Angiogenic infection

Angiogenic infection is the primary infection of the bloodstream, the source of which is in the blood vessels or in the heart cavities. The laboratory indicator of angiogenic infection is considered bacteremia, and clinical symptomatic complex of sepsis. Angiogenic infection includes infectious endocarditis, septic thrombophlebitis and sepsis due to infection of vascular prostheses, stents, shunts and other intravascular devices. In the practice of intensive care units, the overwhelming number of cases of angiogenic infection is associated with the use of vascular arterial catheters, peripheral venous and, primarily, pulp and paper mills. Therefore, the further description will relate specifically to catheter-associated blood flow infections (CAIC)

[1], [2], [3], [4], [5], [6], [7]

Epidemiology

Domestic data on the incidence of angiogenic infection, including CAIC, does not exist in intensive care units. According to the US Centers for Disease Control and Prevention, the average level of CAICs associated with the pulp and paper industry in the ICU is 5.3 per 1000 catheter-related (the sum of catheter days). Annually in the United States, the catheter-borne amount of all ICU patients is 15 million, approximately 80,000 cases of CAIC are associated with the pulp and paper mill each year. The level of mortality due to cases of intravascular systemic infection remains uncertain.

If we estimate the number of cases of CAIC not only in the ICU, but in all hospitals, 250,000 such episodes are recorded annually. In these cases, the lethality from this complication is estimated at 12-25%, the minimum healthcare costs are $ 25,000 for each case.

Most cases of intravascular systemic infection are associated with the use of pulp and paper mills. Among patients with pulmonary embolism, the proportion of bloodstream infections is significantly higher than in patients without catheters. The frequency of CAICs associated with the pulp and paper industry varies depending on the size and profile of the departments and ranges from 2.9 (in cardiosurgical ICUs) to 11.3 (in the departments for premature infants) of cases per 1000 cathetered.

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

What causes angiogenic infection?

The most frequent causative agents of CAIC in the ICU are coagulase-negative staphylococci and Staphylococcus aureus. They constitute 27% and 13-16% of all cases of the CAIC, respectively. More than 50% of Staphylococcus aureus isolates from patients with ICU are characterized by resistance to oxacillin. In recent years, the share of enterococci has increased (from 8% to 12.5%) and strains resistant to vancomycin have appeared. Fungi of the genus Candida cause 8% of cases of nosocomial bloodstream infections. At the same time, the proportion of Candida strains that are resistant to widely used antifungal agents is growing. Up to 10% of isolates of C. Albicans, obtained from the blood of hospitalized patients, are resistant to fluconazole. In 48% of cases of candidal infection of the blood stream, the pathogens are C. Glabrata and C. Krusei, which are even more resistant to fluconazole and itraconazole than C. Albicans.

The number of CAIC cases caused by gram-negative bacteria is 14-19% of the total number of CAICs. At the same time, among the Gram-negative pathogens, the percentage of isolates obtained from the ICU patients increased. This increase was due to the bacteria of the genus Enterobactenaceae, producing beta-lactamase extended spectrum, in particular due to Klebsiella pneumoniae. Such microorganisms are resistant not only to cephalosporins of the extended spectrum of action, but also to broad-spectrum antibiotics.

Pathogenesis

Infection of the catheter can occur in three ways. The first is the migration of microorganisms from the skin through the exit site of the catheter along its outer surface towards the distal segment. This mechanism is most relevant in the first 10 days after placement of the catheter. In later periods, the priority is the ingress of microorganisms into the bloodstream through the lumen of the catheter, while the main sources of infection are the contaminated catheter cannulas, infusion systems and solutions. The third way is endogenous, when microorganisms entering the bloodstream from other sources settle on the intravascular segment of the catheter. In this situation, the catheter can become a secondary source of bacteremia.

