Chapter 20 - Promoting Aspesis & Preventing Infection

Fundamentals of Nursing

Infection

When microorganisms capable of producing disease invade the body

The Spread of Infection: Six Links

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

Infectious agents

• Pathogens

• Normal flora that become pathogenic

• Reservoir

• Where pathogens live and multiply 

• May be living

  • Humans, animals, insects

  • May be nonliving

    • Food, floors, equipment, contaminated water

• Portal of exit

• Via

  • Bodily fluids 

  • Coughing, sneezing, diarrhea

  • Seeping wounds

• Tubes, IV lines Mode of transmission

• Contact

  • Direct: Touching, kissing, sexual contact

  • Indirect: Contact with a fomite

• Droplet: Cough, sneeze

• Airborne: Via air conditioning, sweeping

Portal of entry

• Eyes, nares, mouth, vagina, cuts, scrapes

• Wounds, surgical sites, IV or drainage tube sites

• Bite from a vector

Susceptible host

• Person with inadequate defense

• Four determining factors

  • Virulence

  • Organism’s ability to survive in the host’s environment

  • Number of organisms

  • Host’ defense

Stages of Infection

Incubation: From time of infection until manifestation of symptoms; can infect others

Prodromal: Appearance of vague symptoms; not all diseases have the stage

Illness: Signs and symptoms present

Decline: Number of pathogens decline

Convalescence: Tissue repair, return to health

Classifications of Infections

By location

Local

• Occurs in a limited region in the body (e.g., urinary tract infection)

Systemic

• Spread via blood or lymph

• Affects many regions (e.g., septicemia)

Classification of Infections by Duration

Acute: Rapid onset of short duration (e.g., common cold)

Chronic: Slow development, long duration (e.g., osteomyelitis)

Latent: Infection present with no discernible symptoms (e.g., HIV/AIDS)

Healthcare-Related Infection

An infection acquired as a result of healthcare

Cost of the healthcare system: $4.5 billion/year

Leading cause of death

Preventable with use of aseptic principles/techniques

Exogenous healthcare-related infection: Pathogen acquired from healthcare environment

Endogenous healthcare-related infection: Normal flora multiply and cause infection as a result of treatment 

Lines of Defense Against Infection

Primary defenses

Anatomical features, limit pathogen entry

• Intact skin

• Mucous membranes

• Tears

• Normal flora in gastrointestinal (GI) tract

• Normal flora in urinary tract

Secondary defenses

Biochemical processes activated by chemicals released by pathogens

• Phagocytosis

• Complement cascade

• Inflammation

Fever Tertiary defenses

Humoral immunity

• B-cell production of antibodies in response to an antigen

Cell-mediated immunity

• Direct destruction of infected cell by T cells

Factors That Increase Infection Risk

Developmental stage

Breaks in the skin

Illness/injury, chronic disease'

Smoking, substance abuse

Multiple sex partners

Medications that inhibit/decrease immune response

Nurisng/medical procedures

Factors That Support Host Defenses

Adequate nutrition

• To manufacture cell of the immune system

Balanced hygiene

• Sufficient to decrease skin bacterial count

• Not overzealous; causing skin cracking

Rest/exercise

Reducing stress

Immunnization

Preventing Infection: Implementing Medical Asepsis

Medical asepsis

“A state of cleanliness that decreases the potential for the spread of infections”

Promoted through

• Maintaining a clean environment

• Maintaining clean heads

• Following guidelines from the Centers for Disease Control and Prevention (CDC)

Maintaining a Clean Environment

Clean spills and dirty surfaces promptly.
Remove pathogens through chemical means (disinfect).
Remove clutter.
Consider supplies brought to the client room as contaminated.
Consider items from the client’s home as contaminated.

Wash Your Hands

When you arrive in the unit
When you leave the unit
Before and after restroom use
Before and after client contact
Before and after contact with client belongings
Before gloving
After glove removal
Before and after touching your face
Before and after eating
After touching a contaminated article
When you see visible dirt on your hands

Handwashing Guidelines

Wash for at least 20 sec in nonsurgical setting; 2 to 6 min in surgical setting.
Remove jewelry and clean beneath fingernails.
Use a bactericidal solution or use water if hands are visibly soiled.
Use warm water, not hot.
Apply soap to wet hands.
Use friction.
Rinse soap.
Towel or hand dry.

Implementing CDC Guidelines

Standard precautions

Protects healthcare workers from exposure

Decrease transmission of pathogens

Protects from pathogens carried by healthcare workers

Transmission- Based Precautions

Contact precautions
• Pathogen is spread by direct contact.
Sources of infection: Draining wounds, secretions, supplies
Precautions include
• Possible private room
• Clean gown and glove use
• Disposal of contaminated items in room
• Double-bag linen and mark

Airborne precautions
• Pathogen is spread via air currents.
Transmission via ventilation systems, shaking
sheets, sweeping
Precautions include
• Same as those for contact, with addition of special room, special
mask, and mask for patient when transported
Droplet precautions
• Pathogen is spread via moist droplets.

• Coughing, sneezing, touching contaminated objects

• Precautions include
  • Same as those for contact
  • Addition of mask and eye protection within 3 ft of client

Protective Isolation

“Protective environment”
• Protects the client from organisms
• Used in special situations with immune-
compromised client population
Precautions include
• Room with special ventilation and air filters; no
carpeting; daily wet-dusting
• Avoiding standing water in the room (e.g.,
humidifier)
• Nurse not assigned to other clients with active
infection
• Standard and transmission-based precautions,
plus mask and other personal protective
equipment (PPE) (to protect patient)

Implementing Surgical Asepsis

Includes
• Creation of a sterile environment
• Use of sterile equipment/supplies
• Sterilization of reusable supplies
• Surgical hand scrub
• Surgical attire
• Sterile gloves
• Sterile field
• Use of sterile technique