Where does hypertension come from? We check the kidneys and treat snoring. Negative pressure Pressure positive and negative

Oddly enough frequent cause Secondary hypertension becomes snoring. True, not a simple snoring, but snoring with a stop of breathing. Everyone knows such people: they snore-snoring, and then their breathing stops. Silence lasts a few seconds, and again a man walked. So, this is not just a bad habit, but a symptom of a very serious illness, which is called "obstructive sleep apnea syndrome."

What is apnea? It is a Greek "Stop breathing." The walls of the upper respiratory tract are falling down, breathing stops, the brain does not get oxygen, and the person wakes up. Wakes up for "enable" respiratory center, start breathing again. Most often, he wakes up not to the end and in the morning I will not remember about my microprobrogs, but such a torn sleep with a violation of the blood supply of the brain becomes the reason for the increase in pressure and heart rate violations, up to life-degraded arrhythmias. In the morning these people wake up non-wisp, the afternoon, they clone into sleep, they often fall asleep in in public places And even driving.

Please remember: if you or your close person Sourling is a reason to attract the attention of the doctor to this problem. These patients perform a special study - during sleep, the main life indicators are recorded: the respiratory rate, pulse, heart rhythm, the muscular movement of the larynx wall, which are responsible for the snoring, blood saturation with oxygen. And if there is a lot of episodes of stopping the breath, then the doctor can recommend using a special device called sipap.

Translated from English this "constant positive air pressure in respiratory tract" The special treadmother is put on the bedside table, put on a mask on the face, and the patient with this mask sleeps all night. The air "breaks through" the respiratory tract, as a result of which the snoring and stopping of breathing disappears, and the pressure is often normalized or the severity of hypertension is significantly reduced. But with this mask you will need to sleep the rest of my life.

Renal hypertension

Kidney - one of of the most important organs Arterial pressure regulators. Accordingly, some chronic diseases accompanied by kidney damage, such as diabetes, Gong, glomerulonephritis, can lead to an increase in pressure.

Another reason for the "renal hypertension" is a narrowing (stenosis) of the renal arteries. In order for the kidney normally, a sufficient amount of blood should come to them. Sometimes against the background of heavy atherosclerosis in renal arteries, an atherosclerotic plaque appears from one or two sides, which narrows the lumen of the renal artery. Kidneys say they lack oxygen, and believe that pressure in blood system It fell, which means it should be increased. The body with the help of special mechanisms increases pressure, but the intelligence of the renal artery as it was narrow and remained. The kidneys say again that they lack blood flow. And this vicious circle closes.

This is one of the most severe forms of hypertension. Pressure, especially diastolic, decreases very badly. Stenosis of the renal arteries most often happens in the elderly smokers, since it is smoking that is the most powerful stimulator of atherosclerosis.

If your hypertension becomes heavier, ceases to succumb to therapy, then it is necessary to go to the doctor and find out whether the stenosis of the renal arteries has not developed. To identify this disease make an ultrasound study, and better - computer tomography renal arteries. Sometimes, for the treatment of such hypertension, the vessel is put a stent - a special metal "spring", which restores the clearance of the vessel.

Endocrine (hormonal) hypertension

Sometimes the pressure increases is associated with an excess of some hormones. One of the most frequent endocrine diseases is a disease, thyrotoxicosis. To recognize it, spend a study of thyrotropic hormone (TSH) in the blood. The deviation of the level of TSH unequivocally indicates pathology thyroid gland.

By the way, in many countries, for the early detection of these diseases, the analysis on TSH is recommended to do 1 time in 5 years even healthy people. But the ultrasound of the thyroid gland just do it meaningless. Ultrasound procedure absolutely does not reflect the function of the organ.

The main endocrine body, which participates in the regulation of pressure, is the adrenal glands. They produce three hormones, more precisely, three groups of hormones, each of which can increase pressure.

