infection control .pdf

Infection Control Definitions: Infection: It is a condition that results when microorganisms cause injury to a host. Colonization: A condition in which microorganisms are present, but the host does not manifest any signs or symptoms of infection. Regard...

Infection Control Definitions: Infection: It is a condition that results when microorganisms cause injury to a host. Colonization: A condition in which microorganisms are present, but the host does not manifest any signs or symptoms of infection. Regardless of whether the host is infected or colonized, the host can transmit pathogens and infectious diseases to others. Asepsis: Refers to practices that minimize or eliminate pathogenic organisms. Contamination: The soiling of inanimate objects with potentially infectious substances. Decontamination: A process that removes contamination and therefore prevents microorganisms reaching a susceptible site in sufficient quantities to cause infection. Cleaning: A process that physically removes contamination but does not necessarily destroy microorganisms. Germs/ Microorganisms: Living animals or plants visible only with a microscope. Defenses against infection: natural and acquired: Primary defenses: 1. Skin: ✓ Intact skin protects the body from microbes that would cause disease in subcutaneous or deeper tissue. ✓ When breaks in the skin occur, such as cuts, scrapes, and burns, the resulting opening is a portal of entry for pathogens. 2. Mucous membranes: These membranes produce sticky mucus that traps invading pathogens. a) In the respiratory tract, the mucus may be coughed up and expectorated or blown out of the nose, taking microorganisms with it. b) In the urinary tract, the urethra secretes mucus to trap pathogens that could enter the body through the urinary meatus. Then, the acidic urine washes the pathogens out of the body. c) In the vagina, mucus traps pathogens, preventing them from migrating into the uterus. 3. Gastrointestinal system: ✓ The mouth provides entry into the gastrointestinal system and contains some bacteria. ✓ Saliva contains enzymes that help remove microorganisms from the pathogens. ✓ If any pathogens make it to the stomach, the strong hydrochloric acid found in digestive juices often kills them. Abdulnasser Al-Qadi 1  ✓ Pathogens that enter the intestines, perhaps through food, meet with bile that breaks down and emulsifies fats, as well as killing microbes. Secondary defenses: The second line of defense occurs at the cellular level in reaction to toxins secreted by invading pathogens. a. Inflammatory process: ✓ When an injury occurs, the W cells release histamine and other chemicals, which cause the blood vessels near the injury to dilate. ✓ This dilation results in redness and warmth in the area of injury. ✓ The blood vessels also become more permeable to allow an increased number of white blood cells, or phagocytes, into the injured area. ✓ These phagocytes surround the invading pathogens and consume them. b. Elevated temperature: The increase of body temperature to 101°F or higher is too warm for most invading microorganisms to live and multiply. Tertiary defenses: ✓ The third line of defense involves specialized white blood cells called lymphocytes that fight infection, as either B cells or T cells. ✓ These lymphocytes are found in lymph tissue, such as the spleen, thymus, lymph nodes, and tonsils. Chain of Infection Transmission: Abdulnasser Al-Qadi 2 Infectious agent: - Agent capable of causing disease. - Example: ✓ Bacteria. ✓ Viruses. ✓ Fungi. ✓ Protozoa. Reservoir: - Areservoir, or place the organism grows. - Example: ✓ Humans (patients or healthcare workers) ✓ Animals. ✓ Insects. ✓ Environment (patient care equipment, environmental surfaces and food). Portal of exit: - A portal of exit, or method by which the organism leaves the reservoir. - Example: o Respiratory Tract (coughing, sneezing, talking and suctioning). o Gastrointestinal tract (faces or vomitus). o Skin or mucous membranes (wounds or skin breaks) o Transplacental blood (needle stick or blood transfusion). Mode of transmission: - Method by which the organism reaches a susceptible host. Sach as: - Direct contact: Immediate transmission o Person-to-person. o Actual physical contact between source and patient. - Indirect contact: o Airborne: Organisms contained within droplet nuclei or dust particles (i.e. droplet nuclei of tuberculosis). o Suspended in air for extended periods, may be spread through ventilation systems. o Vector-born: External vector-born transmission; mechanic-altransfer of microbes on external appendages (feet of flies). Abdulnasser Al-Qadi 3 Portal of entry: - A portal of entry, or method by which the organism enters a new host. - Example: - ✓ Respiratory tract. ✓ Genitourinary tract. ✓ Gastrointestinal tract. ✓ Skin/mucous membrane. ✓ Transplacental (fetus from mother) ✓ Parenteral (percutaneous, via blood) Susceptible host: - A susceptible host or person whose body the organism has entered. Factors affecting susceptibility to infections: 1. Inadequate nutrition. 2. Poor hygiene practices. 3. Suppressed immune system. 4. Chronic illness. 5. Insufficient white blood cells. 