WK 12- Infection Control Flashcards
What are core infection control components
- Hand hygiene
- Aseptic technique
- Standard & Transmission based precautions
- Environmental control
- Staff immunisation –Hep B, Influenza
- Monitoring of MDROs
What is a nosocomial infection
An infection for which there is no evidence that this was present or incubating at the time of hospital admission
What are the most common nosocomial infections
- Urinary tract infections -33%
- Pneumonia -15.5%
- Surgical wound infections -15%
- Primary bacteraemia -13% → mainly in those who are immune compromised (ie. Chemo patients)
- Others -23.5%
What organism is the most common cause of nosocomial infections
Staph aureus
What are current contemporary issues that hinder infection control
- Increase in highly complex and invasive medical and surgical procedures.
- A trend to large “mega” hospitals→ due to having high risk patients
- An overuse of broad spectrum antibiotics in hospital.
- The emergence of multiresistant organisms in hospitals.
- Immunosuppressive therapy
- The use of antibiotics as growth promoters in animal feeds→ used to enhance growth
- The increase in material and human costs of a patient acquiring a nosocomial infection (can also run out of options of how to treat patients due to reistance)
What are examples of multi-resistant organisms
- Methicillin resistant Staphylococcus aureus (MRSA)
- Vancomycin resistant Enterococci (VRE)
- Extended spectrum βlactamase (ESBL) producing organisms (usually Klebsiella pneumonia)
- Multiresistant gram negative bacilli (eg: Acinetobacter, Pseudomonas (pseudomonas is most common))
- CPE→ carbapenem resistant enterobacteriaciae
How do MRSA bacteria develop resistance
- Penicillin: Production of penicillinase (BlaZ)
- Methicillin: Production of PBP-2A (MecA)
What are the main major ICU infections
VAP= ventilator associated pneumonia Catheter associated blood strea infection Catheter related blood stream infection Catheter associated UTI Fever without a focus
What factors have encouraged the emergence of multi-resistant organisms
Hospital size and service provided→Bed numbers (multiple beds in single room makes it easier to spread nosocomial infections), transplantation (due to prior immune suppression), cardiac surgery
- Patient related factors→Underlying disease, immunosuppression, age, trauma, obesity
- Extrinsic factors→Invasive devices, surgical procedures, antibiotic pressures (more organisms someone is exposed to, greater risk of developing resistance)
- Environmental factors→contaminated air, water or food.
- Community acquisition→ travel (Asian countries→china, india), prison, ATSI, homeless
What is passive detection of antibiotic resistance
-“Passive” detection→ Isolates from clinical samples taken to determine the aetiology of a clinical episode of sepsis.
What is active detection of antibiotic resistance
-“Active” detection or surveillance→ Screening of patients in high risk areas, Surgical wound surveillance, Laboratory based surveillance
How can spread of nosocomial infections be reduced
- Education and ownership of infection control by ALL staff.
- The adoption and implementation of Standard and Additional precautions.
- The early identification and isolation of patients colonised or infected with multiresistant organisms
- Rational antimicrobial prescribing.
- Minimisation of the use of indwelling devices such as iv lines and urinary catheters (as bacteria form biofilms→ most likely pseudomonas and staph aureus)
- Basic hygiene
What factors contribute to nosocomial surgical wound infections
- Type of procedure→ orthopaedic is most common
- Pre-existing contamination of the area
- Duration of surgery and technical skill→ longer surgery=higher risk of infection
- Tissue viability
- Patient factors
- Duration of stay in hospital prior to surgery
What factors contribute to nosocomial line related infections
- Type of line (central vs peripheral)
- Duration (longer its in there= higher risk of infection)
- IV wound site care
- Infusate
- Use of coated lines (ie. Coated with antimicrobial)
What factors contribute to nosocomial resp infections
- Bypassing of normal defence mechanisms by mechanical ventilation.
- Patient factors
- Antibiotic selective pressure
- Cross infection in high risk units
What viruses are commonly involved in nosocomial infections
- blood borne viruses can spread in low income areas due to reusing needles (low resources)
- Influenza (A &B)
- Respiratory syncytial virus
- Varicella zoster (Chickenpox)
- Rotavirus
- Hepatitis A
- Hepatitis B
What is the risk of being exposed to; HIV, Hep C or Hep B if exposed to fluids in hospital
HIV= 0.3%
- Hep C= 3%
- Hep B= up to 30%
How can exposure to blood borne diseases be prevented in hosp
-minimised through the adherence to occupational exposure follow up protocol and implementation of risk minimisation processes following an exposure
What does sterilisation mean
Sterilisation is the process of killing or removing all viable organisms→ the use of physical or chemical procedures to destroy all microbial life, including large numbers of highly resistant bacterial endospores
-Done through→ Autoclaving, Dry heat, Gamma irradiation, Filtration, Low temp gas plasma H2O2 (Sterrad), Peracetic acid (Steris)
What does disinfection mean
Disinfection is the process of removing most but not all viable organisms→ microbial inactivation that eliminates virtually all recognized pathogenic micro-organisms but no necessarily all microbial forms (ie spores).
-Done through:
→Low level disinfection: Antiseptics (Phenols, Alcohol, Chlorhexidine, Iodine)
→High level disinfection: Boiling, Pasteurisation, Glutaraldehyde
What does infection mean
-Infection
-An invasion of pathogens or microorganisms into
the body that produces systemic illness or end
organ dysfunction
What does colonisation mean
-Colonisation
-Presence of microorganisms within a non-sterile
site that at present are not producing a systemic
illness or end organ dysfunction
What predisposes to candidiasis
- Diabetes
- Antibiotic Use
- Immunosuppresive med–> like steroids
What is the most common cause of septic arthritis
staph aureus
