Infusion therapy

Infusion therapy is a method of parenteral supply of the body with water, electrolytes, nutrients and medicines.

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Infusion therapy: goals and objectives

The purpose of infusion therapy is the maintenance of the body's functions (transport, metabolic, thermoregulatory, excretory, etc.), which are determined by the HEO.

The objectives of infusion therapy are: 

• ensuring the normal volume of water spaces and sectors (rehydration, dehydration), restoration and maintenance of the normal volume of plasma (volumoreconstruction, hemodilution); 
• restoration and maintenance of HEO; 
• restoration of normal blood properties (fluidity, coagulability, oxygenation, etc.); 
• detoxification, including forced diuresis; 
• long and uniform administration of medicines; 
• the implementation of parenteral nutrition (PP); 
• normalization of immunity.

Types of infusion therapy

There are several types of infusion therapy: intraosseous (limited, the possibility of osteomyelitis); intravenous (main); intraarterial (ancillary, for bringing drugs to the focus of inflammation).

Variants of venous access:

• puncture of the vein - is used for non-long infusions (from several hours to days);
• Venesection - if necessary continuous administration of drugs for several (37) days;
• catheterization of large veins (femoral, jugular, subclavian, portal) - with proper care and aseptic provides infusion therapy lasting from 1 week to several months. Plastic catheters, disposable, 3 sizes (0, 6, 1 and 1.4 mm in external diameter) and 16 to 24 cm long.

Infusion therapy can be considered intermittent (jet) and continuous (drip) introduction of pores.

For jet injection of drugs used syringes ("Luer" or "Record"), made of glass or plastic; Preference is given to disposable syringes (the probability of infection of children with viral infections, in particular HIV and viral hepatitis, decreases).

Currently, systems for drip infusion therapy are manufactured from inert plastics and are intended for single use. The rate of administration of p-rods is measured in drops per minute. It should be borne in mind that the number of drops in 1 ml of p-ra depends on the size of the drip in the system and the force of the surface tension created by the solution itself. So, in 1 ml of water an average of 20 drops, 1 ml of fat emulsion - up to 30, in 1 ml of alcohol - up to 60 drops.

Volumetric peristaltic and syringe pumps provide high accuracy and uniformity of the introduction of pores. The pumps have a mechanical or electronic speed controller, which is measured in milliliters per hour (ml / h).

Solutions for infusion therapy

Solutions for infusion therapy include several groups: bulk-replacing (vollemic); basic, basic; corrective; preparations for parenteral nutrition.

Volume-substituting drugs are divided into: artificial plasma substitutes (40 and 60% of dextran solution, starch solutions, haemodes, etc.); natural (autogenous) plasma substitutes (native, freshly frozen - FFP or dry plasma, 5, 10 and 20% of human albumin, cryoprecipitate, protein, etc.); actually blood, erythrocyte mass or suspension of washed red blood cells.

These drugs are used to compensate the volume of circulating plasma (CDP), deficiency of erythrocytes or other components of plasma, for the purpose of sorption of toxins, to ensure the rheological function of blood, to obtain osmodiuretic effect.

The main feature of the drugs of this group: the greater their molecular weight, the longer they circulate in the vascular bed.

Hydroxyethyl starch is available in the form of 6 or 10% solution on the physiological solution (HAES-steril, infukol, stabilazol, etc.), has a high molecular weight (200-400 kD) and therefore circulates longly in the vascular bed (up to 8 days). It is used as an anti-shock drug.

Polyglucin (dextran 60) contains a 6% solution of dextran with a molecular weight of about 60,000 d. Prepared for 0.9% of sodium chloride. The half-life (T | / 2) is 24 hours, stored in circulation up to 7 days. Children rarely used. An antishock drug.

Reopoliglyukin (dextran 40) contains 10% rr of dextran with a molecular weight of 40,000 D and 0.9% of sodium chloride solution or 5% of glucose solution (indicated on the vial). T1 / 2 - 6-12 hours, the action time - up to 1 day. Note that 1 g of dry (10 ml p-ra) dextran 40 binds 20-25 ml of fluid entering the vessel from the interstitial sector. An antishock drug, the best reoprotective.