Pathogenesis of CAIC is based on complex interactions of several factors. The catheter behaves like a foreign body, in response to the introduction of which the host's organism produces a fibrin film covering the surface of the intravascular segment of the catheter. This film is rich in fibrin and fibronectin, to which the affinity of Staphylococcus aureus and Candida spp. Both species produce coagulase, gaining an advantage in the thrombogenic process occurring on the surface of the catheter, and tightly adhering to the film. Coagulase-negative staphylococci can be attached to fibronectin. They produce an adhesive substance, glycocalyx, which facilitates attachment and protects against the effects of complement, phagocytes and antibiotics. This fact can explain why it is coagulase-negative staphylococcus that dominates the CAIC. Other microorganisms, such as Pseudomonas aeruginosa and Candida spp., Can synthesize similar substances, especially when they grow on a medium rich in glucose. Attached microorganisms, reproducing, form microcolonies, secrete an extracellular polysaccharide matrix, which forms the architectural structure of the biofilm. An increase in the weight of the biofilm and its fragmentation lead to the entry of microorganisms into the bloodstream (planktonic forms), which is clinically manifested by bacteremia and the symptomatic complex of sepsis.

Classification of angiogenic infections

Currently, the world practice uses the classification of catheter-associated infections, developed by the Advisory Committee for the Practical Control of Hospital Infections in the United States.

• Colonization of the catheter is> 15 cfu in semiquantitative microbiological examination or> 102 cfu with a quantitative method for the distal segment of the remote catheter in the absence of concomitant clinical symptoms.
• Infection of the exit site of the erythema catheter, tenderness, infiltration, suppuration within 2 cm around the outer site of the catheter, the release of pus and the appearance of fever are often combined with bacteremia.
• Pocket infection of erythema and necrosis of the skin above the reservoir of the implanted port or purulent exudate in the subcutaneous pocket containing the port may be accompanied by bacteremia.
• Tunnel infection of erythema, tenderness and infiltration of tissues surrounding the catheter, extending beyond 2 cm from the exit site of the catheter, spreading along the subcutaneous tunnel can be accompanied by bacteremia.
• CACI release of the same microorganism (i.e., the same species and antibioticogram) in a semi-quantitative or quantitative method for examining a segment of a remote catheter and peripheral blood in a patient with concomitant symptoms of a bloodstream infection and in the absence of another source of infection, The decrease in temperature after removal of the catheter can be an indirect proof of the CAIC.
• Infection of blood flow associated with infuzatom (a rare variant of infection that occurs when intravenously introduced through the catheter of contaminated infusion solutions or blood components is determined by the release of the same microorganism from the infusate and in the blood culture from the peripheral vein in the absence of another source of infection).

The complications of CACIC include infective endocarditis, osteomyelitis, septic arthritis, metastatic purulent screenings of other localization.

Given the different periods of catheter use, the assessment and comparison of the frequency of different variants of catheter-associated infection are conducted not only by the number of cases per 100 functioning pulp and paper mills (in%), but also by the number of cases per 1000 catheters (the sum of catheter days).

[11], [12], [13], [14], [15], [16], [17], [18]

Diagnosis of angiogenic infections

Diagnosis of CAIC is established on the basis of clinical and microbiological tests.

The clinical symptoms of a catheter-associated infection are divided into local and general. To the local include soreness, flushing, infiltration, skin necrosis, pus in the exit zone of the catheter, subcutaneous tunnel or implanted "port", as well as pain and tightness along the veins (phlebitis). The general manifestations of CAIC are characterized by a symptom-complex of sepsis, they are classified by severity. The clinical picture of CAIC depends on the degree of colonization of the catheter and the nature of the microflora, and varies from subfebrile fever and light fever after administration of solutions through the catheter (with colonization by coagulase-negative staphylococci, Micrococcus spp, Corynebacterium, Bacillus subtilis) to severe sepsis and septic shock (colonization of Staphylococcus aureus and gram-negative bacteria). Fungal CAIK is characterized by a protracted course with high fever. Local infection, especially purulent, is often combined with CAIC, but its absence does not exclude infection of the distal intravascular region of the catheter.

