Harelle Final CH7

• Microorganisms


  Include nonpathogenic and parasitic life forms
• Purpose of microorganisms


  Through process of decay, convert organic compounds into more simple forms
• Beneficial microorganisms


  Yogurt, beer, cheese, antibiotics
• Indigenous microflora


  Live on skin and inside the human body, harmless unless given opportunity to enter a different part of the body (surgical incision), where they become pathogens
• Categories of symbiosis


  • Mutualism
  • Commensalism
  • Parasitism
• Mutualism


  Both organisms benefit and depend on one another (e.g. E-coli colonize within the human intestines)
• Commensalism


  One organism benefits, the other is not harmed (e.g. indigenous microflora on the skin of humans obtain nutrients)
• Parasitism


  One organism benefits and the host is harmed (e.g. intestinal worms)
• Pathogens


  Microorganisms that cause an infection
• Pathogens


  • Commensal microbes that become opportunistic by entering a surgical skin incision
  • Airborne viruses, such as the virus that causes the common cold
• Infection


  Multiplication of organisms in the tissues of a host
• Nosocomial Infection/Health-care Associated Infections (HAIs)


  Any infection that develops while a patient is in a health care facility
• HAI statistics in 2011
• Primary goal of surgical team
• Bacteria classification based on characteristics


  • Aerobic or anaerobic
  • Spore-forming
  • Pathogenicity
  • Staining
  • Gram stain
• Prokaryotes


  Divide by binary fission
• Staphylococcus aureus


  Most commonly transmitted pathogen in the operating room, can come from patient or surgical personnel, causes infections like toxic shock syndrome, osteomyelitis, endocarditis, postop SSI's
• Staphylococcus epidermis


  Causes IV catheter infections, UTI's, prosthetic device infections, sub-acute bacterial infections, endocarditis
• Streptococcus pneumoniae


  Causes pneumonia, meningitis, otitis media, bacteremia
• Streptococcus pyogenes


  Causes strep throat, tonsillitis, rheumatic fever, scarlet fever, necrotizing fasciitis
• Aerobic pathogens


  • Bordetella pertussis - Whooping cough
  • Neisseria meningitides - Bacterial meningitis
  • Bacillus anthracis - Anthrax
  • Listeria monocytogenes - Meningitis, bacteremia
  • Corynebacterium diphtheriae - Respiratory and cutaneous diphtheria
• Anaerobic pathogens


  • Clostridium perfringens - Gas gangrene, cellulitis, fascitis
  • Clostridium difficile - Antibiotic-associated GI diseases
  • Haemophilus influenzae - Bacterial meningitis, respiratory tract infections, bacterial pneumonia
  • Escherichia coli - UTI's, sepsis, neonatal meningitis
• Tuberculosis


  Caused by Mycobacterium tuberculosis, transmitted through airborne droplet nuclei, usually infects the lungs but may also infect other organs
• Viruses


  Nonliving particles reliant on host cell for survival, enter the body through inhalation, exchange of body fluids, ingestion, arthropod bites
• Process of viral infection: sneeze - uninfected person exposed - cells grow and lyse - spread of infection
• Surgical Technologist may encounter viruses in the OR (HBV, HIV), can be infected by exposure from a patient, and can also pass an infection to a patient
• Follow hospital policies and procedures and use Standard Precautions to minimize risks of disease transmission, all body fluids should be considered potentially infectious
• Emerging infectious diseases


  Increased amounts, causes: mobility of humans, increased amounts of bacterial multidrug–resistant (MDR) strains, and ability to mutate
• Emerging infectious diseases


  • Methicillin-resistant Staphylococcus aureus (MRSA)
  • Vancomyocin-resistant Staphylococcus aureus (VRSA)
  • Multidrug-resistant Mycobacterium tuberculosis
  • Viruses that mutate and evolve (hemorrhagic fevers: Ebola, Dengue, Marburg, Lassa)
• Prion


  Proteinaceous infectious particle, nonliving protein strands that do not contain DNA or RNA, attack the brain
• Creutzfeldt-Jacob Disease (CJD)


  Rare, can be inherited, transmitted through contaminated surgical instruments or tissue transplantation, develops slowly with incubation up to 20 years, early symptoms mimic Alzheimer's, later stages characterized by dementia and progressive loss of physical functions
• Parasites


  Invertebrates that cause disease, including helminths (worms) and protozoa
• Fungi


  Eukaryotic organisms that are either unicellular yeasts or multicellular molds and mushrooms, opportunistic fungal infections common in AIDS patients
• Natural lines of defense


  Skin, immune response, immunity
• Safe work practices


  Hand hygiene, PPE's, respiratory hygiene, safe injection procedures, safe handling of contaminated items
• Transmission-based precautions

  Guidelines for infection control and prevention of cross contamination of patients with a diagnosed disease process
• Methods of transmission


  Any infection requires a primary agent (bacterium, virus, fungus, or parasite)
• Handwashing technique

  Friction, circular motion, interlacing fingers to clean web spaces, 30 seconds to one minute
• Precautions that apply to modes of transmission


  • Contact (direct and indirect)
  • Airborne
  • Droplet
• Sources of surgical site infections


  • Exogenous: surgical personnel, human error and lapses in sterile technique, environment (fomites, vectors, unsterile dressings/instruments)
  • Endogenous: patient flora encountered in contaminated procedures, resident flora of the skin