**4. Factors of nosocomial infections**

Factors that affect the complex process of origin and spread of nosocomial infections are divided into internal and external:


**27**

transfusion [19].

**5. Prevention**

*Pseudomonas aeruginosa* as a Cause of Nosocomial Infections

Hospital placement: plays an important role, with the highest incidence being typical of ICU. The incidence of nosocomial infection also depends on the type of ICU, while the different incidence will be on surgical, traumatological, burn, neurological, neurosurgical or cardiological ICU. Pediatric ICU is unique in that it

The patient's age may affect the risk of nosocomial infection. In the pediatric population, young children are most at risk, especially newborns. The highest incidence of nosocomial infections among pediatric patients is in children less than 1 year of age. The relative immaturity of the newborn's immune system, associated with routine ICU procedures that bypass the physical barriers of infection such as skin and mucous membranes, is responsible for the increased risk. Parenteral nutrition with high concentrations of glucose and lipids is another risk factor for infection. The fact that premature infants are most affected by these risk factors explains why neonatal ICUs have a higher incidence of nosocomial infections than pediatric ICUs [2, 4, 16]. Pediatric ICU is also unique in that each childhood has a different incidence depending on the type of nosocomial infection. In children under 5 years of age, the 3 most common nosocomial infections are in the following order: bloodstream infections, so-called bloodstream infections, pneumonia and urinary tract infections. In children aged 5 to 12 years, the 3 most common are nosocomial infections: pneumonia, bloodstream infections and urinary tract infections. In adolescents, the order of the most common nosocomial infections is: bloodstream infections, urinary tract infections, and then pneumonia [2, 4, 16]. Immunosuppressed patients after chemotherapy, human immunodeficiency virus infection, or steroid use are equally at risk for developing nosocomial infection.

provides care in all of these areas for all children except newborns [2].

Nosocomial infections do not have an apparent sex predilection.

mial infections, due to increased staff workload and poor hand hygiene [18]. Erythrocyte transfusion is a risk factor for the development of nosocomial infections in critically ill patients on ICU. In a prospective study, the incidence of nosocomial infection was 14.3% in patients with blood transfusions and 5.8% in patients without blood transfusions. In the group of patients with blood transfusions, there was a higher incidence of nosocomial infections, which was significant in seriously ill patients with a probability of survival of less than 25%. Patients with more than a 25% chance of survival had higher mortality, longer stays on the ICU, and longer hospitalizations compared with patients who did not receive a blood

hospital stay and initial antibiotic therapy [17].

Particular risk factors for the development of nosocomial infection are length of

Staff shortages are a particular risk factor for the increased incidence of nosoco-

It is not possible to eliminate all nosocomial infections, but one third of cases could be prevented if organized infection control programs were put in place.

Preventive measures can be divided into 2 categories, namely standard measures and transmission-based measures. Standard measures can always be used and are designed to prevent personnel from coming into contact with potentially infectious body fluids. The most important standard measure is hand hygiene. Washing hands with soap and water is considered the gold standard. The use of anhydrous antiseptic agents is accepted, but not in cases where visible dirt is present, proteinaceous body fluids such as blood, or spores contamination is suspected. In these cases, it is necessary to use soap and water. Hand hygiene must be observed before and after

*DOI: http://dx.doi.org/10.5772/intechopen.95908*

#### *Pseudomonas aeruginosa* as a Cause of Nosocomial Infections *DOI: http://dx.doi.org/10.5772/intechopen.95908*

*Pseudomonas aeruginosa* - Biofilm Formation, Infections and Treatments

contributes to reducing the incidence of VAP [2].

resistance in the healthcare setting [10].

**4. Factors of nosocomial infections**

tions are divided into internal and external:

**3. Treatment**

infections.

Daily consideration is recommended as to whether the patient can be extubated. Discontinuation of sedation is impractical for most children in pediatric ICUs, as it can potentially lead to unwanted extubation, especially in children who are small enough to cooperate or understand the need for intensive care interventions. Studies in adults and children show that the use of non-invasive ventilation in ICU

One of the most important challenges for physicians is the adequate treatment of infections due to Gram-negative pathogens because of the increasing antimicrobial

Among infections caused by Gram-negative rods, *P. aeruginosa* has a leading role [11], especially in critically ill and immunocompromised patients. Antimicrobial resistance has led to a serious restriction in treatment options for *P. aeruginosa*

An anti-pseudomonal cephalosporin, or a carbapenem, or an anti-pseudomonal β-lactam/BLI represents potential options for definitive therapy. Aminoglycosides should not be used as monotherapy because success rates for aminoglycosides are low [8]. This may be due to the poor penetration of aminoglycosides into the lung, which require high peak serum concentrations to obtain adequate lung concentrations, thus increasing the risk of nephrotoxicity or ototoxicity [12, 13]. However, because in Europe fluoroquinolone resistance rate in P. aeuruginosa exceeds 30% [14], it is appropriate to use combination therapy including aminoglycosides for empirical therapy of serious VAP. A based approach is recommended of the prescription of an anti-pseudomonal β-lactam (piperacillin/tazobactam, ceftolozane/ tazobactam, ceftazidime, cefepime, or a carbapenem) plus a second anti-pseudomonal agent (aminoglycoside or a fluoroquinolones). As for aerosol therapy, there is not routinely recommended the use of inhaled antibiotics for the treatment of *P. aeruginosa* VAP. However, they may be considered as an adjunctive to intravenous therapy in cases of infections due to MDR (Multi-drug resistance) strains [15].