For the diagnosis of CAIC, only clinical data are insufficient due to the low specificity of the most sensitive symptoms (such as fever, chills) or low sensitivity of specific symptoms (eg, inflammation or suppuration in the catheter area). Therefore, the appearance of a systemic infection in a patient with a vascular catheter for 72 hours or more and the absence of other foci of infection should be regarded as a probable CAIC. Isolation from hemocultures obtained with puncture of the peripheral vein, coagulase-negative staphylococci, Staphylococcus aureus or Candida spp. Increases the likelihood of a CAIC diagnosis. For further more accurate diagnosis it is necessary to perform quantitative microbiological studies.

When the catheter is removed, semiquantitative or quantitative microbiological examination of the distal (intravascular) segment of the catheter is performed. In aseptic conditions, after treatment of the skin in the catheter area with a solution of an antiseptic and 70% ethanol solution, the catheter is removed, the distal end 5-6 cm long is cut with sterile scissors and placed in a sterile Petri dish. In semi-quantitative analysis, the segment of the catheter is rolled over the surface of the blood agar. Growth> 15 cfu indicates colonization of the catheter and a high probability of CAIC. Growth <15 cfu should be regarded as a catheter contamination with a low probability that it served as a source of systemic infection (the sensitivity of the method is about 60%). This method allows to reveal the external colonization of the catheter and is more informative with the duration of catheterization to two weeks, when the external pathway of infection is more likely. In the case of quantitative analysis, the segment of the remote catheter is treated in various ways (by jetting the lumen, agitating or ultrasonic), allowing microorganisms to be washed into the liquid medium, not only from the outer surface, but also from the lumen of the catheter. After dilution, the resulting wash is plated on blood agar and incubated. Diagnostically significant growth is> 102 CFU.

In combination with the simultaneous sowing of blood from the peripheral vein, the results of bacteriological examination are interpreted as follows. With clinical symptoms of systemic infection, isolation from microculture obtained from peripheral venous puncture, microorganisms and colonization of the catheter (> 15 cfu for semiquantitative and> 102 cfu with a quantitative method), the latter is considered a source of bacteremia. When isolating microorganisms from the hemoculture obtained from puncture of the peripheral vein, and the catheter contamination (<15 CFU in semiquantitative or <102 CFU in the quantitative method of inoculation), the latter is most likely contaminated from the blood stream and does not serve as a source of bacteremia. In the absence of growth in the blood culture and the proven colonization of the catheter (> 15 cfu for semiquantitative and> 102 cfu with a quantitative method), the bacteremia from which the catheter serves is intermittent.

For those cases where removal of the catheter or changing it through a conductor is impossible or undesirable, quantitative methods are proposed that do not require removal of the catheter. Simultaneously, equal volumes of blood are taken from the catheter and peripheral vein, then plated on molten blood agar and incubated for 24-48 hours, after which the number of colonies is counted. With fivefold or more exceeding the number of colonies in the crop from the catheter over the number of colonies sown from the peripheral vein, the CAIC is considered proven. Modern automatic diagnostic systems make it possible to perform a similar quantitative test comparing the time of a positive response in blood cultures simultaneously obtained from a pulmonary embolization and peripheral vein. The appearance of the growth of the same microorganism in a sample from the pulp-and-paper plant earlier than in peripheral blood with a difference of more than 120 min indicates a CACIC (91% sensitivity, 94% specificity).

If there is a suspicion of an infection associated with finding a catheter in the pulmonary artery, a bacteriological study of the intravascular segment of the introducer should be performed, as it is much more likely to become infected than the segment of the catheter located in the pulmonary artery.

The infected peripheral venous catheter is removed with the obligatory subsequent semi-quantitative microbiological examination. At the same time, blood must be sown from the intact periphyric vein before treatment with antibiotics.

With local infection, it is necessary to sow the exudate from the place of exit of the catheter for examination of the smear on Gram and sowing on nutrient media.