6. Prematurity. 7. Advanced age. 8. Compromised skin integrity. 9. Weakened cough reflex. 10. Diminished blood circulation. Abdulnasser Al-Qadi 4 Nosocomial infection: Nosocomial infection: Infections acquired while a person is receiving care in a health care agency. Characteristics by: a. Not present at admission. b. >48 hours after admission. c. Acquired in hospital but appear after discharge. d. Occupational infections among staff. Nosocomial infection sources: – Exogenous source: From the hospital environment and hospital personal. – Endogenous source: Nosocomial infections can originate from the clients themselves. Type's nosocomial infection: – Urinary tract infection: 30-40% of cases, indwelling urinary catheter or instrumentation. – Lower respiratory and surgical wound infections: Each about 15%. – Bacteraemia (5%), intravenous site infection, gastrointestinal tract and skin infections. Medical Asepsis Medical asepsis refers to practices performed to prevent the spread of infection. Medical asepsis is commonly referred to as clean technique. The goal is to reduce the number of pathogens or prevent the transmission of pathogens from one person to another. Infection control precautions are physical measures designed to curtail the spread of infectious diseases. Components of standard precautions: A. Hand washing: Simple hand antisepsis: ✓ Hand washing is the single most effective precaution for prevention of infection transmission between patients and staff. ✓ Wash hands for 10 - 15 seconds using soap and water or use antibacterial hand gel unless hands are visibly soiled. ✓ Hand antisepsis is removal & destroys of transient flora using anti-microbial soap or alcohol- based hand rub (for 60 sec.). Abdulnasser Al-Qadi 5  Surgical hand scrub: ✓ Removal or destruction of transient flora and reduction of resident flora using anti-microbial soap or alcohol-based detergent with effective rubbing (for least 2-5 min). ✓ All are performed using a surgical scrub brush and an antimicrobial soap solution. Moments for hand hygiene: 1. Before & after an aseptic technique or invasive procedure. 2. Before & after contact with a patient or caring of a wound or IV line. 3. After contact with body fluids & excreta removal. 4. After handling of contaminated equipment or laundry. 5. Before the administration of medicines 6. After cleaning of spillage. 7. After using the toilet. 8. At the beginning and end of duty. Abdulnasser Al-Qadi 6 Hand washing procedure: B. Isolation: Isolation can be defined as placing patients apart from others or alone. Source isolation: Minimizing the risk of spread of infection between service users by the physical isolation of those service users who pose an infection risk to others: 1. Use strict aseptic technique when performing any invasive procedure (e.g., inserting an intravenous needle or catheter) and when changing surgical dressings. Change intravenous tubing and solution containers according to hospital policy (e.g., every 48 to 72 hours). 2. Check all sterile supplies for expiration date and intact packaging. 3. Prevent urinary infections by maintaining a closed urinary drainage system with a downhill flow of urine. Keep the drainage bag and spout off the floor. 4. Implement measures to prevent impaired skin integrity and to prevent accumulation of secretions in the lungs (for example, encourage the client to move, cough, and breathe deeply at least every 2 hours). Protective isolation: Minimizing the risk of spread of infection between service users by the physical isolation of service users at increased risk of infection. Abdulnasser Al-Qadi 7 C. Personal protective equipment: 1.Gloves: ✓ Disposable gloves must be use when touching blood, body fluids, and secretions, excretions, and contaminated items (i.e., soiled gowns). ✓ Wear for touching patient’s mucous membranes (Examination of oropharynx GIT). ✓ Examining a lacerated or non-intact skin e.g. wound dressing. ✓ Perform proper hand hygiene immediately after removing gloves. ✓ Sterile gloves are used for invasive procedures. ✓ Clean gloves can be unsterile unless their use is intended to prevent the entrance of microorganisms into the body. ✓ Remove gloves before touching non-contaminated items and surfaces. ✓ Perform proper hand hygiene immediately after removing gloves. 2.Masks & protective eyewear: ✓ Must be wear during patient care procedures that could cause splashing of blood, body fluids, or secretions, such as suctioning and endotracheal intubation. ✓ During surgical operations to protect wound from staff breathings. ✓ Masks must be of good quality, properly fixed on mouth and nasal openings. 