The first hormone is aldosterone, the second - cortisol, the third group is adrenaline and norepinephrine. From cells producing these hormones can develop benign tumorsAnd in this case, the production of hormones increases ten times.

If an excess of cortisol occurs, this is called Cushing syndrome (hypercorticism). In such patients, the mass of the body increases sharply, the belly bands appear on the skin - strry, sugar diabetes often develops. As a rule, this disease is recognized pretty quickly, since changes in appearance is one of the mandatory symptoms. For the diagnosis of this disease, the analysis of daily urine on cortisol is used.

The second disease associated with the excess work of the adrenal glands is hyperaldosteroneism (excess aldosterone). It can be caused by a tumor (aldoster) or hyperplasia (the growth of the tissue) of the adrenal gland. The disease is recognized very difficult, since in addition to increasing the pressure, it has practically no symptoms. In severe cases, especially against the background of treatment with diuretic drugs, muscle weakness can develop. Sometimes it is possible to suspect hyperaldosteroneism in the low level of potassium in biochemical analysis Blood, which is necessarily done hypertensive.

Finally, the peochromocytoma is the tumor of the brain layer of adrenal glands associated with the redundant release of adrenaline or norepinephrine. Most often this disease is manifested by heavy hypertensive crises with severe, heartbeat, sweating; The pressure at this moment sharply rises to 200-250 mm Hg. Art. Then the pressure drops sharply. Often, such an attack ends with abundant urination.

I must say that clinical picture Very similar to the attack of panic ( panic attack). That is why such patients sometimes have long and unsuccessfully treated with psychotherapists and even psychiatrists. The diagnosis of feochromocytomas is quite simple: you need to explore the level of metanephrines in the urine; normal result Allows almost 99% to exclude the diagnosis.

But the computed tomography of the adrenal glands only need to be done when an answer to the ability to excess one or another hormone came from the laboratory. It is not necessary to begin diagnostics with CT adrenal. Firstly, a number of hormone diseases have a nausea shape, we will simply see them on CT. On the other hand, about 5% of healthy people have small, hormonally inactive education in adrenal glands. They do not grow, are not the cause of hypertension and completely do not affect the life expectancy.

Patients with endocrine hypertension, as a rule, remain in memory of the doctor for a long time, since the disease occurs very fancy and, as a rule, does not fit into our classical ideas about hypertension. First of all, everyone is very surprised by excellent tolerance high pressure In these patients.

For example, my first patient, a 43-year-old man with aldosterone tumor of adrenal and pressure of 260/160 mm Hg. Art., I felt so good that I had signed a contract for the logger on Alaska. The second patient, a 30-year-old woman, walked with a pressure of 240/140 at least two years. Good well-being and almost complete lack of symptoms allowed her even "tool" from Philippine chiizers who convinced her that the tumor disappeared. Six months later, in our clinic she successfully conducted an operation and completely relief from hypertension.

Comment Article "Where hypertension is taken from? Checking the kidneys and treat snoring"

The article is extremely interesting, as doctors tend to prescribe hypotensive drugs after minimal analyzes.., The true cause of hypertension most often remains behind the scenes. In any case, so appointed a medicine for me in our district clinic. After reading this article, I already know about what analyzes I need to do. That's with this list and go to the clinic. Thank you!

11/28/2014 11:41:07, Valentina

The article is extremely useful

11/28/2014 11:32:09, Valentina

Total 2 posts .

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Hypertension causes heart, kidney disease, stroke, contributes to the development of diabetes. It is not a direct cause of a heart attack or stroke, but it contributes to a very large extent.

This is Edwa is not the most important, hypertension is "voltage disease." + Limitations of fat salty acute + lung sedative every day + ultrasound and kidney tests + osteopath rate (since. cervical osteochondrosis Also gives hypertension).

Thank you, I was waiting for the answer :) Tell me, pliz, where this time was observed about hypertension, if you are in Moscow. Yes, I almost forgot, before pregnancy, the kidneys examined and endocrine system (Shield. Iron and adrenal glands) to make sure that the hell with ...

