NCLEX-RN: Infection Control

Infection Control: Infection

Focus topic: Infection Control

Infection Control: The Infectious Process

Focus topic: Infection Control


A. For an infection to occur, a process involving six links or steps must be present.

  • If any links are missing, the infection will not occur.
  • Infection control measures can interrupt the process by eliminating one or more of the steps.

B:. Six links form the chain of infection.

  • Infectious agent (microorganism): bacteria, virus, fungi, etc.
    a. Capability of producing an infection depends on
    (1) Virulence and number of organisms present.
    (2) Susceptibility of host.
    (3) Existence of portal of entry.
    (4) Affinity of host to harbor microorganism.
    b. The circumstances above must be present to produce an infection.
  • Reservoir: People, equipment, water, etc., provide survival for organism.
    a. Appropriate environment for growth and multiplication of microorganism must be present.
    b. Reservoirs’ sources include respiratory, gastrointestinal, reproductive, and urinary tracts, and the blood.
  • Portal of exit from reservoir: Allows the microorganism to move from reservoir to host (includes excretions, secretions, skin, droplets).
  • Route of transmission of microorganisms: five routes. Three primary routes (contact, droplet and airborne); two lesser routes (vehicle [contaminated items such as food, water, and devices] and vector [e.g., mosquitoes, fleas, rats]).
    a. Contact—most frequent source of healthcare-associated infection.
    (1) Direct contact—transmission body to body and physical transmission (sexual intercourse, kissing, or touch).
    (2) Indirect contact—contact with contaminated intermediate object (needle, dressing, dirty hands).
    b. Droplet—transmission of large particle droplets (larger than 5 microns); diphtheria, pertussis, pneumonia, etc.
    c. Airborne—transmission of small particle droplets or residue of 5 microns (measles, varicella, tuberculosis [TB]).
    d. Two lesser routes.
    (1) Common vehicle: transmission by contaminated items such as food, water, devices.
    (2) Vector-borne: mosquitoes, fleas, rats, etc.
  • Portal of entry: mucous membrane, gastrointestinal (GI) tract, genitourinary (GU) tract, respiratory tract, and nonintact skin.
  • Susceptible host: A host who is immunosuppressed, fatigued, malnourished, weakened by other diseases, elderly, stressed, or hospitalized with wounds, IVs, and catheters is at high risk.

Infection Control: Barriers to Infection

Focus topic: Infection Control

A. The primary barrier to infection is the individual’s general health and immunologic system (defense mechanisms).
B. Factors that contribute to infection susceptibility.

  • Disease states.
  • Altered nutritional status.
  • Stress and fatigue.
  • Metabolic function.
  • Age.
  • Medications.

C. The body’s protection against infection.

  • The immune process.
    a. Natural immunity is inherited.
    b. Acquired immunity comes from disease exposure or vaccinations.
  • Anatomic barriers (skin and mucous membranes).
    a. Integrity of the skin and mucous membrane—when integrity is broken, bacteria can enter the body.
    b. How quickly a wound heals depends on the degree of vascularization in the injured area.
  • The inflammatory process.
    a. When an area is inflamed, cells activate the plasmin, clotting, and kinin systems to release histamine.
    b. Histamine creates increased vascular permeability at the injured site.
    c. Phagocytes are summoned to the site to combat the infection.

D. Assessing the probability of infection.

  • Considering the numbers of organisms, virulence, and resistance of the host, the client’s risk factors can be evaluated.
  • Combining these variables with the client’s general health and immune status, the probability of healthcare-associated infection can be assessed.

E. Conditions predisposing client to infection.

  • Surgical wounds.
  • Alterations in the respiratory or genitourinary tracts (most common sites for healthcareassociated infections).
  • Invasive devices such as central lines or venipuncture sites.
  • Implanted prosthetic devices—cardiac valves, grafts, shunts, or orthopedic joints or pins.

