Chapter 26 Infection Control

26-2 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Infection Control  Infection control practices are directed at controlling or eliminating sources of infection in the health care agency, home, or community.

26-3 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Pathogens, Infection, and Colonization  Pathogenicity is the ability of a microorganism to produce disease.  Microorganisms that cause diseases in humans are called pathogens.  Virulence is the degree of pathogenicity of an infection’s microorganism.

26-4 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Pathogens, Infection, and Colonization  Infection is an invasion and multiplication of microorganisms in body tissue that results in cellular injury.  These microorganisms are called infectious agents.

26-5 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Pathogens, Infection, and Colonization  Communicable Disease The result of a communicable agent being transmitted to a client by direct or indirect contact, through a vehicle (or vector) or airborne route

26-6 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Pathogens, Infection, and Colonization  Colonization is the multiplication of microorganisms on or within a host that does not result in cellular injury.  Flora are the vegetation of microorganisms on the human body. Resident flora Transient flora

26-7 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Agent, Host, and Environment  Agents capable of causing disease: Biological agents Chemical agents Physical agents

26-8 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Agent, Host, and Environment  A host is a simple or complex organism that can be affected by an agent. A susceptible host is a person who lacks resistance to an agent. A compromised host is a person whose normal defense mechanisms are impaired and who is therefore susceptible to infection.

26-9 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Agent, Host and Environment  The environment consists of everything other than the agent and host. Water, food, plants, animals Housing conditions Noise Meteorological conditions Environmental chemicals

26-10 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Chain of Infection  Microorganism (infectious agent)  Source or reservoir  Portal of exit from reservoir  Mode of transmission  Portal of entry into host  Susceptible host

26-11 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Infectious Agents (Microorganisms)  Agents that produce infections can consist of bacteria, viruses, fungi, protozoa, and rickettsia

26-12 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Infectious Agents  The ability of a microorganism to infect a client is related to: Virulence of the agent Number of microorganisms present Ability of the agent to enter and live in the client Susceptibility of the client

26-13 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Infectious Agents  Resident Infectious Agents Microorganisms which are always present on skin. Can be reduced through handwashing, but not totally removed.

26-14 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Infectious Agents  Transient Infectious Agents Agents that are picked up by the skin from another person or object. Attach themselves to the skin and then may be transmitted to a susceptible host.

26-15 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Source or Reservoir  Required for the microorganism to survive while awaiting a host.  May allow the organism to multiply, making it more dangerous. The human body is the most common reservoir. Food, plants, animals, and feces are other common reservoirs.

26-16 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Portal of Exit  Pathway by which pathogens leave the body of a host. Accessed by: Direct Contact Indirect Contact Airborne Transmission

26-17 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Portal of Exit  Direct Contact Transmission of disease from the host Touching, kissing, and sexual intercourse  Sources of Direct Contact Skin, mucus membranes, urine, feces, reproductive tract, blood

26-18 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Portal of Exit  Indirect Contact Occurs with the use of vehicles and vectors  Vehicles (fomites) Toys, hospital supplies, instruments, dishes, cups, or surgical dressings, food, fluids, blood

26-19 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Portal of Exit  Airborne Transmission Transmission of infectious agents through coughing, sneezing, dust particles Usually entry via the person’s respiratory tract

26-20 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Portal of Entry  Pathway by which infectious agents gain access to the body

26-21 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Susceptible Host  A person with a reduced immune response has increased susceptibility.  The immune response is the body’s natural defense against infection.

26-22 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Factors Influencing Production of an Infectious Disease  Age  Heredity  Stress  Surgery  Nutrition  Health Status

26-23 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Factors Influencing Production of an Infectious Disease  Age The elderly and children under two years of age are at greatest risk.  Heredity Conditions or diseases resulting in the absence of or inability to form immune defenses.

26-24 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Factors Influencing Production of an Infectious Disease  Stress Increase in metabolic rate which results in using up stored energy Elevation of blood cortisol, decreasing anti- inflammatory responses Continued stress produces exhaustion, further depleting ability to ward off infection.

