Hypotonic sodium chloride solution

Posted on by admin

/ Types of solutions

Solutions are homogeneous mixtures of two or a large number of substances (components), which are evenly distributed in the form of individual atoms, ions, molecules.

There are true, colloidal solutions and suspensions.

Table of contents:

True solutions are characterized by transparency, have small sizes of dissolved particles, and easily pass through biological membranes. Depending on the concentration of salts, there are three types of solutions: isotonic; hypertensive; hypotonic ;

1. Isotonic solutions have the same salt concentration as in blood plasma and the same osmotic pressure.

These include solutions with a salt concentration of 0.9%.

One of these solutions is saline solution - this is a solution of sodium chloride - NaCl 0.9%. In such a solution, water molecules will move into and out of the cell in equal quantities in both directions.

C cl = C solution C – salt concentration

In this solution, the cell retains all vital functions, carrying out the processes of respiration, reproduction, and metabolism.

Application of saline solution.

Inject saline solution through the mouth, intravenously, intramuscularly, subcutaneously, into the rectum:

in some diseases - severe prolonged diarrhea, cholera, uncontrollable vomiting, extensive burns, sodium chloride is released from the body in larger quantities than usual. Also, a lot of it is lost through sweat when working in hot shops. In such cases, its deficiency occurs in the body, which is accompanied by the development of a number of painful phenomena: spasms, convulsions, circulatory disorders, central nervous system depression;

in case of intoxication, blood loss, dehydration, high temperature

for washing the eyes and nasal cavity.

sodium chloride is an integral part of solutions used as blood-substituting (plasma-substituting) liquids.

2. H ypertonic solution (2%, 5%, 10%, 15%) is a solution in which the concentration of salts is higher than in blood plasma .

These include solutions containing more than 0.9% salts. If a cell is placed in such a solution, then water from the cell enters the environment, while the turgor (osmotic) pressure in the cell drops, the contents of the cell shrink, it loses its shape, and dehydration occurs. This phenomenon is called plasmolysis

The phenomenon of plasmolysis is reversible; if a cell is placed in a hypotonic solution, then in such a solution it will restore the volume and shape of the H 2 0 cell

A hypertonic solution is used for:

gargling, for baths, rubdowns;

Prescribed for constipation to empty the bowels.

in the form of compresses and lotions they are used in the treatment of purulent wounds, the wounds are cleansed of pus;

2 – 5% solutions are used for gastric lavage in case of silver nitrate poisoning;

used intravenously for pulmonary edema and internal bleeding.

3. Hypotonic solution is a solution that has a lower concentration of salts than in blood plasma. These include bi-distilled water and glacial melt water. If a cell is placed in a hypotonic solution, then water will flow into it from the solution, the osmotic pressure increases, and the cell swells. This phenomenon is called deplasmolysis.

Animal cells are quickly destroyed in such a solution because the membrane cannot withstand high osmotic pressure and ruptures. This phenomenon is called cytolysis . Special cases of cytolysis are the destruction of red blood cells - hemolysis , in which hemoglobin enters the blood plasma and colors it red, such blood is called varnish .

Plant cells in such a solution usually only swell, because In addition to the cytoplasmic membrane, they have a dense cell wall - a cellulose membrane. But, if plant cells are kept in a hypotonic solution for a long time, then they too are destroyed.

Hypotonic solutions are used as solvents for water-soluble drugs. Through pinocytosis, nutrients from the bloodstream, hormones, enzymes, and drugs enter the cells.

a) elodea leaf cells b) plasmolysis in elodea leaf cells (in 10% sodium chloride solution)

Suspensions, or suspensions, are turbid liquids whose particles are larger than 0.2 microns in size. During settling, suspended particles settle.

Colloidal solutions. If the particles have intermediate sizes from 0.1 to 0.001 microns, that is, too large to form a true solution, but also too small to precipitate, a colloidal solution arises (Greek co11a - glue). Since the diameter of protein molecules exceeds 0.001 microns, proteins form colloidal solutions and all protoplasm is a colloid. In colloidal solutions, huge total areas are created on the surfaces of particles

Water molecules are firmly connected to protein molecules by hydrogen bonds. The smallest particles of substances surrounded by water molecules form colloidal solutions - these are cytoplasm, karyoplasm, intercellular fluids. In a colloidal solution, a continuous phase is distinguished - the dispersion medium (water) and colloidal particles - the dispersed phase. Colloidal particles of protoplasm are most often protein molecules, because their sizes correspond to the sizes of colloidal particles.

Around the protein in a colloidal solution, aqueous or solvate shells (from the Latin solvare - to dissolve) are formed. Solvate bound water is firmly held by colloidal particles of proteins. Water molecules, creating shells around proteins, prevent the formation of large particles. This state is called dispersive (scattered, fragmented).

Dispersity (degree of fragmentation) is inversely proportional to the size of colloidal particles

Colloidal particles are, as it were, suspended in a dispersion medium, where a huge surface is created on which sedimentation, adsorption of substances entering the cell and the course of various biochemical reactions occur.

Colloidal solutions come in two states : in the form of a sol ( dissolved) and a gel ( jelly, more viscous ).

Gels disperse systems . In a gel , elongated protein molecules, in contact with each other, form a network frame filled with liquid.

