What is the mechanism of the formation of the strange pulse? What is Strange Pulse?

Prerequisites for the occurrence of paradoxus (non-pathological): during inspiration, the negative pressure of the pleural cavity is more negative, the large proximal vein is dilated, the pressure difference between the systemic veins increases, and the blood volume of the right heart return increases; The pulmonary circulation blood vessels are also dilated, so the storage volume increases, and the amount of blood in the left ventricular return decreases.

Based on this premise, in some pathological cases, the left ventricular gyrus blood volume is further reduced, leading to the production of pulsus paradoxus:

1. Decreased right ventricular ejection, which is seen in right heart failure and emphysema.

COPD (pulmonary hypertension).

2. The limited volume of ventricular expandability leads to a left shift of the ventricular septum, which is seen in cardiac tamponade and constrictive pericarditis.

3. The negative pressure of the pleural cavity is further increased, resulting in a further increase in the storage volume of the pulmonary circulation, which is seen in severe asthma.

When respiratory muscle paralysis fails to compensate for a decrease in intrathoracic pressure, pulsus paradoxus disappears).

Paradoxus check-up items.

1. Blood test.

Pericardial effusion. Constrictive pericarditis and pleural effusions are often associated with elevated white blood cell counts and erythrocyte sedimentation rate.

Rapid and restrictive cardiomyopathy is more pronounced with eosinophilia. Blood gas analysis.

In chronic obstructive pulmonary emphysema, if there is significant hypoxia and carbon dioxide retention, the arterial partial pressure of oxygen decreases and the partial pressure of carbon dioxide increases.

2. Other auxiliary examinations.

1) X-rays. Chest x-ray or cardiac shadow on radiograph is enlarged to the sides and appears flask-shaped, and decreased or absent cardiac beats suggest pericardial effusion; The heart shadow is triangular in shape.

calcification of the pericardium, suggesting constrictive pericarditis; Sheet-dense, homogeneous opacities in the lungs suggest pleural effusion; Increased luminosity in the lung field suggests emphysema.

2) Electrocardiogram.

Low voltage, electrical alternation, and elevation of the apical segment under the arch dorsal segment are more suggestive of pericardial effusion.

3) Echocardio** can find specific changes in constrictive pericarditis, pericardial effusion, cardiomyopathy, etc. Ultrasonography is also specific for the diagnosis of pleural effusion.

4) Left ventricular restrictive cardiomyopathy shows endocardial hypertrophy and cardiac chamber shrinkage. Cardiac radionuclide examination has auxiliary diagnostic value for pericardial effusion and cardiomyopathy.

5) Pulmonary function tests: Obstructive emphysema is characterized by diffusion disorder, decreased maximum ventilation, and increased residual volume.

The production of pulsus paradoxus is mainly related to the left heart stroke volume, and the blood volume of normal people returning from the pulmonary veins to the left ventricle decreases due to the expansion of the lungs during inspiration, and the left ventricular stroke volume decreases by about 7% on average, and the arterial systolic blood pressure decreases by an average of 3%, and the pulse of the radial artery is weakened at this moment. When the lungs return to their original state during exhalation, the volume of blood from the pulmonary veins to the left ventricle increases, and so on periodically changes with breathing. However, it is usually not felt, so there is no significant change in the pulse.

According to the clinical hemodynamic echocardiographic observations and animal experiments in recent years, it is believed that inspiration during cardiac tamponade increases right ventricular reflux, decreases left ventricular filling and produces paradoxus.

1. In pericardial effusion and constrictive pericarditis, diastolic ventricular filling is limited, the blood volume of the pulmonary circulation increases during inspiration, and the blood is trapped in the blood vessels, resulting in the blood flow of the upper and lower vena cava to the right heart can not be increased correspondingly, so that the amount of pulmonary venous blood flow to the left ventricle is reduced compared with normal.

2. During inspiration, the septal muscle descends, which pulls the tense pericardium, further increases the pressure in the pericardial cavity, restricts the ventricular filling and further reduces the left ventricular filling.

3. The increase of right ventricular filling displaces the ventricular septum to the left ventricular cavity, thus limiting the left ventricular filling, resulting in decreased aortic blood flow and low pressure and the appearance of paradoxus.

4. Emphysema, asthma, pleural effusion, etc., which affect the right ventricle's blood discharge to the lungs, can also occur when paradoxus can occur.

Paradoxuspulsus, in which the pulse is markedly diminished or absent during inspiration, is due to decreased left ventricular stroke volume.

The strength of a normal person's pulse is not affected by the respiratory cycle.

