Surgical site infection

Question 1

What is a surgical site infection?

Answer 1

An infection at the site of a surgical wound, usually within 1 week of surgery

• infection may prevent healing > separation of the wound edges or abscess formation in deeper tissues

Question 2

What is a superficial incisional surgical site infection?

Answer 2

infection in area of skin where the incision was made

Question 3

What is a deep incisional surgical site infection?

Answer 3

infection beneath the incision area in muscles and tissues.

Question 4

What is an organ or space surgical site infection?

Answer 4

infection in any area of the body other than skin, muscle and surrounding tissue that was involved in the surgery

Question 5

What is a clean wound?

Answer 5

an incision where:

• no inflammation is encountered during surgery
• no contamination
• respiratory, alimentary and genitourinary tracts are not entered

Question 6

What is a clean-contaminated wound?

Answer 6

an incision where:

• the respiratory, alimentary or genitourinary tract is entered
• but no contamination occurs

Question 7

What is a contaminated wound?

Answer 7

an incision where:

• a major break in sterile equipment occurs
• spilling of contents from GIT into the wound
• inflammation is encountered

Question 8

What is a dirty/infected wound?

Answer 8

known infection is present at time of surgery

• perforated viscera
• acute inflammation with pus

Question 9

What are some risk factors for surgical site infections?

Answer 9

• Dirty/contaminated operations
• Long procedures (>2 hours)
• Diabetes (hyperglycaemia impairs immune function and wound healing)
• Obesity (excess adipose tissue can impair wound healing)
• Smoking (impairs wound healing and immune function)
• Immunosupression

Question 10

What are the most common bacteria that cause surgical site infection?

Answer 10

• Staphylococcus
• Streptococcus
• Pseudomonas

Question 11

What are the clinical features of a mild surgical site infection?

Answer 11

erythema and tenderness without systemic symptoms

Question 12

What are the clinical features of a severe surgical site infection?

Answer 12

• purulent discharge
• tenderness
• hot to touch
  fever
• abscess formation
• systemic signs of infection

Question 13

What are the investigations for a surgical site infection?

Answer 13

• Wound swabs (organism and sensitive antibiotics)
• Blood tests (FBC, raised CRP and ESR)

Question 14

What is the management of a mild surgical site infection?

Answer 14

• analgesia
• regular wound dressing changes
• oral antibiotics

Question 15

What is the management of a severe surgical site infection?

Answer 15

• wound swabs
• IV antibiotics
• abscess = reopen wound for drainage and debridement
• Allow would to heal by secondary intention

Question 16

What are some differential diagnosis for a surgical site infection?

Answer 16

• Haemtoma
• Seroma
• wound dehiscence
• Allergic reaction to sutures or dressings

Question 17

What is a haematoma and what are the clinical features?

Answer 17

a bad bruise

• swelling, pain, possible discoloration WITHOUT fever or pus

Question 18

What is a seroma and what are the clinical features?

Answer 18

fluid accumulation under the skin

• swelling without erythema, fever or pus

Question 19

What is wound dehiscence and what are the clinical features?

Answer 19

• partial/total separation of wound edges due to failure of wound healing
• wound separation with potential exposure of underlying tissue usually without fever

Question 20

when should nasal decolonisation occur prior to surgery?

Answer 20

patients positive for staphylococcus aureus because it is a likely cause of surgical site infection

• nasal mupirocin in combination with chlorhexidine body wash

Question 21

which antiseptic is commonly used to prepare the skin prior to surgery?

Answer 21

alcohol-based solution of chlorhexidine

• NOT IF NEXT TO A MUCOUS MEMBRANE therefore use aqueous solution of chlorehexidine instead