3.Gowns/Aprons: ✓ Gowns are worn when performing procedures and patient care if there is a possibility of your exposed skin or clothing coming in contact with blood, body fluids, secretions, or excretions e.g. surgical procedures. ✓ The gown is intended to protect clothing. ✓ Remove a soiled gown carefully to avoid the transfer of microorganisms to others (i.e., clients or other health care workers). ✓ Cleanse hands after removing gown. D. Needles and other “Sharps”: ✓ Never recap a used needle. ✓ Do not bend or break needles. ✓ Use safety needles whenever possible. ✓ Place all used sharps in a puncture-resistant sharps container. Abdulnasser Al-Qadi 8 E. Respiratory hygiene/cough: ✓ Cover your mouth and nose with a tissue when sneezing or coughing; if tissue is unavailable, cough into your upper sleeve, not your hand. ✓ Use hand hygiene immediately after coughing or sneezing. ✓ Any person entering a health-care facility with a cough, congestion, or increased respiratory secretions is to follow these recommendations. F. Environmental control: ✓ Including physical facility plans must meet quality and infection control measures. ✓ Patient equipment positioning and installation, traffic flow. ✓ Cleaning of hospital environment and disinfection according to policies. ✓ Proper air ventilation. ✓ Water pipes examination, check its quality. ✓ Proper waste collection and disposal. ✓ Cleaning and dis-infection of equipment. ✓ Proper linen collection, cleaning, distribution. ✓ Food: ensure quality and safety. Surgical Asepsis Defintions: Surgical asepsis means those measures that render supplies and equipment totally free of microorganisms. Surgical asepsis is used in surgery and to sterilize equipment. Sterilization: A process that renders an object free from viable microorganisms, including viruses and bacterial spores. Antiseptics: Inhibit the growth of, but do not kill, microorganisms. An example is alcohol. Antiseptics generally are applied to the skin or mucous membranes. Disinfection: A process that reduces and destroy the number of viable microorganisms but not spores. Phenol, household bleach, and formaldehyde are examples. Antimicrobial: They are chemicals that destroy or suppress the growth of infectious microorganisms. Types of sterilization: 1. Autoclaving: ✓ This method delivers steam under pressure, with heat ranging from 250°F to 270°F, ✓ To sterilize instruments that will not be harmed by heat and water under pressure. Abdulnasser Al-Qadi 9 2. Boiling: ✓ This method of boiling instruments and supplies in water for 10 minutes kills non–spore- forming organisms but does not kill spores. 3. Ionizing radiation: ✓ This method kills pathogens on sutures, some plastics, and biological materials that cannot be boiled or autoclaved. ✓ Exposure to sunlight was used in the past to eliminate microorganisms. 4. Chemical disinfection: ✓ This method is used to kill pathogens on equipment and supplies that cannot be heated. ✓ An example of such a chemical is Cidex, which is used to sterilize rubber-based catheters used in urological procedures. 5. Gaseous disinfection: ✓ This method kills pathogens on supplies and equipment that are heat sensitive or must remain dry. Types of antimicrobial agents TYPE MECHANISM EXAMPLE USE Lowers the surface tension of oil on the 1. Soap skin, which holds microorganisms; Dial, Safeguard Hygiene facilitates removal during rinsing. Sanitizing Acts as soap, except detergents do not Dreft, Tide eating utensils, 2. Detergent form a precipitate when mixed with water. laundry Injures the protein and lipid structures in Isopropanol, Cleansing skin, 3. Alcohol the cellular membrane of some ethanol instruments microorganisms (70% concentration) Damages the cell membrane of microorganisms and disrupts their 4. Iodine enzyme functions; not effective against Betadine Cleansing skin Pseudomonas, a common wound pathogen. Disinfecting Interferes with microbial enzyme Bleach, Clorox 5. Chlorine water, utensils, systems. blood spills Damages the cell membrane of Cleansing skin 6. Chlorhexidine microorganisms, but is ineffective against Hibiclens and equipment spores and most viruses Merthiolate, Disinfecting 7. Mercury Alters microbial cellular proteins Mercurochrome skin Inactivates cellular proteins of bacteria, Sterilizing 8. Glutaraldehyde Cidex viruses, and microbes that form spores equipment Abdulnasser Al-Qadi 10  Type Required Personal Protective Equipment Indications for Use Put on gloves and a gown when To prevent transmission of pathogens spread entering the room; wear gloves when by direct or indirect contact; use in the presence of excessive wound drainage, fecal touching patient's intact skin and the incontinence, and when the patient is apply disinfectant. Contact surfaces and articles in close proximity infected with multiple-drug–resistant Abdulnasser Al-Qadi laundry in coded bags. to the patient, such as side rails and organisms, such as methicillin-resistant Staphylococcus aureus (MRSA), medical equipment. vancomycin-resistant enterococci (VRE), Plus, standard precautions. and Clostridium difficile. Handling of contaminated material: Put on a mask when entering the To prevent transmission of pathogens spread room. Note: If the patient has H1N1 through close contact with respiratory Droplet flu, an N95 respirator is required. secretions or mucous membranes. Examples Instruct patient to follow respiratory include influenza (flu), group A reptococcus, hygiene/cough etiquette. bacterial meningitis, rubella (German Plus, standard precautions measles), and Mycoplasma pneumonia Transmission-based precautions: Put on a fit-tested N95 or higher To prevent transmission of pathogens small respirator when entering the room. enough to be suspended in the air and spread 2. Cleaning & decontamination of equipment: Protective barriers must be worn. Airborne Patient must be placed in an airborne through air currents. Examples include infection solation room with negative tuberculosis, rubeola (measles), chickenpox, pressure. and severe acute respiratory syndrome Plus, standard precautions. (SARS). 