an oblique slant to the left and back to front; "Digging" the lower tip (apex) in the left lung, reducing its volume and removing said lung space. A vertex or apex (corresponding to its top, which exceeds the height of the lungs are described in both clavicles ), and a base (bottom) that rests on the muscle diaphragm . The major fissure of both lungs is from the 4th intercostal space posterior to the anterior third of corresponding hemidiaphragm. In the right lung separates the upper and middle lobes lower lobe, while the left lung separates only two lobes: upper and lower. The minor fissure separates the upper and middle lobes of the right lung and runs from the anterior chest wall to the major fissure. It may be absent or incomplete in up to 25% of people. In each lobe they distinguish different segments , distinct, corresponding to each a bronchus segmental (bronchial 3rd generation). There are several classifications to name the different segments, one of the most accepted the Boyden. ² The segmental bronchi are subdivided into themselves bronchi and bronchioles (12-16 generations). The latter lack of cartilage and branch into terminal bronchioles and respiratory bronchioles (17-19 generations) that flow into the alveoli : the functioning of gas exchange units of the lung.

Front view of both lungs open a dissection plane to display fissures, lobes and airways: trachea and bronchial tree.

The mucosa of the respiratory tract is covered with millions of tiny hairs, or cilia whose function is to trap and remove any dust and germs suspended from breathing, avoiding, if possible, any entry of solids that cause aspiration .

The lungs are about 500 million alveoli, forming a total area of about 140 m² in adults (approximately half the area of a tennis court ) (56 m² according to another source). ³ Lung capacity depends on age , weight and sex; between 4000-6000 cm³. Women often have half a forced inspiratory volume of 1.25 liters less than men. ⁴

Function [ edit ]

The lungs have a respiratory function and other non-respiratory:

Respiratory [ edit ]

The lung function is gas exchange with blood , it is because of this that the cells are in close contact with capillaries. In the alveoli it occurs passing oxygen from the air to the blood and the passage of carbon dioxide from the blood into the air. This step occurs by the difference of partial pressures of oxygen andcarbon dioxide (simple diffusion) between blood and alveoli.

In the alveoli oxygen concentration it is so high that the oxygen passes through the alveolar membrane and into the pulmonary blood capillaries; while the pulmonary capillary hemoglobin of the red cells of the blood are linked in as many molecules of carbon dioxide and lesser amounts of oxygen . In the sector of the pulmonary capillaries surrounding the alveoli gas exchange occurs oxygen for carbon dioxide , in which the hemoglobin molecule to release carbon dioxide and take in oxygen. Furthermore there blood carbon dioxide from bicarbonate dissolved in the pulmonary capillary blood.

All body cells use this oxygen for oxidation of glucose thereby generating the energy required for each continue operating.Oxidation occurs in an organelle called mitochondria of cells where it is generated as a byproduct carbon dioxide. ⁵

Functional Anatomy [ edit ]

The mammalian lung consists of many adjacent full air sacs called alveoli. Are interconnected with one another by so-calledpores Kohn , that enable movement, important for the distribution of gas air side. The airways of the lung which are not involved in respiratory function, are formed by smooth muscle and cartilage. The epithelium is ciliated and secretes a mucus which climbs up the airway and maintains the entire system clean.

The respiration process occurs in the lungs gases through a diffusion barrier formed on the mammalian surface by an aqueous film, the epithelial cells that form the socket wall, the interstitial layer, endothelial cells of blood vessels , plasma and the membrane of the red blood cell that captures or releases the gas. There are different types of cells in the respiratory epithelium. Thus, type I cells are the most abundant form the wall between two alveoli and have a cornered core at one end. Type II cells are less abundant, and are mainly characterized by the presence of a laminar body inside, also they have villi on its surface; producing cells are surfactants. Surfactants are lipoprotein complexes which provide very low surface tension at the liquid-water interface, thereby reducing the need for stretching the pulmonary wall tension reduction work, and in turn preventing the collapse of alveoli. Type III cells are less abundant and have many mitochondria and brush border. There are also in the respiratory epithelium macrophages alveolar.

Respiratory [ edit ]

• Action external filter. The lungs are defended by the intense air pollution to which they are exposed by the action of system mucociliary and fagocitario of macrophages alveolar .

- The production of mucus impacting particles of a certain size and is produced by cells in the glands seromucousbronchial and goblet cells of the epithelium bronchial.