Hemodez includes a 6% solution of polyvinyl alcohol (polyvinyl pyrrolidone), 0.64% sodium chloride, 0.23% sodium bicarbonate, 0.15% potassium chloride. Molecular weight is 8000-12000 d. T1 / 2 - 2-4 h, the action time is up to 12 h. The sorbent possesses moderate detoxification and osmodiuretic properties.

In recent years, isolated the so-called dextran syndrome, caused in some patients by the special sensitivity of the epithelial cells of the lungs, kidneys and vascular endothelium to dextran. In addition, it is known that with prolonged use of artificial plasma substitutes (especially haemodesis) macrophage blockade may develop. Therefore, the use of such drugs for infusion therapy requires caution and strict indications.

Albumin (5 or 10% solution) is almost an ideal volume-substituting agent, especially with the infusion therapy for shock. In addition, it is the most powerful natural sorbent for hydrophobic toxins, transporting them to liver cells, in microsomes of which, detoxification actually occurs. Plasma, blood and their components are currently used for strict indications, mainly with a substitution purpose.

With the help of basic (basic) p-dov medicinal and nutrients are introduced. The glucose level of 5 and 10% has an osmolality of 278 and 555 mosm / L, respectively; pH 3.5-5.5. It should be remembered that the osmolarity of the p-ro is provided by sugar, the metabolism of which into glycogen with the participation of insulin leads to a rapid decrease in the osmolality of the injected liquid and, as a consequence, the threat of development of hypo-osmolality syndrome.

Solutions Ringer, Ringer-Lock, Hartman, lactasol, acesol, disol, trisol, etc. Are the closest in composition to the liquid part of human plasma and adapted to treat children, contain ions of sodium, potassium, calcium, chlorine, lactate. In the Ringer-Locke district there is also 5% glucose. Osmolarity 261-329 mosm / l; pH 6.0-7.0. Isosmolar.

Corrective solutions are used for ion imbalance, hypovolemic shock.

Physiological 0.85% of sodium chloride because of the excessive chlorine content is not physiological and almost not used in young children. Sour. Isosmolar.

Hypertensive sodium chloride (5.6% and 10%) are rarely used in pure form - with a severe sodium deficiency (<120 mmol / l) or severe intestinal paresis. A solution of 7.5% potassium chloride is used only for infusion correction of hypokalemia in the form of a supplement to glucose in the final concentration of not more than 1%. In its pure form, it can not be entered (danger of cardiac arrest!).

Sodium bicarbonate (4.2 and 8.4%) are used to correct acidosis. They are added to Ringer Ringer's physiological sodium chloride, less often to r-pu glucose.

Infusion therapy program

When drawing up a program of infusion therapy, a certain sequence of actions is necessary.

1. To establish the diagnosis of violations of the WEO, drawing attention to vollemy, the state of the cardiovascular, urinary system, central nervous system (CNS), determine the degree and characteristics of deficiency or excess water and ions.
2. Given the diagnosis, determine:
   1. purpose and objectives of infusion therapy (detoxification, rehydration, treatment of shock, maintenance of water balance, restoration of microcirculation, diuresis, administration of drugs, etc.);
   2. methods (inkjet, drip);
   3. access to the vascular bed (puncture, catheterization);
3. means of infusion therapy (dropper, syringe pump, etc.).
4. To make a perspective calculation of current pathological losses for a certain period of time (4, 6, 12, 24 hours), taking into account qualitatively quantitative assessment of the manifestation of dyspnea, hyperthermia, vomiting, diarrhea,
5. To determine the deficiency or excess of the extracellular volume of water of electrolytes, which developed during the preceding analogous period of time.
6. Calculate the physiological need of the child in water and electrolytes.
7. Summarize the volumes of physiological needs (FP), the existing deficit, the predicted losses of water and electrolytes (formerly potassium and sodium ions).
8. Determine the part of the calculated volume of water and electrolytes that can be injected into the child for a certain period of time, taking into account the aggravated circumstances (cardiac, respiratory or renal insufficiency, cerebral edema, etc.), as well as the ratio of the enteral and parenteral route of administration.
9. Correlate the estimated demand for water and electrolytes with their quantity in solutions for infusion therapy.
10. Choose the starting r-p (depends on the leading syndrome) and the baseline, which is often 10% of glucose.
11. Determine the need for the introduction of special-purpose drugs based on the established syndromic diagnosis: blood, plasma, plasma substitutes, rheoprotectors, etc.
12. Solve the question of the number of inkjet and drip infusions with the definition of the drug, the volume, duration and frequency of administration, compatibility with other agents, etc.
13. To detail the program of infusion therapy, by scheduling (on resuscitation cards) the order of appointments taking into account the time, speed and sequence of administration of the drugs.

