Surgical site infection

Question 1

What is the rate of SSI in gynaecology?

Answer 1

2-18%

Question 2

What is the rate of SSI in:

• Elective CS
• Emergency CS

Answer 2

Elective CS 4%

EmCS 3-15%

Question 3

What risk factors (patient, procedure) increase the risk of SSI?

Answer 3

Patient factors:

• Smoking
• Diabetes
• Immunosuppression
• Older age
• Active infection

Procedure factors:

• Emergency
• Open

Question 4

What pre-op interventions can reduce SSI?

Answer 4

• Treat active infection before operation.

- Smoking cessation (even 6 weeks before)

Question 5

Antibiotic prophylaxis principles:
When should abx be given?
When should repeat abx be given?

Answer 5

Prophylactic abx should be given 60 mins before knife to skin.

Prophylactic abx should be repeated after 4 hours or if excessive blood loss (>1.5L)

Question 6

List infection control practices to reduce risk of SSI.

By what % does these practices reduce the risk of SSI?

Answer 6

Infection control practices:

• Surgical scrubbing and anaesthetic hand washing
• Do not wear scrubs outside theatre.
• Use clippers not razors for hair removal; do not shave immediately prior to surgery.
• Chlorhexidine (better than iodine) skin prep in horizontal stripes.

Reduces SSI by up to 40%

Question 7

List surgical techniques to reduce risk of SSI

Answer 7

Surgical techniques:

• Minimise diathermy
• Avoid excessive traction on wound edges; use Alexis retractor
• Avoid excessive tension on sutures
• Effective haemostasis to reduce need for blood transfusion
• Keep tissues moist

Question 8

What other measures minimise SSI?

Answer 8

• Normothermia
• Limit traffic through operating theatre.
• Good glucose control
• Avoid blood transfusion where possible

Question 9

Prevention of SSI with obstetric operations:

By what % does antibiotic prophylaxis reduce SSI?

What antibiotics could you use for prophylaxis?

Answer 9

50%

Cefazolin 1g; 2g for obese women >100 kg.
Clindamycin or gentamicin if severe penicillin/cephalosporin allergy.

Question 10

Prevention of SSI with gynaecology operations:

What antibiotics could you use for prophylaxis?

Answer 10

Cefazoling 2g IV + metronidazole 500 mg IV
Augmentin 1.2g IV
Ceftriaxone 2g IV
Gentamicin 3 mg/kg if anaphylactic to penicillin/cephalosporin.

Question 11

Define healing by primary intention

Answer 11

Wound sutured initially after operation.

Heals to leave a minimal, cosmetically acceptable scar.

Question 12

Define healing by secondary intention

Define delayed primary closure.

Define secondary closure

Answer 12

Secondary intention: wound intentionally left open because of excessive bacterial contamination (esp. anaerobes) or when there is devitalised tissue.
Can be left open to heal completely without suturing.

Delayed primary closure: left open wound can be sutured within a few days.

Secondary closure: left open wound can be sutured much later when wound is clean and granulating.