3. Handling & processing lab specimens: Must be in strong plastic bags with biohazard label 11 1. Cleaning of body and body fluid spills: wear gloves, wipe-up the spill with paper or towel and 4. Handling and processing linen: soiled linen must be handled with barrier precautions, sent to  5. Handling and processing infectious waste: must be placed in color coded, leakage proof bags, collected with barrier precautions. 6. Contaminated waste incinerated or better autoclaved prior to disposal in a landfill. Decontamination of the equipment: ✓ Equipment must be dried thoroughly after cleaning. ✓ Semi-critical/critical (intermediate and high-risk) equipment such as reusable invasive medical devices (surgical instruments) and endoscopes require decontamination by disinfection and sterilization. ✓ In or damage to the outer packaging, which would render the device unsuitable for use until reprocessed. ✓ Equipment should be in a good state of repair and non-porous to facilitate decontamination. ✓ Equipment must be cleaned by a designated person in a standardized manner after each patient use. ✓ Equipment must always be cleaned prior to maintenance and should be tagged with a decontamination certificate specifying this. Decontamination of the unit: ✓ The unit should be free of clutter to facilitate cleaning. ✓ The unit should be cleaned with a neutral detergent and water except in circumstances that require additional disinfection, for example spillages of blood and body fluid. ✓ Frequency of cleaning is dependent on the patient’s level of hygiene and the degree of unit contamination. ✓ Surfaces that are in close proximity to the patient, such as patient care equipment, commodes, should be cleaned routinely. ✓ Disinfection should be carried out when required using a product that has microbial activity against the infectious agent likely to contaminate the patient care environment, for example hypochlorite 1000 ppm parts per million or 1:10 dilution, following the manufacturer’s instructions. Types of hospital west: 1. Isolation wastes: Wastes generated by hospitalized patients who are isolated to protect others from communicable diseases. 2. Cultures and stocks of infectious agents and associated biological: This category includes: a. Specimens from medical and biological laboratories. b. Cultures and stocks of infectious agents from clinical, research, and industrial laboratories. 3. Human blood and blood products: This includes waste blood, serum, plasma, and blood products. Abdulnasser Al-Qadi 12 4. Pathological waste: Tissues, organs, body parts, blood, and body fluids. 5. Contaminated sharps: Contaminated hypodermic needles, syringes, scalpel blades, Pasteur pipettes, and broken glass. 6. Contaminated animal carcasses, body parts, and animal bedding. Hazards associated with hospital waste: 1. Sources for infectious diseases. 2. Risk for injuries due to sharp subjects like needles, blades. 3. Source for hospital acquired infection. Segregation: separation of healthcare waste from non-health care waste at or near the point of generation. Maintaining the separation during storage, transport, until treatment. Outside the hospital: Biomedical west shall be transported only in vehicles authorized by competent authority as specified by government. Transportation: ✓ Avoidance of mechanical loading devices that may rupture packaged wastes. ✓ Frequent disinfection of carts used to transfer wastes within the facility. ✓ Placement of all infectious waste into rigid or semi-rigid containers before transport off site. ✓ Transport of infectious waste in closed leak-proof trucks or dumpsters. ✓ Use of appropriate hazard symbols in accordance with local, state and federal regulations. ✓ Trolleys should not have any sharp edges and should be easy to clean. Color of bin Waste Treatment Infectious waste Swabs, Gauze, Bandages, Linen, Incineration Yellow bin Body parts, Discarded Medicines. Infected plastics Autoclaving & recycling Red bin Catheters, tubing's, IV bottles, Gloves, Blood Bags. Needles with or without syringes, scalpels, blades. Autoclaving & recycling White bin to foundries Broken glass, vials & ampoules. Autoclaving and Blue bin recycling Green bin Food waste, Fruit peels/seeds with no polythenes Composting Disposal: ✓ Some liquid medical wastes, such as human blood, may be disposed of in sinks if the waste is first autoclaved or brought to a final concentration of 1 percent bleach. ✓ The following medical wastes may not be drain disposed: Abdulnasser Al-Qadi 13  o Human or animal cultures suspected of containing infectious agents, cultures and stocks of infectious agents and wastes from the production of infectious bacteria, viruses, spores, discarded live and attenuated vaccines. Abdulnasser Al-Qadi 14