Asepsis and infection control Page

1. Asepsis and infection controlPage Shurouq Qadose 20/9/2010

2. Nurses are directly involved in providing a biologically safe environment. Microorganisms exist everywhere: in water, in soil, and on body surface such as the skin, intestinal tract, and other areas open to the outside (e.g., mouth, upper respiratory tract, vagina, and lower urinary tract). Most Microorganisms are harmless, and some are even beneficial in that they perform essential functions in the body. Some Microorganisms found in the intestines (e.g., enterobacteria) produce substance called bacteriocins, which are lethal to related strains of bacteria. Some Microorganisms are normal resident flora in one part of the body, yet produce infection in another.

3. For example. Escherichia coli is a normal inhabitant of the large intestine but a common cause of infection of the urinary tract. Infection is an invasion of body tissue by microorganisms and their growth there. Such a microorganism is called an infectious agents. If the microorganism produces no clinical evidence of disease, the infection is called asymptomatic or subclinical. A detectable alteration in normal tissue function, however, is called disease.

4. M.O vary in their virulence (i.e., their ability to produce disease). M.O also vary in the severity of the diseases they produce and their degree of communicability. If the infectious agent can be transmitted to an individual by direct or indirect contact or as airborne infection, the resulting condition is called a communicable disease. Pathogenicity is the ability to produce disease, thus a pathogen is a M.O that causes disease.

5. Asepsis: is the freedom from disease –causing microorganisms. To decrease the possibility of transferring M.O from one place to another , aseptic technique is used. There are two basic types of asepsis: medical and surgical. Medical asepsis includes all practices intended to confine a specific M.O to a specific area, limiting the number, growth, and transmission of M.O. In medical asepsis, objects are referred to as clean or dirty. Surgical asepsis refers to ‘’ sterile technique ‘’ refers to those practices that keep an area or object free of all microorganisms; it includes practices that destroy all microorganisms and spores.

6. Surgical asepsis is used for all procedures involving the sterile areas of the body. Sepsis is the state of infection and can take many forms, including septic shock.

7. Types of Microorganisms Four major categories of microorganisms cause infection in humans: bacteria, viruses, fungi, and parasites. Types of infections Infections can be:- localinfection is limited to the specific part of the body where the microorganisms remain. Systemicinfection when microorganisms spread and damage different parts of the body.

8. When a culture of the person’s reveals M.O, the condition is called bacteremia. When bacteremia results in systemic infection, it is referred to as septicemia. There are also acute or chronic infections. Acute infections generally appear suddenly or last a short time. A chronic infection may occur slowly, over a very long period, and may last months or years.

9. Nosocomial Infections Refers to ‘’ hospital – acquired’’ infection are classified as infections that are associated with the delivery of health care services in a health care facility. Nosocomial infection can either develop during a client’s stay in a facility or manifest after discharge. The most common settings where nosocomial infections develop are hospital surgical or medical intensive care units. The most common nosocomial infection sites are UT, RT, bloodstream, and wounds.

10. The microorganisms that cause Nosocomial infections can originate from the client themselves (an endogenous source) or from the hospital environment and hospital personnel (exogenous source). Most nosocomial infections appear to have endogenous sources.

11. A number of factors that contribute to nosocomial infections. Iatrogenic infection are the direct result of diagnostic or therapeutic procedures. e.g., bacteremia that result from an intravascular line. Compromised host, that is a client whose normal defenses have been lowered by surgery or illness. The hands of personnel are a common vehicle for the spread of M.O. Nosocomial infections extend hospitalization time, ↑ client’s time away from work, cause disability and discomfort, and even result in loss of life.

12. Chain of Infection

13. Six links make up the chain of infection:- 1- Etiologic agent The first link in the chain of infections is the microbial agent, which may be bacterium, virus, fungus, or parasite. The ability of the infectious agent to cause disease depends on its:- Pathogenicity……. Is the organism’s ability to harm and to cause disease. Virulence ………. Relates to the vigor with which the organism’s can grow and multiply. Invasiveness ……….. Describes the organism’s ability to enter tissues. Specificity ………… Refers to the organism’s attraction to a specific host, which may include humans.

14. 2- Reservoir or source Common sources are other humans, the client’s own M.O, plants, animals, or the general environment. A carrier is a person or animal reservoir of a specific infectious agent that usually does not manifest any clinical signs of disease. Food, water, and feces also can be reservoirs.

