Infection combined Exam 2 NURN 153

What is infection according to the CCBC concept definition?

The invasion and multiplication of microorganisms in body tissues, which may cause cellular injury or destruction.

What is infection control according to the CCBC concept definition?

Activities used to minimize the spread of microorganisms that cause disease. Examples include handwashing, sanitation, isolation, and sterile procedures.

What is a healthcare-associated infection (HAI)?

An infection associated with receiving healthcare. Risk increases with invasive devices/procedures, longer hospitalization, critical illness, emergency surgery, excessive broad-spectrum antibiotic use, and decreased aseptic technique.

What is an iatrogenic infection?

An infection resulting from a diagnostic or therapeutic procedure. Example: developing a UTI after Foley catheter insertion.

A hospitalized patient develops a UTI after placement of a Foley catheter. What type of infection is this?

An iatrogenic infection because it developed as a result of a therapeutic procedure.

Does exposure to a pathogen automatically mean a patient will develop an infection?

No. Infection requires an intact chain of infection. Breaking any link can help prevent infection.

What are the 6 links in the chain of infection in order?

Infectious agent, Reservoir, Portal of exit, Route of transmission, Portal of entry, Susceptible host

What is the infectious-agent link of the chain?

The microorganism capable of causing disease, such as bacteria, viruses, fungi, protozoa, parasites, prions, or other infectious organisms.

What factors determine whether an infectious agent can produce disease?

Sufficient number of organisms, Virulence, Ability to enter and survive in the host, Host susceptibility

What is the reservoir in the chain of infection?

The place where infectious microbes live or reside, commonly humans but also animals, the environment, or objects/fomites.

What is a carrier host?

A person or animal who has a pathogen and can transmit it to others without showing signs or symptoms of illness.

What environmental conditions help microorganisms thrive?

Food, appropriate oxygen conditions, moisture, warmth, darkness, and favorable pH.

What is a portal of exit?

The route by which an organism leaves its reservoir, such as the respiratory, GI, GU, skin, blood, or tissue routes.

What is the route of transmission?

The method by which a pathogen moves from its reservoir to a new host.

What are examples of routes of transmission?

Direct contact, indirect contact through contaminated objects, air, insects, and contaminated vehicles such as food, water, blood, medications, or solutions.

What is a portal of entry?

The point where the organism enters the new host, commonly through skin or the urinary, respiratory, or GI tract.

What is a susceptible host?

A host whose resistance is not sufficient to prevent the pathogen from surviving and reproducing.

How can the nurse break the infectious-agent link?

Identify the pathogen and begin appropriate treatment.

How can the nurse break the reservoir link?

Use employee-health measures, environmental sanitation, disinfection, and sterilization.

(Throw away items in a biohazard bag)

How can the portal-of-exit link be broken?

Contain secretions and body fluids, such as using respiratory hygiene and covering coughs and sneezes.

How can the route-of-transmission link be broken?

Use Standard Precautions, hand hygiene, appropriate transmission precautions/isolation, disinfection/sterilization, proper food handling, and avoid shaking contaminated linens.

How can the portal-of-entry link be broken?

Prevent pathogens from entering through vulnerable sites by using aseptic technique, catheter care, and wound care.

How can the susceptible-host link be addressed?

Recognize and protect high-risk patients, including patients with cancer or AIDS, transplant recipients, infants, older adults, diabetics, surgical patients, and burn patients.

A nurse performs meticulous Foley catheter care. Which link in the chain is the nurse primarily protecting?

The portal of entry, because catheter care helps prevent microorganisms from entering the urinary tract.

A nurse disinfects shared equipment between patients. Which link is primarily being interrupted?

The route of transmission because pathogens are prevented from passing through contaminated equipment.

What inadequate primary defenses increase infection risk?

Broken skin or mucosa, Traumatized tissue, Decreased ciliary action, Obstructed urine flow, Decreased mobility

What inadequate secondary defenses increase infection risk?

Suppression of WBCs or the inflammatory response by disease or medications.

What additional patient factors increase infection risk?

