Pathological Mechanism of Wei-Qi-Ying-Xue
1. Pathological Mechanism of Wei-Stage
The patho-mechanism of wei-stage refers to the pathologic changes which include the functional disorder of defensive qi caused by the invasion of the warm-evil. The weistage is a stage in which the warm or heat-evils stay in the exterior. The warm and heatevils attack the body by way of the mouth and nose. They invade the skin and muscles at first, then the lung. The location of this disease, therefore, is the skin and lung enter
The state of the disease is relatively mild and shallow.
The physiological function of defensive qi is to guard against the exogenous evils from invasion, to warm the skin and muscles, to control the opening and closing of sweat Pores, and to regulate the body temperature. The lung correlates with the skin and hair.lithe defensive-qi and lung-qi are closely related. When warm or heat-evil invades the skin or mouth and nose, it will lead to a disorder between the lung and the defensive qi. So the main patho-mechanism of wei-stage is characterized by the invasion of exogenous warm or heat-evil, the stagnated defensive-qi and yang, skin and muscle malnutrition, and the dysfunction of lung in its dispersing and depurative descending functions. Fever, slight aversion to cold, lack or insufficiency of perspiration, slight thirst, red tip and margin of tongue, and a floating rapid pulse are the clinical manifestations. Among these, simultaneous serious fever and slight aversion to cold, are the most common characteristics of wei-stage syndrome.
2. Pathological Mechanism of Qi-Stage
Qi-stage is a stage in which the-warm or heat evil is in the interior of the body. The patho-mechanlsm of qi-stage is manifested in the disorder between the circulation, dispatching, ascending and descending, and exiting and entering of qi, and even some functions of viscera. This is caused by the entrance into the interior of the stagnated evils in the incurred wei-stage disease, and the disease's transmission into qi-stage. It also could be caused by a direct attack by the evils upon the qi-stage.
Besides the invasion on wei-stage and direct attack on the qi-stage, it also is possible that the latent evils may attack at the inner part of the body. The so-called latent evils are a comparative term in relation to the new affected evils. A disease caused by latent evils is a kind of warm disease in which the external evils invaded the body and did not cause onset of disease at that time, but instead became latent evils. Then, at an opportune moment, they cause the onset of disease. Or interior heat exists in the human body,they can be activated by the new affection of external evils. Because the disease begins with the interior syndrome, and has symptoms of heat stagnated in the interior as its main reactions, it is different with the warm disease caused by new affection, which begins with a exterior syndrome. The transmitting tendency of this kind of disease can be either to the exterior, or to sink further inside.
The pathological change of qi-stage syndrome ranges far and wide. As regards the location of the disease, it involves many viscera and body parts, including the lung,and diaphragm, stomach, intestines, gall bladder, spleen, etc. It reflects the pathological changes of a extreme stage in many EFDs. So all pathological changes in which warm or heat evils enter the interior, but have not entered the ying and xue-stage, can be classified into qi-stage syndrome.
Because the warm or heat evils invade internal viscera and meridians, the genuine-qi struggles against the evil-qi in the inner part. The evil-qi is exorbitant and genuine-qi is strong, thus, the struggle between the evil-qi and genuine-qi is fierce. That leads to a hyperactivity of the viscera. The pathomechanism is characterized by the excessive interior heat. The main clinical manifestations are high fever or tidal fever, or some other obscure fever, aversion to heat but not cold, red tongue with yellow coating, and a rapid powerful pulse. They are often accompanied by vexation, thirst, flushed face, asthma or cough, stuffiness or choking sensation in the epigastrium, vomiting, nausea, or constipation. Among these, fever with an aversion to heat but not cold, thirst, and yellow coating on the tongue are the most common features.