Sols are colloidal solutions with particles that move freely. When protein molecules (colloidal particles) separate, the colloid becomes a sol .

These processes are reversible and occur continuously in the cell. When a muscle contracts, the sol quickly turns into a gel and vice versa . When pseudopodia are formed in amoeba, a transition of the gel to sol is observed

This transition from one state to another can be observed in a solution of gelatin, which when heated is liquid (sol), and when cooled it becomes gelatinous (gel).

The colloidal state determines the viscosity. Viscosity increases and dispersion decreases; for example, when cells are damaged, the sizes of colloidal particles become larger due to swelling and aggregation.

THE CONCEPT OF DISPERSE SYSTEMS, COLLOIDAL AND CRYSTALLINE STATES OF PROTOPLASMA

Protoplasm is characterized by a number of physicochemical properties. This is due to the fact that it is a complex combination of colloidal solutions of protein and other organic substances with true solutions of salts and a number of inorganic compounds. Protoplasm is a stable hydrophilic colloid. The colloidal state of protoplasm determines its viscosity. In most cells, the consistency of the cytoplasmic matrix exceeds the viscosity of water by no more than 5-10 times, but in some cases it can be significantly higher. The viscosity of protoplasm depends on metabolic processes in cells. Thus, it increases when the cell is damaged, and in eggs - after fertilization. During cell division, a rhythmic change in the viscosity of protoplasm is detected. Blood viscosity changes depending on the physiological and pathological state of the body.

Previously, the only physical state of protoplasm was considered colloidal. But recently it has been discovered that a number of cellular structures are liquid crystals. Liquid crystals, unlike real crystals, which have a regular alternation of their constituent molecules in three dimensions, are ordered only in two dimensions. Liquid crystals occupy an intermediate position between liquids and crystals. On the one hand, like liquids, they have fluidity and can merge with each other; on the other hand, like crystals, they are characterized by anisotropy, that is, their strength, electrical conductivity and a number of other properties are not the same in different directions. The characteristics of liquid crystals are important for understanding a number of life processes: they sometimes exhibit the ability to move, and they often divide by budding. Apparently, the liquid crystalline state of a number of cellular structures ensures their greater lability (mobility, variability).

Lipids have a great ability to form liquid crystals. The liquid crystalline structure is found in sperm, red blood cells, cells of the nervous system and nerve fibers, rods and cones of the retina.

To continue downloading, you need to collect the image:

Source: http://studfiles.net/preview//

Isotonic saline solution

Many have heard the concept of “isotonic solution”; its varieties are widely used in medical practice. One of the most famous is sodium chloride solution. It is most often used in therapy and for the prevention of upper respiratory tract diseases.

Properties and types

Isotonic is an aqueous solution in which the osmotic pressure is the same as in body fluids (blood plasma, tear fluid, lymph). It is used to eliminate intoxication in the body and in the treatment of many pathologies. Due to its isotonicity, the solution can be administered into the body, because, unlike hypertonic and hypotonic solutions:

  • Does not cause cell damage.
  • Does not cause pain.
  • Does not pose a health hazard.

Most often, two types of isotonic solutions are used: sodium chloride 0.9% and glucose 5%. They are considered simple because they correspond only to osmotic pressure. Complex solutions, in turn, are more physiological, since they have a salt composition, buffer properties and an active reaction almost the same as body fluids. It would be correct to call them saline solutions, and not simple ones: sodium chloride and glucose, as we are used to.

Isotonic solutions (Ringer, Ringer-Tirode, Ringer-Locke, Ringer-Krebs, Acesol, Chlosol, Lactasol, Trisol, Disol), more physiological in composition.

Each of them is prepared according to all the rules, the necessary salt is added gradually after the previous one has dissolved. Only distilled water is used for these purposes.

Application

Isotonic solutions are used for various purposes, which is why they are so famous. The following main areas for application are identified:

  1. Infusion therapy is used for dehydration to restore water balance in the body after diarrhea, poisoning and large blood losses.
  2. Removal of toxic substances, infections, used as a detoxification agent.
  3. Treatment of the mucous membranes of the nose, eyes and serous cavities (in the form of washing liquids, drops).
  4. Inhalation therapy is used as a solvent for drugs, for diseases of the respiratory system and as an independent remedy.
  5. Washing wounds and bruises.
  6. Dissolution of drugs.

Administration into the body occurs intravenously (often using droppers), subcutaneously and in enemas. 1.5–2 liters of isotonic solution are allowed per day, in some cases, for example, in severe conditions up to 8 liters.

This infusion therapy is administered with caution and closely monitored. Since an excess of isotonic solution in the body can lead to a significant deterioration in human health.

Use for ENT diseases

Most often, isotonic sodium chloride solution is used for sinusitis, frontal sinusitis, rhinitis, rhinosinusitis and rhinopharyngitis. This product is widely used for nasal hygiene, as it has antibacterial and healing properties. This solution is suitable for use by pregnant, nursing mothers and infants. It can be found in pharmacies in the form of aerosols, vials, bottles and ampoules.

