Infection Control Principles

Infection Control Objectives

• Students should be able to discuss the body's normal defenses against infection
• Apply principles of medical and surgical asepsis
• Analyze the chain of infection
• Apply principles of infection control precautions
• Discuss the role of an infection control nurse

Infection Control Outlines

• Definitions
  • Infection control: set of methods to control and prevent disease spread
  • Infections: caused by pathogens (germs)
  • Communicable disease: spreads from one person to another
  • Infectious disease: caused by a pathogen (germ or bacteria)
  • Contaminated: dirty, soiled, unclean
  • Disinfection: cleaning to destroy germs (pathogens)
  • Mode of transmission: way germs are passed
• The body's normal defenses against infection
  • Nonspecific defenses
    • Normal body flora (normal bacteria)
    • Normal body system defenses
    • Inflammation process
  • Specific defenses
    • Immune response
• Asepsis
  • Free from all living microorganisms
  • Major process for controlling infection
  • Aseptic technique: effort to keep patients free from exposure to infectious pathogens
  • Forms of asepsis
    • Medical asepsis (clean technique)
    • Surgical asepsis
• Principles of Surgical Asepsis
  • Sterile item touching non-sterile item becomes contaminated
  • Partially unwrapped sterile packages are contaminated
  • Sterile item in question is considered unsterile
  • Commercially packaged sterile items are not sterile after expiration date
  • Opened sterile item is contaminated
  • Wet sterile item is unsterile
  • Coughing, sneezing, excessive talking over sterile field causes contamination
  • Reaching across sterile equipment contaminates
  • Sterile items below waist level are contaminated
• The process of sterilization
  • Physical sterilization methods:
    • Radiation (e.g. ultraviolet)
    • Boiling water
    • Free-flowing steam
    • Dry heat
    • Steam under pressure (autoclave)
  • Chemical sterilization: antiseptic chemical solutions

Chain of Infection

• Infectious agent
• Reservoir
• Portal of entry
• Mode of transmission
• Portal of exit
• Susceptible host

Infection Control Precautions

• Two major categories
  • Standard precautions
  • Transmission-based precautions (isolation precautions)

Standard Precautions

• Combined methods from universal precautions and body substance isolation
• Wash hands after touching blood, body fluids
• Wash hands after gloves are removed
• Wear clean, non-sterile gloves
• Wear mask and eye protection and gown
• Hand hygiene is key

Transmission-Based Precautions

• Measures to control spread of infection from patients known or suspected of being infected

Role of the Infection Control Nurse

• Providing staff education
• Reviewing infection control policies and procedures
• Reviewing patient records and laboratory reports
• Consulting with occupational health (e.g., TB testing)
• Gathering statistics on nosocomial infections (hospital-acquired)
• Notifying public health of communicable diseases
• Educating patients and families
• Identifying infection control problems with equipment
• Communicating with hospital and community health care personnel

Infection Control (Benefits)

• Reducing morbidity and mortality
• Reducing healthcare costs
• Improving healthcare service quality
• Based on risk assessment and risk management
• Easy application of principles
• Protecting healthcare workers

WHO Does Infection Control?

• Every healthcare facility needs a nominated person or team to ensure policies and procedures are in place
• All employees with patient contact must adhere to policies and procedures

Hand Hygiene

• Single most important practice to reduce transmission of infectious agents
• Includes:
  • Handwashing with antiseptic soap and water
  • Alcohol-based products (gels, rinses, foams) without water

Types of PPE

• Gloves
• Isolation gowns
• Face protection (masks, goggles, face shields)
• Respiratory protection (e.g., respirator with N95)
• Boots

Standard Precautions (Details)

• Prevent transmission of common infectious agents
• Handwashing is key
• Assume infectious agents could be present in patient's:
  • Blood
  • Body fluids, secretions, excretions (except sweat)
  • Non-intact skin
  • Mucous membranes

PPE for Standard Precautions

• Touching respiratory secretions, contaminated items, blood or body fluids
• Soiled clothes with patient fluids, secretions, or excretions
• Possible splashes/sprays of blood, body fluids, secretions, and excretions

Transmission-Based Precautions (Types)

• Contact transmission
• Droplet transmission
• Airborne transmission

Airborne Transmission

• Very small particles of evaporated droplets or dusts with infectious agents
• Remain in air for long time
• Travel further than droplets
• Examples: Tuberculosis, Measles, Chickenpox

Airborne Precautions

• Preventing spread of infection through inhaled airborne particles
• Patient in isolation
• Patient in airborne isolation room
• Patient wears mask outside isolation room

Contact Transmission

• Direct contact (no intermediate)
  • Host in contact with reservoir (e.g., MRSA)
  • Skin-to-skin contact (e.g., scabies, herpes)
• Indirect contact (intermediate)
  • Disease carried from reservoir to host (infected or colonized person or object)
  • Contaminated surfaces (e.g., electronic thermometers, glucose monitors)

Contact Precautions

• Isolate or cohort patients
• Gown and gloves for patient contact (remove immediately)
• Don't touch eyes, nose, mouth with hands
• Avoid contaminating environmental surfaces
• Wash hands immediately after patient contact
• Clean and disinfect patient room daily, bed rails, bed side tables, toilet surfaces, and other equipment