Enterosorption

Enterosorption refers to the so-called non-invasive sorption methods, since it does not involve direct contact of the sorbent with blood. In this case, the binding of exogenous and endogenous toxicants in the gastrointestinal tract with enterosorbents - therapeutic preparations of various structures - occurs by adsorption, absorption, ion exchange and complexation, and the physicochemical properties of sorbents and the mechanisms of their interaction with substances determine their structure and surface quality.

Absorption is the process of absorbing sorbate with the entire volume of the sorbent, which is the case when the liquid acts as sorbent, but the process of interaction with the sorbate, in fact, the dissolution of the substance. The absorption process takes place during gastric or intestinal lavage, as well as when enterosorbents enter the liquid phase, where absorption occurs. The clinical effect is achieved if the solvent is not absorbed or after the introduction of the liquid is soon removed from the gastrointestinal tract.

Ion exchange is the replacement process of ions on the sorbent surface by sorbate ions. Anion exchangers, cation exchangers and polyampholytes are distinguished by ion exchange. Replacement of ions to some extent is possible in all enterosorbents, but ion exchange materials are only those where this type of chemical interaction is the main (ion exchange resins). In some cases, it is necessary to prevent excessive release into the chyme and absorption of electrolytes, which occurs during ion exchange in the enteric environment.

Complexation takes place during neutralization, transport and excretion of target metabolites from the body due to the formation of a stable bond with the ligand of the molecule or ion, the resulting complex can be either soluble or insoluble in the liquid. From the number of enterosorbents to complex formers are the derivatives of polyvinylpyrrolidone.

[1], [2], [3], [4], [5], [6],

Basic medical requirements for enterosorbents

• nontoxicity Preparations in the course of passage through the digestive tract should not degrade to components that, when absorbed, may have a direct or indirect effect on organs and systems,
• non-traumatism for the mucous membranes. Mechanical, chemical and other types of adverse interactions with the mucous membrane of the oral cavity, esophagus, stomach and intestines, leading to damage to organs,
• good evacuation from the intestine and the absence of reverse effects - strengthening processes that cause dyspeptic disorders,
• high sorption capacity in relation to the removed components of chyme, for non-selective sorbents, the possibility of loss of useful components should be minimized,
• The absence of desorption of substances in the process of evacuation and changes in the pH of the environment, which can lead to adverse manifestations,
• convenient pharmaceutical form of the drug, allowing its use for a long time, the absence of negative organoleptic properties of the sorbent,
• favorable influence or absence of influence on the processes of secretion and biocenosis of gastrointestinal microflora,
• Being in the intestinal cavity, the sorbent should behave as a relatively inert material, without causing any reactive changes in the intestinal tissue, or these changes should be minimal and comparable to those that are traced when changing the diet.

To carry out enterosorption, oral administration of enterosorbents is most often used, but if necessary, they can be injected through the probe, and in the case of probe insertion, preparations in the form of a suspension or a colloid are more suitable, since granular sorbents can enclose the probe lumen. Both of the foregoing administration methods for enterosorbent are necessary for performing so-called gastrointestinal sorption. Enterosorbents can be injected into the rectum (colosorption) with the help of enemas, however, sorption efficiency in such a way of sorbent administration is usually inferior to oral.

Nonspecific sorbents in each department of the gastrointestinal tract carry out the sorption of these or other components depending on the composition of the enteric environment. Removal of xenobiotics, ingested orally, occurs in the stomach or in the primary parts of the intestine, where their highest concentration remains. In the duodenum begins the sorption of gallstones, cholesterol, enzymes, in lean - products of hydrolysis, food allergens, in thick - microbial cells and other substances. However, with massive bacterial colonization and high concentrations of poisons and metabolites in the biomass of the body, the sorption process occurs in all parts of the gastrointestinal tract.

Depending on the specific tasks, the optimal form and dosage of the sorbents should be selected. Psychologically, the most difficult reception of patients with granular forms of sorbents, and more readily accept well-crushed sorbents, for example in the form of pastes that do not taste and smell and do not injure mucous membranes. The latter is inherent in carbon fiber materials.

The most commonly used 3-4-times intake of enterosorbents (up to 30-100 g per day, or 0.3-1.5 g / kg body weight), but depending on the nature of the pathological process (for example, in acute poisoning) the necessary effect is easier achieve a single shock dose of the drug. In order to avoid sorption of drugs administered orally, the time interval from their administration to the use of enterosorbent should be at least 30-40 minutes, but nevertheless it is preferable to perform drug therapy parenterally.

Enterosorption is used in medicine to treat a wide range of acute and chronic diseases accompanied by toxicosis, which allows to increase the effectiveness of other types of treatment and reduce their volume, including extracorporeal methods of detoxification. Positive effect is noted in allergic diseases, bronchial asthma, psoriasis, as well as with various manifestations of atherosclerosis, acute and chronic liver diseases. The method allowed to improve the results of treatment of a number of surgical diseases (acute pancreatitis, purulent peritonitis), renal insufficiency, various infectious diseases, enterosorption favorably influenced the course of the wound process.

[7], [8], [9], [10]

The method of enterosorption in acute poisoning

Equipment	The probe for washing the stomach, intestinal lavage, enterosorbents
Preliminary preparation
Sorbent preparation	To introduce the sorbent through the intestinal canal channel into the small intestine, the granulated activated carbons are first ground to obtain a uniform fine powder. Next, a portion of this coal is taken and mixed with 2-3 parts of the vaseline oil until an emulsion is formed which is heated to 37 ° C
Recommended Techniques	Up to 80-100 g of sorbent inside in the form of a liquid suspension in 100-130 ml of water. Introduction of 80-100 g of sorbent in a liquid suspension through a probe after the end of gastric lavage. When enterosorption is combined with intestinal lavage, intestinal perfusion is interrupted and 100-200 g of the sorbent in the form of an emulsion, then continue the introduction of a saline enteral solution. When poisoning with poisons prone to enterohepatic circulation, 50-60 g of sorbent for the first injection, then 20 g of sorbent after 6-8 h
Indications for pimenia	Clinical moderate and severe acute oral poisoning by sorbing poisons Laboratory toxic concentrations of poisons in the biomedids (blood, urine washings from the stomach and intestines)
Contraindications	Not identified
Complications	Not identified