Infection Control: Centers for Disease Control and Prevention Guidelines

Focus topic: Infection Control

Infection Control: Principles of Precautions

Focus topic: Infection Control

A. Risk reduction.

  • Standard precautions—hand hygiene is primary method.
  • Follow procedures to recognize and reduce risks.
  • Assign infection control practitioner for every 250 beds.
  • Have hospital epidemiologist on site.
  • Program of surveillance for healthcare-associated infections with appropriate interventions.

B. The Centers for Disease Control and Prevention (CDC) guidelines, revised in 1994, contain two tiers of precautions.
C. First-tier standard precautions blend the major features of universal precautions (blood and body fluids precautions) and body substance isolation into a single set of precautions.

  • Used for the care of all clients in hospitals regardless of diagnosis or infection status.
  • Applies to blood, all body fluids, secretions, and excretions, whether or not they contain visible blood; nonintact skin; and mucous membranes.
  • Standard precautions are designed to reduce the risk of transmission of both recognized and unrecognized sources of infection in hospitals.
  • As a result of the new category of standard precautions, clients with diseases or conditions that previously required category-specific or disease-specific precautions are now covered under this category and do not require additional precautions.

D . Second-tier transmission-based precautions are designed only for the care of specified clients. They reduce the disease-specific precautions into three sets of precautions based on routes of transmission.

  • Categories designed for clients documented or suspected to be infected or colonized with highly transmissible or epidemiologically important pathogens for which additional precautions must be used to interrupt transmission to others in the hospital.
  • Three types of transmission-based precautions include airborne precautions, droplet precautions, and contact precautions.
    a. Airborne precautions reduce the risk of airborne transmission of infectious agents, such as measles, varicella, and tuberculosis.
    b. Droplet precautions are used to prevent the transmission of diseases such as meningitis, pneumonia, scarlet fever, diphtheria, rubella, and pertussis.
    c. Contact precautions are used for clients known or suspected to have serious illnesses easily transmitted by direct contact, such as herpes simplex, staphylococcal infections, hepatitis A, respiratory syncytial virus, and wound or skin infections.
  • All three types of precautions may be used at one time when multiple routes of transmission are suspected in a client. These precautions are always used in conjunction with standard precautions.

E. Transmission-based precautions are used (in addition to standard precautions) when a client is infected with microorganisms or communicable disease.

  • Airborne precautions.
    a. Implemented when infections can spread through the air (TB, chickenpox, rubeola).
    b. Pathogens can be suspended in air for long periods and are transmitted when a person inhales particles that contain the pathogen.
    c. Healthcare workers should wear HEPA (high-efficiency particulate air) filter respirators when working with clients who have TB.
  • Droplet precautions.
    a. This system is used when caring for clients
    who have infections that spread by large particle droplets containing microorganisms (includes rubella, diphtheria, mumps, pertussis, influenza).
    b. Clients with this type of infection should be in a private room or with another client with same disease.
    c. Healthcare workers should wear a surgical mask for protection when coming within 3 feet of client.
  • Contact precautions.
    a. These precautions are used when caring for clients infected or colonized by microorganisms that spread by direct contact (skin to skin) or indirect contact (touch) with a contaminated object.
    b. Client requires private room or room with another client with same illness.
    c. Wear gloves and gown when entering room and change gloves as needed during care. Remove gloves and gown and wash hands when leaving client’s room.
    d. Use dedicated equipment when a client has multiple drug resistant microorganisms.

F. Transmission guidelines.

  • Infections and conditions fall into two categories because microorganisms are transmitted in more than one way.
    a. Chickenpox and zoster can spread through both airborne and contact routes.
    b. Adenovirus infection can spread through droplet and contact.
  • If client’s infection spreads through two transmission routes, institute both precautions and hang both signs on client’s door.

