Surgical site infection (SSI) is one of the most common and costly hospital-acquired infections. Risk factors include patient characteristics like diabetes, obesity, and environmental factors such as inadequate sterilization. SSIs are classified as superficial, deep, or organ/space based on the tissue layers involved. Prevention strategies focus on pre-operative patient preparation, strict sterile techniques during surgery, and post-operative wound care and antibiotics when needed. Proper treatment requires identifying the pathogen, controlling the infection source, administering empiric antibiotics, and timely de-escalation.
2. Introduction
Most common and costly of all hospital acquired infections
Associated with increased length of stay and 2-11 times
increase in the risk of mortality
About 60% of SSIs are preventable with evidence-based
guidelines
SSIs must occur within 30 days after the operative
procedure if no implant is left in place, or within 1 year if
implant is in place, and the infection appears to be
related to the operative procedure
Overall, S aureus is the most common SSI pathogen
5. Treatment factors
Blood transfusion
contamination : poor scrubbing technique, breach in
asepsis, poor gloving, etc.
Drains
Emergency surgery
High wound classification
Hypothermia
Hypoxemia
Inadequate or inappropriate antibiotic prophylaxis
Poor glycemic control
Prolonged operation
6. Classification of surgical site infection
SSIs are classified based on the depth and tissue layers involved as
superficial incisional, deep incisional and organ/space
DEFINITIONS
Superficial incisional SSI (SIS) :within 30 days and only skin and
subcutaneous tissue of the incision involved and had at least one of
the following:
purulent discharge from the superficial incision
Organisms isolation from incision(aseptically)
Signs or symptoms of infection(at least one): pain or tenderness,
localized swelling , redness , or heat and superficial incision is
deliberately opened by surgeon and is culture positive or non
cultured. A culture negative finding does not meet this criterion
Diagnosis of superficial incision SSI by the surgeon
7. Deep incisional surgical site infection
infection occurs within 30 days after the post operation if no implant
or within one year if implant present. And infection appears to be
related to operative procedures involving deep soft tissues example
facial and muscular plane of the incision and patient has at least one
of the following:
1. Purulent drainage from deep incision
2. Deep spontaneously dehisces or is deliberately opened by surgeon
with culture positive or non cultured when the patient has at least
one of the following signs or symptoms fever >38oC or localized
pain or tenderness
3. And abscess or infection involving deep incision found on direct
examination, reoperation, histopathological or radiological
examination
4. Diagnosis of deep SSI by a surgeon
8. ORGAN OR SPACE SSI
Here SSI involving any part of body excluding the earlier
layers with at least one of the follwings:
1. Purulent discharge from a drain that is placed through
stab wound into the organ/space
2. Organism isolated from fluid or tissue in the
organ/space
3. And abscess or other evidence of infection involving
the organ or space found on direct examination,
reoperation, histopathological or by radiological
examinations
4. Diagnosis of an organ/space SSI by a surgeon
9.
10.
11. Classification of surgical wounds
CATEGORY CRITERIA INFECTION RATE
WITH ANTIBIOTIC WITHOUT
PROPHYLAXIS PROPHYLAXIS
CLEAN No hollow viscus entered
Primary wound closure
No inflammation
No break in aseptic precaution
Elective procedure
1-2% 1-2%
CLEAN-CONTAMINATED Hollow viscus entered but controlled
No inflammation
Minor break in aseptic technique
Mechanical drain used
Bowel preparation preoperatively
3% 6-9%
CONTAMINATED Uncontrolled spillage from viscus
Inflammation apparent
Open,traumatic wound
Major break in aseptic technique
6% 13-20%
DIRTY Untreated, uncontrolled spillage from
viscus
Pus in operative wound
Open suppurative wound
Severe inflammation
7% 40%
12. TREATMENT STRATEGIES FOR SSI
Pathogen identification
Source control by opening the incision in superficial or deep surgical site
infections or by image guided percutaneous drainage, laproscopic, or open
drainage if indicated in organ/space SSI
Immediate empiric antibiotics coverage
Timely antibiotic de-escalation
Local wound care
13. PREVENTION
Patients should shower with soap the night before surgery
Hair removal from surgical site, clipper should be used
Skin preparation with alcohol based antiseptic solution example chlorhexidine before
incision
Preoperative glycemic control less than 200 mg/dl
Avoid preoperative hypothermia (Core temperature <36oC)
Use of increased FiO2 during general anesthesia and for 2-6 hrs postoperatively
Use of sterile surgical instrument
Antimicrobial coated suture material usage
Topical NPWT for managing open wounds
Pre operative antibiotic should be administered within 60 mins of skin incision
Redosing of antibiotics if surgery exceeds two half lives of the drug or with massive
blood loss
