الفهرس 
EPIDEMIOLOGY OF NOSOCOMIAL INFECTION IN ICUOnly 14 pages are availabe for public view
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Abstract
Between 5 to10% of patients who are admitted to ICUs acquire an infection during their admission.Data collected from 112 European medical ICUs between 1992 and 1997 indicated that NIs developed in 7.8% of hospitalized patients of 181,993 patients. UTIs (31%) were the most common, with 95% occurring in catheterized patients. Pneumonia, which was ventilator-associated in 86% of cases, represented 27% of all NIs, and bloodstream infections represented 19% of which 87% were found to be catheter-related.
The length of ICU stay is the predominant risk factor for nosocomial infection followed by the use of medical devices. Other risk factors include the patient’s underlying illness, selected medications, and the type of health care facility. In the EPIC study seven risk factors were determined for ICU-acquired infection: increased length of stay (more than 48 hours), mechanical ventilation, diagnosis of trauma, central venous catheterization, pulmonary artery catheterization, urinary catheterization, and stress ulcer prophylaxis.
The colonization of the host by potentially pathogenic may occur from exogenous or endogenous sources. The most common pathogens responsible for ICU infections are gram-positive organisms; coagulase-negative staphylococci (CoNS) were responsible for 42.9% of bloodstream infections, whereas S aureus was implicated in 27.8% of pneumonia cases. Methicillin-resistant S aureus (MRSA) and vancomycin-resistant enterococci have shown substantial increases in prevalence in both ICU and non-ICU hospital settings. gram-negative pathogen was P aeruginosa, which was associated with 18.1% of pneumonia cases ,also K pneumoniae, Enterobacter spp. associated with occurrence of pneumonia in the ICU between 1986 and 2003 .E coli isolates are urine samples (32.1%).
Several factors encourage the development and spread of resistance among pathogens in the surgical ICU as previous exposure to antibiotics, inappropriate use of antibiotics, particularly broad-spectrum agents, treatment in an ICU, length of hospital stay and poorly enforced infection control practices.
The relative prevalences of the 4 most common nosocomial infections in intensive care units (ICUs) in the United States -- pneumonia, bloodstream infections, urinary tract infections (UTIs), and surgical site infections changed between 1975 and 2003. Pneumonia and bloodstream infections increased in prevalence by approximately 5%, while UTIs and surgical site infections (SSTIs) decreased by approximately 40% and 15%, respectively. The prevalences of pneumonia and bloodstream infection and SSTIs are similar in both medical ICU and surgical ICU patients although UTIs are notably more common in the medical (30%) than the surgical (18%) ICU.
Prevention plays a major role in the control of NIs. First, methods and techniques are needed to prevent cross-contamination and to control the potential sources of pathogens that could be transmitted from patient to patient or from Health Care Worker (HCW) to patient. These methods and techniques include appropriate protocols for cleaning, disinfecting, and caring for various pieces of equipment and devices.
Soiled devices, linen, or clothing should be handled to prevent skin and mucous membrane exposure and transfer of microorganisms to the environment. Reusable devices should be cleaned and reprocessed according to hospital policy. Avoid recapping used needles Avoid removing used needles from disposable syringes by hand Avoid bending, breaking, or manipulating used needles by hand Place used sharp objects and needles in puncture-resistant containers.
Gawns should be used to protect skin and prevent soiling of clothing during procedures and patient-care activities likely to generate splashes or spray of blood, body fluid secretions, or excretions.
Mask, eye protection and face shield should be used to protect mucous membranes of the eyes, nose, and mouth during procedures and patient-care activities likely to generate splashes or sprays of blood, body fluid secretions, or excretions.
Gloves shoud be used for anticipated contact with blood, body fluid, secretion, excretions, and contaminated items for anticipated contact with mucous membranes and nonintact skin. Hand hygiene after direct contact with blood, body fluid, secretion, excretions, and contaminated items immediately before gloving and after glove removal between patient contacts and between dirty and clean body site contact in the same patient should be done.
Second, guidelines are needed for the appropriate use of surgical antibiotic prophylaxis or empirical therapy among selected groups of patients. Third, strategies to limit the emergence of resistant microorganisms need to be developed.
The frequency of contaminated hands with the different nosocomial pathogens, and the role of health care workers’ hands during outbreaks suggest that a hand hygiene preparation should at least have activity against bacteria, yeasts, and coated viruses. Centers for Disease Control and Prevention (CDC) guideline for hand hygiene in health care settings provides health care workers with a review of data on hand washing and hand antisepsis in health care settings and provides specific recommendations to promote improved hand hygiene practices and reduce the transmission of pathogenic microorganisms to patients and personnel in health care settings.
The best antimicrobial efficacy can be achieved with ethanol (60 to 85%), isopropanol (60 to 80%), and n-propanol (60 to 80%). The activity is broad and immediate. Ethanol at high concentrations (e.g., 95%) is the most effective treatment against naked viruses, whereas n-propanol seems to be more effective against the resident bacterial flora. The combination of alcohols may have a synergistic effect. The antimicrobial efficacy of chlorhexidine (2 to 4%) and triclosan (1 to 2%) is both lower and slower. Additionally, both agents have a risk of bacterial resistance, which is higher for chlorhexidine than triclosan. Their activity is often supported by the mechanical removal of pathogens during hand washing.
Taking the antimicrobial efficacy and the mechanical removal together, they are still less effective than the alcohols. Plain soap and water has the lowest efficacy of all. In the new Centers for Disease Control and Prevention guideline, promotion of alcohol-based hand rubs containing various emollients instead of irritating soaps and detergents is one strategy to reduce skin damage, dryness, and irritation. Irritant contact dermatitis is highest with preparations containing 4% chlorhexidine gluconate, less frequent with nonantimicrobial soaps and preparations containing lower concentrations of chlorhexidine gluconate, and lowest with well-formulated alcohol-based hand rubs containing emollients and other skin conditioners.
Too few published data from comparative trials are available to reliably rank triclosan. Personnel should be reminded that it is neither necessary nor recommended to routinely wash hands after each application of an alcohol-based hand rub. Long-lasting improvement of compliance with hand hygiene protocols can be successful if an effective and accessible alcohol-based hand rub with a proven dermal tolerance and excellent user acceptability is supplied, accompanied by education of health care workers and promotion of the use of the product.