Calculation of infusion therapy

The prospective calculation of infusion therapy and current pathological losses of water based on accurate measurements of actual losses (by weighing diapers, collection of urine and feces, vomit, etc.) for the previous 6, 12 and 24 h allows us to determine their volume for the forthcoming time interval. The calculation can be conducted and approximately by the available standards.

Deficiency or excess water in the body is easily taken into account if the dynamics of the infusion therapy is known for the past time (12-24 hours). More often deficiency (excess) of extracellular volume (DVO) is determined on the basis of clinical evaluation of the degree of dehydration (hyperhydration) and the observed deficit (excess) of MT. At the first degree of dehydration, it is 20-50 ml / kg, with II - 50-90 ml / kg, with III - 90-120 ml / kg.

To carry out infusion therapy for rehydration, only the deficit of MT, which has developed over the last 1-2 days, is taken into account.

Calculation of infusion therapy in children with normo- and hypotrophy is carried out on the actual MT. However, in children with hypertrophy (obesity), the amount of total water in the body is 15-20% less than in thin children, and the same loss of MT in them corresponds to a higher degree of dehydration.

For example: a "fat" child at the age of 7 months has MT 10 kg, for the past day he lost 500 g, which is 5% of the deficit of MT and corresponds to the I degree of dehydration. However, considering that 20% of MT is represented by additional fat, the defatted MT is 8 kg, and the deficit of MT due to dehydration is 6.2%, which corresponds to its II degree. 

It is acceptable to use the caloric method to calculate the infusion therapy of the need for water or in terms of the body surface of the child: for children under 1 year - 150 ml / 100 kcal, over 1 year - 100 ml / 100 kcal or for children under 1 year - 1500 ml per 1 m ^{2 of} the body surface, over 1 year - 2000 ml per 1 m ². The surface of the child's body can be established from nomograms, knowing the indicators of its growth and MT.

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The volume of infusion therapy

The total amount of infusion therapy for the current day is calculated by the formulas:

• to maintain the water balance: OZH = FP, where OP is the physiological need for water, the coolant is the volume of the liquid;
• with dehydration: OZH = DVO + CCI (for the first 6, 12 and 24 hours of active rehydration), where DVO - deficiency of extracellular fluid volume, CCI - current (predicted) pathological water losses; after the elimination of DVO (usually from 2 days of treatment) the formula takes the form: OZH = FP + CCI;
• for detoxification: ОЖ = ФП + ОВД, where ОВД - volume of age daily diuresis;
• with OPN and oligoanuria: OZH = FD + OP, where PD is the actual diuresis for the previous day, OP is the volume of perspiration per day;
• with OCH degree I: OZH = 2/3 FP; II degree: ОЖ = 1/3 ФП; III degree: ОЖ = 0.

General rules for compiling an algorithm for infusion therapy: 

1. Colloidal preparations contain a sodium salt and belong to saline r-frames, so their volume should be taken into account when determining the volume of saline pores. In sum, colloidal preparations should not exceed 1/3 of the coolant.
2. In young children, the ratio of glucose and salt p-glucose is 2: 1 or 1: 1, and in older age, it changes towards the predominance of saline solutions (1: 1 or 1: 2).
3. All formulas should be divided into portions, the volume of which usually does not exceed 10-15 ml / kg for glucose and 7-10 ml / kg for saline and colloidal solutions.

The choice of the initial solution is determined by the diagnosis of violations of HEI, vollemia and the tasks of the initial stage of infusion therapy. So, in case of shock, in the first 2 hours, mainly drugs of vollemic action should be administered, with hyper-sodium glucose, glucose and so on.

