[UPDATED] SURGICAL SITE INFECTIONS

An infection that occurs after surgery in the part of the body where the surgery took place

What is the Centers for Disease Control and Prevention (CDC) definition of a Surgical Site Infection (SSI)?

20%

SSIs account for what percentage of all hospital-acquired infections (HAIs)?

The most common and costly

SSIs are characterized as the most what among all hospital-acquired infections?

2% to 4%

SSIs occur in what percentage of all patients undergoing surgical procedures?

Prolonged hospital stays, additional surgeries/procedures, increased patient discomfort, increased healthcare costs, long-term disabilities, and death

Name four complications that SSIs may lead to.

60%

What percentage of SSIs are preventable with evidence-based guidelines?

Quality metrics

SSIs are used by TMC as one of the what to assess the quality of surgical care given to patients?

Superficial incisional

Which SSI classification involves only the skin and subcutaneous tissue of the incision?

Within 30 days following the procedure

For Superficial Incisional SSI, how long after the procedure does the infection occur?

More than 50%

What percentage of SSIs are typically accounted for by Superficial Incisional SSIs?

Purulent drainage from the superficial incision

What is one key sign that must be present, or the wound must be culture-positive/deliberately opened with localized symptoms, for a Superficial Incisional SSI diagnosis?

Culture is not mandatory but ideal

Is culture mandatory for diagnosing a Superficial Incisional SSI if the wound is deliberately opened?

Deep incisional

Which SSI classification occurs in deep soft tissues such as the fascia and muscle?

Fascia and muscle

Deep incisional SSIs occur in what two types of deep soft tissues?

Within 30 days following the procedure or within 1 year if implant is in place

What are the timeframes for when a Deep Incisional SSI must occur?

Spontaneously dehisces

What term describes a wound that opens by itself, relevant to Deep Incisional SSI criteria?

Fever (>38°C) or localized pain or tenderness

If a deep incision is opened or dehisces and is not cultured, what signs or symptoms must the patient have for it to be considered a Deep Incisional SSI?

Abscess or other evidence of infection detected on gross anatomical exam, histopathologic exam, or imaging test

What specific finding detected by imaging or examination can confirm a Deep Incisional SSI?

Organ/space

Which SSI classification involves any part of the organs and/or spaces other than the incision that was opened or manipulated during surgery?

Purulent drainage from a drain placed into the organ/space

What is one key diagnostic criterion for Organ/Space SSI related to drains?

Obesity

What host factor increases SSI risk due to poor blood circulation in adipose tissue, increased skin bacterial load, and potential for increased tension on the wound?

Weight management strategies

What can be implemented for elective surgeries prior to operation for obese patients?

Diabetes Mellitus

Patients with poorly controlled what are more susceptible to infections due to impaired immune response and reduced blood flow to the wound?

High blood sugar will reduce blood flow to the wound

Why does hyperglycemia slow down wound healing?

Strict perioperative glucose control

What is necessary for diabetic patients to manage SSI risk?

HbA1C test

What blood test measures average blood glucose over the past 2 or 3 months?

Nicotine

What component of smoking is a vasoconstrictor, reducing oxygen supply and impairing immune function?

Minimum of 4 weeks

How long before surgery should smokers be advised to quit smoking to significantly reduce the risk of wound complications?

50%

Quitting smoking a minimum of 4 weeks before surgery reduces wound complications by as much as what percentage?

Immunosuppression

What condition refers to immunocompromised patients who are vulnerable to infection due to weakened immune systems?

HIV, AIDS, Cancer, and uses of immunosuppressive drugs like steroids

Name three examples of causes of immunosuppression that increase SSI risk.

A more aggressive and a longer course

What adjustment might immunocompromised patients require regarding antibiotic prophylaxis?

Low serum albumin levels

Poor nutritional status, particularly when what is low, can disrupt immune function and impair wound healing?

Pre-operative nutritional assessment and support

What measures are important for managing malnutrition risk before surgery?

The presence of comorbidities and decline in body parts/immune function

Name two factors associated with advanced age that increase the risk of SSI.

Existing infection

What host factor, even if remote from the surgical site (like a UTI), can cause bacteremia and affect the surgery?

Treat and resolve existing infections before the operation

What action is required if a patient has an existing infection before surgery?

Peripheral vascular disease (PVD), Peripheral arterial disease (PAD), or Peripheral arterial occlusive disease (PAOD)

What three names refer to conditions involving poor circulation that can lead to ischemia and impaired healing?

Prolonged operative duration (>2 hrs)

What procedure-related factor increases the risk of SSI?

13%

A 15-minute increase in operative time raises the risk of SSI by what percentage?

Wound classification by level of bacterial contamination

What predicts the risk of SSI based on the assessment of bacterial load?

Class I - Clean

What is the AORN classification name for wounds that are not infected or inflamed and where no hollow viscus containing microbes is entered?

No hollow viscus containing microbes is entered

What crucial anatomical consideration determines a wound is Class I Clean?

Class I - D (Device)

Which special category of Class I involves the use of a prosthetic device?

Herniorrhaphy (mesh), Cardiac surgery (VAD), Hip or knee arthroplasty, Breast implant surgery

Name three examples of Class I - D surgeries.

Class II - Clean-contaminated

What is the AORN classification name for wounds involving controlled entry into the respiratory, alimentary, or genitourinary tract?

Medical bowel preparation

What preparation done before colon surgery helps classify the wound as Class II?

Class III - Contaminated wounds

What is the AORN classification name for wounds where skin integrity has been violated or gross contamination is present?

A major break in sterile technique during the procedure

Besides traumatic wounds or spillage, what factor can classify a wound as Class III?

