The lungs are the main respiratory organs. They fill the entire chest cavity with the exception of the mediastinum. Next, we consider the main tasks of these bodies. The article will also describe the lobes and segments of the lungs.
Functions
In the lungs, gas exchange occurs. This process is the absorption of oxygen from the alveoli of oxygen by blood red blood cells and the release of carbon dioxide, which decomposes in the lumen into water and gas. So, in the lungs there is a fairly close union of nerves, lymphatic and blood vessels, as well as the airways. The latter begins with the early stages of phylogenetic and embryonic development.
The level of oxygen supply depends on the degree of ventilation, as well as on the intensity of blood flow, the diffuse velocity of gases through the alveolar-capillary membrane, the elasticity and thickness of the elastic frame, saturation with hemoglobin, and other factors. When a single parameter changes, a violation of the physiology of respiration occurs and a number of functional disorders can occur.
Departments: general information
Segments of the human lungs are areas of the parenchyma. They include the artery and bronchus. At the periphery, the elements are fused. Unlike pulmonary lobules, the junction areas do not hold clear connective tissue layers. Each element is presented in the form of a cone. The top is directed to the gate of the lung, the base - to the surface. Branches of veins lie at the joints. There are nine segments in the left lung. In the neighboring organ there are 10 parts. The left lung includes two lobes. The right consists of three parts. In this regard, their internal structure is somewhat different. To the left, 4 segments are distinguished in the lower lobe. These include:
- Lower back.
- Lower outdoor.
- Lower Inner.
- Upper.
There are also reed segments of the lungs:
In the lower part of the left side, it is considered more correct to distinguish four segments. This is due to the fact that the lower front and inner departments include a common bronchus.
Right lung segments: posterior
This site is located dorsally from the apical. There are 5 borders in a segment. Two of them are projected between the apical, superior and posterior on the medial surface. Three borders are on the costal surface. The jumper, which is formed by the anterior and posterior segments of the lung, has a vertical orientation. To the vein, artery and bronchus of the posterior element is carried out from the medial side in the dissection of the pleura of the gate surface or from the initial section of the horizontal groove. Segmental bronchus is located between the vein and artery. The blood channel of the posterior element is connected to the anterior vessel. Together they enter the pulmonary vein. Between the II and IV costal plates, the posterior segment is projected onto the surface of the sternum.
Front zone
This segment is located in the upper lobe. It can have five borders. Two lie on the medial surface. They separate the apical and anterior, anterior and medial segments of the lung. Three boundaries lie along the surface of the ribs. They divide the medial, anterior and lateral, posterior and anterior, apical and anterior segments. Artery departs from the upper main branch. Deeper than the bronchus is a vein. It is presented as an inflow from the upper branch. The bronchus and vessels in the segment when dissecting the medial pleura can be bandaged in front of the gate. The front zone is located in the region of II-IV ribs.
Lateral division
This segment is projected from the medial part only as a narrow strip lying above the interlobar oblique groove. The bronchus has an orientation back. In this regard, the segment is located on the back in the middle lobe. It is viewed from the side of the surface of the ribs. There are five borders in the department. Two of them lie along the medial surface, separating the anterior and lateral, lateral and medial segments of the lung. The first boundary lies in accordance with the final section of the oblique groove. The other three are located on the costal surface of the organ. They separate the medial and lateral segments of the lung of the middle part.
The first border runs vertically. It goes from the center of the horizontal furrow to the edge of the oblique. The second border runs between the anterior and lateral segments. It corresponds to the location of the horizontal furrow. The third border is in contact with the posterior and anterior segments in the lower lobe. Vein, artery and bronchus are deep. Approach to them is possible only below the gate along an oblique furrow. The lateral segment is located in the area between the IV-VI ribs.
Medial department
It is visible both on the medial and on the costal surfaces in the middle lobe. There are four borders in the department. Two separate the medial area from the lateral in the lower and anterior in the upper lobes. The second boundary coincides with a slanting furrow. The first one runs along the front of the horizontal recess, respectively. Two edges also pass along the costal surface. One starts from the middle of the anterior zone of the horizontal furrow, descending to the end of the oblique. The second border of the anterior segment is separated from the medial. The line coincides with the location of the horizontal furrow. A segmental branch departs from the lower branch of the artery. Under it is a bronchus and a centimeter vein. The approach to the segmental leg is carried out from the bottom of the gate through the interlobar oblique groove. The border on the chest is located in the region of IV-VI ribs in the axillary midline.