Sodium chloride is used for problems with nasal breathing in the form of:

  • Drops. Drop 1-2 drops of solution for children, 3-4 for adults. 3 procedures can be performed per day. To make it convenient to use, you can pour the purchased solution into a bottle of nasal drops; it must be clean.
  • Washing. After filling a syringe with a solution, inject it into the nostril, keeping your mouth open. It is better to do this over a basin or sink. Repeat the procedure until nasal breathing normalizes and all the accumulated mucus comes out. If there is congestion, you should do 1-2 rinses per day. For preventive purposes, to moisturize the nasal mucosa, it is recommended to carry out these manipulations 1–2 times a week, since the air in rooms is often dry, and this leads to crusts and discomfort.
  • Inhalations. The procedure is performed with sodium chloride alone or diluted with other medications. 3-4 ml of solution is poured into the inhaler, 3-4 procedures are performed per day, for children under 2 years old the number of manipulations should be no more than 2.

Sodium chloride solution is quite safe, but if you often have nosebleeds, have neoplasms, acute otitis media or complete obstruction of the nasal sinuses, you should avoid using it.

Cooking at home

In order to moisturize, remove thick secretions and rinse the nasal mucosa, an isotonic saline solution is used. It is easy to prepare at home and does not require much knowledge or effort. After all, salt and water can be found in the kitchen of any housewife. This solution can be used for nasal hygiene and gargling, and is also suitable for enemas. But you should not use the product for washing wounds, as it is too concentrated for application to open areas of skin.

To prepare the solution, you will need 1 tsp. purified table salt and 1 liter of warm boiled water. If you dilute sodium chloride in liquid, you get a concentration of 1%, and this practically corresponds to the concentration of salts in the body, which is 0.9%.

But if you take a heaping teaspoon of the powder, you can overdo it and end up with a hypertonic solution. Also, if you add a little less salt, you will get a hypotonic solution that is absorbed very quickly, so it is not recommended for rinsing and using as drops. If you have a kitchen scale, the task is simplified, since you only need to weigh out 9 g of purified salt to get the correct composition.

Remember, an isotonic saline solution prepared at home can be stored for no more than a day and only in a glass container with a non-metallic lid.

Salt and water interact well with each other, complement the action and are indispensable assistants in medicine. Hypertonic and isotonic solutions stop bleeding, treat wounds and fight purulent discharge. They are similar to each other and at the same time differ in concentration and methods of application. Solutions vary in salt content and are used for different medical purposes.

Isotonic solution

It is also called physiological, and the whole point is the same concentration of sodium chloride salts with human blood plasma. This solution has the same osmotic pressure, thanks to this action it helps cells and tissues not to be destroyed. In case of dehydration, this composition saturates and nourishes the body, returning moisture to all structures and systems. It is administered in various ways, through the mouth, nose, intravenously, intramuscularly and subcutaneously.

The solution is most often used by specialists for the following purposes:

  1. To replenish the water balance after vomiting, diarrhea, bleeding or intoxication of the body.
  2. To remove waste, infection or other toxins after poisoning.
  3. In the form of inhalations for problems with the respiratory system.
  4. For treating wounds, bruises or damage to tissue integrity.
  5. As a basis for various medications.

Isotonic or saline solution is easy to prepare yourself at home, but can only be used for external use. To do this you will need 1 liter of boiled water and 1 tsp. salt. The composition is useful for enemas or gargling, but it is too concentrated for treating open wounds.

Low concentration solution

It contains less salt, so it has a lower osmotic pressure. If a hypotonic solution is applied orally, it will be absorbed by the tissues.

When a large amount of a substance is introduced, lysis can occur, that is, destruction of the cell itself, which is very dangerous and even fatal for the human body. Used in narrow areas, mainly for anesthesia, in other cases it is useless.

Highest salt content

A hypertonic solution is the most concentrated; its osmotic pressure is 10% greater than that in blood plasma. Thanks to its repellent properties, it removes excess moisture from the body, which helps relieve tissue swelling. If the composition comes into contact with cells and tissues for a long time, they become dehydrated and eventually die. It has an antimicrobial effect, which is why it helps fight infections in wounds.

Used in many ways, namely:

  • For gargling with sore throat and other inflammatory processes in the nasopharynx.
  • Applying bandages and compresses to purulent or open wounds.
  • For tissue swelling.
  • In gynecological practice.
  • Concentrated solutions are used for severe intestinal or pulmonary bleeding.
  • A 5% solution can be used to cleanse the intestines using an enema.
  • Used in water procedures.
  • Used in cosmetology to strengthen the nail structure, as well as hair, in the fight against fungus.

You can prepare any solutions yourself; you just need 1 liter of boiled water and 3 tablespoons of salt. Try to use it immediately on the first day of preparation, and do not overdo it with sodium chloride, otherwise it can lead to serious tissue damage.

Differences

Many people do not see the difference between these solutions at all, but it exists and it is necessary to know it. After all, using a self-selected bottle in a pharmacy for other than its intended purpose can harm your body and lead to cell lysis.

Isotonic solution and hypertonic solution - both options are used to treat humans, if one is most often created for internal administration in order to saturate the body with moisture. The second one is considered a sorbent and helps remove water and toxins from body tissues.

Of course, they are distinguished directly by different salt content, osmotic pressure and methods of application. When used correctly, they have a beneficial effect on a person and remain indispensable assistants in many situations, as well as improvised means for the prevention of many diseases at home.

Useful tips and information

Regardless of the concentration and method of application of the compositions, first of all, permission and consultation of a doctor is required. In small babies or people with kidney disease, salts are poorly excreted from the body, and this can lead to negative consequences. Therefore, it is necessary to undergo tests and conduct an ultrasound examination of the abdominal cavity.