15. 3- Portal of exit from reservoir Before an infection can establish itself in a host, the M.O must leave the reservoir. See the table 31-3

16. 4- Method of Transmission Refers to the way in which the organism moves or is carried from the source’s portal of exit. There are three mechanisms:- • Direct transmission • Indirect transmission May be either vehicle – borne or vector – borne. • Vehicle – borne transmission A vehicle is any substance that serves as an intermediate means to transport and introduce an infectious agent into a susceptible host through a suitable portal of entry.

17. b. Vector – borne transmission A vector is an animal or flying or crawling insect that serves as an intermediate means of transporting the infectious agent. 3. Airborne transmission Airborne transmission may involve droplets or dust.

18. 5- Portal of entry to the susceptible host Pathogens can enter susceptible hosts through body orifices, such as the mouth, nose, ears, eyes, vagina, rectum or urethra, breaks in the skin. 6- Susceptible Host Is any person who is at risk for infection. A compromised host is a person at increased risk, an individual who for one or more reasons is more likely than others to acquire an infection. Impairment of the body’s natural defenses and a number of other factors can affect susceptibility to infection.

19. Factors increasing susceptibility to infection One of the most important factors is host susceptibility, which is affected by:- • Age • Heredity • Nutritional status • Current medical therapy • Preexisting disease processes Susceptibility is the degree to which an individual can be affected or the likelihood of an organism causing an infection in that person.

20. Nursing Management Assessing • Nursing History • Physical Assessment • Laboratory Data Diagnosing Planning Implementing • Preventing Nosocomial infections Many nosocomial infections can be prevented using proper hand hygiene techniques, environmental controls, sterile techniques.

21. Hand Hygiene Nothing is more effective than hand hygiene to prevent the spread of infection. It is also the least expensive method for decreasing the risk of infecting oneself or others. Contact transmission, from the hands of healthcare personnel or the clients themselves, is the most common form of contamination because microorganisms are transient flora until the hands are washed.

24. Factors that contribute to poor compliance with hand washing :- - Lack of awareness of client care activities that require handwashing, such as taking blood pressure or shaking hands with a client. - Common misperception that wearing gloves and gowns can substitute for handwashing - Understaffing and high workloads. - Inaccessibility of sinks - Skin irritation and dryness

25. Wash your hand in the following situations: • At the beginning and end of the shift • Before the contact with a client • Between contacts with different clients • Before and after contact with wounds, dressing, specimens • Before performing any invasive procedure • Before administering medications • After contact with client secretion • Before and after using the bathroom • After sneezing, coughing, or blowing your nose • After removing gloves • Before eating

26. The CDC” Center for Disease Control and Prevention” recommends antimicrobial hand washing agents in the following situations: • When there are known multiple resistant bacteria. • Before invasive procedures • In special care units, such as nurseries and ICUs • Before caring for severely immuno compromised clients.

27. Medical and surgical asepsis vary in the technique for proper handwashing. Handwashing for surgical asepsis usually takes longer. Most long – term flora on the hands reside in the nailbed and under the fingernails, so keep fingernails short and avoid nail polish. Remove all rings before handwashing to minimize the potential places for bacteria.

28. The hands are washed each time gloves are removed for two primary reasons: (a) the gloves may have imperfections or be damaged during the wearing so that they could allow microorganism’s entry and (b) the hands may become contaminated during glove removal. Gloves should be changed and discarded between clients or when they become torn or grossly soiled. Gloves should not be washed and reused.

29. Hand washing

31. Supporting Defenses of a susceptible host • Hygiene Intact skin and mucous membranes are one barrier against microorganisms entering the body. Also good oral care, bathing, shampooing all these measure can reduce the presence of microorganisms • Nutrition Adequate nutrition enables tissues to maintain and rebuild themselves and helps keep the immune functioning well.

32. Fluid Fluid intake permits fluid output that flushes out the bladder and urethra, removing microorganism that could cause an infection. • Sleep Adequate rest and sleep are essential to health and to renewing energy.

33. Stress Excessive stress predispose people to infections. Nurses can assist clients to learn stress – reducing techniques • Immunizations The use of immunizations has dramatically decreased the incidence of infectious diseases.

34. Disinfecting and Sterilizing The first links in the chain of infection, the etiologic agent and the reservoir, are interrupted by the use of antiseptics (agents that inhibit the growth of some microorganisms) and disinfectants (agents that destroy pathogens other than spores).

