1. Surgical Infection Society Resident Corner

2. Surgical Infections
Prophylaxis

3. Surgical Site Infection (SSI)
Account for 14-16% of all hosp-acquired infections
2-5% of all surgical patients will develop SSI
Thus between 1 to 2 million SSI’s occur annually in the U.S.
SSI increases LOS in hospital
average 7.5 days
Excess cost per SSI:
*US national costs: $ million/year

4. Key points in Preventing Surgical Infections
Antibiotic prophylaxis
Drugs- which when, how many doses?
Non antibiotic measures- evidence based
Hair removal
Normothermia
Oxygen supplementation
Normoglycemia

5. Principles of Surgical Prophylaxis
Antibiotic stewardship is essential – narrow the agent used as much as possible.
What are the most likely organisms in the operative field?
It is essential to know drug half-life.
Re-dose in long cases that extend across half-lives
Or in cases with considerable blood loss – sterilizing the floor”
Drug should be given within 1 hour of incision
But time should be allowed for antibiotic to circulate
Single pre-op dose is adequate for most cases
Caution must be exercised against the potential side effects of the agent choosen (eg C.Diff colitis or nephrotoxicity)
Remember potential antibiotic exposure from prior hospitalization(s)

6. Surgical Prophylaxis Cefazolin Half - 2 hr 1-2 gr pre-op,
Should be re-dosed if case goes longer than 4 hours
Cefotetan or cefoxitin-
Good for colonic cases, or involving anaerobes
Half-life - Cefotetan- 4hrs; - cefoxitin- 1 hr

7. If patient is allergic to Penicillin
Should always try to assess degree of allergy – Nausea is not an allergy
If allergic – options include
Vancomycin – need to exercise with rapidly shifting vascular volumes
Vancomycin I gr IV
Should be started 1 hr pre-operatively, slow infusion (to avoid red man syndrome) – usually over a period of one hour infusion
Clindamycin – Very highly associated with C.Diff
For colonic cases
clindamycin or metronidazole combos

8. Treatment agents - Quiz
Surgical Infections
Treatment agents - Quiz

9. Which one of the following are/is characteristic of Tetracyclines
A. Bactericidal
B. activity against Mycobacterium tuberculosis
C. Discoloration of teeth
D. Risk of Superinfection
E. Narrow spectrum

10. Which one of the following are/is characteristic of Tetracyclines
A. Bactericidal
B. activity against Mycobacterium tuberculosis
C. Discoloration of teeth
D. Risk of Superinfection
E. Narrow spectrum

11. Tetracyclines
Active against many gram negative and most gram positive organisms
Alters ribosomal protein synthesis
It is bacteriostatic

12. Which one of the following are/is characteristic of Aminoglycosides
A. Active against a broad spectrum of Gram negative Aerobes
B. Emergence of Resistant bacterial strains does not occur
C. narrow margin between therapeutic and toxic levels
D. nephrotoxicity
E. Ototoxicity

13. Which one of the following are/is characteristic of Aminoglycosides
A. Active against a broad spectrum of Gram negative Aerobes
B. Emergence of Resistant bacterial strains does not occur
C. narrow margin between therapeutic and toxic levels
D. nephrotoxicity
E. Ototoxicity

14. Aminoglycosides Aminoglycosides bind to the 30s ribosomal subunit
They interfere with the proof-reading step
Disrupt the integrity of the bacterial cell membrane
Aminoglycosides are useful primarily in infections involving aerobic, Gram-negative bacteria, such as Pseudomonas, Acinetobacter, and Enterobactere

15. Inhibits cell wall synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

16. Inhibits cell wall synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

17. Impairment of bacterial DNA synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

18. Impairment of bacterial DNA synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

19. Disruption of membrane barrier function
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

20. Disruption of membrane barrier function
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

21. Disruption of ribosomal protein synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

22. Disruption of ribosomal protein synthesis
A. Amphotericin B
B. Penicillin
C. Cephalosporins
D. Aminoglycosides
E. Quinolones

23. Surgical Infection Society Resident Corner