Older age, poor nutrition, and stress; stress-related ACTH production can decrease resistance to infection.

Which patient is at greater risk for an HAI: a healthy patient hospitalized overnight or an older critically ill patient with a Foley and central line? Why?

The critically ill patient with invasive devices because invasive devices, critical illness, and hospitalization increase HAI risk.

What is a localized infection?

An infection limited to one specific part of the body, such as an infected incision or open wound.

What is a systemic infection?

A generalized infection involving the body, often through circulating body fluids or blood; examples include septicemia or sepsis.

A patient's surgical incision is red and draining pus, but there are no generalized findings. Is this more consistent with localized or systemic infection?

Localized infection because the infectious process is confined to one area.

What occurs during the incubation stage?

It is the time between pathogen invasion and the onset of symptoms.

What occurs during the prodromal stage?

Early, vague, nonspecific symptoms appear.

What occurs during the full stage of illness?

Specific signs and symptoms of the illness are present.

What occurs during the convalescent stage?

The patient is recovering and acute symptoms disappear; recovery time varies with health status and infection severity.

A patient reports vague fatigue, weakness, and a headache before developing disease-specific symptoms. Which stage is this?

Prodromal stage.

What is the difference between nonspecific and specific defenses?

Nonspecific defenses protect against microorganisms regardless of previous exposure, while specific immune defenses target identifiable infectious agents.

What is antibody-mediated or humoral immunity?

B lymphocytes recognize an antigen and produce specific antibodies/immunoglobulins against it.

What is cell-mediated immunity?

A delayed immune response involving mainly T cells, killer cells (cytotoxic t cells), and macrophages that directly attack foreign invaders without antibodies.

What is naturally acquired active immunity?

Exposure to a live pathogen causes disease and the person's body produces its own antibodies. It is long duration.

What is artificially acquired active immunity?

A vaccine or toxoid stimulates the person's own antibody production without producing symptoms of the disease.

What is naturally acquired passive immunity?

Antibodies passed from mother to baby. It is short duration.

What is artificially acquired passive immunity?

Receiving preformed antibodies by injection, such as gamma globulin.

What is medical asepsis?

Clean technique that reduces the number of pathogens. Hand hygiene is the most important measure.

When is medical asepsis used?

Examples include medication administration, enemas, tube feedings, and daily hygiene.

What is surgical asepsis?

Sterile technique designed to eliminate all pathogens.

When is surgical asepsis used according to the PowerPoint?

During dressing changes, catheterization, and surgical procedures.

A nurse performs routine bathing on a patient. Is medical or surgical asepsis appropriate?

Medical asepsis, because daily hygiene uses clean technique.

A nurse inserts a urinary catheter. Is medical or surgical asepsis required?

Surgical asepsis/sterile technique.

What is the key exam difference between medical and surgical asepsis?

Medical = reduce pathogens/clean. Surgical = eliminate pathogens/sterile.

When should soap and water be used instead of alcohol-based hand rub?

When hands are visibly soiled or contaminated with blood/body fluids, before eating, and after using the restroom.

How long should hands be scrubbed with soap and water according to the PowerPoint?

At least 20 seconds.

When can alcohol-based hand rub be used?

When hands are not visibly soiled; rub until the product is dry.

What are the 5 moments for hand hygiene?

Before touching a patient, Before a clean/aseptic procedure, After body-fluid exposure risk, After touching a patient, After touching the patient's surroundings

You adjust a patient's bedside table without touching the patient. Do you need hand hygiene afterward?

Yes. Hand hygiene is required after touching the patient's surroundings even if the patient was not touched.

Does wearing gloves eliminate the need for hand hygiene?

No. Hand hygiene is still required as indicated, including after PPE removal.

What are Standard Precautions?

The minimum infection-prevention practices used for all patient care, regardless of whether infection is suspected or confirmed.

Are Standard Precautions used only for patients known to have an infection?

No. They apply to every patient.

What measures are included in Standard Precautions in the PowerPoint?

