Chapter 10: Asepsis

Microorganisms Living animals or plants visible only with a microscope; also commonly called germs The body’s immune defense mechanisms eliminate them They reside within the body without causing disease They cause an infection or infectious disease

Types of Microorganisms Fungi Helminths Rickettsiae Prions Bacteria Protozoans Viruses Mycoplasmas

Categorization of Microorganisms Nonpathogens: harmless, beneficial Pathogens: cause illness Resident nonpathogens constantly present on the skin Transient pathogens picked up during contamination Aerobic: require oxygen to live Anaerobic: exist without oxygen

Survival of Microorganisms Spores Temporarily inactive microbial life form; can resist heat and destructive chemicals and survive without moisture; reactivate and reproduce when conditions are favorable Antibiotic-resistant bacterial strains No longer respond to drugs that once were effective against them

Question Is the following statement true or false? Transient pathogens are present constantly on the skin.

Answer False. Transient pathogens are picked up during contamination.

Chain of Infection An infectious agent A reservoir for growth and reproduction An exit route from the reservoir A means of transmission A portal of entry A susceptible host

Chain of Infection (cont’d)

Biologic Defense Mechanisms Anatomic or physiologic methods that stop microorganisms from causing an infectious disorder Mechanical: physical barriers that prevent microorganisms from entering the body or expel them before they multiply Chemical: destroy or incapacitate microorganisms through natural biologic substances

Healthcare- Associated Infections Healthcare-associated infections are infections acquired while a person is receiving care in a health care agency

Question Is the following statement true or false? Mechanical defense mechanisms destroy or incapacitate microorganisms through natural biologic substances.

Answer False. Chemical defense mechanisms destroy or incapacitate microorganisms through natural biologic substances.

Asepsis Practices that decrease or eliminate infectious agents, their reservoirs, and vehicles for transmission A major method for controlling infection Health care professionals use medical and surgical asepsis to prevent spread of infections

Medical Asepsis Confines or reduces the numbers of microorganisms Involves measures that interfere with the chain of infection in various ways Examples: Performing hand hygiene Wearing hospital garments

Surgical Asepsis Measures that render supplies and equipment totally free of microorganisms Practices that avoid contaminating microbe- free items Examples: Physical sterilization Chemical sterilization

Principles of Medical Asepsis Microorganisms exist everywhere except on sterilized equipment Frequent hand washing and maintaining intact skin reduces transmission of microorganisms Blood, body fluids, cells, and tissues are major reservoirs of microorganisms Personal protective equipments serve as barriers to microbial transmission

Principles of Medical Asepsis (cont’d) A clean environment reduces microorganisms Cleaning should be done from cleaner to dirtier areas

Question Is the following statement true or false? Surgical asepsis involves measures that interfere with the chain of infection in various ways.

Answer False. Medical asepsis involves measures that interfere with the chain of infection in various ways.

Practicing Hand Antisepsis Apply about a nickel- to quarter-sized volume of the product to the palm of one hand or the amount recommended by the manufacturer Distribute the product to cover all surfaces of the hands and fingers Rub the product between the hands for 15 to 25 seconds until they are dry

Question Which of the following is a method of surgical asepsis? a. Donning a sterile gown b. Using antimicrobial agents c. Performing hand antisepsis d. Performing hand washing

Answer a. Donning a sterile gown Donning a sterile gown is a method of surgical asepsis. Using antimicrobial agents, performing hand antisepsis, and hand washing are methods of medical asepsis.

Types of Hospital Garments Gloves Scrub suits and gowns Masks; Respirators Uniforms Hair and shoe covers Protective eyewear

Utility Rooms Health care agencies: at least 2 utility rooms (clean and dirty); personnel must not place soiled articles in the clean utility room The utility room contains: Covered waste receptacles and laundry hampers Flushable hopper and a sink Equipment for testing stool or urine

Concurrent Disinfection Clean less-soiled areas before grossly dirty ones Wet-mop floors and damp-dust furniture to avoid distributing microorganisms on dust and air currents Frequently discard solutions used for mopping in a flushable hopper Never place clean items on the floor

Terminal Disinfection More thorough than concurrent disinfection and consists of measures used to clean the client environment after discharge Includes scrubbing the mattress and the insides of drawers and bedside stands

Sterilization Consists of physical and chemical techniques that destroy all microorganisms including spores Physical sterilization: radiation, boiling water, free-flowing steam, dry heat, steam under pressure Chemical sterilization: peracetic acid, ethylene oxide gas

Principles of Surgical Asepsis Once equipment and areas are free of microorganisms, they remain in that state if contamination is prevented Sterility preserved: touching one sterile item with another that is sterile Once a sterile item touches something that is not sterile, it is considered contaminated Any partially unwrapped sterile package is considered contaminated

Principles of Surgical Asepsis (cont’d) Question the sterility of an item considered unsterile Longer the time since sterilization, the more likely that the item is no longer sterile Commercially packaged sterile item is not considered sterile past its recommended expiration date Opened sterile item or area, left unattended, is considered contaminated

Principles of Surgical Asepsis (cont’d) Once a sterile item is opened or uncovered, it becomes contaminated The outer 1-inch margin of a sterile area is considered a zone of contamination A wet sterile wrapper wicks microorganisms from its supporting surface, causing contamination

Principles of Surgical Asepsis (cont’d) Coughing, sneezing, or excessive talking over a sterile field causes contamination Reaching across an area that contains sterile equipment may cause contamination Sterile items located or lowered below waist level are considered contaminated

Surgical Asepsis Procedures Donning sterile gloves, gown Creating and maintaining a sterile field Adding items to a sterile field Handling sterile items and solutions