Chapter 27 Asepsis and Infection Control

1. Chapter 27Asepsis and Infection Control

2. Components of the Infection Cycle • Infectious agent—bacteria, viruses, fungi • Reservoir—natural habitat of the organism • Portal of exit—point of escape for the organism • Means of transmission—direct contact, indirect contact, airborne route • Portal of entry—point at which organisms enter a new host • Susceptible host—must overcome resistance mounted by host’s defenses

3. The Infection Cycle

4. Infectious Agents • Bacteria—most significant and most prevalent in hospital settings • Virus—smallest of all microorganisms • Fungi—plantlike organisms present in air, soil, and water

5. Classification of Bacteria • Spherical (cocci), rod shaped (bacilli), corkscrew shaped (spirochetes) • Gram positive or gram negative—based on reaction to Gram stain • Aerobic or anaerobic—based on need for oxygen

6. Factors Affecting an Organism’s Potential to Produce Disease • Number of organisms • Virulence • Competence of person’s immune system • Length and intimacy of contact between person and microorganism

7. Possible Reservoirs for Microorganisms • Other humans • Animals • Soil • Food, water, milk • Inanimate objects

8. Common Portals of Exit • Respiratory • Gastrointestinal • Genitourinary tracts • Breaks in skin • Blood and tissue

9. Laboratory Data Indicating Infection • Elevated white blood cell count—normal is 5000 to 10,000/mm3 • Increase in specific types of white blood cells • Elevated erythrocyte sedimentation rate • Presence of pathogen in urine, blood, sputum, or draining cultures

10. Aseptic Technique • Includes all activities to prevent or break the chain of infection • Two categories • Medial asepsis—clean technique • Surgical asepsis—sterile technique

11. Factors Predisposing Patients to Nosocomial Infections • Use of invasive medical devices • Antibiotic-resistant organisms developed in hospitals

12. Measures to Reduce Incidence of Nosocomial Infections • Constant surveillance by infection-control committees and nurse epidemiologists • Written infection-prevention practices for all agency personnel • Hand hygiene recommendations • Infection control precaution techniques • Keeping patient in best possible physical condition

13. Bacterial Flora • Transient—attached loosely on skin, removed with relative ease • Resident—found in creases in skin, requires friction with brush to remove

14. Stages of Infection • Incubation period—organisms growing and multiplying • Prodromal stage—person is most infectious, vague and nonspecific signs of disease • Full stage of illness—presence of specific signs and symptoms of disease • Convalescent period—recovery from the infection

15. Factors Affecting Host Susceptibility • Intact skin and mucous membranes • Normal pH levels • Body’s white blood cells • Age, sex, race, hereditary factors • Immunization, natural or acquired • Fatigue, climate, nutritional and general health status • Stress • Use of invasive or indwelling medical devises

16. Body’s Defense Against Infection • Body’s normal flora • Inflammatory response • Immune response

17. Factors Determining Use of Sterilization and Disinfection Methods • Nature of organisms present • Number of organisms present • Type of equipment • Intended use of equipment • Available means for sterilization and disinfection • Time

18. Personal Protective Equipment and Supplies • Gloves • Gowns • Masks • Protective eye gear

19. Evolution of Specialized Infection Control Precautions • Early CDC guidelines • Specific isolation techniques • Disease-specific isolation • Universal precautions • OSHA regulations for universal precautions • Body substance precautions • Current CDC guidelines

20. Current CDC Guidelines • Standard precautions—used in care of all hospitalized patients • Apply to blood, body fluids, secretions, excretions, non-intact skin, mucous membranes • Transmission-based precautions—used in addition to standard precautions for patients with suspected infection • Include airborne, droplet, or contact precautions

21. Type N95 Particulate Respirator

22. Use of Surgical Asepsis • Operating room, labor and delivery areas • Certain diagnostic testing areas • Patient bedside • e.g., for procedures that involve insertion of urinary catheter, sterile dressing changes, or preparing and injecting medicine

23. Patient Teaching for Medical Asepsis at Home • Wash hands before preparing or eating food • Prepare foods at high enough temperatures • Use care with cutting boards and utensils • Keep food refrigerated • Wash raw fruits and vegetables • Use pasteurized milk and fruit juices • Wash hands after using bathroom • Use individual care items

24. Evaluating Patient Goals • Use techniques of medical asepsis • Identify health habits and lifestyle patterns promoting health • State signs and symptoms of an infection • Identify unsafe situations in the home environment

25. Question Which of the following is the most significant and commonly found infection-causing agent in healthcare institutions? A. Bacteria B. Fungi C. Viruses D. Mold

26. Answer Answer: A. Bacteria Rationale: Bacteria are the most significant infection-causing agents in the healthcare system. Bacteria can be categorized by shape, by their reaction to the Gram stain, or according to their need for oxygen. Fungi (molds and yeasts) can cause infection and are present in the air, soil, and water. Viruses cause infections including the common cold, and do not respond to antibiotics.

27. Question Which one of the following infections or diseases may be spread by touching a contaminated inanimate article? A. Rabies B. Giardia C. E. coli D. Influenza

28. Answer Answer: D. Influenza Rationale: Influenza may be spread if a person touches a contaminated article and then touches his eyes or nose. The reservoir for rabies is animals; for Giardia, water; and for E. coli, water or food.

29. Question In which of the following stages of infection is the patient most contagious? A. Incubation period B. Prodromal stage C. Full stage of illness D. Convalescent period

30. Answer Answer: B. Prodromal stage Rationale: The patient is most infectious during the prodromal stage when early signs and symptoms of the disease are present but are often vague and nonspecific. During this stage, the patient often does not realize he or she is contagious and spreads the infection.

31. Question Tell whether the following statement is true or false. Soaps and detergents (nonantimicrobial agents) are considered adequate for routine mechanical cleansing of the hands and removal of most transient microorganisms. A. True B. False

32. Answer Answer: A. True Soaps and detergents (nonantimicrobial agents) are considered adequate for routine mechanical cleansing of the hands and removal of most transient microorganisms.

33. Question Tell whether the following statement is true or false. Standard precautions should be used when caring for a noninfectious, post-operative patient who is vomiting blood. A. True B. False

34. Answer Answer: A. True Standard precautions should be used when caring for a noninfectious, post-operative patient who is vomiting blood.