G. Transmission-based precautions and client transfer.

  • When client is transferred to another unit or area for testing, client must wear a mask and impervious dressing.
  • Transporter takes necessary precautions and wears appropriate barriers.
  • Staff in receiving area have been notified and understand precautions.

H. Methods of infection prevention.

  • Vaccinations.
    a. Currently more than 25 vaccines licensed in United States.
    b. Preventive vaccines: smallpox, measles, mumps, rubella, polio, diphtheria, pertussis, and tetanus.
    c. Goal of vaccines: to prevent specific infectious diseases in a specific population.
  • Education.

Infection Control: Standard Precautions

Focus topic: Infection Control

A. The term standard precautions incorporates universal blood and body fluid precautions.
B. Apply standard precautions to all clients regardless of diagnosis or infection status.
C. The following guidelines are recommended by the CDC for use with all clients (whether identified as infectious or not) to prevent transmission of infections. Please follow these guidelines when caring for clients.

  • Hand hygiene: Wash hands thoroughly with soap and water or alcohol-based hand rub or gel before and after all client contact. Wash hands and change gloves between contact with clients.
  • Wear gloves if there is a possibility of direct contact with blood or bodily secretions (e.g., pus, sputum, urine, feces, blood, saliva).
    a. This includes a neonate before first bath.
    b. Wash as soon as possible if unanticipated contact with these body substances occurs.
  • Gloves should be worn when in contact with items or surfaces soiled with blood or body fluids.
  • The CDC states that healthcare workers in contact with clients must remove all false fingernails.
  • Protect clothing with gowns or plastic aprons if there is a possibility of being splashed or direct contact with contaminated material.
  • Wear masks and/or goggles or face shields to avoid being splashed, especially during suctioning, irrigations, and deliveries.
  • Do not break needles into receptacles; rather, discard them intact and uncapped into containers.

Infection Control: Healthcare-Associated Infections

Focus topic: Infection Control

Infection Control: Risks of Hospitalization

Focus topic: Infection Control

A. The CDC has replaced the term “nosocomial infections” with healthcare-associated infections (HAIs). The term was revised to reflect changes in healthcare development.
B. Major risk—HAI infections; leading cause of death in United States.

  • More than 75,000 deaths/year as direct or indirect result of infections (CDC, 2014).
  • These infections begin in hospital or healthcare facility—each year more than 700,000 clients in the United States acquire infections in these settings (CDC, 2014).
  • Major source of HAIs: Healthcare workers and clients are reservoirs.
  • One-third of all HAIs could be prevented with effective infection control programs in healthcare facilities.
  • CDC states these figures can be reduced with client education and strict adherence to infection control practices.

C. Most common sites for infection.

  • Urinary tract infections most common (80% related to catheterization).
  • Pneumonia second most common HAI.
    a. Affects 40% of all critically ill or immunocompromised clients.
    b. Causes 15% of all in-hospital deaths.
  • Surgical wound infections account for 60% of additional hospital days.

D. Intravascular devices present increased risk.

  • Risk of infection related to device itself, site of insertion, and technique of insertion.
  • Staphylococcus is usual cause of infection and bacteremia.

Infection Control: Drug-Resistant Strains of Pathogens

Focus topic: Infection Control

A. Major organisms: Clostridium difficile, Staphylococcus aureus (MRSA), and vancomycin-resistant enterococcus (VRE).
B. Vancomycin-resistant enterococcus (VRE) was a serious development in the 1990s.

  • Enterococcus faecium (called a supergerm) frequently invades surgical wounds, heart valve replacements, and abdominal and urinary tracts.
  • Enterococcal infections are often impervious to antibiotics—25% of these infections in intensive care clients were untreatable.
  • The most common is C. difficile, an anaerobic, gram-positive, spore-forming bacillus associated with infectious diarrhea.
  • Methicillin-resistant Staphylococcus aureus (MRSA).
  • Resistant strain of Mycobacterium tuberculosis.