A hemoculture study from the catheter or sowing of the segment of the remote catheter should be performed only if there is a suspicion of a CAIC. In this case, it is advisable to perform quantitative or semi-quantitative studies, while quality crops are not recommended in connection with their low information content. To identify bacteremia, two cultures of blood should be examined, one from the pulp-and-paper plant, the other from the peripheral vein. If the culture is isolated from blood taken only from the catheter, it is difficult to establish whether the catheter is colonized, colonized by a catheter or bacteremia. However, the negative result of blood from the catheter with a high probability indicates that there is no infection associated with the established catheter. If seeding from a segment of a remote catheter or haemoculture collected from a catheter is negative, it is necessary to continue searching for another source of infection.

In ICU patients with other foci of infection (pneumonia, peritonitis, purulent wounds), CAIC has its own characteristics. Systemic antibiotic treatment prevents the development of CAIC or postpones its development, but promotes the selection of resistant strains of bacteria (Staphylococcus aureus, Klebsiella spp, Pseudomonas aeruginosa) and increases the likelihood of fungal infection. Background infection masks the clinical manifestations of CAIC, therefore it is necessary to have a certain caution in relation to the possibility of developing CAIC and at the slightest suspicion of performing a microbiological study. With each new episode of fever, leukocytosis and other signs of systemic inflammation, in addition to assessing the condition of the main foci of infection, it is necessary to repeat quantitative microbiological studies of blood from the catheter and peripheral vein.

Preservation of fever and bacteremia after removal of the catheter and initiation of antibiotic therapy indicates a high probability of complications. The combination of symptoms of systemic inflammation and signs of venous insufficiency or pain along the course of the catheterized vein indicates the development of septic thrombophlebitis, which can be confirmed by ultrasound (duplex scanning), phlebography or computed tomography with contrasting vessels. When isolating S. Aureus or Candida spp. In blood cultures. It is necessary to perform transesophageal or transthoracic echocardiography to assess the state of the mitral valve flaps, to identify vegetation typical for septic endocarditis. Metastatic suppurative screenings of other localization (osteomyelitis, septic arthritis) are diagnosed on the basis of local clinical symptoms and confirmed by X-ray methods.

[19], [20], [21], [22], [23], [24], [25], [26]

Treatment of angiogenic infections

When choosing the means of treatment of the CACIC, it is necessary to take into account a number of circumstances the severity of the clinical manifestations of infection (subfebrile fever, febrile fever, severe sepsis, septic shock), the nature of the pathogen, the presence of local inflammation at the site of the catheter (infiltration, pus, pain), the need for pulp and paper possibility of alternative venous access, type of pulp and paper mill (removable non-tunnel, tunnel, implanted "port").

The CACIC treatment includes a number of activities:

Catheter removal

It is necessary to carefully examine the place of catheterization. If there is pus from the insertion site or other signs of inflammation, the catheter should be removed. In patients with septic shock, in the absence of another source of infection, the catheter should be removed and the new catheter installed elsewhere. Tunnel pulp and paper or an implanted "port" is removed in the event of a tunnel or pocket infection. In the absence of signs of local inflammation and uncomplicated CAIC, an attempt may be made to sanitize the tunneling pulp and paper mill or an implanted "port" without removal. If the nature of the isolated microorganism (resistant strains of bacteria or fungi) and the severity of the patient's condition (septic shock, PON) do not allow the catheter to be sanitized and cope with the infection, the catheter must be removed.

[27], [28], [29], [30], [31], [32]

Prescribing antibiotics

In case of severe infection (severe sepsis, septic shock) or immunosuppression (neutropenia, glucocorticoids, uremia, diabetes mellitus), it is necessary to empirically prescribe antibiotic therapy, which is corrected after receiving the data of microbiological analyzes. For the empirical treatment, drugs effective for Staphylococcus epidermidis or S. Aureus are usually used. Antibiotics that are active against gram-negative microorganisms should be prescribed to patients with immunosuppression, neutropenia, or other risk factors for developing a gram-negative infection. With an average or mild infection, treatment with antibiotics should be prescribed, but with the disappearance of symptoms of infection after removal of pulmonary embolism, antibiotic therapy is not necessary.