37. Disinfecting A disinfectant is a chemical preparation, such as phenol or iodine compounds, used on inanimate objects. Disinfectants are frequently caustic and toxic to tissues. An antiseptic is a chemical preparation used on skin or tissue. Both antiseptic and disinfectants are said to have bactericidal or bacteriostatic properties. A bactericidal preparation destroy bacteria, whereas bacteriostatic preparation prevents the growth and reproduction of some bacteria. Disinfectants and antiseptics often have similar chemical components, but the disinfectant is a more concentrated solution.

38. When disinfecting articles, nurses need to follow agency protocol and consider the following: • The type and number of infectious organisms. Some microorganisms are readily destroyed, whereas others require longer contact with the disinfectant. • The recommended concentration of the disinfectant and the duration of contact. • The presence of soap. Some disinfectants are ineffective in the presence of soap or detergents. • The presence of organic materials. The presence of saliva, blood, pus, or excretions can readily inactivate many disinfectants. • The surface areas to be treated. The disinfecting agents must come into contact with all surfaces and areas.

39. Sterilizing Sterilization is a process that destroys all microorganisms, including spores and viruses. Four commonly used methods of sterilization are: 1. Moist heat Steam under pressure is used (autoclave) • Gas Ethylene oxide gas destroys M.O by interfering with their metabolic processes. It is also effective against spores. Advantages: good penetration and effectiveness for heat sensitive items. Disadvantage : toxicity to humans

40. 3.Boiling water Most practical and inexpensive method for sterilizing in the home Disadvantage: spores and some viruses are not killed by this method. 4. Radiation Both ionizing (alpha, beta, and x – rays), nonionizing ( ultraviolet light) radiation are used for disinfection and sterilization. Ionizing radiation is used effectively in industry to sterilize foods, drugs, and other items that are sensitive to heat. Advantages: effective for items difficult to sterilize Disadvantage: equipment is very expensive.

41. Steam sterilization

44. Isolation Precautions Isolation refers to measures used to prevent the spread of infections or potentially infectious microorganism to health personnel, clients, and visitors. Category – specific isolation precautionsuse seven categories: strict isolation, contact isolation, respiratory isolation, tuberculosis isolation, enteric precautions, drainage/ secretions precautions, and blood/ body fluid precautions.

45. Disease – specific isolation precautions provide precautions for specific diseases. By use of private rooms with special ventilation, share room with other clients infected with the same organism, use gown. UP are techniques to be used with all clients to ↓ the risk of transmitting unidentified pathogens. UP obstruct the spread of bloodborne pathogens, those M.O carried in blood and body fluids , e.g., HBV,HCV,HIV . Body substance includes blood, some body fluids, urine, feces, wound drainage, oral secretions, and any other body product or tissue.

46. CDC (HICPAC) Isolation Precautions The HICPAC of the CDC introduced new guidelines for isolation precautions in hospitals. These guidelines designate two tiers of precautions:- 1- Standard precautions These used in the care of all hospitalized persons regardless of their diagnosis or possible infection status. They apply to blood, all body fluids, secretions, and excretions except sweat, nonintact skin, and mucous membranes. Table 31-1 page 689

47. 2-Transmission - based precautions These precautions are used in addition to Standard precautions for clients with known or suspected infections that are spread in one of three ways: by airborne or droplet transmission, or by contact. The three types of Transmission- based precautions may be used alone or in combination but always in addition to Standard precautions.

48. a- Airborne Precautions are used for clients known to have or suspected of having serious illness transmitted by airborne droplet nuclei smaller than 5 microns. Examples of such illnesses include measles and tuberculosis. b- Droplet Precautions are used for clients known or suspected to have serious illnesses transmitted by particle droplets larger than 5 microns. Examples of such illnesses are diphtheria, pertussis, mumps, and pneumonia.

49. c- Contact Precautions are used for clients known or suspected to have serious illnesses easily transmitted by direct client contact or by contact with items in the client’s environment. Example of such illnesses includes gastrointestinal, urinary, respiratory, skin or wound infections. Some diseases require a combination of transmission – based precautions. For clients infected with the coronavirus that causes severe acute respiratory syndrome, standard ( including eye protection), contact, and airborne precautions are indicated.

50. Compromised clients Those highly susceptible to infection are often infected by their own M.O ,by M.O on the inadequately cleansed hands of health care personnel, and by nonsterile items (food, water, air, and client care equipment). Clients include those who:- - Have diseases, such as leukemia - Have extensive skin impairments, such as dermatitis or major burns, which cannot be effectively covered with dressings.