Upper Bottom
This segment is at the top. In the region of III-VII ribs in the area runs two boundaries. One passes between the upper section in the lower and posterior segments in the upper lobe. The border runs along an oblique groove. The second line goes to the upper and lower segments of the lower part. To determine the boundaries, you should approximately continue the front region of the horizontal furrow from the place of its connection with the scythe. An artery of the lower branch of a common vessel fits into the upper segment. Below it is the bronchus, then - Vienna. Access to the gate is possible through a slanting interlobar sulcus.
Medial Basal Division
This segment is located on the medial side below the pulmonary portal. The department is in contact with the vena cava inferior and the right atrium. The segment is separated by a border from the posterior, lateral and anterior. A vessel departs from the lower branch of the artery into the department. The highest part of the lower lobe bronchus is considered segmental bronchus. Below it is a vein that flows into the lower right side of the main.
Front Basal Division
This segment is located in the lower lobe, its anterior section. On the sternum, its location corresponds to the VI-VIII ribs of the axillary midline. There are three borders in the department. The first line runs between the lateral and anterior segments in the middle lobe. It corresponds to a slanting furrow. The projection of the second border coincides on the medial surface with the beginning of the ligament. The third line runs between the upper and anterior segments. The artery starts from the lower branch of the common arterial canal. The bronchus departs from the process of the lower lobe of the same name element. A vein enters the lower main venous branch. The bronchus and artery are visible at the bottom of the oblique groove under the visceral pleura. A vein is found under the ligament.
Basal Lateral
This segment is visible on the diaphragmatic and costal sides of the lung. There is a division in the area between the VII-IX plates along the axillary back line. It has three boundaries. The first passes between the anterior and lateral segments. The last and medial divisions are shared by the second border. The third line runs between the posterior and lateral segments. The bronchus and artery lie along the bottom of the oblique groove, the vein - under the ligament.
Basal posterior region
This segment is located in the lower lobe. It is in contact with the spine. The segment occupies a space in the region of VII-X ribs. There are two borders in the department. They separate the posterior segment from the superior and lateral. Vein, bronchus and artery lie along the depth of the oblique groove. With surgery, they are best accessible from the medial side of the lower lobe.
Segments of the left lung
In the upper part there are the following departments:
- Apical. It almost repeats the shape of the segment of the same name in the right lung. Vienna, bronchus and artery are located above the gate.
- Rear. Its lower border goes down to the V rib. The posterior and apical segments of the left lung are often combined into one.
- Front. Its lower boundary lies horizontally relative to the III rib.
Reed segments of the left lung:
- Front. It is located on the costal and medial sides in the region of III-V ribs and along the median axillary line at the level of IV-VI plates.
- Lower. It is located under the previous department. Its border coincides with the furrow. The lower and upper reed segments of the lungs are separated in the middle by the center of the cardiac notch.
The departments of the lower part coincide with those in the opposite organ.
Surgery: indications
In case of violations of the functions of any site, its resection (removal) is carried out. Such a need may arise in the following cases:
- Destruction of tissues against the background of inflammation provoked by infection (tuberculosis, most often).
- The degeneration of the lung in the process of tumor growth (evil and benign).
- Acquired or congenital formation of a hollow area.
- Purulent tissue decay against the background of a number of pathologies.
- Injuries.
Operation progress
As a rule, it is typical. Since the lungs are hidden in the sternum, an incision is made between the ribs for better access to them. Then the plates are pushed apart using a special tool. In accordance with the size of the affected area, a resection of the anatomical and functional element is performed. For example, a segment of the lung may be removed. In various combinations of resection, several departments can undergo at once.
Lobectomy may also be performed . This intervention involves the removal of an organ lobe. In rare cases, an edge resection is performed. This operation is atypical. It is the suturing and removal of the damaged area on the outside of the lung. As a rule, this type of resection is performed for injuries characterized by a small amount of damage.