The choice of the drug and the way of administration of the antibiotic is determined by the properties of the isolated microorganism, the severity of the clinical manifestations of infection, the design of the pulp and paper mill. Three ways of administering antibiotics are used:

• systemic therapy by intravenous administration is used at the first stage and with a severe clinical course of infection,
• reception of antibiotics inside is expedient at stabilization of a condition of the patient and necessity of continuation of systemic treatment by antibiotics,
• "Antibacterial lock" (by analogy with the heparin "lock") the introduction of small volumes of solutions of antibiotics in high concentrations into the lumen of the pulp-and-paper plant with subsequent exposure for several hours (for example, 8-12 hours at night when the pulp and paper mill is not used).

The latter method is used alone or in combination with systemic antibiotic therapy in cases of intraluminal infection of the pulp and paper industry, the removal of which is not entirely desirable (for example, a tunneling pulp and paper mill or an implanted "port"). As a "lock" can be used vancomycin in a concentration of 1-5 mg / ml, gentamicin or amikacin at a concentration of 1-2 mg / ml, ciprofloxacin at a concentration of 1-2 mg / ml. Antibiotics are dissolved in 2-5 ml of isotonic sodium chloride solution with addition of 50-100 ED of heparin. Before the subsequent use of the catheter, the antibiotic "lock" is removed.

If coagulase-negative staphylococci are detected, if the isolated strain is sensitive to methicillin, administer oxazillin intravenously at a dose of 2 g at intervals of 4 hours. Alternative preparations are cephalosporins of the first generation (cefazolin 2 g every 8 h), vancomycin at a dose of 1 g at intervals of 12 h or co-trimoxazole, 3-5 mg / kg every 8 hours. Vancomycin has advantages over oxacillin and cephalosporins of the first generation, but the latter is more preferable because of the increase in resistance to vancomycin. When methicillin-resistant strains of coagulase-negative staphylococci are detected, the drug of choice is vancomycin in a dose of 1 g every 12 h intravenously. The second-line drug is linezolid (zivox) at a dose of 600 mg every 12 hours intravenously (for adults weighing <40 kg, the dose of linezolid is 10 mg / kg). Duration of treatment - 7 days. If the catheter is not removed, systemic therapy is supplemented by performing an "antibiotic lock" for up to 10-14 days.

When a susceptible susceptible to methicillin S aureus is prescribed intravenously, oxacillin in a dose of 2 g with an interval of 4 hours. Alternative drugs are cephalosporins of the first generation (cefazolin 2 g every 8 hours). In the isolation of methicillin-resistant strains of S. Aureus, the drug of choice is vancomycin at a dose of 1 g intravenously every 12 hours. There may be a decrease in the sensitivity of S. Aureus to vancomycin. In this case, the appointments are supplemented with gentamicin or rifampicin. The second-line preparation is linezolid, administered 600 mg every 12 hours intravenously or co-trimoxazole at a dose of 3-5 mg / kg every 8 hours (with sensitivity). When isolating strains of S. Aureus resistant to vancomycin, the drug of choice is linezolid administered at a dose of 600 mg at an interval of 12 hours intravenously (for adults weighing <40 kg, the dose of linezolid is 10 mg / kg). Duration of treatment is 14 days. If the tunneling pulp and paper mill or port is not removed, an "antibiotic lock" is performed. With endocarditis, persistent or repeated bacteremia, pulmonary embolism is removed, systemic antibiotic treatment lasts up to 4-6 weeks.

For the treatment of enterococcus CACIC (E. Faecalis or E. Faecium), with sensitivity to ampicillin, ampicillin is given at a dose of 2 g every 4 to 6 hours in the form of monotherapy or in combination with gentamycin at a dose of 1 mg / kg every 8 hours. Vancomycin in this situation is not prescribed because of the possible development of resistance. With the resistance of enterococci to ampicillin, treatment is performed with vancomycin in the form of monotherapy or in combination with gentamicin. The second-line preparation is linezolid. When identifying resistance to vancomycin, the drug of choice is linezolid. Duration of treatment is 14 days. To preserve the pulp and paper mill, an "antibiotic lock" is performed for up to 14 days.