Acute, non-purulent inflammation

What condition may be seen in Class III wounds?

Class IV - Dirty Wounds

What is the AORN classification name for traumatic wounds with a significant delay in management, resulting in necrotic tissue or purulent material?

Medical implants, devices, and drains

Name three types of foreign materials whose use increases the risk of SSI.

Biofilm

Communities of bacteria that form a protective layer, often on surgical implants or sutures, making SSIs difficult to treat.

Extracellular Polymeric Substances

What forms the structural matrix of a biofilm?

Suppress local immune cells (e.g., phagocytes)

The presence of an implant triggers a foreign body reaction that does what to the immune system locally?

100,000 organisms per gram of tissue

What is the normal bacterial load threshold required for infection to occur?

100 bacteria

With an implant, the bacterial load threshold for infection drops to as low as what number?

Prevent fluid buildup (hematoma or seroma)

What is the primary purpose of surgical drains?

The longer the drain stays in place

What factor increases the risk of infection related to drains?

Poor hand hygiene

What violation of aseptic technique involves improper preparation before any surgical procedure?

Hand rubbing with antimicrobial solutions

What is the current preferred method for surgical hand preparation, rather than hand scrubbing?

Cause microabrations on the skin and reused brushes may harbor microorganisms

Why are brushes discouraged in surgical preparation?

Use antimicrobial hand rub and scrub distal to proximal, covering fingers to elbows for at least 4 minutes

What is the current practice for surgical hand preparation?

Caps and masks

Which items of PPE are considered clean but not sterile?

Gowns and gloves

Which items of PPE must be sterile?

Leaving OR doors open or excessive foot traffic

Name two common issues related to poor environmental controls in the OR.

Touching non-sterile surfaces with sterile gloves

Give an example of a breach of sterile contact guidelines.

Virulence

What is the ability of an organism to establish an infection called?

Invasion factors, adherence factors, toxins (exotoxins/endotoxins), capsules, and antibiotic resistance

Name three microbial virulence factors.

Pili and fimbriae

Examples of adherence factors that allow bacteria to attach to and colonize tissues.

Exotoxins

Which type of toxin is mostly found in Gram-positive bacteria and is secreted to damage cells and tissues?

Endotoxins (LPS)

Which type of toxin is found in the outer membrane of all Gram-negative bacteria and is released when the cell is destroyed, causing fever and shock?

Capsules

What microbial factor is anti-phagocytic?

Staphylococcus aureus

What is the leading cause of SSIs overall, especially in cardiac, orthopedic, and vascular surgeries?

Coagulase-negative staphylococci (e.g., Staphylococcus epidermidis)

Gram-positive bacteria common in clean surgical cases involving implants or catheters.

Enterococcus species

Gram-positive bacteria, part of normal gut flora, frequently causing infections following abdominal and pelvic surgery.

Escherichia coli (E. coli)

Common gut bacterium, frequent cause of SSIs following gastrointestinal and abdominal procedures.

Pseudomonas aeruginosa

Gram-negative bacteria found in moist environments, known cause of healthcare-associated infections.

Bacteroides fragilis

An anaerobic, opportunistic Gram-negative pathogen common in abdominal and colorectal surgeries.

Klebsiella pneumoniae

Gram-negative bacteria, part of gut flora, particularly involved in abdominal surgeries.

Acinetobacter

Gram-negative organism found commonly in hospital settings, highly resistant to multiple antibiotics, often implicated in hospital outbreaks.

Anaerobes

Other potential pathogens commonly involved following head and neck or abdominal surgery.

Fungal pathogens (e.g., Candida)

Less common potential pathogens that may appear in immunocompromised or hospitalized patients.

Gram-positive organisms (e.g., Staphylococcus aureus)

What class of pathogens is typically associated with Cardiac, Orthopedic, and Vascular Surgery?

Gram-negative organisms (e.g., E. coli, Klebsiella) and anaerobes

What classes of pathogens are typically associated with Abdominal and Colorectal Surgery?

Combination of Staphylococcus aureus and Escherichia coli

What combination of pathogens is typically associated with Urological Surgery?

To bathe or shower prior to surgery

What is good clinical practice to ask patients to do pre-op?

Mupirocin

What drug should be applied if the patient is a known nasal carrier of Staphylococcus aureus?

Within 120 minutes before incision (most commonly 30 minutes)

What is the optimal timing for administering pre-op surgical antibiotic prophylaxis?

Elective colon surgeries

Mechanical bowel preparation and the use of oral antibiotics are specifically used in preparation for what type of procedure?

Clipper, immediately before surgery

If hair removal is necessary, what tool should be used, and when should it be done?

Shaving

What hair removal method is strongly discouraged due to the risk of micro-cuts?

Alcohol-based antiseptic, preferably containing chlorhexidine gluconate

What is the recommended product for surgical site preparation?

Oral or enteral multiple nutrient-enhanced formulas

What should be administered to undernourished or malnourished patients to provide enhanced nutritional support?

The time of incision

Prophylactic antibiotics must be at a high dose in the circulatory system at what specific moment to be effective?

Class II (clean-contaminated) and Class III (contaminated)

For which two wound classes are prophylactic antibiotics recommended?

Class ID (device-related)

For which subcategory of Class I wounds are prophylactic antibiotics indicated?

Therapeutic treatment

Antibiotic use for Class IV (dirty) wounds is considered what type of treatment?

High risk of infection or High National Nosocomial Infections Surveillance (NNIS) risk index

Name two criteria for administering preventive antibiotics.

Surgery duration, wound class, and ASA (American Society of Anesthesiologists) score

What three factors determine the NNIS risk index?