Of course, if the causes of hypertension (kidney pathology, for example) persists, then hypertension will progress. Nevertheless, I know a bunch of people, "sitting" on the same dose of the same drug for 10-20 years.

hypertension. Has anyone come across a hypertension in a child? In the spring and now the cardiologist measures him pressure - 130/80. At home, too, sometimes 130, sometimes 120. The cardiologist says that it is not from I would also advise you to search for another nephrologist and kidney to finish completely.

Observe. It is necessary that primary: hypertension, vessels or kidneys. My mother turned out to be stenosis of the renal artery, after stenting the pressure was normalized (although it does not cancel, in its case of receiving certain drugs).

The main role in violation of purine exchange is played by kidneys and adrenal glands, well, in fact, the liver, that is, it is necessary to apply to the nephrologist and to the endocrinologist. Increased weight and hypertension can be straightforwardly associated with a violation of the kidneys.

In the diagnosis of hypertension there are two main points - find out whether hypertension with another disease (kidney, endocrinology, etc.) or this independent illness and determine how damaged by the target organs (heart, brain, kidney, vessels, eyes).

Complications: Hypertension, renal failure. I have a pyelonephritis of my left kidney ... some can have two at once. It is said that a third of pregnant women is sick with this disease (often it occurs during pregnancy).

Laboratory work number 2

Topic: "Measurement of blood pressure"

TARGET. Examine a biophysical mechanism for creating blood pressure, as well as the biophysical properties of blood vessels. Assimate theoretical foundations of the method of indirect measurement of blood pressure. Move the N.S. method Korotkov for measuring blood pressure.

Instruments and accessories. Sphygmomanometer,

phonendoscope.

Topics Study Plan

1. Pressure (definition, units of its measurement).

2. Bernoulli equation, its use in relation to blood movement.

3. The main biophysical properties of blood vessels.

4. Changing the size of blood pressure along the vascular bed.

5. Hydraulic resistance of vessels.

6. Methods for determining blood pressure according to the Korotkov method.

Brief theory

The pressure of P is called the value, numerically equal to the ratio of the power F, acting perpendicular to the surface, to the square s of this surface:

P s F.

The unit of measurement of pressure in SI - Pascal (PA), non-system units: millimeter of mercury pillar (1 mm Hg \u003d 133 Pa), centimeter of water column, atmosphere, bar, etc.

The effect of blood on the walls of the vessel (the ratio of the force acting perpendicular to the unit of the vessel area) is called arterial pressure. In the work of the heart, two main cycles are isolated: systoles (reduction of the heart muscle) and diastole (it is relaxing), therefore, the pressure systolic and diastolic is noted.

When reducing the cardiac muscle in the aorta, the blood filled with blood under the appropriate pressure is energized with a blood volume of 6570 ml, called the shock volume. Additional blood volume admitted in the aorta acts on the walls of the vessel, creating pressure systolic.

Wave increased pressure Transmitted to the remover of vascular walls of arteries and arteriols in the form of an elastic wave. This wave of pressure

called a pulse wave. The speed of its propagation depends on the elasticity of the vascular walls and is equal to 6-8 m / s.

The amount of blood flowing through the cross section of the site vascular system per unit of time, called the volumetric speed of blood flow (L / min).

This value depends on the pressure difference at the beginning and end of the section and its blood flow resistance.

Hydraulic resistance of vessels is determined by the formula

R 8, R 4

where - the viscosity of the fluid; - the length of the vessel;

r is a radius of the vessel.

If the area changes in the vessel, the total hydraulic resistance is located by analogy with a consistent compound of resistors:

R \u003d R1 + R2 + ... Rn,

where Rn is the hydraulic resistance of the range of the radius R radius and length.

If the vessel is branched onto the N vessels with hydraulic resistance RN, then the overall resistance is by analogy with parallel compound Resistors:

Resistance R system of branched vessels will be less than the minimum of vessel resistance.

