infection prevention week 3

7 exam questions

What is the #1 method for preventing infection?

Hand hygiene. It is the most important infection-prevention action.

When should a nurse perform hand hygiene?

Before and after all patient interactions; before putting on and after removing gloves

How long should hands be rubbed vigorously during hand hygiene?

15–20 seconds

What hand hygiene method must be used for C. difficile?

Soap and water. Never alcohol-based sanitizer

Why is alcohol hand sanitizer ineffective against C. difficile?

Alcohol-based sanitizer does not kill C. diff spores

What is asepsis?

Being free from disease-causing microorganisms.

What is contamination?

The introduction of microorganisms.

What is infection?

The invasion and multiplication of pathogens.

When should aseptic/sterile technique be used?

When breaking skin, entering a sterile cavity, or performing an invasive procedure.

What are the 4 major types of infectious agents?

Bacteria, viruses, fungi, and parasites.

What findings indicate a local infection?

Redness, swelling, and warmth at the affected/wound site.

What findings indicate a systemic infection?

Fever, malaise, and increased WBC count.

What is a healthcare-associated infection (HAI)?

An infection contracted in a healthcare setting; it may appear during the stay or after discharge.

What is the most preventable contributing factor to HAIs?

Insufficient hand hygiene

What are the most common sites of HAIs?

Urinary tract, surgical wounds, and respiratory tract.

What nursing action reduces catheter-associated infection risk?

Remove urinary catheters as soon as clinically appropriate

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

Agent → Reservoir → Portal of Exit → Transmission → Portal of Entry → Susceptible Host.

How can a nurse stop the chain of infection?

Break any one of the six links through appropriate infection-prevention practices.

What nursing actions break the infectious-agent link?

Correctly clean, disinfect, or sterilize equipment/articles before use.

What are common reservoirs for microorganisms?

Humans, patient flora, plants, animals, food, water, feces, and the environment.

What nursing action helps eliminate a microorganism reservoir?

Change wet/soiled dressings and properly dispose of contaminated linens, feces, and urine.

What are common portals of exit?

Blood, intestinal tract, respiratory tract, skin, and mucous membranes.

How can a nurse interrupt the portal-of-exit link?

Cover coughs/sneezes and avoid coughing, sneezing, or talking over sterile fields/open wounds.

What are the 3 major modes of transmission?

Direct, indirect, and airborne transmission.

What is direct transmission?

Spread through touch, kissing, bites, sexual contact, or droplets within about 3 feet.

What is indirect transmission?

Spread by contaminated objects/vehicles or vectors such as animals and insects.

What are common portals of entry?

Blood, GI tract, respiratory tract, mucous membranes, and non-intact skin.

What nursing intervention protects a portal of entry during catheter insertion?

Use sterile technique every time.

Who is considered a susceptible host?

Anyone with impaired natural defenses, such as from age, illness, malnutrition, or immunosuppression.

How can nurses protect susceptible hosts?

Maintain skin integrity, promote adequate nutrition, and encourage immunizations.

What are standard precautions used for?

Every patient, every time, regardless of known infection status.

What body substances are covered by standard precautions?

Blood, body fluids, secretions/excretions except sweat, nonintact skin, and mucous membranes

Are transmission-based precautions used instead of standard precautions?

No. They are used in addition to standard precautions.

What PPE/setup is used for contact precautions?

Gown + gloves + dedicated patient equipment.

What conditions require special contact precautions?

C. difficile, norovirus, and unexplained/infectious diarrhea.

What PPE/setup is used for droplet precautions?

Mask and eye protection. Droplets travel about 3 feet; influenza is an example.

What does the airborne mnemonic “MTV” stand for?

Measles, Tuberculosis, Varicella.

What PPE/setup is required for airborne precautions?

N95 respirator + negative-pressure room.

What are protective/reverse precautions used for?

Protect immunocompromised patients using HEPA filtration, strict hand hygiene, and screened visitors.

What are the highest-yield antimicrobial rules from this lecture?

Obtain cultures before antibiotics; antibiotics do not treat viral infections.

A nurse is caring for a patient with Clostridium difficile. Which action is most appropriate after providing care?

A. Use alcohol-based hand sanitizer
B. Wash hands with soap and water
C. Remove gloves without performing hand hygiene
D. Wipe hands with an antiseptic cloth

B. Wash hands with soap and water

Rationale: Alcohol-based sanitizer does not kill C. diff spores. Soap and water is required.

Which nursing action is the most effective method for preventing healthcare-associated infections?

