Chronic wounds cause pain and misery to millions of people around the world. Removing slough and biofilm through professional debridement is crucial for managing infected wounds and promoting healing. Monofilament devices offer a very effective method for debridement and bring welcome pain relief to patients.
We all experience small injuries every now and then. Usually they heal without any problems. When they don’t and even become infected, patients suffer for weeks or possibly months. Also known as a “silent epidemic”, chronic or hard-to-heal wounds represent a worldwide malady that affects one to two per cent of the population in developed countries.1 Prevalence can even reach three to five per cent when considering the senior population, because ageing slows wound healing processes.2
With an estimated annual cost of USD 20 billion in the United States alone, the management of chronic wounds also has a massive economic impact on patients, health systems and countries3. Dealing with chronic wounds often results in a reduced quality of life for the patients who experience pain, uncertainty, reduced mobility, decreased work ability, and social isolation.
More and more clinicians and researchers are focusing on better understanding and assessing chronic wounds, as well as on developing new treatment modalities. Dr Kevin Woo, an associate professor at Queen’s University in Ontario, Canada is an expert in the field of chronic wound management. “It takes a lot of thinking outside the box to understand the comprehensive picture of all factors that can influence chronic wound healing,“ he explains. His research focus is on wound-related problems, wound care, chronic wound management, and clinical management of patients with chronic wounds. Understanding and relieving pain is the central focus of his research.
The different types of chronic wounds display various characteristics, depending on the underlying pathophysiological mechanisms. The Wound Healing Society classifies chronic wounds in four categories: pressure ulcers, diabetic ulcers, venous ulcers, and arterial insufficiency ulcers4. “Chronic wounds are very complex, and their management often involves many different systems and many different comorbidities,” remarks Woo. “Unless we identify the factors that impair wound healing – whether poor circulation, infection, or diabetes-related issues for example – treatment is not going to be effective.”
One challenge for clinicians in wound care is determining whether the wound is infected, as sometimes wounds do not display the five typical signs of infection: redness, temperature, pain, swelling and impaired function. In this case, checklists can be used to assess the wound, to differentiate between superficial infections and infections on a deeper skin level, and to identify patients who need specific local wound treatment (see additional elements).
“I created the UPPER and LOWER system to make it easier for clinicians to remember the covert signs of wound infection, because the ways infections display themselves in chronic wounds are very different compared to soft tissue infection, for example,” explains Woo.
This score helps to separate wound infections into the upper, or localised environment, versus the inner, deep, lower compartment. This differentiation supports clinicians identify the appropriate treatment for removing bacteria from the wound environment. “The score helps clinicians identify the problem, so they have a more accurate and better data basis to use when deciding on the appropriate treatment,” Woo emphasises. “What we are proposing is using local antimicrobial dressings for upper, localised infections versus antibiotic systemic agents for lower and deeper types of wound infections.”
The UPPER and LOWER score has been internationally adopted in many wound care centres, as it is easy to remember. “It is a work in progress. As we understand wound infection better, the scoring system continues to evolve, and the signs might change,” says Woo.
Biofilm plays an important role in the management of chronic wounds, as it is present in up to 80 per cent of all chronic wounds. It triggers inflammatory responses and hinders wound healing5. “The body’s immune system tries to attack the biofilm but fails because the microorganisms are embedded in a slimy matrix. However, prolonged inflammatory responses lead to the degradation of proteins that are necessary for wound healing. This is when chronic wounds become hard to heal. Biofilm also represents a repository for bacteria that are just waiting for the opportunity to proliferate.”
The Biofilm Based Wound Care (BBWC)6 principles emphasise the need to remove slough, necrotic tissue and biofilm from a wound, as well as the importance of applying wound dressings with antimicrobial agents* to control the bacterial growth and prevent a rapid rebuilding of the biofilm. “We need to disturb the biofilm structure and disrupt the protective shield for the bacteria, making them more vulnerable to the attack of antimicrobial substances,” says Woo.
Debridement refers to the removal of non-viable tissue, debris and biofilm from wounds and was first practised in the late 18th century by French surgeons, who made incisions into the skin and deep fascia to release pressure from localised swelling after ballistic injuries7. Debridement is the crucial first step of modern wound management. It is necessary to clean the wound bed and its surrounding skin and thus promote healing. “Without debridement, the necrotic tissue becomes an area where bacteria can grow. Then even antibiotics are not helpful in managing wound infection, and wounds are even less likely to heal,” explains Woo.
The most common types of debridement are autolytic, enzymatic, surgical, and mechanical. Autolytic and enzymatic debridement methods use the body’s own processes or chemical agents to break down necrotic tissue and slough, respectively. Surgical debridement uses sharp instruments to remove necrotic tissue and is mostly used for very large wounds. Mechanical debridement requires the use of mechanical forces to remove wound debris8.
Sterile pads of monofilament fibres (Debrisoft® Pad / Debrisoft® Lolly) have been developed to mechanically remove biofilm and slough (Video). A recent study conducted by Woo and colleagues examined their effectiveness on ten patients with chronic wounds9. Their findings suggest that these pads are beneficial for the removal of slough, as the average wound size decreased, exudate was reduced, and the UPPER score improved for every patient. “Using monofilament fibre pads for debridement offers many advantages for both clinicians and patients.
The pads are user friendly and can be used by professionals and – in the USA and Canada – even patients. They represent an effective solution for mechanically removing loose slough and biofilm. They also have positive effects on patients, as they can positively influence wound healing and lessen wound infection, which is often associated with pain and increased odour. By removing the burdens of superficial bacteria and slough, the wound healing is quicker, with less exudation and odour, and as a result, patients have a better quality of life. Moreover, monofilament fibre pads also have a positive effect on compliance as the patients are empowered to engage and to look after the wounds,” remarks Woo.
The major role of pain during debridement is the subject of a study conducted by Dr Woo on 96 patients with chronic wounds in 2015, dealing with the effects of anxiety on the experience of pain10. “What I found in this study is that patients experience a lot of pain during dressing change and wound cleansing, because scrubbing was often involved to remove the non-viable tissue. The anticipation of this pain would then trigger anxiety, that can lead to increased pain.”
Debridement with monofilament fibre pads comes with low pain levels for patients during the procedure. “I remember two patients I treated with the pads. I was very conscious about the pain level. However, the patients did not experience any discomfort. When I did not have the pads with me, the patients complained, because the wounds looked so much healthier after debridement,” concludes Woo. His findings are supported by other studies11,12, which showed how debridement using a monofilament fibre pad is convenient, cost-effective, as well as virtually painless (see also media).
When dealing with chronic wound patients, attending clinicians should quickly assess the wound, and choose appropriate wound management strategies. In wounds that are prone to contamination, removing slough and biofilm is very important. By lowering the risk of critical colonisation and infection, debridement can bring pain relief to the patient and positively influence chronic wound healing.