In fig. 1 shows a graph of blood pressure changes in the main sections of the vascular system big Circle blood circulation.

Fig. 1. Where P0 is atmospheric pressure.

Pressure, excess on atmospheric, is considered positive. The pressure is less atmospheric - negative.

According to graphics. 1 It can be concluded that the maximum pressure drop is observed in the arteriols, and in Vienna - the pressure is negative.

The measurement of blood pressure is assigned an important role in the diagnosis of many diseases. Systolic and diastolic pressure in the artery can be measured directly using the needle connected with a pressure gauge (direct or blood method). However, the indirect (bloodless) method proposed by N.S. is widely used in medicine. Short. It consists next.

Around the hand between the shoulder and elbow impose a cuff capable of filling the air. First, the excess over atmospheric air pressure in the cuff is equal to 0, the cuff does not compress soft tissues and artery. As air supplied to the cuff, the latter squeezes the shoulder artery and stops blood flow.

The air pressure inside the cuff consisting of elastic walls is approximately equal to pressure in soft tissues and arteries. This is the main physical idea of \u200b\u200bthe bloodless pressure measurement method. Release air, reduce pressure in cuff and soft tissues.

When the pressure becomes equal to systolic, blood will be able to break through at high speed through a very small cross section of the artery - while the flow will be turbulent.

Characteristic tones and noises accompanying this process listens to the doctor. At the time of listening to the first tones, pressure (systolic) is recorded. Continuing to reduce the pressure in the cuff, the laminar flow of blood can be restored. The noise stops, at the time of their termination they register diastolic pressure. To measure blood pressure, the device is used - a sphygmomanometer consisting of pear, cuffs, a pressure gauge and the phononendoscope.

Questions for self-control

1. What is called pressure?

2. What units is the pressure measured?

3. What kind of pressure is considered positive, what a negative?

4. Formulate Bernoulli rule.

5. Under what conditions is the laminar nature of the fluid flow?

6. What is the difference between the turbulent flow of flow from laminar? Under what conditions is the turbulent fluid flow observed?

7. Record the formula of the hydraulic resistance of the vessels.

9. What is systolic arterial pressure? What is it equal to healthy man at rest?

10. What is called diastolic arterial pressure? What is it equal in vessels?

11. What is a pulse wave?

12. In which cardiovascular system is the greatest drop in pressure? What is it due to?

13. What is the pressure in venous vessels, large veins?

14. With which device, blood pressure is measured?

15. What components contains this device?

16. What is due to the appearance of sounds when determining blood pressure?

17. At what point is the point of the instrument, the systolic pressure of the blood corresponds to systolic pressure? At what point the diastolic pressure of the blood?

Work plan

Sequence			Method of assignment.
action
1. Check			Created pressure should not change within 3
tightness.
	Determine		1. Spend 3 times measurements, the readings will enlist
systolic			table (see below).
diastolic	pressure		2. impose a cuff on the naked shoulder, find
right and left hands			on the elbow bending pulsating artery and
method N.S. Short			set over it (not pressed strongly)
			phonendoscope. Create pressure in the cuff and then
			slightly opening the screw valve, produce air that
			leads to a gradual decrease in pressure in the cuff.
			At a certain pressure, the first weaknesses are distributed
			short-term tones. At that moment fixed
			systolic blood pressure. With further
			reducing pressure in the cuff tones are louder,
			finally, they dramatically drunk or disappear. Pressure
			air in the cuff at that moment is accepted for
			diastolic.
			3. Time during which measurement is performed
			pressure on N.S. Short, should not last more than 1
	Definition		1. Make 10 squats.

