Surgical Site Infection Prevention

Age

Elderly patients suffer more from health conditions, illnesses and severe disorders, and they have a decreased immune response to infection.
Furthermore, older patients who develop SSIs have greater morbidity and mortality compared to younger patients.²

Age is not a modifiable factor, so it is important to examine older patients preoperatively. You should define their level of health and identify potential risk factors before the surgery.

Nutritional State

Malnutrition can decrease immune function and contribute to poor wound healing, both of which increase susceptibility to infection.

If a patient is found to be malnourished preoperatively, appropriate interventions should be planned to improve the patient’s nutritional status before the surgery.³

Obesity

Obesity-related immune disorders decrease immune response and can lead to diabetes.

Respiratory and pharmacologic issues related to obesity can also contribute to increased susceptibility to SSIs.⁴ It is important to assess the body mass index (BMI) of obese patients preoperatively and encourage weight loss and proper nutrition prior to surgery.

Diabetes Mellitus and Hyperglycaemia

Studies have shown that both insulin-dependent and non-insulin-dependent diabetic patients are at an increased risk for developing SSIs.⁵ This is due to poor immune function and delayed wound healing.

Diabetic patients need to have controlled blood glucose levels preoperatively, intraoperatively and postoperatively. Patients should receive insulin perioperatively to control hyperglycaemia and minimise the risk of adverse outcomes.⁶

Bacterial Colonisation and Coexisting Infections

Research shows that surgical sites containing more than 100,000 microorganisms per gram of tissue have a significantly greater risk of infection.

However, it is important to note that the number of microorganisms necessary to cause an infection is significantly lower when there is foreign material, such as surgical mesh, at the site.⁷

If a patient has an existing infection at the time of surgery, this also increases the likelihood of developing an SSI.¹

Smoking and Nicotine Use

Smoking reduces oxygen delivery to tissues, damaging wound healing abilities and immune defences.

Quitting cigarettes before the surgery can help increase oxygenation to the tissues, improve healing and reduce the risk of SSIs. Receiving additional oxygen perioperatively can also help improve tissue oxygenation and reduce the SSI risk.⁸

Immunosuppression

Any medical conditions or medications that cause immunosuppression will increase the risk of SSIs, in particular, steroids that have been linked with postoperative complications.⁹

Antimicrobial Prophylaxis

If prophylactic antibiotics are needed, they should be administered within one hour before the surgery and stopped within 24 hours afterwards. Continued use of antibiotics to treat a specific infection are the exception to this rule.²

Preoperative Hair Removal

Shaving is ill-suited for this task because it can result in multiple skin abrasions, which can later become infected.² Hair should only be removed if it is interfering with the operation by using clippers or a depilatory agent.

Preoperative Skin Preparation and Antisepsis

The goal of preoperative skin preparation and antisepsis is to clean the skin and remove microorganisms, reducing the SSI risk.³ The Association of periOperative Registered Nurses (AORN) recommends that patients should shower prior to surgery with either soap or an antiseptic.³

Multidisciplinary teams, including perioperative nurses, physicians and infection prevention specialists, should select safe and effective products for skin antisepsis. The solution used for each patient and each procedure should meet the regulations in place and be appropriate for the patient’s needs in terms of allergies or sensitivities.³

Prior to applying the antiseptic preparation solution to the patient’s skin, the nurse should verify that the skin is free of:

• Soil
• Debris
• Emollients
• Cosmetics
• Alcohol-based products.

Nurses should perform hand hygiene, don sterile gloves and use sterile techniques while applying the skin antiseptic. Once the skin has been prepared, only sterile items should be exposed to the skin.³

Sterile Attire

Personnel in the perioperative area should comply with appropriate guidelines for sterile attire to minimise the patient’s exposure to microorganisms. AORN provides best-practice recommendations for surgical attire:

1. Clean surgical attire should be worn in the semi-restricted and restricted areas of the perioperative setting.
2. All individuals who enter the semi-restricted and restricted areas should wear disposable scrub attire or scrub attire laundered at a healthcare-accredited laundry facility.
3. Personnel entering the semi-restricted and restricted areas should cover their head, hair, ears and facial hair.

Surgical Technique

The surgical technique refers to numerous activities performed during the surgery. Surgical technique can vary widely depending on the surgeon and can greatly influence the development of SSIs. Here are a few techniques that can help minimise the risk of infections:

• Achieving adequate haemostasis while simultaneously preserving blood supply to the tissues
• Handling tissues gently
• Avoiding inadvertent perforation of a hollow viscus, such as the stomach
• Removing devitalised tissues that are charred or necrotic
• Properly using drains and suture material and minimising dead space
• Preventing intraoperative hypothermia.¹

Foreign Material in the Surgical Site

Foreign materials within the surgical site present a breeding ground for infection.