If you need to infuse an isotonic solution, you should purchase a sealed bottle and connect it correctly so that no air gets in. Nursing staff have this knowledge; doing this yourself at home is very dangerous, because you may not get into the vein, all the liquid will be released into the tissue, leading to swelling and other problems.

It is also important to take only sterile solutions and use them immediately after uncorking, otherwise contamination may occur, which will indicate the complete unsuitability of this reagent.

How to use factory blanks correctly:

  1. The package is opened immediately before use, only this guarantees sterility.
  2. Before installing the IV, check for holes or other defects. If such damage is present, the bottle should be disposed of along with the solution in it.
  3. Pay attention to the color and turbidity; if there is any suspicion, it is also not recommended to take it for treatment.
  4. Under normal circumstances, mount the saline bottle on a stand, open the cap, and insert the needle.
  5. Any solution must be administered slowly to avoid problems with the general condition of the patient.

By adhering to these basic rules, you can protect your body from infection.

Thanks to different concentrations of solutions, many therapeutic and preventive actions can be carried out. But before self-medicating, it is better to consult your doctor.

Isotonic solutions are aqueous solutions that are isotonic to blood plasma. The simplest solution of this type is a 0.9% aqueous solution of sodium chloride (NaCl) - the so-called physiological solution (“saline”) . This name is very conditional, since “saline solution” does not contain many substances (in particular, potassium salts) necessary for the physiological activity of body tissues.

Types of isotonic solutions

Other examples of isotonic solutions that have a more physiological composition are:

  • Ringer's solution
  • Ringer-Locke solution
  • Ringer's solution - Tyrode
  • Krebs-Ringer solution,
  • Disol, Trisol, Acesol, Chlosol
  • Lactasol

Preparation of saline solution

When preparing solutions, salts are added sequentially, each subsequent salt is added only after the previous one has dissolved. To prevent precipitation of calcium carbonate, it is recommended to pass carbon dioxide through the sodium bicarbonate solution. Glucose is added to solutions immediately before use. All solutions are prepared using fresh distilled water distilled in glass equipment (metals have a significant effect on the vital functions of tissues).

Action

Sodium chloride is found in blood plasma and tissue fluids of the body (concentration of about 0.9%), being the most important inorganic component that maintains the appropriate osmotic pressure of blood plasma and extracellular fluid. Sodium chloride enters the body in required quantities with food. Deficiency can occur in various pathological conditions accompanied by increased excretion in the absence of compensating intake from food. Increased loss of sodium and chlorine ions occurs with prolonged severe cholera-like diarrhea, uncontrollable vomiting, extensive burns, and hypofunction of the adrenal cortex. When the concentration of sodium chloride in the blood plasma decreases, water passes from the vascular bed into the interstitial fluid and blood thickening develops. With a significant deficiency, smooth muscles spasm and convulsive contractions of skeletal muscles appear, the functions of the nervous and cardiovascular systems are disrupted. Sodium chloride solutions are widely used in medical practice and, depending on the concentration, are divided into isotonic (0.9%) and hypertonic. A solution (0.89%) of sodium chloride is isotonic with human blood plasma and is therefore quickly cleared from the vascular bed, only temporarily increasing the volume of circulating fluid, so its effectiveness against blood loss and shock is insufficient. Hypertonic solutions (%) are used intravenously and externally. When applied externally, they promote the secretion of pus, exhibit antimicrobial activity, and when administered intravenously, they increase diuresis and replenish the deficiency of sodium and chlorine ions.

Indications

Saline solutions are used as a detoxification agent, to correct dehydration, to dissolve other medications, and less often as a blood substitute or to rinse contact lenses.

Acute effects

Hypernatremia—a blood sodium level above 145 mEq/L causes thirst, and due to decreased brain cells, can cause confusion and muscle spasms. High levels of sodium chloride can lead to seizures and coma. Death can be caused by ingestion of large quantities of salt (about 1 g per kg body weight) or can also be caused by excessive use of salt solutions as an emetic (usually after poisoning is suspected), when accidentally used instead of sugar in foods . Excessive intravenous administration of saline (0.9% NaCl) may lead to undesirable clinical consequences. One liter of saline solution contains 9 g of salt, which is about twice the recommended daily requirement. If a patient becomes thirsty after saline administration, this means that he already has an excess amount of Na+ in the body, i.e. he received too much salt.

Restrictions

In case of impaired renal function, high blood pressure and heart failure, large volumes of saline are prescribed with caution.

Mode of application

The isotonic solution is administered intravenously, subcutaneously (due to the large volume of the injected solution - into the outer surface of the thigh) and in enemas.

see also

  • Collins solution

Notes

Literature

  • Mashkovsky M.D. Medicines. — 15th ed. - M.: Novaya Volna, 2005. - P. 681-682. — 1200 s. — ISBN03-7.