systolic							2. Implement pressure on the left hand.
diastolic			pressure				3. Remove the testimony to the table.
blood according to the Korobov method
after exercise.
			Definition				Repeat measurements after 1, 2 and 3 minutes. after
systolic						exercise.
diastolic			pressure				1. Implement pressure on the left hand.
blood at rest.							2. Discovery to put in the table.
	Norm (mm Hg)							After load		After rest
	Singer. Pressure.				Diast. Pressure.
			Registration				1. Compare the results obtained with normal
laboratory work.						blood pressure.
							2. Take a conclusion about the state of cardiovascular

negative pressure - Gas pressure less environmental pressure. [GOST R 52423 2005] Themes of inhale. Anesthesia, arts. fan. Easy EN Negative Pressure de Negative Druck FR PRESSION NEGATIVEPRESSION SUBATMOSPHÉRIQUE ...

negative pressure

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Pressure negative - - pressure below atmospheric, celebrate in veins, pleural cavity … Dictionary of terms in physiology of farm animals

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BLOOD PRESSURE - blood pressure, pressure that blood produces on the walls of blood vessels (t. N. Lateral blood pressure) and on that pole of blood, to the pimy fills the vessel (so on. End pressure of blood). Depending on the vessel, it is measured by K. d. ... ...

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One of the main parameters of the ventilation system is pressure. The fan, the suction air from the atmosphere and inserting it into the volume, creates a certain pressure difference between the ambient and this volume. In this publication, we are simply "pressure", if it is correlated with standard pressure. Since the difference can be positive or negative, Will vary positive and negative pressure. Both are measured relative to the standard air pressure.

In ventilation systems can also be used positive, I. negative pressure. It depends on whether air is removed from the volume or is injected into the volume.

The fan, taking the outside of fresh air, will first create some negative pressure in the air duct between the air intake and the fan. This negative pressure causes the stream of air from the street (where the pressure is higher) into the air intake. Depending on the resistance of the air intake and the power of the fan, this pressure can achieve values \u200b\u200bdangerous for our products. Next, explains what happens if a negative pressure occurs in the air duct, and which protective measures should be taken to prevent damage to the air duct.

2. The difference between positive and negative pressure

It is very important to keep in mind that the positive and negative pressure is on ducts different influence. Positive pressure in volume creates forces directed outward. These forces arise from the blows of the molecules about the wall wall.

3. Negative pressure in flexible air ducts

When air is pumped into the balloon, its volume increases. Due to the increase in voltages in the walls, the inverse force arises, equilibrium is achieved and the stretching stops. Negative pressure inside the volume leads actually to the same result. Efforts arise, but now aimed into the volume. The behavior of the volume depends on its size and structure of the walls. It is known that large volumes are more sensitive to pressure than small. This is explained by the fact that the pressure is equal to the strength applied to a certain area. The pressure of 1000 Pa creates force corresponding to the action of a mass of 100 kg. On the area of \u200b\u200b1 m 2. An increase in volume (increasing diameter) leads to an increase in the total force acting on the wall surface.

It is not necessary to explain that a flexible air duct with a large diameter will be less resistant to negative pressures. There are two types of deformation of flexible air ducts negative pressure. The air duct can either be confused, or subjected to the so-called "Domino effect".

Below will be explained both of these types of air ducts.

4. Domino effect

Depending on the design of the flexible air duct, several effects may be observed. On several subsequent drawings, the effect will be shown, most significant for flexible air ducts.

Drawing 1.

Such is normal the position of the wire spiral in the wall of the flexible duct, if it is listed on the side.

Two adjacent wire turns are connected by a duct layered material. Depending on the nature of this material, the distance between the wires of the wire may be different. The wire prevents formation on the air duct dentin, etc. However, the layered material also gives the air duct rigidity or softness.

It has already been said that the forces created by negative pressure in the air duct are directed inside the duct. Usually their direction is perpendicular to the wall of the air duct. In this case, the wire, as well as the layered material, must withstand these efforts.

The drawing of 2 effort is shown by arrows. In this case, the maximum allowable force is determined by the resistance to the rupture of the wall material.

Drawing 2.