There is a wide variety of foreign materials, ranging from suture material and surgical mesh to prostheses. They can promote inflammation and bacteria can grow on them.¹

Surgical Drains

Surgical drains can potentially increase a patient’s risk of an SSI, particularly if the drains are not handled properly.

When drains are used during a surgery, the likelihood that an SSI will develop is higher. Drains should be placed through a separate incision distant from the surgical incision site.

Additionally, studies have shown that when closed suction drains are used rather than open ones, the incidence of SSI is reduced. The utilisation of drains can be important after the operation and can help effectively evacuate hematomas or seromas.

However, it is important to keep in mind that the timing of drain removal can affect infection rates. Bacterial colonisation of the drain tract will increase the longer the drain is left in place.¹

Instrument Sterilisation

Inadequate instrument sterilisation has been associated with SSI outbreaks. It is therefore important to understand the different methods of sterilisation and the guidelines in place in order to ensure the efficacy of the sterilisation process.

There are different methods of sterilisation:

• Steam under pressure
• Dry heat
• Ethylene oxide
• Gamma radiation.¹

Perioperative Hypothermia

Many studies have shown that patients who are hypothermic in the perioperative period have increased rates of postoperative complications, including SSIs.

Hypothermia is defined as a core body temperature of less than or equal to 36^o Celsius. In the cold operating theatre environment, blood is pushed away from the skin into the core of the body to protect vital organs. This results in decreased perfusion and oxygenation of the skin. Blood vessels in the skin also undergo vasoconstriction, further reducing blood flow.

Furthermore, when the body temperature is low, cellular consumption of oxygen is reduced. This impairs the natural defences within the skin from being able to fight off infectious organisms.³

Adherence to Sterile Technique

The sterile technique process prevents contamination and allows for maintaining a sterile field during procedures. The sterile technique includes:

• Wearing clean scrub attire (including appropriate head and feet coverings)
• Following hand hygiene practices
• Wearing a clean mask for each procedure.

A well-maintained sterile field can influence patient outcomes and reduce infection rates.²

Oxygenation

Adequate oxygen supply to tissues is essential for wound healing and infection prevention. Oxidative killing, or destruction by oxidation, is the most important mode of defence against pathogenic organisms. This process is dependent upon the partial pressure of oxygen in the tissue.⁴

Operating Theatre Ventilation

The air in the operating theatre may contain dust, lint, skin squames or respiratory droplets, which are laden with microorganisms. The number of microbes in the air is related to the traffic in and out of the operating theatre; therefore, traffic should be limited.

Additionally, operating theatres should maintain positive pressure compared to adjacent areas. This prevents airflow from the adjacent areas, which are presumably less clean, into the operating theatre.¹

Length and Type of Operation

Both the length and type of procedure can affect the patient’s risk of developing an SSI.

Longer procedures are associated with a higher SSI risk, and procedures have varying levels of contamination, which directly affect SSI risk.

Types of Wound Closure

Postoperative wound care can vary greatly depending on the type of wound and how it is closed:

• Primary closure describes fully closing the surgical wound in the operating theatre, with either staples or sutures.
• Secondary closure happens when the wound edges are not initially approximated in the operating theatre. Granulation tissue gradually fills in the wound defect, healing the wound.
• Delayed primary closure happens when the surgical wound is left open following the surgery, but is then closed after a few days of observation if no infection is present.

Both secondary closure and delayed primary closure are used when the wound is thought to be contaminated.²

Incision Care

Wound care depends on the wound and closure type.

Most surgical wounds are closed primarily. These wounds are typically covered with a sterile dressing for 24 to 48 hours. This allows epithelialisation of the wound to occur for protection against infectious external pathogens. After this period, dressings can be quite variable depending on the condition of the wound and if drainage is necessary.

When delayed primary closure or secondary closure techniques are used, the wound is packed with sterile gauze and is then covered with a sterile dressing. As the wound is likely contaminated, it should be left open, as to not trap the bacteria. These wounds should be closely monitored for signs of infection.¹

Length of Hospital Stay

An extended hospital stay increases the risk of SSIs.

The longer patients are hospitalised, the more exposure they have to bacteria, particularly antibiotic-resistant bacteria.¹

Discharge Planning and Instructions

Patients are often discharged before their wounds have fully healed. Thus, it is important for nurses or other healthcare professionals to give the patient and their family the appropriate wound care instructions. Patients should also be encouraged to contact their surgical team with any questions.¹