• System anti- protease mainly α ₁ -antitrypsin happens in the alveoli to elements inflammatory 's immune systemalveolar. Major proteases in the lung are elastase , collagenase , hyaluronidase and trypsin .
• Metabolic actions:
  • Participation hormone of the renin-angiotensin-aldosterone system
  • Elimination of drugs
  • Acid-base balance
  • Metabolism lipid per share of pulmonary surfactant
• System prostaglandins which cause bronchodilation ( Prostaglandin E ) or bronchoconstriction ( prostaglandin F , A , Band D )

Circulation [ edit ]

The system that supplies blood to the lungs ( pulmonary arteries and their branches) follows a parallel path airway, while the venous system is more variable and can be arranged in different paths. In the right lung, the pulmonary vein draining the upper and upper middle lobe and inferior pulmonary vein draining the lower lobe. In the left lung pulmonary vein draining each lobe of the same name. Keep in mind that the pulmonary circulation has a peculiarity with the rest of the systemic circulation as the pulmonary arteries contribute little oxygenated blood from the ventricle right, while the pulmonary veins, after gas exchange in the alveoli, provide oxygenated blood into the left atrium. The exchange of oxygen and carbon dioxide takes place by diffusion.

Diseases and problems [ edit ]

Image showing a lung affected with cancer.

They can be present from birth (such as bronchopulmonary sequestration ), developed along life or after suffering an accident . The most common causes of lung diseases tend to develop ⁶ are inhaling gases, smoke , dust and chemicals. Among the highlights lung lesions of inflammatory nature, secondary to an infectious germ. Some prominent diseases ⁷ are:

• Bronchitis : When inflammation occurs only in air ducts caliber.
• Pneumonia : The inflamed area is a lobe.
• Bronchopneumonia : The inflamed area affects the territory of several lobes.
• Emphysema : Chronic Disease ⁸ characterized by the permanent enlargement of the airspaces distal to the bronchioles respiratory, destruction of the wall withalveolar , with or without fibrosis manifest.
• Pneumothorax : This is caused by the rupture of the pleura , air entering the pleural space and causing a collapsed lung. Symptoms include acute chest pain, cyanosis, shortness of breath, among others.
• Fibrosing alveolitis : A disease that causes scarring and thickening of the alveoli . It is of unknown cause, and in some cases next to diseases such as rheumatoid arthritis
• Asbestosis : It is an irreversible disease caused by prolonged inhalation of asbestos . After inhalation , the asbestos is set in the lungs, causing scarring and thickening of the pleura . so the lungs do not expand and contract normally.
• TB : This is a contagious disease that is usually spread by air. For many years he has been the most serious disease of mankind.
• Lung Cancer : It is one of the diseases most serious and one of the cancers with the highest incidence in humans.Although commonly tend to use the term "lung cancer" generically, it is important to point out that there is no single type of the disease. Depending on the appearance of cancer cells, and distinguish between the microcrítico lung cancerand lung cancer microcrítico not. The former also called cancer cells oat, avenoides carcinoma cells or small cell undifferentiated carcinoma. Their incidence rate represents 10 to 15% of all lung cancers diagnosed. The microcrítico not divided, in turn, in adenocarcinoma, squamous cell carcinoma and large cell carcinoma.

Besides the above two, they can register other tumors in the lungs. Such, for example, carcinoid tumors (around 5% of registered cases), chemical adenoid carcinomas, hamartomas, lymphomas and sarcomas. The snuff is the most important risk factor when suffering from lung cancer, encouraging up to 80% of deaths from this disease . Although lung cancer is not the only condition in which the smoking acts as a trigger, ⁹ is definitely the highest incidence. Contrary to popular opinion, all types of snuff are equally pernicious. Continued exposure to smoke or secondhand smoke environmental snuff ( smokers liabilities) is also key when it comes to developing lung cancer.

• The pneumonia and bronchopneumonia have been for many centuries the cause of death greatest among children and the elderly, appearing from the outset as a complication of another disease. At present they are statistically a very serious problem, and much of the senile mortality is due to it. Bronchopneumonia, tuberculosis and lung cancer are the most prominent lung diseases.

Examination by percussion [ edit ]

Percussion different levels in a patient with lower respiratory tract disease pathology show the status of the patient where

• N: 0 is completely healthy, no pathology
• N: 1 corresponds to a bronchopneumonia or bronchitis, it's a condition with inflammation of the bronchial tree level
• N: 2 patient presents with pneumonia here as shown in Figure 1.1 can be seen that both the amount of air as the degree of injury are 50%
• N: 3 we find conditions such as edema and acute pulmonary is serious this situation can happen for the next level and a patient may die
• N: 4 is a lung collapse and ensuing death of the patient, both the degree of injury and the amount of air are killed and is no longer compatible with life, as it generates hypoxia within the cells causing irreversible damage to these

Note that you must evaluate the patient, and this may go up or down according to their level of development or exacerbation in the pathology diagnosis

Transplantation [ edit ]

