2. Introduction
Surgical infection is major problem in surgical practice.
In 1992, the US Centers for Disease Control (CDC) revised its
definition of 'wound infection', creating the definition 'surgical site
infection' (SSI) to prevent confusion between the infection of a
surgical incision and the infection of a traumatic wound.
Accounts for 15-25% of all surgical infections & increased cost to
healthcare.
3. Definition
The infection of a wound can
be defined as the invasion of
organisms through tissues
following a breakdown of local
& systemic host defences
leading to local & systemic
presentation.
5. Important Definitions
SSI
Is an infected incised wound or deep organ space.
SIRS
Is the body’s systemic response to an infected wound.
MODS
Is the effect that the infection produces systemically.
MSOF
Is the end-stage of uncontrolled MODS.
6. Important Definitions
SIRS – Any 2
Hyperthermia (> 38°C) or Hypothermia (< 36°C)
Tachycardia (> 90/min) or Tachypnoea (> 20/min)
WBC > 12 × 10 99 / l or < 4 × 10 9 / l
SEPSIS
Is SIRS with a documented infection.
SEPSIS SYNDROME
Is sepsis with evidence of one or more organ failures.
9. Factors - Determine
Host response
Virulence
Vasculature & Health of tissue
Presence of dead / foreign tissue
Presence of antibiotic – “decisive
10. SSI – Assessment
For surgical wound assessment several scoring systems are employed
ASEPSIS wound score
Southampton wound grading system
These enable surgical wound healing to be graded according to specific
criteria, usually giving a numerical value, thus providing more objective
assessment of wound.
16. Depth - Deep Incisional SSI
Occurs - 30days – 1yr
Deep soft tissue
Purulent discharge – not from organ
Spont.opened or delibe.opened
Deep abscess – by re-op/histo/X-ray
Opened & diagnosed - surgeon
17.
18. Depth - Organ / Space SSI
Occurs - 30days – 1yr
Involves – any part [organ/space]
Purulent discharge – drain
Organisms – isolated
Deep abscess – direct & re-op /
histology / X-ray
Opened & diagnosed - surgeon
19.
20. Further classification
Etiology
Time Severity
Primary:
Acquired from a community
or endogenous source (such as
that following a perforated peptic
ulcer).
Secondary or exogenous
(HCAI): Acquired from the OT
(such as inadequate air filtration)
or Ward (e.g. poor hand-washing
compliance) or from contam. at or
after surgery ( anastomotic leak ).
Early
Infection presents
within 30 days of
procedure.
Intermediate
Occurs between 1 –
3 months.
Late
Presents > 3
months after surgery.
Minor
Wound infections may discharge pus
or infected serous fluid but should not
be associated with excessive
discomfort, systemic signs or delay in
return home.
Major
A major SSI is defined as a wound
that either discharges significant
quantities of pus spontaneously or
needs a secondary procedure to drain it.
21.
22. Surgical site prevention
Antibiotics & Prophylaxis
appropriately
Operation Theatre
procedures
Maintain normal
BG / BT
Post- op care
Pre- operative measures
23. Pre-operative
Staff should always wash their hands - pts.
Length of patient stay should be kept to a min.
Preop. shaving should be avoided if possible.
Antiseptic skin prepn. should be standardized.
Attention to theatre technique & discipline.
Avoid hypothermia perioperatively & ensure
supplemental O2 in recovery.
25. Principles – Antibiotic therapy
Antibiotics do not replace
surgical drainage of
infection.
Only spreading infection or
signs of systemic infection
justifies the use of
antibiotics.
26. Antibiotic therapy - Approach
A narrow-spectrum antibiotic may be
used to treat a known sensitive infection.
Combinations of broad-spectrum
antibiotics can be used when the
organism is not known or when it is
suspected that several bacteria, acting in
synergy, may be responsible for the
infection.
New antibiotics should be used with
caution & wherever possible, sensitivities
should first be obtained.
27. Prophylaxis – Choice of antibiotics
Empirical cover against expected pathogens
with local hospital guidelines.
Single-shot I. V administration at induction of
anaesthesia.
Repeat only in prosthetic surgery, long
operations or if there is excessive blood loss.
Continue as therapy if there is unexpected
contamination.
Pts. with heart valve disease or a prosthesis
should be protected from bacteraemia caused by
dental work, urethral instrumentation or visceral
surgery.
28. Regimes – Operations
Type of Surgery Organisms involved Prophylactic regime
Vascular Staphylococcus epidermidis (or
MRCNS)
Staphylococcus aureus (or MRSA)
Aerobic Gram-negative bacilli (AGNB)
3 doses of flucloxacillin with or without
gentamicin, vancomycin or rifampicin
if MRCNS / MRSA a risk
Orthopedic Staphylococcus epidermidis / aureus 1 -3 doses of a broad-spectrum
cephalosporin or gentamicin
Oesophagogastric Enterobacteriaceae / Enterococci 1 3 doses of a second-generation
cephalosporin & metronidazole in
severe contamination
Biliary Enterobacteriaceae / Enterococci 1 dose of a second-generation
cephalosporin
Small bowel Enterobacteriaceae / Anaerobes 1 – 3 doses of a second-generation
cephalosporin with or without
metronidazole
Appendix / Colorectal Enterobacteriaceae / Anaerobes 3 doses of a second-generation
cephalosporin (or gentamicin)
with metronidazole
29. Treatment
Mgt - depend on type of SSI
Surgical debridement of wound
Suture – removed – free drainage
Fluid – C/S – Suitable antibiotics
Signs of healing – sec. suturing
31. “Attack the problem, not the Person”
Penicillins- Penicillin G, Piperacillin
Penicillins with β-lactamase
inhibitors- Tazocin
Cephalosporins (I, II, III)-
Cephalexin, Cefuroxime, Ceftriaxone
Carbapenems- Imipenem, Meropenem
Aminoglycosides- Gentamycin,
Amikacin
Fluoroquinolones- Ciprofloxacin
Glycopeptides- Vancomycin
Macrolides- Erythromycin,
Clarithromycin
Tetracyclines- Minocycline,
Doxycycline
Editor's Notes
Inoculation of the surgical sites occurs during surgery either inward from the skin or outward from the internal organ being operated upon, the microbiology of SSI depends on the type of operation being performed .
Most SSI are caused by gram positive bacteria , organisms are part are skin derived. Increased likelihood of infection by gram negative bacilli after gastrointestinal surgery.
With surgery of the head and neck when pharyngeoesophygeal structure are opened anaerobic bacteria may cause SSI