Antimicrobial Surgical Prophylaxis - Block 1

Question 1

What are the common surgical pathogens?

Answer 1

Staph. aureus
Coagulase negative staph (epidermis and saprophyticus)

Question 2

How do we prepare a patient for surgery?

Answer 2

1. Ensure shower or bath
2. Chlorhexidine prepares the skin
3. Sometimes Pre op ABX for decolonization

Question 3

How do we screen for MRSA?

Answer 3

Colonization of nares with S. areus is an SSI risk factor:
IN mupirocin admin and chlorhexidine bathing

Question 4

Describe the counseling of Nasal MRSA decolonization?

Answer 4

Use mupirocin ointement in each nostril BID for 5 days (prior to surgery)
1. Clean hands for 15-20 sec before and after application
2. Tilt head back and use cotton swab to apply pea size amount of the ointment to inside of each nostril
3. Press your nostril together and massage for 1 min
4. Avoid eyes, if so, rinse with cold water

Question 5

How do you apply chlorhexidine?

Answer 5

1. Shampoo and rinse hair with normal shampoo
2. Using a clean washcloth, apply Hibiclens to all areas from the neck down
3. When covered, leave for 2 minutes then rinse
4. Don’t wash with any other soap/cleanser after Hibiclens
5. Don’t apply any further skin care to body

Question 6

RF of surgical site infection?

Answer 6

1. Age
2. Nutritional status
3. Diabetes
4. Smoking
5. Obesity
6. Coexisting infection
7. Resistance strains
8. Length of stary
9. Altered immune response

Question 7

Drugs of G+ coverage?

Answer 7

S. aureus and epidermis on skin incisions:
* Cefazolin

Question 8

Drugs of G- and anaerobic coverage?

Answer 8

If incision in on mucous membrane:
* Cefaxitin
* Cefotetan

Question 9

Cardiac surgery

Microbio, Tx, Notes

Answer 9

Microbio: S. aureus, epidermis, Corynebactium
Tx: Cefazolin 1 g Q8H for 48 H
* IN mupirocin BID for 5 days preop

Notes: >80kg should recieve 2 g of cefazolin
* For MRSA consider vancomycin

Question 10

Appendectomy

Microbio, Tx

Answer 10

Microbio: EGN bacilli, anaerobes
Tx: Cefoxitin or cefotetan 1g once
* OR cefazolin 1g + Metronidazole 1g once

Question 11

Colorectal surgery

Microbio, Tx

Answer 11

Microbio: EGN bacilli, anaerobes
Tx: PO - neomycin 1g + erythromycin base 1g at 1, 2, 11 pm preop plus bowel prep
* IV: cefoxitin or cefotetan 1g once

Question 12

According to the National Research Council classification of surgical site infection, antibiotic prophylaxis isnotrequired for:

A.Clean procedures
B.Clean–contaminated procedures
C.Contaminated procedures
D.Dirty procedures

Answer 12

D.Dirty procedures

Question 13

Which of the following is not considered patient-specific risk factors for surgical site infections?

A.Smoking history
B.Preoperative nutritional status
C.Male gender
D.Diabetes

Answer 13

C.Male gender

Question 14

According to the National Nosocomial Infection Surveillance System, which one of the following organisms ismost oftenisolated from surgical site infections?

A.Streptococcus pneumonia
B.Staphylococcus aureus
C.Escherichia coli
D.Enterococci sp.

Answer 14

B.Staphylococcus aureus

Question 15

Medications to consider for beta-lactam allergies?

Answer 15

Vancomycin, clindamycin

Question 16

In instances of MRSA risk, what would you use?

Answer 16

Vancomycin

Question 17

What is the ABX prophylaxis regimen for morbidly obese?

Answer 17

Cefazolin 2 g

Question 18

Describe the concepts of timing and admin of doses?

Answer 18

1. Drug should be delivered to the surgical site prior to initial incision (completed within 60 min prior to initial incision)
2. Bactericidal antibiotic concentrations should be maintained at the surgical site throughout the surgical procedure.
   * Repeated if its been longer than 2t1/2 or if blood loss exceeds 1.5L