Hospital-Acquired Infections Lecture 6 PDF

LECTURE 6 Hospital- acquired infections Health care-associated infections (HAIs) Hospital Acquired Infections Nosocomial infections  Healthcare Associated Infection nt Pa t ie t ie...

LECTURE 6 Hospital- acquired infections Health care-associated infections (HAIs) Hospital Acquired Infections Nosocomial infections  Healthcare Associated Infection nt Pa t ie t ie pa nt to to W HC HC W Patient to Patient  Definition: An infection acquired by a patient in a hospital (or other healthcare facilities e.g. Nursing home or Rehabilitation center) which was not present or incubating at admission. Infections occurring more than 48 hours after admission are usually considered HAIs. It is a serious problem in the hospitals. Each hospital should have an infection control (IC) program designed to prevent acquiring of infections. Factor Favouring Healthcare Associated Infections Host factors Microbial factors Factor Favouring Healthcare Associated Infections Host Factors: Extreme of age (neonates & elderly) Lowered resistance Instrumentation e.g. using urinary catheters, ventilators, endoscopes, venous and arterial catheters. Factor Favouring Healthcare Associated Infections Host factors Microbial factors  Factor Favouring Healthcare Associated Infections Microbial factors The hospital environment harbours highly virulent organisms e.g. S. aureus, Klebsiella spp &Pseudomonas spp The wide use of antibiotics in the hospital favours development of resistance to antibiotics e.g. MRSA. Opportunistic pathogens may cause infection in immunosuppressed patients. Stages of the infectious process  Stages of the infectious process 1. Source of man (case or carrier), environment, animals and birds infection 2. Mode of airborne, droplet inhalation, ingestion, injection, insects, transmission contacts, transplacental 3. Portal of entry respiratory tract, gastrointestinal tract, skin 4. Portal of exit urine, stools, blood, respiratory or genital discharge Source of infection 1. Endogenous: the organism is acquired from the patient’s own normal flora. 2. Exogenous: People: either infected patients or medical personnel Hospital environment: e.g. instruments, ventilators, bedpans, and air condition system Blood and blood products  Stages of the infectious process 1. Source of man (case or carrier), environment, animals and birds infection 2. Mode of airborne, droplet inhalation, ingestion, injection, insects, transmission contacts, transplacental 3. Portal of entry respiratory tract, gastrointestinal tract, skin 4. Portal of exit urine, stools, blood, respiratory or genital discharge Modes of transmission 2. Droplet 1. Contact Blood or.6 needle prick Airborne.3 4. Common Vector.5 vehicle Modes of transmission I. Contact: Direct contact by hands of healthcare personnel Indirect contact by contaminated objects e.g. thermometers  Modes of transmission II. Droplet Droplets containing microorganisms are generated from infected individuals during coughing, sneezing and talking. Droplets are large >5μm-----travel short distance (within one meter) and settle down rapidly. Transmission requires close contact COVID 19 Influenza Mumps Rubella Meningococcal meningitis  Modes of transmission III. Airborne Droplet nuclei containing microorganisms are generated from evaporated droplets Droplet nuclei are small (< 5μm)→ remain suspended in air for long periods and can be carried for long distances. Transmission does not require close contact Tuberculosis Measles Chickenpox Anthrax Droplet and Airborne Transmission Modes of transmission IV. Blood or needle prick V. Common vehicle Transmission may occur by contaminated items such as food, water, medication, multi-dose vials and instruments. VI. Vector The infectious agents may be transmitted through insects e.g. mosquitoes.  Stages of the infectious process 1. Source of man (case or carrier), environment, animals and birds infection 2. Mode of airborne, droplet inhalation, ingestion, injection, insects, transmission contacts, transplacental 3. Portal of entry respiratory tract, gastrointestinal tract, skin 4. Portal of exit urine, stools, blood, respiratory or genital discharge  Urinary tract infections (UTIs) e.g. by E. coli, Klebsiella, Pseudomonas and Proteus Surgical site infections (SSIs) e.g. by staphylococci, Gram negative bacilli and Common enterococci types of Lower respiratory tract infections (LRTIs) HAIs e.g. by S. aureus and Gram negative bacilli Blood stream infections (BSIs) e.g. staphylococci, Gram negative bacilli and enterococci  1.Urinary tract infections (UTI) Is an infection in any part of the urinary system, including the urethra, bladder, ureters, and kidneys. About 75% of UTIs developed in hospitals are associated with a urinary catheter (Catheter associated UTI… CAUTI). 15-25% of hospitalized patients use urinary catheters. CAUTIs are associated with increased morbidity, mortality, healthcare costs, and length of stay. CAUTIs are one of the most common types of healthcare- associated infections (HAIs). They are preventable and treatable.  1.Urinary tract infections (UTI) E. coli is the commonest cause. Main predisposing factor: A procedure performed in the hospital as bladder catheterization, cystoscopy, ureteric catheterization Source of infection: 1.Endogenous: The most common and comes from patient’s normal flora. 