Bertrand Guidet, Neil Soni, Giorgio Della Rocca, Sibylle Kozek,

Benoot Vallet, Djillali Annane and Mike James

Abstract

In this review, dedicated to the comparison of balanced and isotonic (crystalloids and colloids) saline solutions for infusion, we will try to resolve all the contradictions associated with this topic. Methods for changing the acid-base balance based on the choice of solutions will be described. Key concepts will be defined: hyperchloremic hypervolemic acidosis (a more correct term than hypervolemic acidosis or metabolic hyperchloremia, corresponding to the Henderson-Hasselbach and Stewart equations), isotonic saline and balanced solutions. The review concludes that hyperchloremic hypervolemic acidosis is a side effect of large-volume infusion therapy with isotonic crystalloid solutions. This is a short-term and reversible effect, the development of which can be easily avoided by replacing some of the crystalloids with colloids (regardless of the composition). Reliable clinical information on the impact of this side effect on renal function, coagulation system, blood loss, the need for blood transfusion and gastrointestinal function has not been obtained. Given the long history of the use of isotonic solutions (colloids and crystalloids), the paucity of data regarding the adverse effects of hyperchloremic hypervolemic acidosis, and the literature on the effectiveness of the use of balanced solutions, at this time we cannot make any specific recommendations for the use of balanced colloid solutions for infusion.

Introduction

Normal salt solutions have been used in medical practice for more than 50 years as intraoperative, resuscitation and maintenance infusion therapy. Although in essence they are neither normal nor physiological, they still remain a kind of standard against which any other drugs are compared. Recently, quite a bit of attention has been paid to so-called balanced solutions, such as lactated Ringer's solution and its later derivatives. In addition to colloids in an isotonic salt environment, their solutions in balanced electrolyte environments are very actively developing.

As many would expect, excessive use of saline infusion solutions often leads to the development of hyperchloremic acidosis, which is considered a side effect of their use. There is currently debate about the pathogenic impact of this phenomenon on the body, with many arguing that it is extremely small. It was assumed that the use of balanced solutions would help avoid its development altogether.

This type of acidosis has been described in some detail in the British Consensus Guidelines on fluid therapy in surgical patients. This manual makes it absolutely clear that unbalanced crystalloid solutions should be used rather than saline solutions; however, there are no specific recommendations regarding the choice of standard or balanced colloid solutions. Once published, these guidelines immediately provoked a strong reaction from the medical community. In a column by the editor-in-chief of the British Medical Journal, Liu and Finfer stated: “Although the administration of normal saline solutions may lead to the development of hyperchloremic acidosis, we still cannot say that it causes any harm to the health of the patient. Although the recommendations given should not harm patients, they may not bring any benefit.”

Other authors have described the physiological effect of acidosis. Handy and Soni noted that: “Over the period of use of normal saline solutions, which is at least 50 years, no significant pathogenic effects associated with infusion therapy have been observed.” Liu and Finfer added that: “Under pressure from published guidelines, many clinicians will be forced to make changes to fluid therapy regimens that may not be cost-effective in the future and may be detrimental to patient health. We are inclined to say that until reliable primary data are obtained, guidelines should refrain from making such radical statements, and clinicians should be guided by generally accepted standards when selecting infusion therapy."

Taking into account the obvious contradictions that arose in the interpretation of the available data, we consider their revision to be quite appropriate and necessary. To do this, it is necessary to collect and analyze all available reviews and articles published in the literature regarding the comparison of balanced and isotonic (both colloid and crystalloid) solutions for infusion, and develop scientifically sound premises, which will become the basis for the creation of guidelines and recommendations.

Acid-base balance: Henderson-Hasselbalch vs. Stewart

In critically ill patients, determining the underlying mechanism of acid-base regulation is vital to selecting appropriate therapy. At the moment, the main way to describe these processes in clinical practice is the Henderson-Hasselbalch equation:

pH = pK1′ + log / (S × PCO2)

This equation describes a method for determining plasma pH through calculations that take into account the partial pressure of CO2, the concentration of bicarbonate ions, the theoretical plasma carbonic acid dissociation constant (pK), and the solubility of carbon dioxide in plasma. The severity of acidosis is expressed as a deficit of the main volume, that is, the amount of alkali (or acid) or acid that must be added to 1 liter of blood in order for its pH to become equal to 7.4 at a partial pressure of carbon dioxide of 40 mm Hg. . The main effect of isotonic saline administration is a decrease in bicarbonate concentration due to an increase in plasma volume. A decrease in albumin concentration also plays a minor role, for a similar reason. Therefore, this disorder is considered to be a hypervolemic acidosis associated with a basal volume deficiency due to an increase in chloride concentrations.

In 1983, Stewart took a different approach to the study of acid-base balance, which took into account changes in a number of variables that independently regulate plasma pH. He proposed that plasma pH is influenced by three independent factors: PCO2, strong ion difference (SID) (represents the charge difference between the strong cations (sodium, potassium, magnesium and calcium) and anions (chloride, sulfate, lactate and others) of the plasma) and the sum of all negative charges of weak plasma acids (Atot) (representing the total concentration of stable buffers, albumin, globulins and phosphate). More details can be found in a recent review by Yunos et al. The Stewart equation can be written in a form similar to the Henderson-Hasselbalch equation:

pH = pK1′ + log / (S × PCO2)

At normal plasma pH, albumin carries a weak negative charge, which can affect the buffering of hydrogen ions. The same statement is true for phosphates, but their concentration is so low that they do not have a significant buffering effect. Accordingly, the Stewart equation takes into account the role of albumin, phosphate and other buffers in the formation of acid-base balance. With its help, it is possible to identify six reasons for the violation of this balance, while the Henderson-Hasselbalch equation can only take into account four of them. Moreover, this approach provides a clearer explanation regarding the role of chloride in the formation of acid-base balance.