C. A new super antibiotic, called Zyvox, is a new weapon against drug-resistant infections.

  • The first entirely new type of antibiotic in 35 years.
  • Drug should be reserved to fight life-threatening infections that are resistant to other antibiotics.

D. A new multidrug-resistant bacteria (carbapenemresistant Klebsiella pneumoniae or CRKP) is now being found in hospitals.

  • CRKP is now found in 36 states especially in long-term care facilities.
  • This gram-negative bacteria lives in our intestines and is resistant to almost all antibiotics.
  • This organism enters the body through the lungs as ventilator-causing pneumonia, an IV-causing sepsis, or the urinary tract.
  • It is transmitted by person-to-person contact.
  • The only drug that has been found to work is colistin, a toxic antibiotic that can damage the kidneys.
  • Nursing care involves simple strict hygiene to prevent transmission and strict isolation.

Infection Control: Basic Infection Control Measures

Focus topic: Infection Control

A. Hand hygiene.

  • Many nurses believe wearing gloves eliminates the need to wash hands—not so!
    a. Donning gloves with unclean hands can transfer microorganisms to outside of glove. (People carry between 10,000 and 10 million bacteria on each hand.)
    b. It is important to wash hands between client contacts and before and after using gloves.
  • Proper method of washing hands.
    a. Wet hands with warm, not hot, running water.
    b. Apply soap or antimicrobial agent.
    c. Rub hands together vigorously for at least 15 seconds—include all surfaces of fingers and hands.
    d. Rinse hands thoroughly under running water to remove all soap.
    e. Dry hands with paper towels removed one at a time from dispenser.
    f. Use paper towel to turn off faucet if there is no foot pedal.
  • Washing with waterless agents.
    a. Use only if hands are free of obvious dirt.
    b. Apply small amount on palm of hand.
    c. Rub hands together vigorously, covering all surfaces of hands and fingers.
    d. Rub until dry.

B. Gloving: basic infection control measure.

  • The Occupational Safety and Health Administration (OSHA) stipulates that gloves in all sizes are to be available for healthcare workers.
  • Gloves are necessary for any task or procedure that may result in blood or body fluid exposure to hands.
  • Important to change gloves and wash hands between clients.

C. Latex allergy to gloves.

  • Affects 8% to 12% of healthcare workers.
  • Assess allergy to avocados, bananas, kiwi fruit, or chestnuts. Client may have cross-sensitivity to latex.
  • Classified as immediate immunological reaction caused by latex proteins.
  • Reaction may progress to anaphylaxis.
  • Know symptoms of latex allergy: contact dermatitis, local swelling, itching, hives, redness.
  • If healthcare worker thinks he or she has latex allergy, he/she should switch to latex-free gloves immediately.

D. Items needed as protective barriers.

  • Gloves most common barrier protection: Protects health workers from mucous membranes, wounds, or infectious body substances.
  • Face mask: Prevents airborne infection. Change mask every 30 minutes or sooner if it becomes damp.
  • Face shield or goggles: Reduces risk of contamination of mucous membranes of eyes. Wear when there is risk of being sprayed or splashed with contaminated body fluids.
  • Gown: Protects clothing from splashed blood or body fluids.

E. Removing protective garb.

  • Untie ties of gown if tied in front (ties are contaminated).
  • Remove gloves.
    a. Do not touch outer surface to skin.
    b. Pull first glove down, turning inside out as you pull it off.
    c. Insert two fingers of ungloved hand inside glove edge and pull downward.
    d. Discard gloves in dedicated receptacle.
  • Remove gown: Unfasten waist ties (if tied in back), then neck ties. Pull gown off shoulders and over arms, turning gown inside out as it is removed, and discard.
  • Remove face shield or goggles (do not touch face) and discard.
  • Remove mask: Untie lower string first, then upper strings, and discard.
  • Complete procedure by washing hands.