2.Exogenous: Less common Hospital Environment  Cross infection  Prevention of catheter-associated urinary tract infection Before Insertion: Wash hands with alcohol hand rub. Put on sterile gloves. During insertion: Be sure not to touch the hands of the operator or the skin of the patient; “no touch” technique. Apply chlorhexidine or betadine solution to the distal urethra and genetalia Insert 2-3 ml of the lubricant (e.g. anesthetic jelly into the urethra) to prevent trauma which predispose to infection  Prevention of catheter-associated urinary tract infection After Insertion: Check the clinical indication why the urinary catheter is in situ. Check the catheter has been continuously connected to the drainage system. Patient education to ensure routine daily meatal hygiene is performed. Regularly empty urinary bags, each into a clean container. Perform hand hygiene and wear gloves prior to each catheter care procedure.  Urinary tract infections (UTIs) e.g. by E. coli, Klebsiella, Pseudomonas and Proteus Surgical site infections (SSIs) e.g. by staphylococci, Gram negative bacilli and Common enterococci types of Lower respiratory tract infections (LRTIs) HAIs e.g. by S. aureus and Gram negative bacilli Blood stream infections (BSIs) e.g. staphylococci, Gram negative bacilli and enterococci  2.Surgical Site Infection (SSI) A surgical site infection (SSI) is an infection in the part of the body where a surgery took place. In low- and middle-income countries, 11% of patients who undergo surgery are infected in the process. SSIs lead to increase hospital stay and costs. Many of the SSIs can be prevented through application of infection control measures.  Factors affecting occurrence of (SSIs) The surgical team: A skilled team will conduct an operation in a minimal time with gentle handling of tissue and good hemostasis. Duration of operation: The longer the operation, the higher the risk of developing an infection The patient’s condition: good general health and good immune status reduce the incidence of wound sepsis. Antibiotic chemoprophylaxis: suitable antibiotic administered before and during the operation can greatly reduce the incidence of sepsis.  Factors affecting occurrence of (SSIs) Post operative wound care: special care should be taken during dressing t o prevent wound contamination. The presence of a foreign body : Presence of prosthesis in a joint or a prosthetic heart valve encourages infection Wound Type: 1. Clean wounds 2. Clean/contaminated wounds 3. Contaminated wounds 4. Dirty wounds  Urinary tract infections (UTIs) e.g. by E. coli, Klebsiella, Pseudomonas and Proteus Surgical site infections (SSIs) e.g. by staphylococci, Gram negative bacilli and Common enterococci types of Lower respiratory tract infections (LRTIs) HAIs e.g. by S. aureus and Gram negative bacilli Blood stream infections (BSIs) e.g. staphylococci, Gram negative bacilli and enterococci  III. Lower Respiratory tract Infection Lower respiratory tract infections (LRTIs) are associated with increased morbidity and mortality in hospitalized patients. It is the second or third most common type of hospital-acquired infection (HAI) after urinary tract infection and surgical site infection. Ventilator-associated pneumonia (VAP) is the most serious type of (LRTI) VAP is a lung infection that develops in a person who is on a ventilator.  Predisposing factors to VAP Elderly debilitated patients or young children. Comatosed patients Prolonged ICU stay Prior administration of antibiotics Patients who receive general anesthesia, steroids or immunosuppressive therapy Heavy smokers  Prevention of VAP The VAP bundle has key components aiming to prevent VAP: Elevation of the Head of the Bed Daily Sedative Interruption & Assessment of Readiness to Extubate Daily Oral Care with Chlorhexidine  Urinary tract infections (UTIs) e.g. by E. coli, Klebsiella, Pseudomonas and Proteus Surgical site infections (SSIs) e.g. by staphylococci, Gram negative bacilli and Common enterococci types of Lower respiratory tract infections (LRTIs) HAIs e.g. by S. aureus and Gram negative bacilli Blood stream infections (BSIs) e.g. staphylococci, Gram negative bacilli and enterococci  IV. Blood stream infections Catheter-related bloodstream infection (CRBSI) is defined as the presence of bacteremia originating from an intravenous catheter. It is one of the most frequent, lethal, and costly complications of central venous catheterization.  Prevention of CRBSI The central line bundle has five key components: Hand hygiene Maximal barrier precautions Chlorhexidine skin antisepsis Optimal catheter site selection, with avoidance of using the femoral vein for central venous access in adult patients Daily review of line necessity, with prompt Infections in intensive care units (ICUs)  Infections in ICUs Patients in ICU have impaired defense (general & local) mechanisms against infection due to their condition and invasive procedures. Thus, they are more likely to have all types of nosocomial infections. They are accommodated in a relatively small area where numerous procedures are carried out increasing the risk of cross infection. Moist equipment (ventilators, humidifiers, suction apparatus) and solutions become easily contaminated and act as vehicles for Gm negative bacteria THANK YOU