The RSI of an isotonic saline solution is zero; infusion of it in large quantities will lead to a “dilute” of the RSI of the plasma and a decrease in the pH value. Thus, metabolic hyperchloremic acidosis is a decrease in plasma RSI associated with an increase in chloride concentration. Moreover, Stewart's equation shows that infusion of isotonic saline will also dilute albumin and decrease Atot, leading to an increase in pH. According to the equation, a saline solution with an RSI of 40 mEq/L will lead to the development of metabolic alkalosis. As Morgan and Venkates showed, to eliminate this type of effect, a balanced solution should have an RSI of 24 mEq/L. It should be noted that balanced solutions containing organic anions (for example, lactate, acetate, gluconate, pyruvate or malate) in vitro have an RSI of 0, as do isotonic saline solutions. In vivo, the metabolism of these anions increases the RSI and decreases the osmolarity of the solution.

The Stewart equation, despite its logic, in its original form still remains difficult to understand, but in a simplified form it can be used to create a graphical diagram of acid-base equilibrium. In this case, only the most important substances affecting the balance are taken into account: sodium, potassium, calcium and magnesium, minus chloride and lactate. In this case, the theoretical value of RSI will be as follows (see Figure 1):

Graphic diagram of the Stewart model. Charge balance in blood plasma. The difference between the theoretical strong ion difference (RSIa) and the practical one (RSIe) is the strong ion anion gap (SAI), which is formed due to unmeasured anions. AGI should not be confused with anion gap (AI). An adjusted AI can be calculated to account for variations in albumin concentration.

Borrowed and adapted by Stewart.

Both approaches to describing the acid-base balance are the same from a mathematical point of view, but differ significantly in their concept. Both are not axiomatic. The disadvantage of Stewart's approach is that bicarbonate is introduced as a variable, while from a physiological point of view it is clear that it plays a critical role in maintaining balance, and its concentration is regulated by the kidneys. The Henderson-Hasselbalch approach, in contrast, focuses on bicarbonate, and therefore more accurately represents the actual physiological process. From the point of view of the dilution concept, during massive intravenous infusion of isotonic saline solutions, metabolic acidosis is a consequence of a decrease in bicarbonate concentration due to its dilution. The Stuart approach denies this theory and explains this phenomenon by a decrease in RSI. Some authors make claims against this purely technical approach from the point of view of the chemistry of the process. In short, the Stewart equation, although correct from a mathematical point of view, still does not describe the true mechanics of the process. At the same time, the use of this approach for clinical quantitative and qualitative classification of acid-base balance disorders can help to understand the principles of implementation of some complex disorders.

When using another approach, intracellular erythrocyte and intercellular buffers are not taken into account. While they play an important role in the formation of acid-base balance and, therefore, must be taken into account, especially when it comes to the infusion of isotonic saline solutions (Figure 2).

Plasma bicarbonate concentration and relative hemoglobin concentration in the field of acute hemodelution in different groups of patients. Concentration (mmol/l) of bicarbonate (HCO3-) and relative concentration of hemoglobin (Hb) (%) after normovolemic hemodelution in different groups of patients. A comparative analysis of theoretical (white squares) and actual (black circles) concentrations of actual indicators of bicarbonate HCO3- (upper curve) is presented, consisting of the calculated values ​​of HCO3- (black triangles) when diluting plasma, plus the increase due to plasma proteins (PP), red blood cells (E), and intercellular fluid (ICF), taking into account the appropriate buffers.

Borrowed and adapted from Lang and Zander.

The most important question remains the cause of acidosis. It can be a consequence of both physiological processes and iatrogenic effects. The whole difficulty lies in separating the pharmacological component of this phenomenon. For example, acidosis may result from organ distress due to organ hypoperfusion or hypoxia (eg, shock, ketoacidosis, or renal dysfunction). All of them can trigger large-scale physiological processes that are considered more likely to be a consequence of acidosis than as its cause. Correction of the pathological process may lead to compensation of acidosis, while correction of the acidosis itself is unlikely to lead to compensation of the pathological process. This is why understanding the mechanism of acidosis is so important.

Definitions

In this article, we used the following terms to more accurately characterize processes and describe solutions.

Hypervolemic hyperchloremic acidosis

This term is used instead of the previously used hypervolemic acidosis and hyperchloremic metabolic acidosis, to emphasize the contribution of both theories (Henderson-Hasselbalch and Stewart). In reality, most articles on metabolic hyperchloremic acidosis do not take the RSI into account and only consider the underlying volume deficit and chloride ion concentration.

Isotonic saline solutions

This term describes the main property of 0.9% salt solutions. The solution is neither normal nor abnormal nor unbalanced. Sodium and chloride ions are partially active, the osmotic coefficient is 0.926. The actual osmolality of a 0.9% saline solution is 287 mOsm/kg H2O, which is exactly the same as plasma osmolality.

Balanced solution

Most often, the term is used to describe various solutions of electrolytes close in composition to plasma, while balanced solutions are neither physiological nor adapted to plasma. Table 1 shows the composition of commonly occurring crystalloids, and Table 2 shows the composition of colloids.