Lung transplantation is one of the last alternatives in case of lung failure. The donor lung is obtained from a person he declared brain dead, but remains on life support. Tissues should be as compliant as possible so that there is no rejection.The first experimental lung transplants were dogs, sheep and monkeys between 1947 and 1950. The first transplant carried a person was in 1963. ^{[ citation needed ]}

Comparative animal biology [ edit ]

Source [ edit ]

The "lungs" invertebrates are not homologous to the lungs of vertebrates, since they are formed by invagination ofectoderm . One example is the quelicerados ( sea spider , sea scorpion ), and gastropods lungfish ( snail ) where is the mantle cavity which plays the role of lung, communicating with the outside through a small hole called pneumostoma. In general, the lungs allow breathing in an air medium, preventing dehydration .

The lung of vertebrates has its embryological origin in a fold of the esophagus . Therefore consists of endoderm , mesoderm secondarily bent for vascularization. All chordates have at some point in their "life cycle pharynx perforated "(faringotremia or gill slits) that emerged in the Prochordates as a filter-feeding mechanism. The system operates by introducing water with food particles, which remain stuck to the wall of the pharynx by mucus, while the water back out by the pharyngeal slits. Over the protovertebrados of life filtering system to another predator, the pharynx was modified as a muscular power apparatus, through which could pump water expanding and contracting the cavity. In fish it has inherited this perforated pharynx but no longer used for food and pharyngeal walls are at the gills.

Evolution and specialization [ edit ]

In the animal world, the lungs are structures specially adapted to terrestrial environment and air breathing. Its function is to store air to filter and absorb oxygen. The lungs are most partitions or septa which produce more gas exchange surface and greater efficiency. Fish gills, spend 20% of energy in breathing while birds and mammals only 2%. It should be noted that the metabolism of birds and mammals is much higher, needing to feed more often.

Fish and amphibians . They perform gas exchange through the skin, lungs and oropharynx. Lungfish has a unique lung and amphibians and just two small lungs are sac, so they are not very efficient. Depending on the species and their evolutionary level, ranging from a simple smooth-walled sacks in urodele, the divided into several chambers of frogs. These lungs are a number of cameras that are called "faveolos". Introducing air into the lungs overpressure what differentiates them from birds, mammals and reptiles that make for depression. However, the skin is the main respiratory organ due to its large surface area and allowing them to breathe while remaining partially wet or are submerged. Amphibian tadpoles because of its aquatic life, have 3 pairs of gills protruding from the body.

In all reptiles breathing is lung. His lungs have partitions or septa, which offer greater gas exchange surface and increased efficiency. The total area of gas exchange is greatly increased compared to amphibians. The serpents (snakes), are elongated and functional atrophied right lung and left lung. Sea turtles in addition to pulmonary respiration, have cloacal breathing, take their vascularized cloaca O ₂ dissolved in water.

The birds use their two small lungs like bellows which blow air into them (for depression) and air sacs. These air bags are large bags filled with air and connected to the lungs. The air sacs are distributed among the viscera of the animal and even extend inside the bones. The wall of the bags is not vascularized and it is not where the exchange occurs, it only occurs in the lungs, but in some quantity, oxygenated air is diffused by the body, as in birds and mammals by skin. Poultry have no lungs or alveoli faveolos but a series of parallel tubes together called "para-bronchi". Pulmonary efficiency is much higher than in other animals because the air flow is unidirectional and is not a volume of residual air. Each cycle consists of two inhalations and two breaths. The air sacs are connected to the lungs so that about 75% of the inspired air passes through these long and flows directly into the subsequent bags. serving as a reservoir of fresh air. On the exhale the fresh air of post bags is channeled through the lungs and incorporated above air sacs. Of these flows directly outside. The advantage of such an arrangement is that the lungs oxygenated air is always going in both expiration and inspiration like. The inhaled air is taken through the trachea to the bronchi , and then to the lungs, where the parabronchi with hematosis capillaries, which carry gas exchange in the inspiration and exhalation. Air sac also act as coolants, lowering excessive body heat. In terms of the division of the trachea, bronchi lies a vocal organ called syrinx, which performs the function of singing.

All mammals, including water, are air-breathing. They are characterized by two well-developed lungs and divided into lobes. The lungs are housed in the pleural cavity, limited by the diaphragm, a muscle with your relaxation and contraction, makes the entry and exit of gases. The airways are the trachea divides into two bronchi to each lung. These are followed ends bifurcating in bronchioles and alveoli, the rest of animals are called faveolos. Gas exchange (hematosis) takes place in the alveoli. The alveoli are blind sacs that are surrounded by capillaries. The sound emission is made ​​possible by the presence of vocal cords in the larynx . Between a mammal and an amphibian of equal size the first has 10 times more lung surface.