Chapter 10: Wound infections and Antimicrobial Use

Question 1

What happens to the risk of SSI with each hour of surgery?

What three things can you do to reduce time?

Answer 1

Risk doubles

Adhere to Halstead’s principles, use sound technique, be efficient

Question 2

What effect does prolonged duration of anesthesia have on SSI risk?

Answer 2

Decreases body temp and impacts the immune system

Question 3

Is there a difference in SSI rate for wound closure with staples vs. skin sutures vs. intradermal?

Answer 3

No, no clear difference found

Question 4

What is a risk of overuse of antimicrobial prophylaxis?

Answer 4

Adverse effects and resistance

Question 5

What two comorbidities increase rate of SSI?

Answer 5

Endocrinopathy and obesity

Question 6

What is the most common bacteria to cause SSI?
What are four others?

Answer 6

Staph. pseud most common

Others: Staph aureus, Enterobacteria, Enterococcus, Pseudomonas

Question 7

Cefazolin is the most common perioperative antimicrobial for prophylaxis. What are two areas where you would use Cefoxitin instead?
Where might you use ampicillin instead of cefazolin?
Where might you use clindamycin instead of cefazolin?
What do you use for open fractures?

Answer 7

Cefoxitin: Hepatobiliary, lower GI
Ampicillin: Urogenital
Clindamycin: Oral/head/Neck

Open fractures: Cefazolin or Clindamycin +/- aminoglycoside or fluoroquinolone

Question 8

What generation cephalosporin is Cefoxitin?

Answer 8

2nd generation

Question 9

When should you discontinue perioperative antibiotics?

Answer 9

Within 24 hours of procedure

Question 10

When should you give your perioperative antibiotic? Re-dose?

Answer 10

Give within 60 minutes of first incision, re-dose q90

Question 11

Define Clean, clean-contaminated, contaminated, and dirty:

Answer 11

Clean: Elective, primary closure, no drains, no break in technique, no inflammation
Clean-contaminated: Controlled entry into hollow viscera, minor breaks in aseptic technique
Contaminated: Open, fresh trauma wound, incision into acute nonpurulent inflammation, major breaks in asepsis
Dirty: Pus encountered, perforated viscera, devitalized traumatic wound or >4hr old, contamination with foreign or fecal material

Question 12

If you can wait for culture results, what can you do for a superficial SSI in the meantime?

Answer 12

Topical therapy (chlorhexidine, mupirocin, honey)

Question 13

How often must the implant be removed if it develops a biofilm?

Answer 13

90% of the time

Question 14

What is the body’s contribution to biofilms?

Answer 14

The conditioning layer it puts down on the implant

Question 15

What is the infection rate for clean, clean-contaminated, contaminated, and dirty:

Answer 15

clean: 2 - 4.8%
clean-contaminated: 3.5 - 5% (5.9*)
contaminated: 4.6 - 12%
dirty: 6.7 - 18.1%