In the human body, some organsare represented by pairs: lungs, kidneys, limbs. Others - this is mainly the organs of the abdominal cavity - are unpaired: spleen, intestine, stomach. This explains the peculiarities of the blood supply to the abdominal cavity, especially the formation of the venous system. The portal vein is a vessel through which blood flows from the internal organs to the liver.
Why a man needs a portal vein
It should be noted that this blood vessel is a unique anatomical formation of the human body.
First, the portal vein is the shortesta blood vessel of this caliber. Its length is only 5-7 cm (from the moment of fusion of the mesenteric veins and the venous spleen and to the place the entry of this blood vessel into the liver), whereas the diameter of this vein can even up to 1.5-2 centimeters in the absence of pathology.
Secondly, along this venous trunk, all blood coming from the digestive tract is collected and delivered to the liver cells, where its disinfection takes place.
However, the portal vein system does notis limited only by this vessel. It also includes the veins that are connected in it, and those hepatic veins, to which this trunk disintegrates after it enters the liver. Directly in the portal of the liver, the vein is divided into the right and left branches, which in turn branch out farther and farther until they reach the hepatic lobules.
Accordingly, through this blood vesselpasses all the blood that is collected from the organs of the abdominal cavity (primarily from the digestive tract). In the liver cells, metabolic processes occur in the decomposition and transformation of most harmful substances into useful or indifferent to the body.
The portal vein has collateral (bypass)connection with the veins of the stomach. Therefore, if there is an obstacle in it, untreated blood gets to the rest of the organs of the human body, very quickly causing the characteristic symptoms of intoxication, whereas in the venous system of the stomach, changes begin that resemble those that occur during the development of hemorrhoids in the veins of the rectum plexus.
Diseases of the portal vein - how they manifest themselves
В настоящее время тромбоз воротной вены является the most frequent disease of this blood vessel. The emergence of it in the vast majority of cases signals the presence in the human body of problems requiring immediate and effective treatment. Most often this disease develops in patients that suffer from malignant neoplasms of the liver, cirrhosis, severe bleeding disorders, sepsis.
В этом случае квалифицированная медицинская Assistance should be provided in the fullest possible extent. In the absence of treatment, this condition leads to a rapid development of liver abscesses, acute liver failure and death of the patient. Simultaneously, a survey should be conducted, the purpose of which should be to identify the cause that caused a violation of blood flow in the portal vein system.
Why not all medicines can be taken orally
It should be noted that most of the drugs prescribed to a person are absorbed in the intestines and necessarily enter the portal vein.
In some cases, the ingress of the drug into the liver is necessary. There it turns from an inactive form into an active one and begins its therapeutic action.
В других случаях попадание лекарства в печень undesirable. The only way to prevent this is the resorption of the drug in the oral cavity (some heart drugs - nitroglycerin and its derivatives, cardiac glycosides), rectal or injection injection. In this case, the portal vein will not participate in the transportation of the drug.