Hand hygiene, gloves, gown, mask/eye protection when appropriate, accommodation, management of body-fluid spills, clinical waste, linen, exposure prevention, environmental cleaning, and patient-care equipment.

What interventions help protect a susceptible host from infection?

Immunizations and screening healthcare staff help protect susceptible hosts and reduce exposure to infection.

What are examples of breaking the route of transmission?

Hand hygiene, appropriate PPE, proper sharps disposal, vector control, adequate refrigeration, and transmission-based precautions.

How can the nurse control a portal of exit?

Keep wounds covered with a dry intact dressing, use hand hygiene/gloves with body fluids, and cover the nose and mouth when coughing or sneezing.

What room and PPE are used for Droplet Precautions?

A private room is preferred. The nurse wears a surgical mask when within about 3–5 feet of the patient or providing direct care. If the patient must leave the room, the patient wears a mask during transport.

Examples in the PowerPoint include influenza, pertussis, mumps, meningitis, H. influenzae, and adenovirus. Exam clue: Think large respiratory droplets → surgical mask, not N95.

What room setup and PPE are used for Contact Precautions?

The patient may be placed in a private room or appropriately cohorted. Wear gown and gloves when contacting the patient or the patient's environment. Use dedicated equipment when possible; shared equipment must be cleaned and disinfected before another patient uses it.

Exam clue: Contact precautions are not just about touching the patient. The patient's environment and contaminated equipment can also transmit organisms.

What room and respiratory protection are required for Airborne Precautions?

Use a private negative-airflow room with the door closed. Air is exhausted outdoors or appropriately filtered. For a patient with TB, the nurse wears an approved N95 respirator. If the patient leaves the room, the patient wears an isolation mask during transport.

Exam clue: Think: Airborne → negative pressure + N95 for TB + door closed.

Why does incomplete bladder emptying increase the risk for a UTI?

If the bladder does not empty completely, urine remains in the bladder instead of being eliminated.

Your course material identifies incomplete bladder emptying as a factor associated with urinary tract infections.

Exam connection: When thinking about infection risk, recognize urinary stasis/incomplete emptying as a problem that makes urinary infection more likely.

How can an enlarged prostate contribute to a UTI?

An enlarged prostate can obstruct the bladder outlet, preventing the bladder from emptying completely.

Your course diagram connects bladder outlet obstruction → incomplete emptying → increased UTI risk.

Exam clue: If a scenario gives you an older patient with an enlarged prostate and poor bladder emptying, recognize urinary obstruction as an infection-risk factor.

What organism in the provided material is associated with the urogenital tract and may be important when thinking about UTI?

Escherichia coli (E. coli) is listed among organisms associated with the urogenital tract.

Exam connection: For this course section, connect E. coli → urogenital tract while remembering that the specific organism causing an infection is confirmed through appropriate testing rather than assumed from symptoms alone.

Why does a Foley catheter increase the patient's risk for a UTI?

A Foley catheter is an invasive device that creates a potential portal of entry for microorganisms into the urinary tract.

Your PowerPoint specifically gives a UTI after Foley catheter insertion as an example of an iatrogenic infection.

Nursing connection: Prevent infection by using sterile/aseptic technique during catheterization and proper catheter care to protect the urinary portal of entry.

What should the nurse recognize about obstructed urine flow and infection risk?

Obstructed urine outflow is an inadequate primary defense that increases susceptibility to infection. Therefore, urinary obstruction or difficulty completely emptying the bladder should be recognized as an infection-risk factor.

Exam clue: If asked which finding makes a patient more susceptible to infection, obstructed urine flow is one of your PowerPoint's listed answers.

What is especially important about C. difficile spores in the environment?

C. difficile is a spore-forming bacterium, and its spores can survive in the environment for up to about 70 days according to the PowerPoint. Because it spreads through contact and persists on environmental surfaces, environmental management is an important part of preventing transmission.

Exam clue: Think: C. diff = spores + contact spread + environmental persistence.

Why must soap and water be used for C. difficile?