To treat infections caused by gram-negative bacteria, antibiotics are prescribed according to the sensitivity of the isolated microorganism. When detecting E coli or Klebsiella spp, cephalosporins of the third generation (ceftriaxone 1-2 g per day) are prescribed. Alternative preparations fluoroquinolones (ciprofloxacin, levofloxacin) or aztreonam. In case of CACIC caused by Enterobacter spp or S marcescens, the first line drugs are carbopenems (imipenem + cilastatin 500 mg every 6 hours or meropenem 1 g every 8 hours), second line drugs - fluoroquinolones (ciprofloxacin, levofloxacin). To treat an infection caused by Acinetobacter spp., Ampicillin + sulbactam is prescribed at a dose of 3 g every 6 hours or carbapenems (imipenem + cilastatin 500 mg every 6 hours or meropenem 1 g every 8 hours). When S Maltophilia is detected, co-trimoxazole is administered at a dose of 3-5 mg / kg every 8 hours, an alternative drug is ticarcillin + clavulonic acid. To treat infection caused by P. Aeruginosa, use cephalosporins III (ceftazidime 2 g every 8 h) or IV (cefepime 2 g every 12 h) generation, carbapenems (imipenem + cilastatin 500 mg every 6 h or meropenem 1 g every 8 hours), anti-synergistic ß-lactam antibiotics (ticarcillin + clavulonic acid 3 g every 4 h) in combination with aminoglycosides (amikacin 15 mg / kg after 24 h) Treatment lasts 10-14 days. To preserve the pulp and paper mill, an "antibiotic lock" is performed for up to 14 days. In the absence of efficacy, pulmonary embolism is removed, and systemic administration of antibiotics is continued for 10-14 days.

It should be remembered that the recommended regimens of antibiotic therapy, which showed high efficacy on a large statistical material for a certain type of microorganism, may not be effective for a particular isolated strain, since the sensitivity of gram-negative bacteria to antibiotics can vary widely.

In the treatment of CAIK caused by a fungal microflora (With albicans or Candida spp), the leading role belongs to amphotericin B (intravenously at a dose of 0.3-1 mg / kg daily). Fluconazole in a dose of 400-600 mg every 24 hours should be prescribed only in cases of proven sensitivity to it of an isolated strain of fungi. In the case of fungal infection, the pulp and paper industry of any design must necessarily be removed due to ineffective sanitation. Treatment with antifungal drugs should continue for 14 days after the last positive result of culture of the culture.

Treatment of CAIC caused by rare microorganisms must be carried out taking into account their sensitivity to antibiotics. In the isolation of Corynebactenum spp or Flavobacterium spp, vancomycin should be given, with the isolation of B. Cepacia-co-trimoxazole or carbapenems, O. Anthropi-co-trimoxazole or fluoroquinolones, T. Beigelii-ketoconazole, M. Futfur-amphotericin B In all cases, remove. When M. Futfur is detected, intravenous administration of fatty emulsions should be stopped.

With organ dysfunction (renal or hepatic insufficiency), appropriate correction of antibiotic doses is necessary.

Complicated CAIC requires prolonged antibiotic treatment with endocarditis - up to 4-6 weeks, with osteomyelitis - up to 6-8 weeks. If treatment with antibiotics is ineffective, surgical intervention is indicated.

Treatment of complications

Pathogenetic association of coagulation and infectious processes often leads to thrombosis of the catheterized central vein. In this case, anticoagulant therapy with heparin sodium should be prescribed.

Surgery

Treatment of septic thrombophlebitis includes mandatory removal of the catheter, opening and draining or excising of the infected peripheral vein Surgical sanation is indicated with subcutaneous phlegmon, purulent arthritis, osteomyelitis and septic excreta of other localization.

