Surgical Site Infections (SSI)

Definition

• Purulent discharge, abscess or spreading cellulitis at surgical site up to one month after surgery.

• Surgical site infection is the second most common complication following surgical procedures (first being postoperative pneumonia)

• 3rd most common hospital infection

Common Sources of Infection

• x Surgical wards: - wounds, ulcers, catheters, drains, sputum,

-urine, faeces, open wounds.

• x Operation room :

- Lack of proper ventilation .- nurses, surgeons.

- Operation methods , sterilisation of instruments.

Organisms Causing SSI

• x Commonly Staphylococcus aureus.

• Gram-negative bacteria .

• Clostridia

• colonization : Presence of Bacteria in a wound with no signs or symptoms of systemic inflammation .

• Contamination : Transient exposure of a wound to bacteria (usually less than 6 hours)

SSI transmission

• Exogenous

– Surgeons, nurses and other staff

– Medical equipment

– Other patients

• Endogenous

– Skin flora

– Other infections in patient

– Blood transfusion (rare)

SSI – Wound Classification

CleanClean

contaminated

Contaminated Dirty infected

Clean wounds : operative procedure does not enter into normally colonised viscus.

• Clean-contaminated: operation enters into a colonised viscus but under elective controlled circumstances

Contaminated wounds : gross contamination is present at the surgical site in the absence of obvious infection

•Dirty wounds : surgical procedures performed when active infection is present

Types of Surgery

Classification of Surgical Site Infection (SSI)According to the Depth of the Wound Infection

Deep incisional Organ space infection

Superficial incisional

- involves only skin and subcutaneous tissue; and one of following:Purulent drainage (culture documentation not required), organismsisolated from fluid/tissue of superficial incision, at least 1 sign of inflammation, wound is deliberately opened by the surgeon .

- involves deep soft tissues of the incision; and at least one of the following : purulent drainage from the deep incision site withoutorgan/space involvement, fascial dehiscence or deliberate separation by surgeon, deep abscess, identified by—reoperation/histopathology/radiology .

- Involves anatomic structures not opened or manipulated during surgery; and oneof the following : pus from a drain placed into organ/space, organism isolated by culture, identification of abscess by direct examination,reoperation, histopathology, radiology .

Risk FactorsHost Risk Factors

• Diabetes mellitus

• Hypoxaemia

• Hypothermia

• Leukopenia

• Nicotine (tobacco smoking)

• Immunosuppression

• Malnutrition

• Poor skin hygiene

Perioperative Risk Factors

• Operative site shaving

• Breaks in operative sterile technique

• Improper antimicrobial prophylaxis

• Prolonged hypotension

• Contaminated operating room

• Poor wound care postoperatively

• Hyperglycemia

• Wound closure technique

Management

Prevention of SSI• Preoperative• Preoperative cleaning and

antiseptic scrub of surgical site.

• Surgery should be avoided or postponed if fingers or hand of surgeon has open wounds or infection.

• Obvious infection in patient if exists should be treated.

• Prolonged preoperative admission should be avoided for an elective surgery.

• Care in the Operation Theatre

• sterile caps, masks, gowns and sterile

• gloves • Proper skin cleaning is needed

using antiseptics like povidoneiodine.

• Gentle tissue handling, absolute haemostasis, holding tissues using instruments as much as possible, using appropriate suture materials,

• avoiding dead space during closure

• One should consider leaving wounds open if it is severely contaminated.

Prevention of SSI

• Preventive Antibiotic Therapy

• Antibiotics should be administered as close to the incision time as

• possible, before induction of anaesthesia.

• Postoperative systemic antibiotics for 24 hours

• Oral antibiotic bowel preparation with appropriate mechanical bowel preparation

• Enhancement of Host Defences

• Increased oxygen delivery facilitates phagocytic eradication of microbes.

• Optimising core body temperature is important as warmer patients resist bacteria better.

• Blood glucose control is essential even to nondiabetics as well

Management

• SSI is managed depending on the type of SSI—superficial, deep or organ space.

• All infected material and pus should be removed from the wound site—debridement.

• Sutures are removed to allow free drainage of infected material.

• Infected fluid is sent for culture and sensitivity and suitable antibiotics are started.

• Once wound shows signs of healing by healthy granulation tissue, secondary suturing is done. Often it is allowed to heal by scarring.

Operative Antibiotic Prophylaxis

• Decreases bacterial counts at surgical site

• Given within 60 minutes prior to starting surgery (knife to skin)

• Repeat dose for longer surgery (T 1/2)

• Do not continue beyond 24 hours

• Determinants – prevailing pathogens, antibiotic resistance, type of surgery

• Not a substitute for aseptic surgery or good technique

Timing of prophylaxis

• Intravenous antibiotics should be given within 60 minutes before skin incision and as close to time of incision as practically possible

(N Engl J Med 1992;326:281-6 & Ann Surg 2008;247:918 - 926)

• For caesarian section it can be given pre-incision or after cord clamping

• Single dose with long-enough half-life to achieve activity for duration of operation

Preop

• Scrub

– Duration? With what?

• Skin preparation

– Iodophors, chlorahexadine, or alcohol

• Hair removal

– Night before? Clipper vs razor

• Antiseptic showering

– Reduce skin flora only

Surgical Site Infection Prevention Bundle Components

1. Prophylactic antibiotic given within one hour prior to surgical incision

2. Appropriate prophylactic antibiotic selection for surgical patients

3. Prophylactic antibiotics discontinued within 24 hours after surgery end time (48 hours for cardiac surgery)

4. Cardiac surgery patients with controlled 6 A.M. postoperative serum blood glucose

Surgical Site Infection Prevention Bundle Components

5. Surgery patients with appropriate hair removal

6. Surgery Patients with Perioperative Temperature Management – maintaining normothermia

7. Urinary Catheter removal on postoperative Day 1 or 2 with day of surgery being day zero.

Other SSI Prevention Measures*

• Protect closed incision with sterile

dressing for 24-48 hours

postoperatively

• Maintain adequate/recommended

ventilation processes in the

operating rooms

*CDC Guideline for Prevention of Surgical Site Infections, 1999

(WHO) Global guidelines• Patients with known nasal carriage of S. aureus should receive

perioperative intranasal applications of mupirocin 2% ointment with or without a combination of CHG body wash.

• MBP alone (without the administration of oral antibiotics) should NOT be used in adult patients undergoing elective colorectal surgery.

• In patients undergoing any surgical procedure, hair should either NOT be removed or, if absolutely necessary, should only be removed with a clipper. Shaving is strongly discouraged at all times, whether preoperatively or in the operating room.

• Surgical antibiotic prophylaxis (SAP) should be administeredbefore the surgical incision, when indicated.

• SAP should be administered within 120 min before incision, while considering the half-life of the antibiotic.

• Surgical hand preparation should be performed either by scrubbing with a suitable antimicrobial soap and water or using a suitable alcohol-based handrub before donning sterile gloves.

• Alcohol-based antiseptic solutions based on CHG for surgical site skin preparation should be used in patients undergoing surgical procedures.

• Adult patients undergoing general anaesthesiawith endotracheal intubation for surgical procedures should receive 80% fraction of inspired oxygen intraoperatively and, if feasible, in the immediate postoperative period for 2–6 h.

• Surgical antibiotic prophylaxis administration should not be prolonged after completion of the operation