F. Isolation protocol.

  • Prepare for isolation.
    a. Check physician’s orders.
    b. Obtain isolation cart.
    c. Place isolation cart at client’s door.
    d. Place a linen hamper and trash cans conveniently.
  • Follow dressing procedure when entering or leaving room.
    a. Gown or wear plastic apron.
    b. Use a mask (HEPA filter recommended).
    c. Use an eye shield or goggles if appropriate.
  • Remove items from isolation room by double bagging (using red biohazard bags).

G. Governmental regulatory agencies.

  • CDC goal is disease reduction.
  • OSHA goal is to reduce risk exposure.
  • OSHA requires that healthcare facilities have educational protocols in place for prevention of blood-borne pathogens and hepatitis B control.

Infection Control


Infection Control: Healthcare-Associated Infections (Formerly Called Nosocomial Infections)

Focus topic: Infection Control

Definition: Infections acquired while the client is in the hospital or healthcare facility—infections that were not present or were incubating at the time of admission.

A. Affect more than 2 million and estimated to cause or contribute to more than 99,000 deaths annually in the United States.
B. Many of these infections are caused by pathogens transmitted from one client to another by healthcare workers.
C. Usually caused by poor or no hand hygiene technique between clients.

Infectious Diarrhea

Focus topic: Infection Control

A. Most common cause is Clostridium difficile
associated diarrhea (CDAD) infectious diarrhea.

  • Anaerobic, gram-positive bacillus—20% to 40% of hospitalized clients become colonized within a few days of entering hospital.
  • Spores and microbes found on hospital toilets, bedpans, floors, and healthcare workers’ hands.

B. Recognizing signs and symptoms of CDAD.

  • Diarrhea occurring after antibiotics.
  • Abdominal pain—crampy pain and abdominal tenderness.
  • Fever—above 102.2°F (39°C).
  •  as high as 50,000/mm3 (average is 4500 to 11,000).
  • Lab tests will confirm CDAD with a positive stool assay for toxin A or B and autotoxin neutralization test.

C. Preventive methods.

  • Wash hands before and after client contact and after removing gloves with antiseptic soap. Alert: The alcohol-based gels do not kill C. difficile, so soap and water must be used.
  • In addition to standard precautions, institute contact isolation precautions—includes placing client in a private room and always wearing gloves and gown when in direct contact with client.
  • After removing gloves and gown, do not touch any potentially contaminated surface.
  • Use dedicated equipment such as stethoscope and blood pressure (BP) cuff—never use electronic thermometer because of the potential for spreading bacteria.
  • Dispose of all contaminated items (bed linens, towel) in proper receptacles.
  • Instruct family and friends to use infection precautions.

D. Treatment.

  • Antibiotics for a mild case.
  • For more severe cases, the physician may discontinue the antibiotic and start antimicrobial therapy (metronidazole drug of choice).
  • CDC has recently advised against using vancomycin to treat CDAD because of vancomycinresistant enterococcus (VRE).

Infection Control: Pneumonia

Focus topic: Infection Control

A. Second most common infection—affects 40% of all critically ill or immunosuppressed clients.

  • Aspiration of gram-negative bacteria are typically acquired in the hospital.
  • Gram-positive strain (Staphylococcus aureus) is leading cause of condition; develops into methicillin-resistant condition (MRSA).
    a. Vancomycin, drug of choice to treat MRSA, is rapidly losing its effectiveness.
    b. MRSA may occur when food, fluid, or gastric contents enter lung via aspiration.
    c. MRSA may also occur when airborne particles are inhaled through respirations or anesthesia equipment.
  • Viral pneumonia (causes 20% of all HAIs). Most common are adenoviruses, influenza, and respiratory syncytial viruses (RSV).
  • Fungal pneumonia Aspergillus through contact with unfiltered air system, food, or plants.