Some principles of infusion therapy

With infusion therapy for the purpose of dehydration, there are 4 stages:

1. anti-shock measures (1 -3 hours);
2. reimbursement of DVO (4-24 hours, with severe dehydration up to 2-3 days);
3. maintenance of VEO in conditions of continuing pathological fluid loss (2-4 days or more);
4. PP (full or partial) or enteral therapeutic diet.

Anhydrhythmic shock occurs with a rapid (hours / day) development of dehydration II-III degree. In shock, the parameters of central hemodynamics should be restored in 2-4 hours by injecting a liquid in a volume approximately equal to 3-5% of MT. In the first minutes, p-ry can be injected or quickly drip, but the average speed should not exceed 15 ml / (kg * h). When the blood circulation is decentralized, the infusion begins with the administration of sodium bicarbonate p-rots. Then, 5% of the albumin solution or plasma substitutes (reopolyglucin, hydroxyethyl starch) is introduced, then, or in parallel with it, saline solutions. In the absence of significant disorders of microcirculation, instead of albumin, a balanced saline solution can be used. Considering the presence of mandatory hypo-osmolality syndrome with anhydromic shock, the introduction of electro-electrolyte solutions (glucose solutions) into the composition of infusion therapy is possible only after restoration of satisfactory parameters of central hemodynamics!

The duration of the second stage is usually 4-24 hours (depending on the type of dehydration and adaptive capabilities of the child's body). Intravenous and (or) inside is injected with liquid (ОЖ = DVO + ТПП) at a speed of 4-6ml / (kg h). At the I degree of dehydration, it is preferable to introduce all the liquid inside.

With hypertonic dehydration, 5% of glucose and hypotonic solutions of NaCl (0.45%) in a 1: 1 ratio are administered. For other types of dehydration (isotonic, hypotonic), 10% of glucose and the physiological concentration of NaCl (0.9%) are used in balanced saline solutions in the same ratios. To restore diuresis, potassium chloride solutions are used: 2-3 mmol / (kg), and calcium and magnesium: 0.2-0.5 mmol / (kg-s). Salt solutions of the last 2 ions are better to inject intravenously drops, not mixing in one bottle.

Attention! Deficiency of potassium ions is eliminated slowly (for several days, sometimes weeks). Potassium ions are added to the glucose solutions and injected into the vein at a concentration of 40 mmol / l (4 ml of 7.5% of the KCl solution per 100 ml of glucose). It is prohibited to use a rapid, and moreover, jet, injection of potassium in the veins!

This stage ends with the addition of a child's MT, which is no more than 5-7% compared with the initial (before treatment).

The third stage lasts more than 1 day and depends on the preservation or continuation of pathological water losses (with stools, vomit masses, etc.). The formula for calculation is: OZH = FP + CCI. During this period the child's MT should stabilize and increase by no more than 20 g / day. Infusion therapy is performed uniformly throughout the day. The infusion rate usually does not exceed 3-5 ml / (kg h).

Detoxification by infusion therapy is performed only with preserved renal function and provides for:

1. dilution of toxins in the blood and EKZH;
2. an increase in the rate of glomerular filtration and diuresis;
3. improvement of blood circulation in the reticuloendothelial system (RES), including the liver.

Hemodilution (dilution) of the blood is provided by the use of colloidal and saline solutions in the regime of normo or moderate hypervolemic hemodilution (NK 0.30 l / l, bcc> 10% of the norm).

Diuresis in a child who is under conditions of postoperative, infectious, traumatic or other stress, should not be less than the age norm. When diuretics are stimulated by diuretics and liquid is injected, diuresis may increase by a factor of 2 (more rarely), and an increase in disturbances in the ionogram is possible. The child's MT should not change at the same time (which is especially important in children with CNS lesions, the Dicatric system). The infusion rate is an average of 10ml / kg * h), but it can be longer with the introduction of small volumes in a short time.

If there is insufficient detoxification with the help of infusion therapy, you should not increase the volume of fluid and diuretics, and include in the treatment complex methods of efferent detoxification, extracorporeal cleansing of the blood.