It will be about the same as the maximum positive pressure, which is shown by arrows directed in the opposite direction (drawing 3).

Drawing 3.

Unfortunately, the situation is not quite true. In fact, the turns will be folded as a row of domino bones (see drawing 4).

With this movement, the volume inside the air duct decreases under the action of the force of the outdoor pressure.

Drawing 4.

For the manifestation of this effect, a much smaller force is required. It is useful to know which important parts of the duct determine the resistance to the domino effect.

Depending on the nature of the materials, the movement of the air duct will counteract a large or smaller force. However, this force is much smaller than the force required for the rupture of the material. The gap can occur when annexed too much positive pressure. Therefore, the maximum negative pressure that can withstand a flexible duct, much less than the maximum positive pressure.

Based on this output, we come to one of the most important factors that determine the behavior of the flexible air duct under negative pressure. How can you achieve optimal resistance to negative pressure?

To achieve this, it is necessary to minimize the probability of the Domino effect. For this there are several possibilities:

1. For the air duct walls, you can use more hard material. A tighter material will not be easily frozen, and therefore deform the rectangle will be harder. However, the product will be less flexible accordingly.
2. You can use thicker wire. Wire rigidity determines the resistance to deformation in accordance with "action 1".
3. Deformation of the rectangle is hampered with a decrease in the steps of the wire spiral. "A" and "D" become shorter, as a result of which "C" and "B" are closer to each other. Shift "C" relative to "B" becomes harder. Reducing the steps of the turns of the wire is very good way Increase the resistance to negative pressure, however, the price of the air duct increases accordingly.
4. The last opportunity is one of the most important! The first three ways should be implemented by the manufacturer, since the structure of the air duct wall changes. The last method can be implemented by the user of the air duct without any changes in the design of the real duct. Since this last method has a great influence on the ability of the air duct to resist negative pressure, it will be paid slightly more attention to its explanation. The drawing 5 shows the air duct, experiencing the domino effect.

Drawing 5.

As a rule, points P., Q., R. and S. attach to any ??&&??&& which is attached to the main ventilation system. therefore P.will be straight over Q., but R. over S.. In fact, the air duct shown in the drawing 6 must be mounted as shown in the drawing 6.

Drawing 6.

P. Located right above Q., but R. over S.. The first and last turns of the wire must be located vertically. The coys are deformed in the midst of negative pressure. However, these medium turns may be subject to the domino effect only if at points P. and S. There is a sufficient stock of the material. Material at point Q. shrink, and at the point P. It is stretched so that the wire gets the possibility of offset according to the domino effect.

If there is no reserve, the laminate will hold the wire in the position shown in the drawing 7. This will be observed if the flexible air duct was completely stretched and connected to the accessories with some tension. It can be said that at the same time each turn is stretched on both sides and therefore is unable to shift.

Due to this, the effect of domino is prevented! Mounting this method is difficult if the form of the duct should be curved. Despite this, it is important to mount the air duct in an optimal position and properly stretch and connect it.

We considered the first of two types of damage to flexible air ducts by negative pressure. The second type is crumpled.

Drawing 7.

5. Smiling

This effect is observed if the air duct's wire helix is \u200b\u200bless durable than the wall design. This means that the design of the walls is better resisting the domino effect than the wire spiral of the crum. The deformations arising from the duct crumplement are the same as if we put a heavy item on the air duct. The air duct is simply flattened. For this, all coils of the spiral must be turned into an oval or even in the plane.

• Wire bends in two places of each turn. It is not difficult to understand that the resistance of such a mortification increases if the wire thickness increases or the distance between the wires of the wire is reduced. This explains why the duct of the vacuum cleaner has a thick wire and very small steppes.
• It is very important to keep in mind that the stability of the flexible duct falls very much with increasing diameter. The forces acting on the surface of the duct of larger diameter create large stresses in the wire spiral, and therefore the air duct is easier to crush. If with a very large diameter, for example 710 mm., Use too thin wire, the air duct will be frozen almost under the action of its own weight. Very small pressure can cause complete flattening.
• The user can almost do anything to increase resistance to crumbles. When the air duct reaches the limit of its capabilities, it begins to deform and turns into an oval, the user is not able to take anything other than reducing the negative pressure or the use of the best air duct.