Electrolyte composition (mmol/l) of the most common crystalloids

*Plasma-Lyte® from Baxter International (Deerfield, IL, USA). Sterofundin® from B Braun (Melsungen, Germany).

Electrolyte composition (mmol/l) of the most common colloids (part 1)

Electrolyte composition (mmol/l) of the most common colloids (part 2)

HES hydroxyethyl starch.

Gelofusine®, Venofundin® and Tetraspan® from B Braun (Melsungen, Germany).

Plasmion®, Geloplasma®, Voluven® and Volulyte® from Fresenius-Kabi (Bad Homburg, Germany).

Hextend® by BioTime Inc. (Berkeley, CA, USA). PlasmaVolume® from Baxter International (Deerfield, IL, USA).

Quantitative effect on acid-base balance indicators from infusion of isotonic saline solutions

The effect of administering isotonic saline solutions has been well described by Rehm and Finsterer for patients being prepared for abdominal surgery. Each patient received 40 ml/kg/hour of 0.9% isotonic saline, for a total of approximately 6 liters over 2 hours. The theoretical RSI value decreased from 40 to 31 mEq/L, the chloride ion concentration increased from 105 to 115 mmol/L, and the base shift decreased by approximately 7 mmol/L. These data clearly illustrate the development of hypervolemic hyperchloremic acidosis in response to the administration of large amounts of isotonic solution. Before assessing the clinical significance of this effect, the contribution of colloids and crystalloids to its development should be calculated.

Several studies have shown biological effects from crystalloid administration. Boldt et al provide an interesting illustration of the effects of high dose crystalloid administration (isotonic saline and lactated Ringer's). The study involved patients being prepared for abdominal surgery; they received 8 liters of crystalloid during surgery and then another 10 liters in the first 48 hours after surgery (Table 3); as a result, each patient received 18 liters of isotonic saline or lactated Ringer's solution. As shown in Table 3, these ultra-high doses of crystalloids resulted in only minimal short-term effects on acid-base balance: a reduction in base shift of 5 mmol/L over 1-2 days.

Total infusion volume and diuresis: effect on chloride concentration and base shift

RO, intensive care unit.

A hypertonic solution of table salt is an active sorbent that absorbs liquid from nearby tissues. Its use is quite wide - from diluting certain medications to using it at home to treat a number of diseases.

This sorbent absorbs liquid from nearby tissues, that is, body cells. Leukocytes, red blood cells and tissue cells are not damaged. Hypertonic solution of table salt has the following medicinal properties:

  • Anti-edematous effect on treated tissues. Extraction of excess fluid from cells occurs due to the higher concentration of salt in the solution compared to the intercellular fluid.
  • The hypertonic solution has an anti-inflammatory effect, removing secretions or pus from the affected tissues, organs or wounds. Salt is able to remove all products of the inflammatory process.
  • Along with excess fluid, pathogenic microorganisms are also removed from the affected tissues, which promotes rapid recovery.

Based on the above advantages, hypertonic solution at home has found its wide application. But it is necessary to do it correctly, and therefore you should strictly follow the rules and proportions of ingredients.

How to prepare saline hypertonic solution

Every pharmacist knows how to prepare a hypertonic solution of table salt. Making it yourself will not be difficult. To do this, follow the instructions:

  1. Boil 1 liter of water (mineral, purified, distilled) and cool to room temperature.
  2. There is approximately salt per liter of water. A larger amount will make the solution aggressive and may ultimately harm the body. Add a precisely measured amount of salt to boiled water. The amount of salt is usually calculated based on the specific concentration of the resulting solution that is needed.
  3. Stir the salt until completely dissolved.
  4. The resulting solution is used within an hour, as after that it becomes unsuitable for use.

A hypertonic solution is used at home as inhalation, for washing, rinsing, under a bandage, and so on. For the bandage you will need loose cotton fabric or gauze, which is folded into 8 layers.

The prepared bandage is placed in a saline solution for a couple of minutes, then wrung out, and then applied to the wound or skin in the area of ​​the diseased organ. The bandage is left in place for a period of time determined by the goals of treatment.

Typically the exposure period is from 1 to 12 hours. When the gauze dries quickly, the compress changes. The course lasts from a week to 10 days. Usually visible results are observed after the second procedure.

Hypertonic solution aquamaris

In fact, a homemade solution cannot always be compared with a pharmacy solution. In the latter, in addition to sodium chloride, other useful substances and microelements are also added.

So, you can buy a hypertonic solution of Aquamaris at the pharmacy. This is a saline solution sold as a spray. It allows you to rinse the nasal and throat cavities.

Moreover, it is not only therapeutic, but also an excellent prophylactic agent that allows you to cope with acute respiratory viral infections and other similar diseases.

With the help of this drug, it is also possible to cope with allergic rhinitis, while increasing immunity and resistance not only to allergens, but also to viruses, bacteria, and so on. This hypertonic solution can be used either separately or in complex treatment.

Healing with Aquamaris occurs due to a unique base - natural water of the Adriatic Sea. It contains in ideal proportions the amount of chemical elements necessary to activate the immune system. The bactericidal property of the product allows you to quickly cope with pathogenic microorganisms.

Aquamaris preparations are divided into two categories - isotonic solution and hypertonic solution. The first option contains approximately 0.9% sodium chloride. The second contains more salt.