26-25 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Factors Influencing Production of an Infectious Disease  Surgery Eliminates primary barrier of infection. Predisposes clients to surgical site infections. Localized infection at wound site can progress to a systemic infection. Additional risks include catheters and tubes.

26-26 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Factors Influencing Production of an Infectious Disease  Nutrition Insufficient protein consumption reduces antibody production and inhibits the body’s ability to ward off infection.  Health Status Clients with disease of their immune system are at greater risk. Chronic diseases can predispose the client to infection.

26-27 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Normal Defense Mechanisms  Nonspecific and specific immune defenses work in harmony to defend the host from pathogens.

26-28 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Normal Defense Mechanisms  Nonspecific Immune Defenses Protect the host from all microorganisms Not dependent on prior exposure to the antigen

26-29 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nonspecific Immune Defenses  Skin and Normal Flora  Mucous Membranes  Sneeze, Cough Reflexes  Tearing Reflexes  Elimination  Acidic Environment  Inflammatory Response

26-30 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nonspecific Immune Defenses  Skin Intact skin is the body’s first line of defense against infection. Sebum is produced by the skin and contains fatty acids that kill some bacteria.

26-31 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nonspecific Immune Defenses  Normal Flora Normal flora residing on the skin compete with pathogenic flora for food and inhibit their multiplication. Inappropriate antibiotic use may disrupt the balance of normal flora.

26-32 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nonspecific Immune Defenses  Mucous Membranes Mucus entraps infectious agents and contains substances that inhibit bacterial growth. Cilia trap and propel mucus and microorganisms away from the lungs.

26-33 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nonspecific Immune Defenses  Sneeze and Cough Reflexes Physically expel mucus and microorganisms from the respiratory tract and oral cavity with force  Tearing Reflex Protects the eyes by continually flushing away microorganisms

26-34 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nonspecific Immune Defenses  Elimination Patterns and Acidic Environment Resident flora of the large intestines Mechanical process of defecation Flushing action of urination Acidic environment of urine and vagina

26-35 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nonspecific Immune Defenses  Inflammatory Response Tissue injury caused by bacteria, trauma, chemicals, heat, or any other phenomenon Release of substances that produce secondary changes in the tissue

26-36 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Specific Immune Defense (The Immune Responses)  Immunity is a specific defense mechanism that creates an immune response to a specific invading antigen.

26-37 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Specific Immune Defense (The Immune Responses)  Immune Responses Active immunity Passive immunity Acquired immunity Natural immunity Artificial immunity

26-38 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Immune Responses  Active immunity results from the development within the body of antibodies that neutralize the infective agent.  Passive immunity is acquired by the introduction of preformed antibodies.

26-39 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Immune Responses  Acquired immunity results either from exposure to an antigen or from the passive injection of immunoglobulins.  Natural immunity refers to the genetically determined response of protection within a specific species.  Artificial immunity is produced following a vaccine.

26-40 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. The Humoral Immune Response  B lymphocytes recognize the antigen as an enemy.  Immunoglobulins are plasma protein cells that produce five different classes of antibodies (IgM, IgG, IgA, IgD, and IgE).  Immunoglobulins circulate throughout the bloodstream for the purpose of destroying antigens.

26-41 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Cell-Mediated Immunity  Fights pathogens that survive inside cells.  Antigen stimulates the release of activated T cells. T-helper cells T-suppressor cells T-cytotoxic cells

26-42 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Localized Versus Systemic Infections  Infection results from tissue invasion and damage by an infectious agent. Localized infections are limited to a defined area or single organ. Systemic infections affect the entire body and involve multiple organs.