C. difficile spores are resistant to alcohol-based hand disinfectants, so the nurse should wear gloves and wash hands with soap and water rather than relying on alcohol hand sanitizer.

Exam scenario: You leave a C. diff patient's room and see an alcohol sanitizer dispenser. → Do not substitute the sanitizer for handwashing. Wash with soap and water.

What nursing action helps reduce infection risk from indwelling devices?

Remove indwelling devices, such as urinary catheters, as soon as they are no longer necessary because invasive devices increase the risk for healthcare-associated infections.

When are Transmission-Based Precautions used?

When certain organisms require additional precautions beyond Standard Precautions.

What are the 3 major Transmission-Based Precautions?

Airborne, droplet, and contact.

Can a patient require more than one type of Transmission-Based Precaution?

Yes. Precautions may be combined when a disease has multiple routes of transmission.

Why are Airborne Precautions used?

For microorganisms carried in small particles/droplet nuclei that can remain suspended in the air for long periods.

What room is required for Airborne Precautions?

A private negative-airflow room with the door closed.

What respiratory protection does the PowerPoint specify for a patient with TB?

An approved N95 respirator.

What should the patient on Airborne Precautions wear when being transported?

An isolation mask.

A patient with TB must leave the negative-pressure room for a diagnostic test. Who wears what?

The healthcare worker uses the required N95 respirator, and the patient wears a mask during transport.

How is droplet transmission described?

Larger droplets from an infected person travel a short distance and land on another person's conjunctiva, nasal mucosa, or mouth.

What illnesses are listed as examples requiring Droplet Precautions?

Meningitis, pertussis, mumps, H. influenzae, adenovirus, and influenza.

What PPE is emphasized for Droplet Precautions?

A surgical mask when within approximately 3–5 feet of the patient or providing direct patient care.

What should a patient on Droplet Precautions wear during transport?

A mask.

A patient with influenza needs direct care. Does the nurse need an N95 based on this PowerPoint?

No. Influenza is listed under Droplet Precautions, for which the PowerPoint specifies a surgical mask during close/direct care.

What is direct-contact transmission?

Physical transfer of microorganisms through body-surface-to-body-surface contact between a susceptible host and an infected or colonized person.

What is indirect-contact transmission?

Contact with a contaminated object or intermediate source, such as equipment, needles, dressings, unwashed hands, or unchanged gloves.

What PPE is used for Contact Precautions according to the PowerPoint?

Gown and gloves when contacting the patient or the patient's environment.

What should be done with equipment used for a patient on Contact Precautions?

Dedicate equipment to that patient when possible. If equipment must be shared, clean and disinfect it before another patient uses it.

A nurse uses a blood-pressure cuff on a patient with C. diff. What should happen before using it on another patient?

Ideally use dedicated equipment; if shared equipment is unavoidable, it must be properly cleaned and disinfected first.

What determines which PPE the nurse should wear?

The expected exposure and the type of precaution required: Standard, Contact, Droplet, or Airborne.

What is the basic CDC sequence for putting on full PPE?

Gown → mask/respirator → goggles/face shield → gloves. This sequence comes from the CDC PPE resource used to supplement the PowerPoint.

What is the basic CDC sequence for removing full PPE?

Gloves → goggles/face shield → gown → mask/respirator → hand hygiene. Handle contaminated surfaces carefully.

Why are gloves generally removed first when doffing PPE?

They are likely to be highly contaminated, so removing them early reduces contamination of other surfaces.

What part of goggles or a face shield should the nurse touch when removing them?

The headband or earpieces, not the contaminated front.

What part of a mask or respirator should NOT be touched during removal?

The front, because it is considered contaminated. Remove it by the ties or elastics.

Why are masks and respirators important for respiratory infections?

Respiratory viruses can spread into the air during talking, coughing, and sneezing; masks block germs, while properly used respirators filter particles as air moves in and out.

What is a PAPR?

A powered air-purifying respirator that uses a blower to move air through filters into a facepiece, hood, or helmet and provides higher-level respiratory protection against aerosolized pathogens.