Surgical site infection (I)

Question 1

Define surgical site infection.

Answer 1

Infection that occurs in the incision created by an invasive surgical procedure - major cause of morbidity and mortality

Question 2

When may surgical site infection occur?

Answer 2

Following a breach in tissue surfaces allowing normal commensals and other pathogens to initiate infection

Question 3

How common is surgical site infection?

Answer 3

Make up 20% of all healthcare-associated infections and at least 5% of patients undergoing surgery will develop a surgical site infection as a result

Question 4

What bacteria commonly cause surgical site infection?

Answer 4

• common cause of wound infection = Enterobacter (usually following cardiac or colonic surgery)
• 23% infections due to Staphylococcus aureus
• infection with other organisms e.g. Streptococcus pyogenes is rare

Question 5

What are some risk factors for surgical site infection? (8)

Answer 5

• old age
• poor glycaemic control
• obesity
• smoking
• renal failure
• immunosuppressed
• pre-operative shaving
• length of operation

Question 6

What are the clinical features of a surgical site infection? (4)

Answer 6

• spreading erythema
• localised pain
• pus or discharge from the wound
• pyrexia

Question 7

What are the main investigations done for surgical site infection and why? (4)

Answer 7

• wound swabs
• blood tests - markers of infection
• blood cultures - evidence of sepsis
• cross-sectional imaging - deeper collections or necrotising fasciitis

Question 8

What is the main management of surgical site infection?

Answer 8

Remove any sutures or clips to allow pus to drain + empirical antibiotic therapy

Question 9

What is involved in pre-operative care (surgical site infection)? (3)

Answer 9

• do not routinely remove body hair and if you do, use electric clippers NOT razors
• Abx prophylaxis –> if placement of prosthesis or valve
• patient advice - encourage weight loss, smoking cessation, optimise nutrition and ensure good diabetic control

Question 10

What is involved in intra-operative care (surgical site infection)? (4)

Answer 10

• prepare skin with alcoholic chlorhexidine
• cover surgical site with dressing
• do not give insulin routinely to patients with diabetes
• do not use wound irrigation or intracavity lavage

Question 11

What should NOT be used on wounds that are healing by primary intention?

Answer 11

Topical antimicrobial agents