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100 Surgical Site Infection
Complications Prevention
If uncontrolled, SSI may progress to life-threatening complications. Risks
The severity of each complication depends in large part on the infect- The risk of developing a surgical wound infection is largely deter-
ing pathogen, the site of infection, the nature of surgery, and the mined by three factors:
underlying host factors. Due to the frequently delayed presentation
of several conditions, and the high prevalence of SSI, complications 1. the amount and type of microbial contamination of the wound;
occur often in sub-Saharan Africa. 2. the condition of the wound at the end of the operation (largely
Commonly encountered early complications are necrotising determined by surgical technique and disease processes encountered
fasciitis, wound dehiscence, metastatic abscesses, and septicaemia and during the operation); and
organ failure. Delayed or long-term complications include incisional 3. host susceptibility, that is, the patient’s intrinsic ability to deal with
hernia and ugly and/or deforming scars. microbial contamination.
Investigations These factors interact in a complex manner to result in SSI.
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Although the diagnosis of most surgical site infection is clinical, Measures intended to prevent surgical wound infections are directed at
these. The preoperative hospital stay should be kept as short as possible.
further investigation may be necessary for planning of treatment and Any host factors likely to predispose to SSI, including nutritional issues,
follow-up. Any of the following investigations may be relevant: medications such as steroids, diabetic control, and remote infections
1. Any discharge from the wound should be cultured to establish should be properly controlled before embarking on surgery.
the microbiological profile and organism antibiotic sensitivity of the
infection. Tissue biopsy and culture may be helpful in situations where Prophylactic Antibiotics
culture of discharge proves contaminated or unable to provide a reliable Prophylactic antibiotics are those administered to patients before
yield. The culture should involve both aerobic and anaerobic culture. contamination has occurred. Their role is to minimise postoperative
2. Ultrasonography may be required if subcutaneous or organ infection in clean or clean-contaminated wounds. The choice and
space collection is suspected; however, if used too early, this modality use of prophylactic antibiotics should be guided by the knowledge of
may give false positives, as fluid may just be postoperative serous site-specific flora (both patient and hospital environment), as well as
collections rather than pus. It is also useful in monitoring treatment. the nature of the intended surgery, the antibiotic spectrum of cover,
3. A computed tomography (CT) scan is rarely necessary but may toxicity, and pharmacokinetics, with the aim being the highest tissue
be helpful in organ space infection, specifically where multiple relook levels at the time of maximum contamination. If no hollow viscus or
laparotomies and bowel gas distort any ultrasound view or when mucosal barrier is violated, antibiotics generally need to cover only
ultrasonography does not provide conclusive information. gram-positive organisms, whereas breach of the gastrointestinal, geni-
4. A complete blood count will determine whether leucocytosis tourinary, biliary, and aerodigestive tracts should cover both skin flora
and neutrophilia are evident, especially when the infection becomes and site-specific aerobic and anaerobic organisms, if needed.
systemic. Antibiotics should be given parenterally. The first dose should be
5. In persistent/uncontrollable situations, efforts should be made given not more than 2 hours before the skin incision and is frequently
to identify any underlying predisposing factors such as HIV infection, given at the time of anaesthetic induction. Infection risk is higher in
diabetes mellitus, foreign bodies, or anastomotic breakdown and fistula procedures lasting more than 2 hours, so antibiotic repetition may be
formation. required. It must be emphasized that prophylactic antibiotics should
Management not be a substitute for adherence to strict asepsis in the operating room
and meticulous surgical technique.
Specific Treatment Operating Environment
The definitive treatment of SSI is adequate pus drainage. The entire
wound must be opened by suture removal for effective drainage. In The operating team should adhere to a tested scrub protocol using reli-
incisional SSI, the wound is packed with moist gauze or commercial able antiseptics. The surgical site should be prepared by using potent
cavity dressing until granulation has appeared. Dressing with native and reliable antiseptics appropriate to the site. Every effort should be
honey has been proven efficient in Africa. 14,20 Depending on circum- made to avoid breaking aseptic techniques during the entire procedure.
stances, secondary suture of granulating clean wounds may be possi- Most infections are acquired in the operating room, so good
ble. Vacuum-assisted dressings have been clinically proven to encour- surgical practices are crucial to their prevention. Excellent surgical
age granulation tissue and wound closure, and in the African setting, technique is widely believed to reduce the risk of SSI. This includes
the use of wall suction on low pressure suction is perfectly acceptable maintaining effective haemostasis while preserving adequate blood
to achieve adequate vacuum-assisted closure (VAC) dressing. supply, preventing hypothermia, gently handling tissues, avoiding
Even though percutaneous ultrasound-guided drainage may be inadvertent entries into a hollow viscus, removing devitalised tissues,
possible in organ space collections, surgical drainage is often required using suture material appropriately, eradicating dead space, and
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to remove all collected pus and any dead tissue or slough, and to appropriately managing the postoperative incision.
irrigate the cavity. Surveillance
General Measures The development of an SSI surveillance programme within each unit
In most instances, local wound care, as detailed above, may be enough or hospital is essential for recognition and reduction of surgical wound
to control the infection. However, if there are systemic features or the infections. 22–24 Further research is needed to determine the most practi-
infection is not controlled by local measures, then empiric systemic cal and sensitive method for general use. Inpatient surveillance must
antibiotics, altered when sensitivities become available, should be include bedside examination and total chart review, which has a 90%
24
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given. Failure of response within 48–72 hours may suggest underlying sensitivity, and microbiology report review (sensitivity 33–65%).
deeper abscess requiring drainage or wound exploration for gangre- One infection control nurse for a total of 250 beds, together with an
1
nous complications. organised surveillance system, can reduce hospital infection rates by
up to 32%. 22