Surgical Antibiotics

Question 1

Define surgical site infection (SSI).

Answer 1

An infection related to an operative procedure that occurs at or near the surgical incision within 30 days of the procedure or within 90 days if prosthetic material is implanted at surgery.

Question 2

List the endogenous sources which allow SSIs to develop.

Answer 2

• skin bacteria can translocate to sterile site.
• GI tract spillage can contaminate sterile peritoneal cavity.
• seeding of operative site from distant site.

Question 3

List the exogenous sources which allow SSIs to develop.

Answer 3

• surgical team.
• surgical instruments.
• theatre environment.

Question 4

What are some patient related risk factors which can increase development of SSI?

Answer 4

Obesity
Extreme of age
Smoking status
Malnutrition 
Concomitant disease
Immunosuppressed
Prolonger post-operation stay

Question 5

What are some operation related risk factors which can increase development of SSI?

Answer 5

Pre-operative skin preparation
Implant insertion
Surgical drains
Surgical technique
Cleanliness - theatre and instruments
Type of surgery
Prolonger surgery = >2 hours

Question 6

What is antibiotic prophylaxis?

Answer 6

prevention of infection complications using antimicrobial therapy.

Question 7

What is surgical antibiotic prophylaxis (SAP)?

Answer 7

use of antibiotics to prevent infectious complications at the surgical site.

Question 8

Describe a clean operation.

SAP not required if uncomplicated and non-prosthetic.

Answer 8

Operations in which no inflammation is encountered and the respiratory, alimentary or genitourinary tracts are not entered. There is no break in aseptic operating theatre technique.

Question 9

Describe clean-contaminated operation.

SAP required.

Answer 9

Operations in which the respiratory, alimentary or genitourinary tracts are entered but without significant spillage

Question 10

Describe contaminated operation.

Sap required.

Answer 10

Operations where acute inflammation (without pus) is

encountered, or where there is visible contamination of the wound.

Question 11

Describe dirty operation.

SAP required and continued post-op.

Answer 11

Operations in the presence of pus, where there is a previously perforated hollow viscus, or compound/open injuries more than four hours old.

Question 12

What is the goal of SAP?

Answer 12

To ensure antimicrobial tissue concentration
remains above the MIC for pathogens:
- at time of incision AND
- throughout the procedure