Surgical site infections (SSIs) occur in the wound or deeper tissues after surgery. WHO reports that SSI is one of the most frequent healthcare-associated infections in low- and middle-income countries, affecting a significant proportion of surgical patients, and that caesarean section wound infections are a particular concern. SSIs cause pain, longer hospital stays, extra costs, wound breakdown and sometimes death. Many are preventable, and nurses play a key role before, during and after surgery.
Types of SSI
- Superficial incisional: skin and subcutaneous tissue.
- Deep incisional: muscle and fascia.
- Organ/space: for example, an abdominal abscess after bowel surgery or endometritis after caesarean.
Risk factors
- Patient: diabetes (especially poor glucose control), obesity, smoking, malnutrition, immunosuppression, existing infections.
- Surgery: emergency or long operations, contaminated procedures (bowel surgery), implants, poor technique.
- Environment: poor hand hygiene, inadequate sterilisation, overcrowded wards, lack of water.
Before surgery
- Bathing or showering with soap (plain or antimicrobial) before surgery.
- Don’t shave the site. If hair removal is necessary, use clippers. WHO recommends against razors because tiny cuts increase infection risk.
- Optimise blood glucose, nutrition and smoking cessation where time allows.
- Screen and decolonise for MRSA where policy requires (e.g. some cardiac and orthopaedic surgery).
- See our pre-operative preparation guide.
During surgery
- Antibiotic prophylaxis within 120 minutes before incision (when indicated), not prolonged after surgery. WHO advises against continuing prophylactic antibiotics after the operation to prevent SSI.
- Alcohol-based chlorhexidine skin preparation.
- Surgical hand preparation, sterile gowns, gloves and instruments.
- Maintaining normal temperature and adequate oxygenation.
- Use of the WHO Surgical Safety Checklist.
After surgery: wound care
- Keep the original dressing in place for the time advised (often about 48 hours) unless soaked or leaking.
- Hand hygiene before and after touching wounds; use aseptic non-touch technique (ANTT) for dressing changes.
- Use sterile saline or tap water (where safe) for wound cleaning as per local policy.
- Monitor blood glucose in diabetic patients.
- Encourage nutrition, hydration and mobility.
- Document wound appearance at each check. See our wound dressing guide.
Signs of infection
- Increasing redness spreading from the wound edges.
- Swelling, warmth, increasing pain or tenderness.
- Pus or cloudy, foul-smelling discharge.
- Wound edges separating (dehiscence).
- Fever, rising heart rate, feeling unwell. Watch for sepsis.
SSIs often appear 3–7 days after surgery, frequently after discharge, so patient education is vital.
If you suspect infection
- Escalate for medical review.
- Take a wound swab as advised (ideally before antibiotics).
- Mark the edge of spreading redness with a pen and time to track progression.
- Antibiotics, wound opening and drainage, or surgery may be needed.
Discharge education
- How to keep the wound clean and dry, and when they can shower.
- Hand washing before touching the wound.
- Don’t apply traditional remedies, powders or creams unless prescribed.
- Signs of infection and who to contact.
- When stitches or clips will be removed. See our suture and staple removal guide.
Based on WHO Global Guidelines for the Prevention of Surgical Site Infection and NICE NG125. Educational content: follow local policies.