When there is cardiac tamponade or pericardial coarctation, on the one hand, due to the restriction of right ventricular diastolic, the blood volume of the right heart is reduced, and the blood volume discharged into the pulmonary circulation of the right ventricle is correspondingly reduced. On the other hand, the pulmonary circulation is affected by the negative pressure of the chest during inspiration, and the pulmonary blood vessels dilate, resulting in a decrease in the amount of pulmonary venous return to the left atrium, and thus a decrease in left ventricular output.

These factors cause the pulse to weaken or even be palpable during inhalation, so it is also called "aspiration and arrest pulse".

When a normal person breathes calmly, the strength of the pulse usually does not change, or only changes slightly. When you breathe calmly, the pulse is significantly weakened or even disappears, which is called a paradoxus. Common in pericardial effusion and constrictive pericarditis, it is one of the important signs of cardiac tamponade.

The mechanism of paradoxus is due to a decrease in left ventricular output.

Pulsus

paradoxus）

Western medicine: refers to the significant weakening or disappearance of the pulse during inhalation, also known as aspiration and arrest of the pulse. It is due to increased pressure in the pericardial space, which limits diastolic filling of the heart. It is common in pericardial effusion and constrictive pericarditis, as well as severe asthma.

Traditional Chinese Medicine: Refers to the eight veins of the Qi Jing. See this article for details.

Pulse noun. Pulses that do not match the color. "Su Wen: The Generation of the Five Organs": "The strange veins of the five colors of all phases ......."Wang Bing's note: "The strange veins are said to be incompatible with the color." ”

What are the criteria for diagnosing pulsus paradoxus Detectable when a clear palpation pulse is evident; A blood pressure monitor may be used to reduce arterial systolic blood pressure by 10 mmHg or more during inspiration compared with pre-inspiration.

Western medicine: refers to the significant weakening or disappearance of the pulse during inhalation, also known as aspiration and arrest of the pulse. Due to the increase of pressure in the pericardial cavity, the ventricular diastolic filling is limited, the systemic venous return is limited during inspiration, and the blood volume of the right ventricular drainage is reduced into the pulmonary circulation, and the pulmonary circulation is affected by the negative pressure of breathing, and the pulmonary blood vessels are dilated, resulting in a decrease in the amount of blood flowing back into the left heart of the pulmonary vein, and a decrease in the left cardiac output, resulting in a weakened or even disappeared pulse.

It is common in right-sided heart failure, pericardial effusion, constrictive pericarditis, and severe asthma.

Traditional Chinese Medicine: 1. Refers to the eight meridians of the strange meridians, that is, a category of the meridians of the human body;

2. Pulse noun refers to the pulse that does not match the color matching filial piety.

Pulses are when we breathe, and when we inhale, the pulse suddenly weakens or disappears.

The pulse of a normal person is not affected by breathing, but if we have a certain disease, our breathing will sometimes affect our pulse, and some more dangerous symptoms will appear at this time, so this is called the strange pulse in Chinese medicine.

When we have some diseases in the heart, such as constriction of the pericardium, or the symptoms of heart crushing, then at this time, our heart injury will be limited, and the amount of blood we flow back to the heart will also be reduced, which will affect the pumping function of our heart, thereby affecting a series of new functions and reducing cardiac output.

At the same time, the oxygen consumption of the heart will also be reduced, which will reduce the amount of blood in the pulmonary circulation in our whole body, on the other hand, the systemic circulation will also affect the function of the whole heart, so it will make the pulmonary blood vessels dilate, and the cardiac output will decrease, which will cause us to weaken the pulse when we inhale, and even sometimes we can't feel the pulse.

The main cause of Pulsus is heart problems, so it is very common to have constrictive pericarditis due to pericardial effusion, or because of some inflammation of the pericardium.

Pulse: refers to the significant weakening or disappearance of the pulse during inhalation, also known as the inhalation and stopping pulse. Restriction of ventricular diastolic filling due to increased pressure in the pericardial cavity <>

The strange reading ji in the medicine Richie pulse is still qi

Pulse paradoxus: refers to the significant weakening or disappearance of the pulse during inhalation, also known as aspiration and abortion. Due to the increase in pressure in the pericardial cavity, the ventricular diastolic filling is limited, the venous return of the body silver is limited during inspiration, the blood volume of the right ventricle into the pulmonary circulation is reduced, and the pulmonary circulation is affected by the negative pressure of breathing, and the pulmonary blood vessels are dilated, resulting in a decrease in the amount of blood flowing back into the left heart of the pulmonary vein, a decrease in the output of the left heart, and a decrease in the pulse pulse.

Symptomatic reflex is seen in pericardial effusion and constrictive pericarditis, as well as severe asthma.