Post-operative wound infection

Senior surgical review should be arranged.
Early discussion with infection specialist is required for all patients who are unstable.

Classification of Surgical Wounds

Clean	An uninfected operative wound in which no inflammation is encountered and in which the respiratory, GI, or genio-urinary tracts are not entered. e.g. elective orthopaedic surgery.
Clean-contaminated	Operative wounds in which the respiratory, GI, genito-urinary tract is entered under controlled conditions and without unusual contamination. e.g. elective abdominal or gynaecological surgery.
Contaminated	Open, fresh, or accidental wounds; operations with major breaks in sterile technique or gross spillage from the gastrointestinal tract; and incisions in which acute, non-purulent inflammation is encountered.
Dirty/infected	Old traumatic wounds with retained devitalised tissue, and those that involve existing clinical infection.

Treat as mild infection if NEWS <5, a small area of surrounding skin or soft tissue infection, no pus draining from the wound and no concern with regard to deep infection.

Required Investigations

Send a wound swab for culture.
Blood cultures (10mls in each bottle)
Where pus is expressed from the wound send pus in a universal container.
If patient not improving is a deep infection, space or organ infection possible, consider imaging.
If collection/abscess present consider drainage.

For dirty wounds:

Debrided tissue and pus should be sent to microbiology in white top universal containers.

Clean wound

Treat as mild infection if NEWS <5, only a small area of surrounding skin or soft tissue infection, no pus draining from the wound and no concern with regard to deep infection.

Mild infection, recommended total duration 5 days

Recommended antimicrobial	Flucloxacillin 1g every 6 hours orally
Penicillin allergy OR Previous MRSA (check sensitivities)	Doxycycline 100mg every 12 hours orally

Moderate to severe infection, recommended total duration 7 days (IV and oral)

Recommended antimicrobial	Flucloxacillin 2g every 6 hours IV
Penicillin allergy OR Previous MRSA	Vancomycin IV (use NHS Lothian Calculator located AMT intranet page) choose trough 10-15 mg/L

Clean-contaminated or contaminated

Treat as mild infection if NEWS <5, only a small area of surrounding skin or soft tissue infection, no pus draining from the wound and no concern with regard to deep infection.

Mild infection, recommended total duration 5 days

Recommended antimicrobial

Co-amoxiclav 625mg every 8 hours orally

Penicillin allergy OR Previous MRSA (check sensitivities) OR Frail elderly

Co-trimoxazole 960mg every 12 hours orally

AND

Metronidazole 400mg every 8 hours orally.

MRSA is not always sensitive to Co-trimoxazole. If not improving after 24-48 hours discuss with infection specialist.

Moderate to severe infection, recommended total duration 7 days (IV and oral)

Recommended antimicrobial

Flucloxacillin 2g every 6 hours IV

AND

Gentamicin IV (use NHS Lothian Calculator located AMT intranet page)

AND

Metronidazole 400mg every 8 hours orally (IV if oral route not available)

Penicillin allergy OR Previous MRSA

Vancomycin IV (use NHS Lothian Calculator located AMT intranet page)

choose trough 10-15 mg/L

AND

Gentamicin IV (use NHS Lothian Calculator located AMT intranet page)

AND

Metronidazole 400mg every 8 hours orally (IV if oral route not available)

Dirty wound

Treat as moderate-severe Clean-contaminated or Contaminated wounds.

If patient has severe organ dysfunction or septic shock:

Discuss with microbiology
ADD Clindamycin 1200mg every 6 hours IV for patient in septic shock (to the regimen advised)
Surgical intervention to remove devitalised tissue is key to gaining source control.

Consider need for tetanus immunoglobulin and vaccination.

Consider human IV immunoglobulin in severe Group A Streptococcal infections.