6. Conclusion

We saw that the negative pressure is more dangerous for the air duct than positive. Depending on the diameter and the design of the air duct walls, a crumpled or the domino effect will be observed. If the first domino effect occurs, the user can take some measures to significantly improve the behavior of the air duct due to proper installation. But as soon as the mixture effect occurs, you can be sure that the limit of the capabilities of this duct has been achieved.

It is possible to estimate the behavior of the flexible duct with negative pressures using laboratory tests, but the results will always relate only to the test situation to the duct form used in these specific tests. The deformation of the air duct during installation due to negligent circulation, as well as the installation method can have so much influence that the data obtained will not be correct.

Positive pressure at the end of the exhalation (PDKV, PEEP) and constantly positive pressure in the respiratory tract (PDDP, Cryt).
PDKV (PEEP) methods and PDDP (CPAR) have long and firmly entered the practice of IVL. Without them, it is impossible to imagine effective respiratory support in heavy patients (13, 15, 54, 109, 151).

Most doctors, without even thinking, automatically include the PDKV regulator on the breathing apparatus from the very beginning of the IVL. However, it is necessary to remember that PDKV is not only a powerful weapon of a doctor in the fight against severe pulmonary pathology. Thoughtless, chaotic, on "Eye" Application (or sharp cancellation) PDKV can lead to serious complications and deterioration of the patient's condition. A specialist conducted by IVL is simply obliged to know the essence of PDKV, its positive and negative effects, indications and contraindications to its use. According to modern international terminology, generally accepted English-speaking abbreviations: for PDKV - Peep (PDDDP PRESSURE (Continuous Positive Airway Pressure). The essence of PEEP is that at the end of the exhalation (after a forced or auxiliary breath), the pressure in the respiratory tract is not reduced to the zero level, and
It remains above atmospheric for a certain amount established by the doctor.
PEEP is achieved by electronic control of the expiratory valve mechanisms. Without preventing the start of the exhalation, subsequently at a certain stage of the exhalation, these mechanisms overlap the valve to a certain extent and thereby create additional pressure at the end of the exhalation. It is important that the PEEP valve mechanism does not create.1. Additional expiratory resistance to the main phase of exhalation, otherwise PMEAN increases with the corresponding undesirable effects.
The function of the CPAR is designed primarily to maintain constant positive pressure in the respiratory tract during the spontaneous breath of the patient from the contour. The shit mechanism is more complicated and is provided not only by overlapping the expiratory valve, but also automatic adjustment of the level of constant flow of the respiratory mixture in the respiratory circuit. During the exhalation, the flow of this is very small (equal to the base expiratory flow), the value of the Cryp is equal to the PEEP and is maintained, mainly due to the expiratory valve. On the other hand, to retain a given level of a certain positive pressure and during a spontaneous breath (especially at the beginning). The device submits to the contour a fairly powerful inspiratory flow corresponding to the inspiratory needs of the patient. Modern fans automatically adjust the flow level by supporting the specified crash - the "flow flow" principle ("Demand Flow"). With spontaneous attempts to the inhalation of the patient, the pressure in the circuit moderately decreases, but remains positive due to the supply of the inspiratory flow from the apparatus. During the exhalation, the pressure in the respiratory tract at first moderately increases (because it is necessary to overcome the resistance of the respiratory contour and expiratory valve), then becomes equal to PEEP. Therefore, the pressure curve when Crypt is sinocoued. A significant increase in the pressure in the respiratory tract does not occur in any phase of the respiratory cycle, since the expiratory valve remains at least during the inhalation and exhalation, the expiratory valve remains partially open.