Treatment of hyperhydration is carried out taking into account its degrees: I - increase of MT to 5%, II - within 5-10% and III - more than 10%. The following methods are used:

• limitation (not abolition) of water and salt administration;
• recovery of bcc (albumin, plasma substitutes);
• the use of diuretics (mannitol, lasix);
• hemodialysis, hemodiafiltration, ultrafiltration or low-flow ultrafiltration, peritoneal dialysis in acute renal failure.

In hypotonic hyperhydration, it may be useful to pre-administer small volumes of concentrated solutions (20-40%) of glucose, sodium chloride or bicarbonate, and albumin (in the presence of hypoproteinemia). It is better to use osmotic diuretics. In the presence of OPN, emergency dialysis is shown.

Hypertonic hyperhydration is effective diuretic drugs (lasix) against a background of careful intravenous injection of 5% glucose.

When isotonic hyperhydration prescribed restriction of fluid and table salt, stimulate diuresis with lasix.

During the infusion therapy it is necessary:

1. Continuously evaluate its effectiveness by changing the state of central hemodynamics (pulse) and microcirculation (skin color, nails, lips), kidney function (diuresis), respiratory system (BH) and CNS (consciousness, behavior), as well as changes in clinical signs of dehydration or hyperhydration .
2. Instrumental and laboratory monitoring of a patient's functional state is mandatory:

• hourly measure heart rate, BH, diuresis, lost volumes with vomiting, diarrhea, dyspnea, etc., according to indications - blood pressure;
• 3-4 times (sometimes more often) within a day register the body temperature, blood pressure, CVP;
• before the start of the infusion therapy, after its initial stage and then daily determine the parameters of NaCl, total protein, urea, calcium, glucose, osmolality, ionogram, parameters of CBS and WEO, prothrombin level, coagulation time (VSC), relative density of urine ).

3. The volume of the infusion and its algorithm are subject to mandatory correction depending on the results of infusion therapy. If the patient's condition worsens, the infusion therapy stops.
4. When correcting significant FEV shifts, the sodium level in the blood plasma of the child should not increase or decrease faster than by 1 mmol / Lh) (20 mmol / L per day), and the osmolarity index by 1 mOsm / Lh) (20 mOsm / L in day).
5. In the treatment of dehydration or hyperhydration, the weight of the child's body should not vary over a day by more than 5% of the original.

In the drip tray, more than% of the coolant calculated per day should not be placed at the same time.

In the course of infusion therapy, mistakes may be made: tactical (incorrect calculation of OLC, OI and determination of the components of IT, incorrectly formulated infusion therapy program, errors in determining the IT rate, in measuring the parameters of blood pressure, CVP, etc., defective analyzes, unsystematic and incorrect control of the conduct of IT or its absence) or technical (wrong choice of access, the use of substandard drugs, defects in care of systems for transfusion of solutions, improper mixing of solutions).

Complications of infusion therapy

1. local hematomas and necrosis of tissues, damage to adjacent organs and tissues (with puncture, catheterization), phlebitis and vein thrombosis (due to high osmolarity of the pits, their low temperature, low pH), embolism;
2. water intoxication, salt fever, edema, acidosis of dilution, hypo and hyperosmolar syndrome;
3. reactions to infusion therapy: hyperthermia, anaphylactic shock, chills, circulatory disorders;
4. overdose of drugs (potassium, calcium, etc.);
5. complications associated with blood transfusion, transfusion reactions (30 min - 2 h), hemolytic reactions (10-15 min and more), a syndrome of massive blood transfusions (more than 50% bcc per day);
6. overload of the circulatory system due to excess of injected solutions, high rate of their administration (swelling of the cervical veins, bradycardia, widening of the heart, cyanosis, possible cardiac arrest, pulmonary edema);
7. pulmonary edema due to a decrease in colloid osmotic pressure in the plasma and an increase in hydrostatic pressure in the capillary (haemodulation with water over 15% BCC).

The introduction of a procedure such as infusion therapy into the wide medical practice allowed to significantly reduce the death rate of children, but at the same time gave rise to a number of problems that are more often associated with inaccurate diagnosis of WEO violations and, accordingly, incorrect determination of indications, volume calculation and compilation of the IT algorithm. Proper IT implementation can significantly reduce the number of such errors.

[3], [4], [5], [6], [7], [8], [9], [10]