Introduction

Wound bed preparation is vital to treating biofilm. Resistant to antibiotic treatment, biofilm not only stalls the healing process of chronic wounds but also puts patients at greater risk for amputation. Clinicians should follow the process of successful wound healing described in the TIMERS framework (Tissue, Inflammation/infection, Moisture imbalance, Epithelial edge advancement, Repair/regeneration, and Social factors) to guide wound care.¹ Proper wound bed preparation recognizes that biofilm prevention and treatment in chronic wounds incorporate aggressive wound debridement to suppress biofilm regrowth, disrupt the bacterial burden, and promote a healthy wound bed environment.²

Biofilm treatment is a multifaceted, holistic process because of the complex nature of biofilm and its resistance to traditional antibiotic interventions. Given biofilm’s ability to resist host immunities and its tolerance to antibiotic treatment, clinicians should remain vigilant for biofilm during wound assessment practices.

Patient Risk Factors

All patients should undergo a risk assessment during their first clinic visit, home visit, or hospital admittance. Check for the risk of pressure injury development, infection, or amputation, among other conditions. Usually because of the presence of comorbidities or immunosuppressive medications, some patients may be deemed more susceptible to infection and amputation than others. These high-risk patients should receive extra care to ensure prevention of infection and amputation.

Clinicians should make sure that the increased risk is noted in the patient’s chart or file so that appropriate steps are taken at every stage of care to promote best outcomes for the patient. Systems that utilize electronic medical records are especially helpful with this documentation because the file can typically be accessed by multiple clinicians in multiple locations, thus ensuring that proper interventions are put in place.

Biofilm Prevention and Treatment Overview

Wound bed preparation promotes holistic, patient-centered care that adjusts the interaction of the biofilm or infectious pathogens by optimizing the host response, reducing the number of microorganisms, and improving the wound healing environment. Regular assessment and wound bed preparation will promote an ideal healing environment, thus minimizing factors that increase infection risk (biofilm). The following list details methods of prevention and treatment of biofilm formation.

• Evaluate the intervention plan based on signs and symptoms of wound infection and overall patient condition: Has pain increased or decreased? Is there been an increase in nonviable tissue? Is the wound expanding?
• Manage comorbidities.
• Monitor nutrition and hydration.
• Treat systemic symptoms (eg, pyrexia, pain).
• Provide antimicrobial therapy as appropriately indicated.
• Communicate treatment plans clearly with the patient, and ensure that the patient is an active participant in recovery and treatment (avoid medical terminology).

Microbial Load Prevention

It is essential to minimize the microbial load within a wound. If methods of prevention are implemented, inflammation should decrease.

• Prevent cross-contamination and infection by using precautions and aseptic technique.
• Promote best practices for periwound hygiene and protection.
• Manage exudate, thus minimizing inflammatory response.
• Remove necrotic tissue, foreign debris, dressing remnants, and slough.

Microbial Load Reduction Treatments

If a significant microbial load has formed despite prevention methods, implement aggressive treatment that removes biofilm and manages moisture levels.

• Properly cleanse wound at each dressing change and after debridement.
• Perform debridement to disrupt biofilm.
• Assess the wound, and use the appropriate dressing to manage moisture levels and inhibit biofilm reformation.

Debridement

Debridement is one of the most effective treatment strategies used against biofilm. However, it does not remove all biofilm and therefore cannot be used alone—this is one of the critical principles of wound bed preparation. Debridement of slough, necrotic, and other nonviable tissues is essential to allow the healing process to restart. An aggressive approach to address bioburden should begin with a method of wound debridement that will help control biofilm, suppress biofilm regrowth, disrupt the microbial burden, and promote wound healing.² Although there are no set guidelines for the frequency of debridement, studies have shown that wounds healed 83% of the time in those centers that debrided wounds weekly.³ In sporadically debrided wounds, however, only 25% of the wounds healed.³

When deciding on a debridement method, consideration needs to be given to patient factors, wound appearance, environmental factors, and clinician confidence and knowledge. Assessment of the wound before debridement is essential. Clinicians should assess for rolled edges of the wound or other areas where bacteria can harbor and grow. Assessment for and removal of slough and necrotic tissue will ensure that bacteria do not have a source of nutrients on which to feed and grow. Further, some debridement methods are not as effective at removing biofilm as others. Autolytic debridement is slow and requires an active patient immune system. It is not an ideal method for biofilm removal or prevention, nor is enzymatic debridement, for similar reasons. Although debridement effectively disrupts biofilm attachment, it will not extirpate biofilm presence.

Once debridement is complete, a combination of therapeutic cleansing with topical antiseptics and antimicrobial dressings should be used to take advantage of the window where bacteria are most susceptible to antimicrobials. Selected dressings should also promote good moisture balance, absorbing excess exudate without drying out the wound bed.

Cleansing

Following wound bed preparation procedures, debridement encourages an optimal environment to disrupt biofilm, thereby allowing antibiotics and biocides to be more effective against any bacteria in the wound bed. The protective properties of a mature biofilm would reject any penetration of most cleansing solutions and render these solutions largely ineffective.

Biofilm may reform quickly, even after repeated debridement sessions, yet a time-dependent window of opportunity exists after debridement during which biofilm is more susceptible to treatment, particularly with topical antiseptics.⁴ Ideally, cleansing the wound should be performed with each dressing change and before and after debridement.

Clinicians should educate patients and caregivers on the procedures of wound cleansing, which can be done following dressing changes in their homes. Patients and caregivers should be informed of how to use antimicrobial cleansers when they change dressings to remove loose material and work against newly exposed bacterial cells. Constant disruption of bacterial cells is essential between debridement sessions to prevent biofilm maturation.

Dressing

Once the cleansing is complete, clinicians should assess exudate levels and other individual characteristics of the wound that a dressing can address (eg, odor or moisture management). Antimicrobial dressings are used because microbial cells involved in biofilm formation and reformation show increased sensitivity to antimicrobials and antibiofilm agents.

This use of antimicrobial dressings continues wound bed preparation best practices by maintaining an environment that arrests biofilm formation. Clinicians should determine the frequency of dressing changes based on the unique characteristics of the wound along with patient factors, such as the patient’s ability to perform dressing changes at home without causing additional trauma to the wound or how often they can visit the office if they cannot perform dressing changes at home.

Conclusion

Wound bed preparation is essential to prevent and manage biofilm. Because biofilm is resistant to various treatments and no one approach is 100% effective, clinicians should create a treatment plan that uses multiple, varying treatments to eradicate and prevent further biofilm formation. These goals can be achieved through debridement, cleansing, and appropriate dressing choice combined with best practices of patient communication and wound bed preparation.

References

1. Atkin L, Bucko Z, Conde Montero E, et al. Implementing TIMERS: the race against hard-to-heal wounds. J Wound Care. 2019;28(3):S1-S49.
2. Sussman G, Swanson T, Black J, et al. Ten top tips: reducing antibiotic resistance. Wounds Int. 2010;5(4):4-8. Accessed May 28, 2022. http://tinyurl.com/kp5u285
3. Attinger C, Wolcott R. Clinically addressing biofilm in chronic wounds. Adv Wound Care (New Rochelle). 2012;1(3):127-132. doi:10.1089/wound.2011.0333
4. Schultz G, Bjarnsholt T, James GA, et al. Consensus guidelines for the identification and treatment of biofilms in chronic non healing wounds. Wound Repair Regen. 2017;25(5):744-757.