The pathologic reactions differ depending upon the viscera that is affected. For example, in the condition of excess heat in the lung, the lung can not function well, leading to fever, cough, and asthma. If heat disturbs the chest and diaphragm, the qi can no flow freely, and there will be vexation and fever. If excess heat burns the stomach and impairs the body fluid, there will be sthenic fever, thirst, yellow tongue coating,and surging pulse. When heat accumulates in the intestines, fu-viscera-qi is blocked, and there will be tidal fever, constipation, and a dry-yellow tongue coating. When heat stag.nates in Shaoyang, and gallbladder-fire flames, then there will be more fever feeling than aversion to cold in the alternating fever and chills, a bitter taste in the mouth, and a yellow tongue coating. When damp-heat accumulates in spleen, there will be obscure fever,stuffiness of the epigastrium, vomiting, or nausea. If body fluid was consumed by the heat evil, there will be thirst and, and a red tongue with yellow coating or dry-white coating. If extreme heat impairs body fluid and leads to a inner liver-wind, there will be
spasm in the limbs, neck stiffness, and opisthotonos. In summary, no matter how com-
plex the clinical manifestations of qi-stage are, they have a common characteristic of excessive heat. All the symptoms reflect the strong body resistance and abundant heat evils.
3. Pathological Mechanism of Ying-Stage
The pathomechanism of ying-stage refers to the pathologic changes caused by warm
or heat-evils which intrude into the deep ying-stage and injure the nourishing material.The heart dominates blood and pertains to ying. So the disease of ying-stage is located in the heart and pericardium.
The ying-stage disease occurs when the qi-stage disease is not cured, when genuine-qi becomes weak and body fluid is insufficient. Taking advantage of genuine-qi deficiency, the heat-evil enters the further interior part, and reaches the heart and ying. The ring-stage disease can also be caused by a direct attack on ying-stage from wei-stage disease. In this stage, the body is in a state in which nutrient-yin (body fluid in the blood) is injured. Heat-evil then sinks into the pericardium, and mind in heart is disturbed. The main clinical manifestations are crimson tongue, vexation, insomnia, tidal fever aggravated at night, paroxysmal delirium, obscure macule and papule, and a rapid thready pulse.Among these, crimson tongue is the main characteristic of the syndrome of heat-evil in the nutrient-yin. If heat in ying-stage stirs the liver-wind, there will also be symptoms of spasm, neck stiffness, opisthotonos, etc.
4. Pathological Mechanism of Xue-Stage
The pathomechanism of xue-stage is a pathologic change of the last stage in the wei-qi-ying-xue transmission. It is also the deepest and most severe stage of the whole process of warm disease. When evils enter :rue, they will consume and stir the blood. The heatevil in this case is more excessive than that of ying-stage. Thus the blood is compelled to flow extraordinarily, and mind in heart is disturbed. Because the heat-evil is in a deeper yin-stage, the damage of the body nourishing material is more severe.
The heart dominates blood, liver stores blood, kidney stores essence, and essence and blood can transform into each other. So the location of xue-stage disease is mainly in the heart, liver, and kidney. The pathomechanism characteristics are that heat compels blood to flow extraordinarily, blood flows out of the vessel, and heat in blood injures the tendons and leads to endogenous wind stirring of liver. Blood and body fluid are damaged heavily. Besides these symptoms of ying-stage, other characteristics include blood consumption, blood stirring (bleeding), yin consumption, endogenous wind, and the disturbed heart mind. If heat stirs the blood, there will be bleeding disorders such as heamatemesis, epistaxis, hematochezia, hematuria, colporrhagia, metrorrhagia, macule and papule, and so on. If heat in blood stirs the liver-wind, there will be spasm and convulsion. If heat in blood interferes in the mental activity of heart, and the mind is in disorder, there will be coma, delirium, madness, stupor, and restlessness, etc.
In addition, if the disease is not cured in xue-stage, the excessive heat evil consumes body fluid and yin, and results in a syndrome as described by Wu Jutong as- "Warm disease in its Shaoyin with a nearly exhausted genuine-yin-a sthenic fire. " The prolonged staying of heat-evil consumes the liver-blood and kidney-essence. In this stage, yang depletion or yin depletion also may occur. They result from the depletion of body-fluid which is caused by the abuse of diaphoresis, sudden blood loss, over vomiting or heavy diarrhea. The pathological reaction of yin-essence deficiency and internal deficient heat can often be seen in clinical practice. Pathological reactions such as collapse can also be seen, which are due to the inability of yin-essence, blood and body fluid to nourish important viscera. When this occurs, if emergency treatment can not be applied in time, the patient will be in danger.
