Nosocomial infections

Question 1

Portals of Central line associated BSI?

Answer 1

1) Peripheral Venous catheters
2) Central Venous catherters (CVC)
3) Peripherally inserted Central catheter

Question 2

Pathogensis of CLABSI

Answer 2

Bacteria extraluminal or intraluminal surface of catheter→ adhere→ biofilm**

they both cause local and systemic infections

Question 3

Complications of CLABSI

Answer 3

1) local infections: Cellulitis, abscess formation, septic
thrombophlebitis
2) Systemic infections : CLASBI, metastatic infectious foci, infective endocarditis

Question 4

Diagnosis of CLABSI

Answer 4

2 sets of culture, BOTH from the preipheral vein & through the catherter -ALWAYS

• Note: presence of CVC inserted >48hrs ago & sample taken through CVC is positive at least 2 hours before
  sample taken from peripheral vein & culture taken from pus at insertion site (if present)

Question 5

What are the most common HAI?
*HAI: Hospital aquired infections

Answer 5

1) CLABSI- Central line associated blood stream infections
2) UTIs
3) VAP -Ventilator associated pneumonia
4) Surgical site infections

Question 6

Pathogens Responisble for CLABSI?

Answer 6

1) Contamination of infusate: mostly gram (-) rods
(Enterobacter spp, Citrobacter spp, serratia spp)
2) Contamination of catheter hub (intraluminal): gram (+) cocci (s. aureas & CoNS)
3) Contamination of skin at insertion site (extraluminal): gram (+) cocci (s. aureus &
CoNS)
4) Fungi: Candida assc. w/ total parenteral nutrition (TPN)

Question 7

Traetment of CLABSI

Answer 7

1) remove catheter- Esp. if pateint is septic (IMMEDIATELY)
2) give IV abx –> bactericidal

Question 8

Prevention of CLABSI

Answer 8

1) remove unnecessary catheters
2) follow proper insertion practices
3) hand hygiene
4) skin antisepsis (chlorhexidine)
5) choose proper insertion sites (avoid femoral)
6) hub/access port disinfection
7) daily maintenance
8) no prophylactic antibiotics

Question 9

Portal of Nosocomial and Ventilator assocaited pneumonia (VAP)

Answer 9

VAP: aspiration, intubation, biofilm,
contaminated secretions (droplets), contaminated
respiratory equipment

Question 10

Diagnosis of Nosocomial and VAP

Answer 10

1) Nosocomial: pneumonia in patient ≥ 48hrs after hospital admission
2) VAP: pneumonia in patient ≥ 48hrs after intubation

Tests: sputum, bronchoalveolar lavage & blood cultures necessary

Question 11

Pathogens Responsible for nosocomial and VAP

Answer 11

1) gram (+) S. aureus
2) gram (-) rods (Pseudomonas aeruginosa, Klebsiella spp, E.coli, Acinetobacter spp.)
–> these are usually MDR strains

*Majority of nosocomial & VAP are due to gram (-) rods
*MDR: Multiple drug resitant

Question 12

Nosocomial and VAP prevention measurments

Answer 12

1) avoid/ minimise intubation
2) oral care (chlorhexidine), tooth brushing
3) use silver coated endotracheal tubes-> to
remove mucus plugs
4) decrease pooling of secretion via;
elevation of head of bed, optimal tube cuff
pressure, continuous aspiration of secretions through tube, respiratory physiotherapy

Question 13

• Important
  Signs and symptoms of Surgical site infections

Answer 13

1) local signs : redness, purulent discharge at site of incision
3) Systemic : fever- if deep infection may lead to sepsis

Question 14

• Important
  Pathogens causing Surgical site infections

Answer 14

-CoNS , S.Aureus ,
enterococcus (group D)

Question 15

Prevention measurments of surgical site infections

Answer 15

1) ensure patients shower, don’t shave, **only
use abx when recommended, **
2) use chlorhexidine antiseptic to prepare skin,
3) surgical scrub ,
4) limit no of people in room,
5) sterile surgical equipment
6) don’t use prophylactic abx,
7) check wounds for infection, use standard dressings

Question 16

Signs and Symptoms of UTI’s

Answer 16

1) fever,
2) altered mental status,
3) lethargy,
4) costovertebral angle pain

Question 17

Pathogens causing UTI’s

Answer 17

1) gram (-) rods & enterococci,
2) E. coli: klebsiella, Enterobacter, Serratia, pseudomonas, citrovacter, enterococci

Question 18

Prevention measurments for UTI’s

Answer 18

1) avoid catheterisation if not indicated
2) place catheter aseptically,
3) check catheter daily, maintain close circuit
4) always wash hands after touching
catheter
5) don’t elevate urine collection bag above
bladder level
6) don’t use prophylactic antibiotics
7) don’t’ change catheter routinely

Question 19

What kind of HAI is this?

Answer 19

Surgical site infection

Question 20

What kind of HAI is this?

Answer 20

Systemic infection caused by CLABSI

Question 21

Name a few pathogens requiring airborne precautions

Answer 21

1. Documented or suspected pulmonary or laryngeal tuberculosis
2. Measles
3. Varicella infection (chickenpox)
4. Disseminated Zoster infection (Varicella virus reactivation)
5. COVID-19

Question 22

Name a few pathogens requiring droplet precautions

Answer 22

1. Invasive Haemophilus influenzae type b & meningococcal infections
2. Mycoplasma pneumoniae, pertussis, mumps, rubella & parvovirus B19
3. Influenza transmitted via droplets

Question 23

large droplet precautions?

Answer 23

patients in private room, no special air handling, door may be open, HC workers wear surgical mask
don’t remain suspended or travel as far.
-Produced during talking, coughing, sneezing, procedures.
-Host susceptible if lands on mucosal surfaces (nose, mouth, eye)

Question 24

Airborne precautions?

Answer 24

1) Patients placed in isolation rooms with NEGATIVE pressure
2) Room air must undergo at least 6 (preferentially 12) changes per hour – door ALWAYS CLOSE
3) N95 mask must be worn by anyone entering a room with a patient with suspected or confirmed Tuberculosis

• Airborne particles can remain suspended in air & travel long distances