These solutions act differently and are prescribed depending on age, symptoms and disease. For example, an isotonic solution is more used in the treatment of children. Frequency of use also depends on age.

When is this solution used?

We learned earlier how to prepare a saline hypertonic solution. Its range of applications is wide. Doctors use it in their practice in such cases as:

  • Joint pathology;
  • Abscess of internal organs;
  • Chronic appendicitis;
  • Rhinitis;
  • Headaches and migraines;
  • Osteochondrosis;
  • acute respiratory infections, acute respiratory viral infections with severe cough;
  • Asthma;
  • Bronchitis;
  • Angina;
  • Diseases of the female genital organs;
  • Hematomas;
  • Depressive states;
  • Edema;
  • Diseases of the endocrine system;
  • Gastrointestinal diseases;
  • Damage to muscles, bones, mechanical ligaments;
  • Malignant and benign neoplasms.

A variety of purulent wounds, dermatitis, ulcerations, burns and bacterial skin lesions are also treated with this solution. In such cases, compresses are considered the most effective. Also, a hypertonic solution is an excellent remedy for insect and animal bites, as well as the effects of frostbite.

Types of salt solutions and their use

We wrote earlier that there are such varieties as hypertonic solution and isotonic solution. In the first case, the salt concentration is much higher. The isotonic solution is more gentle, and therefore is usually used when treating children.

This is explained by the fact that in children, the mucous surfaces, like the skin, are very delicate, and therefore a strong saline solution can damage the surface of the treated area, which can in turn lead to a deterioration in health. Therefore, an isotonic solution simply replaces fluid in the cells, healing them

A hypertonic solution is more saturated, since for an adult organism its effect only brings benefits, without causing harm to the integument. Its use is wider than that of the isotonic one and is used as a compress, as an inhalation, and as a means for washing and rinsing the nose and throat.

There is also a hypotonic solution, in which the content of substances is much lower than in an isotonic solution. Its action is directed in the opposite direction when compared with a hypertonic solution. In particular, this type of solution compensates for the lack of fluid in the cells by releasing fluid.

When is this solution used?

A hypertonic solution is used in cases where there is a need to remove pathogens, secretions or pus from affected tissues, as well as to reduce inflammation or swelling. Thus, the use of a hypertonic solution of table salt is necessary for infectious diseases of the skin, diseases of the nasopharynx, joint diseases, injuries, gynecological diseases, and so on.

The treatment process usually takes from 7 to 12 days. If you also use medications prescribed by a doctor to treat a specific illness or injury, then recovery occurs many times faster.

Purulent wounds are especially effective in treating. A bandage soaked in the solution and wrung out is applied to the affected areas. Fresh hypertonic solution is used for each dressing. You need to keep the bandage on for about an hour. If it dries out, it must be moistened.

How to make it at home?

At home, a hypertonic solution can be made according to the above recipe. The salt content in the solution should be no more than 10%. At a higher concentration, nearby vessels are damaged, which can burst, causing pain and worsening the condition of the wound. The ideal salt content in the solution is 8-9%.

At home you can make baths, rubdowns, lotions using a 1-2% solution. A solution with a concentration of 2 to 5% can be used for gastric lavage.

If the poisoning is silver nitrate, then such a solution converts the substance into non-toxic and insoluble silver chloride. An enema can be done with a 5% solution. A 10% solution is used for intravenous administration, but this is the work of medical workers.

Hypertonic solution Quix

Kwix hypertonic solution is also purchased at the pharmacy, like Aquamaris. This product is created based on water from the Atlantic Ocean, in which the salt content is 2.6%. In addition, the solution contains useful microelements that have a healing effect on the body.

Quix has an anti-edematous effect, causing a change in the concentration of osmotic pressure. Excess fluid from the nasal passages is removed along with excess solution. There is also a mucolytic effect, which increases the effusion of fluid from the intercellular space, taking with it microbial and allergic particles.

Hypertonic solution for inhalation

A hypertonic solution for inhalation is also called isotonic, since in this case it is better to use a lower concentration of salt in the solution so as not to damage the respiratory organs. A sterile solution with a concentration of 0.9 to 4% sodium chloride in water is used for inhalation.

The most gentle, naturally, is 0.9%. More concentrated - 2%. It helps cleanse the nasal cavity of purulent and mucous contents. Higher concentrations are used only after a doctor’s prescription, and very rarely. Cases for use: analysis of induced sputum with difficulty coughing.

Hypertonic solution can be purchased at a pharmacy. The price largely depends on the popularity of a particular pharmaceutical brand. So Aquamaris costs about 200 rubles. Quicks costs respectively from 260 rubles. The compositions of such products differ in small details, but the main effect is the same.

Making a hypertonic solution at home for rinsing is correspondingly easier and cheaper, although it is quite difficult to maintain the exact proportions. When it comes to treating children, we still recommend purchasing a special product that will not harm the child’s body.

Tatyana, 45 years old: “I often suffer from purulent sore throats. A hypertonic solution with the addition of a couple of drops of iodine per glass helps a lot - no more. Everything goes away in two days.”

Victor, 56 years old: “All my life I have been rinsing my nasal passages with saline solution every day. I get a runny nose once every decade. Excellent prevention that won’t require you to spend a lot of money – if only you have the time and desire.”

Source: http://medic-03.ru/izotonicheskiy-solevoy-rastvor/