Prevention of angiogenic infections

Prevention of catheter-associated infections is of great importance because of its high efficiency. The system of preventive measures is based on identifying risk factors and reducing their impact through the use of various prevention methods.

The risk factors for the development of angiogenic infection can be divided into three main groups.

• factors associated with the patient
  • o-extreme age groups (children 1 year and younger, adults 60 years and older),
  • granulocytopenia (<1.5 × ^{10 9} / L with increasing risk at <0.5 × ^{10 9} / L),
  • immunosuppression associated with disease or treatment,
  • skin lesions (psoriasis, burns),
  • severity of the condition,
  • The presence of infectious diseases or complications,
• factors associated with vascular catheters
  • material and design of the catheter,
  • variant of vascular access,
  • duration of catheterization (> 72 h),
• factors associated with the installation and use of catheters
  • aseptic maintenance during the installation and use of the catheter,
  • variety of manipulations

The first group of factors is practically not amenable to correction, therefore, the recommendations on the prevention of CAIC are related to the factors of the second and third groups.

The leading role in prevention is played by professional training of personnel and strict implementation of the rules of antiseptics and asepsis when installing and working with vascular catheters. To this end, in each hospital, instructions should be developed to standardize the work of personnel and provide a material basis for work. It is necessary to conduct classes with personnel and control knowledge and skills on the prevention of nosocomial infections in the ICU. Creation of specialized groups dealing only with intravenous assignments allows to reduce the frequency of CAIC in 5-8 times. Implementation of the asepsis requirements, similar to those for surgical interventions (the treatment of the patient's skin in the puncture area, the lining of the operating field, the treatment of the doctor's hands, the use of sterile gloves, a gown, a mask and a cap) during the installation of a pulmonary embolism reduces the risk of infection 4-6 times. To treat the patient's skin prior to catheterization and during the care of the catheter, a 10% solution of iodopyrone, 70% ethanol solution, 2% aqueous or alcoholic chlorhexidine solution should be used. The latter, perhaps, is most effective for prevention of CAIC.

Catheterization of the subclavian vein is associated with a lower frequency of CAIC than the catheterization of the internal jugular or femoral veins, which is associated with a smaller number of microorganisms on the surface of the skin in the area of installation of the pulp-and-paper plant. Catheters made of polyurethane or Teflon are less likely to be infected than polyethylene or polyvinylchloride. Using catheters with an antimicrobial coating of silver sulfadiazine and chlorhexidine reduces the risk of CAIC for 14 days after catheterization in a group of patients at increased risk of developing a CAIC. Tunnel catheters with dacron or silver clutch, which prevents infection of the outer surface of the catheter, can reduce the frequency of CAIC in the first 10-14 days.

Systemic or local ("antibiotic lock" or daily treatment of the catheter outlet area) preventive use of antibiotics or antiseptics reduces the frequency and prolongs the development of CAIC, but increases the risk of antibiotic-resistant bacteria and colonization of catheters by fungal flora.

There were no differences in the frequency of the CAIC when using single-lane or multi-lane (two- or three-lane) pulp and paper mills. However, for catheterization, a catheter with a minimum number of lumens should be used to ensure the treatment program.

It is necessary to strictly comply with the timing of replacement of infusion systems, connectors, stopcocks and other parts connected with catheters. Typically, the system is replaced after 72 hours. When infusion of fat emulsions, the replacement period should be shortened to 12-24 hours. For transfusions of blood components, the system must be replaced every 12 hours.

Planned replacement of the DCC by the conductor or with the change of access does not reduce the risk of CAIC.

An effective measure of CACIC prophylaxis is regular examination and assessment of the catheter condition, timely treatment of the skin and replacement of the dressing in accordance with the instructions of the medical institution and with the contamination.

The current and stage analysis of infectious complications associated with CEC is extremely important. It allows you to identify sources of infection and the nature of nosocomial microflora in a particular compartment, identify and eliminate errors in the work of personnel, improve prevention measures.