A. Wearing gloves during all patient interactions
B. Administering prophylactic antibiotics
C. Performing proper hand hygiene
D. Placing all patients in private rooms

C. Performing proper hand hygiene

Rationale: The lecture identifies hand hygiene as the #1 infection-prevention method.

The nurse is preparing to insert an indwelling urinary catheter. Which technique should be used?

A. Clean technique
B. Medical asepsis only
C. Sterile technique
D. Standard precautions without sterile supplies

Answer: C. Sterile technique

Rationale: Sterile technique should be used for invasive procedures, including catheter insertion, to protect the portal of entry.

Which sequence correctly identifies the chain of infection?

A. Reservoir → Agent → Entry → Exit → Transmission → Host
B. Agent → Reservoir → Portal of Exit → Transmission → Portal of Entry → Susceptible Host
C. Agent → Exit → Reservoir → Host → Entry → Transmission
D. Host → Reservoir → Agent → Transmission → Exit → Entry

B. Agent → Reservoir → Portal of Exit → Transmission → Portal of Entry → Susceptible Host

Rationale: All six links must be present for infection to occur. Breaking any one link can stop transmission.

A patient has influenza. Which transmission-based precaution should the nurse implement?

A. Contact
B. Airborne
C. Droplet
D. Protective

Answer: C. Droplet

Rationale: Influenza is the lecture example for droplet precautions, which involve droplets traveling about 3 feet.

Which patient requires airborne precautions?

A. Patient with influenza
B. Patient with C. difficile
C. Patient with tuberculosis
D. Patient with infectious diarrhea

Answer: C. Patient with tuberculosis

Rationale: Remember MTV = Measles, TB, Varicella for airborne precautions. Airborne precautions require an N95 respirator and negative-pressure room

A nurse obtains an order for antibiotics for a patient with suspected bacterial infection. Which action should occur first?

A. Administer the antibiotic immediately
B. Obtain the ordered culture specimen
C. Repeat the patient's WBC count
D. Place the patient on contact precautions

Answer: B. Obtain the ordered culture specimen

Rationale: Cultures should be obtained before starting antibiotics so the causative pathogen can be identified

Which patient is at greatest risk for becoming a susceptible host?

A. Healthy young adult with intact skin
B. Patient receiving chemotherapy with poor nutritional status
C. Patient with a minor headache
D. Patient exercising regularly with adequate nutrition

Answer: B. Patient receiving chemotherapy with poor nutritional status

Rationale: Cancer, immune dysfunction, drug therapy, and malnutrition decrease natural defenses and increase infection susceptibility

A nurse experiences a needlestick injury from a contaminated needle. Which action should the nurse take first?

A. Wait for symptoms to develop
B. Complete an incident report before cleaning the area
C. Encourage bleeding and wash the site with soap and water
D. Begin antibiotics immediately

Answer: C. Encourage bleeding and wash the site with soap and water

Rationale: Immediate actions after bloodborne exposure include encouraging bleeding, washing with soap and water, reporting the incident, and completing an injury report

Which statement by a nursing student indicates correct understanding of standard precautions?

A. “I only use standard precautions when infection is confirmed.”
B. “Standard precautions are replaced by transmission-based precautions.”
C. “Standard precautions are used with every patient, every time.”
D. “Standard precautions apply only to blood exposure.”

Answer: C. “Standard precautions are used with every patient, every time.”

Rationale: Standard precautions apply to all patients, including exposure to blood, body fluids, secretions/excretions except sweat, nonintact skin, and mucous membranes. Transmission-based precautions are added when needed.

Which WBC is associated with bacterial vs. viral infections?

Neutrophils → bacterial infection
Lymphocytes → viral infection

What antibiotic classes are identified in the lecture?

Penicillins, cephalosporins, tetracyclines, quinolones, sulfonamides, macrolides, aminoglycosides

What are examples of penicillins from the lecture?

Ampicillin, amoxicillin, penicillin G, and Pen VK.

What are examples of cephalosporins and tetracyclines from the lecture?

Cephalosporins: Keflex, Ceftin, Omnicef
Tetracycline: Doxycycline

What are examples of quinolones, sulfonamides, and macrolides?

Quinolones: ciprofloxacin, Levaquin, Avelox
Sulfonamide: Bactrim
Macrolides: azithromycin, clarithromycin, AZithromycin

What serious adverse effects does the lecture associate with aminoglycosides?

Ototoxicity + nephrotoxicity. Monitor hearing/vestibular symptoms and creatinine.

What are MRSA and VRE?

MRSA: Methicillin-resistant Staphylococcus aureus
VRE: Vancomycin-resistant Enterococci