B. Preventive measures.

  • Change ventilator tubing no more frequently than every 48 hours.
  • Use closed suction system.
  • Remove pooled secretions above cuff when endotracheal (ET) tube is repositioned.
  • Provide frequent mouth care.
  • Provide 100% relative humidity at body temperature with all ventilation systems (will help client fight off pneumonia infection).
  • Recognizing signs and symptoms.
    a. Onset 72 hours after hospital admission.
    b. Crackles in lung and dullness on percussion.
    c. Purulent sputum.
    d. Positive bacterial or fungal culture.
    e. In elderly client, may be confusion and fatigue with no fever.

C. Treatment.

  • Administer antibiotics as prescribed.
  • Observe for dyspnea, respiratory rate, and administer O2 (as prescribed) to maintain PaO2 at 80 mm Hg plus.
  • Position client at 45-degree angle.
  • Encourage fluid intake—good nutrition.
  • Encourage incentive spirometry.

Infection Control: Bloodstream Infections

Focus topic: Infection Control

A. Types of infection.

  • Presence of bacteria in bloodstream.
  • Fungemia—infection in bloodstream caused by a fungal organism.

B. Two categories of infection.

  • Primary infection means host has no preexisting infection but there is direct introduction of microorganisms into bloodstream and host becomes infected via external (catheter) or internal means (internal tubing during manipulation).
  • Secondary infection occurs when host has another site of infection (urinary tract) that enters bloodstream.

C. Preventive measures.

  • IV therapy increases risk of invasion by harmful microorganisms (invasive devices and venipuncture sites provide route for infection to occur).
  • Use of impeccable standard precaution methods will reduce risk.

Infection Control: Tuberculosis

Focus topic: Infection Control

A. Tuberculosis is an infectious disease caused by the
tubercle bacillus Mycobacterium tuberculosis.

  • Currently 100 million afflicted—30 to 40 million will die and one-third may be resistant.
  • Main reservoir for the organism is respiratory tract.
  • Transmission occurs between individuals through respiratory contact via droplets transmitted through productive coughing.

B. Symptoms.

  • Occur 4–12 weeks after exposure.
  • Active disease and symptoms of cough, weight loss, and fever usually occur within first 2 years after infection.
  • Latent infections (asymptomatic) are not infectious and may last a lifetime.
  • Without treatment, tuberculosis progresses.

C. Multidrug-resistant tuberculosis (MDR-TB).

  • Disease can progress from diagnosis to death in 4–15 weeks.
  • Clients develop resistance to standard drug regimen as a result of noncompliance and/or inappropriate drug therapy.
  • MDR-TB also caused by person-to-person contact through sneezing or coughing, or from a person with primary drug resistance.
  • According to the CDC, MDR-TB accounts for 1.2% of TB cases.

D. Effective tuberculosis control requirements: early identification, isolation, and treatment of persons with active tuberculosis.

  • Purified protein derivative (PPD) skin test used to quickly identify infection in the absence of clinical symptoms.
  • Sputum specimens for acid-fast bacilli (AFB), culture, sensitivity, and chest x-rays.
    a. PPD skin test is read 48–72 hours after the injection.
    b. Positive skin test is indicated by an induration of 10 mm or more at site of injection.
    c. HIV or immunosuppressed—5 mm or more is considered positive. If positive, chest x-ray will rule out active TB.
  • CDC recommendation for tuberculosis isolation—directional airflow, negative pressure ventilation system in room.
    a. Anyone entering the client’s room should wear a mask that forms a tight-fitting seal against particulates 1–5 μ.
    b. Disposable particulate respirators are suggested by the CDC when adequate ventilation is not available in the room.

Infection Control: Infected Wounds

Focus topic: Infection Control

A. The longer a person is hospitalized prior to the surgical procedure, the greater risk of post-surgical infection.
B. Factors that influence infection rates.

  • Duration of time in the operating room.
  • Time surgery is done (between midnight and 8 am is period of greatest risk).
  • Whether client has post-surgical drains in place.
  • If the surgery enters a colonized or infected part of the body.









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