26-43 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Four Stages of Infection  Incubation  Prodromal  Illness  Convalescence

26-44 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nosocomial Infections  Infections acquired in a health care setting that were not present or incubating at the time of the client’s admission

26-45 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Common Sites of Nosocomial Infections  Urinary tract  Surgical sites  Respiratory tract

26-46 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Nosocomial Infections  Procedures identified as possible sources of infection are: Inadequate handwashing Catheterization technique Improper suctioning technique Improper dressing-change technique Contamination of closed drain system

26-47 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Infection Chain  Breaking the chain of infection; preventive measures follow each critical link in the chain of infection.

26-48 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Asepsis  Asepsis is the absence of microorganisms.  Aseptic technique is the infection control practice used to prevent the transmission of pathogens.

26-49 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Medical Asepsis (Clean Technique)  Practices to reduce the number, growth, and spread of microorganisms The most common cause of nosocomial infections is contaminated hands of health care providers. Wash hands before and after every client contact.

26-50 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Surgical Asepsis (Sterile Technique)  Practices that eliminate all microorganisms and spores from an object or area Surgical scrub Surgical attire Sterile fields Sterile instruments and equipment

26-51 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Reduce or Eliminate Infectious Agents  Infection control practices to break the chain of infection Cleansing Disinfection Sterilization

26-52 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Reduce or Eliminate Infectious Agents  Cleansing Removal of soil or organic material from instruments and equipment used in providing care Water, mechanical action, detergent

26-53 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Reduce or Eliminate Infectious Agents  Disinfection Elimination of pathogens, except spores, from inanimate objects Use of germicides and antiseptics.

26-54 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Reduce or Eliminate Infectious Agents  Sterilization Methods used for total elimination of all microorganisms including spores are: -Moist heat or steam (autoclave, boiling water) -Radiation -Chemicals -Ethylene oxide gas

26-55 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Reduce or Eliminate Infectious Agents  Home Health Care Considerations Adapting acute care infection control practice to the home care setting involves: -Cleaning and disinfecting equipment -Using clean versus sterile technique -Handling of the nursing supply bag

26-56 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Reduce or Eliminate Infectious Agents  Disposal of Infectious Waste in the Home  Biological Hazard Symbol  OSHA Regulations

26-57 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Guidelines for Standards Precautions  Barrier Precautions Use of masks, gowns, and gloves to minimize the risk of exposure to blood and body fluids

26-58 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Guidelines for Standards Precautions  Body Substances Blood All body fluids Secretions Contaminated items regardless of whether or not they contain visible blood Nonintact skin Mucous membranes

26-59 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Role of Health Care Personnel and Health Agencies in Infection Control  Mask and eye protection or face shield  Non-sterile gown  Tuberculosis masks  Isolation precautions initiated when positive cultures from a draining wound are reported

26-60 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Role of Health Care Personnel and Health Agencies in Infection Control  This nurse is interacting with a client who requires isolation precautions.

26-61 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Role of Health Care Personnel and Health Agencies in Infection Control  Reinforce adherence to isolation.  Post signs indicating type of isolation.  Provide necessary supplies.  Place clients in a private room with adequate ventilation.  Use disposable supplies and equipment.

26-62 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Role of Health Care Personnel and Health Agencies in Infection Control  Labeling of all articles leaving the room  Use of impermeable bags or double bagging  Client and family instruction  Alert to psychological discomfort

26-63 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Role of Health Care Personnel and Health Agencies in Infection Control  Blood Borne Pathogen Exposure OSHA requires that all health agencies make available the hepatitis B vaccine and vaccination series to all employees.

26-64 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Role of Health Care Personnel and Health Agencies in Infection Control  Exposure Control Plan Begins with standard precautions and moves to postexposure prophylaxis Specific follow-up for blood-borne pathogens Postexposure prophylaxis only in cases of highest risk

26-65 Copyright 2004 by Delmar Learning, a division of Thomson Learning, Inc. Alternative Therapies Used to Treat Infections  Herbal Products Antimicrobial action Augment and vitalize the body’s own defenses  Client’s alternative practices should be documented.  Possible adverse reactions are possible when used with prescribed drugs.