Factors that affect the complex process of origin and spread of nosocomial infec-

• internal factors are closely related to the biological balance of the patient: age (over 60 years, up to 3 years), alcoholism, drug addiction, hormonal disorders (diabetes), malignant tumors, immunodeficiency, obesity, malnutrition, circulatory disorders, polytraumas, burns, pressure ulcers, ulcus cruris, other

• external factors are related to therapeutic, prophylactic and diagnostic interventions and are used exclusively in treatment of patients in hospital facilities: length of hospital stay, surgery, transplantation, tracheostomy, endotracheal cannula, gastric tube, urinary catheterization, iv catheterization, infusion, transfusion, foreign bodies, drainage, instrumental procedure, repeated anesthesia, endoscopy, hemodialysis, radiation therapy, cytostatic therapy, immunosuppressive therapy, broad spectrum ATB therapy, hormonal therapy [3].

serious diseases (liver disease, AV shunt, cardiomyopathy),

**26**

Hospital placement: plays an important role, with the highest incidence being typical of ICU. The incidence of nosocomial infection also depends on the type of ICU, while the different incidence will be on surgical, traumatological, burn, neurological, neurosurgical or cardiological ICU. Pediatric ICU is unique in that it provides care in all of these areas for all children except newborns [2].

The patient's age may affect the risk of nosocomial infection. In the pediatric population, young children are most at risk, especially newborns. The highest incidence of nosocomial infections among pediatric patients is in children less than 1 year of age. The relative immaturity of the newborn's immune system, associated with routine ICU procedures that bypass the physical barriers of infection such as skin and mucous membranes, is responsible for the increased risk. Parenteral nutrition with high concentrations of glucose and lipids is another risk factor for infection. The fact that premature infants are most affected by these risk factors explains why neonatal ICUs have a higher incidence of nosocomial infections than pediatric ICUs [2, 4, 16]. Pediatric ICU is also unique in that each childhood has a different incidence depending on the type of nosocomial infection. In children under 5 years of age, the 3 most common nosocomial infections are in the following order: bloodstream infections, so-called bloodstream infections, pneumonia and urinary tract infections. In children aged 5 to 12 years, the 3 most common are nosocomial infections: pneumonia, bloodstream infections and urinary tract infections. In adolescents, the order of the most common nosocomial infections is: bloodstream infections, urinary tract infections, and then pneumonia [2, 4, 16]. Immunosuppressed patients after chemotherapy, human immunodeficiency virus infection, or steroid use are equally at risk for developing nosocomial infection.

Nosocomial infections do not have an apparent sex predilection.

Particular risk factors for the development of nosocomial infection are length of hospital stay and initial antibiotic therapy [17].

Staff shortages are a particular risk factor for the increased incidence of nosocomial infections, due to increased staff workload and poor hand hygiene [18].

Erythrocyte transfusion is a risk factor for the development of nosocomial infections in critically ill patients on ICU. In a prospective study, the incidence of nosocomial infection was 14.3% in patients with blood transfusions and 5.8% in patients without blood transfusions. In the group of patients with blood transfusions, there was a higher incidence of nosocomial infections, which was significant in seriously ill patients with a probability of survival of less than 25%. Patients with more than a 25% chance of survival had higher mortality, longer stays on the ICU, and longer hospitalizations compared with patients who did not receive a blood transfusion [19].

#### **5. Prevention**

It is not possible to eliminate all nosocomial infections, but one third of cases could be prevented if organized infection control programs were put in place.

Preventive measures can be divided into 2 categories, namely standard measures and transmission-based measures. Standard measures can always be used and are designed to prevent personnel from coming into contact with potentially infectious body fluids. The most important standard measure is hand hygiene. Washing hands with soap and water is considered the gold standard. The use of anhydrous antiseptic agents is accepted, but not in cases where visible dirt is present, proteinaceous body fluids such as blood, or spores contamination is suspected. In these cases, it is necessary to use soap and water. Hand hygiene must be observed before and after

the patient's examination, but also when gloves are worn. In case of contact with body fluids or secretions, it is advisable to use barriers such as gloves, masks, eye protectors and coats [2, 3].

Transmission-based measures aim to protect against the transmission of infectious micro-organisms from patients with a proven or suspected infection, as well as from patients colonized by specific micro-organisms. These additional measures are more than standard measures and are based on the path of transmission: contact, droplets, or airborne transmission.

Contact transfer measures apply to a wide range of micro-organisms that spread by direct contact with the patient or by indirect contact through contaminated objects such as toys, a stethoscope and unwashed hands. Preventive measures include, in addition to standard measures, isolation rooms for the patient or group, coats and gloves.

Droplet transfer measures are directed against microorganisms that spread a short distance from the patient by coughing and sneezing. These measures include isolation rooms for one patient or for a group of patients with the same microorganism. Healthcare professionals should wear masks with eye protection in addition to standard measures.

Measures to prevent airborne transmission include additional precautions against microorganisms which spread through the air stream. Patients should be isolated in rooms with ionized air. For other airborne microorganisms, a respirator is required when entering the patient's room. Isolation of a patient may be based on clinical symptoms or circumstances present on admission to the hospital and should always be initiated before isolating the microorganism [2, 3].
