Wound Bed Preparation: Debridement

Wound bed preparation is the first step in changing a chronic wound into an acute wound that is capable of advancing through the stages of wound healing. Debridement is the initial process and can be accomplished through several techniques.
Wound Bed Preparation: Debridement

Wound bed preparation is the process of eliminating barriers to wound healing and creating an environment in which the body can use the natural healing mechanisms to achieve wound closure.  This assumes that the underlying comorbidities are identified and managed before and during the entire interim of wound treatment.  A well-documented approach to wound bed preparation developed by Dr. Vince Falanga and Dr. Gary Sibbald is expressed by the acronym T/DIME, and includes the following steps:

T/D – debride the necrotic tissue

I – treat the infection/inflammation

M – manage the moisture

E – facilitate migration of epithelial cells at the edges

Debridement is the removal of non-viable tissue, exudate, and bacteria that are impeding the wound healing process, thus changing the wound environment from a chronic state to an acute state in which the cells needed for the proliferative phase of healing are activated.  Selecting the appropriate method of debridement is critical for optimizing wound healing, minimizing patient discomfort, and utilizing resources efficiently.[1]

The decision to debride a wound begins with assessment of the overall status of the patient: arterial perfusion of any lower extremity wound, nutritional status, medications that may influence healing, mobility and gait, pain levels, and amount of tissue to be removed.  Before beginning any actual removal of tissue, debride with the EYES!  Carefully observe the wound for the amount and type of tissue that needs to be removed, adherence to any viable tissue, amount of time required for the procedure – and explain the procedure to the patient.  If sharp debridement was the chosen approach, I always found it helpful to start with the easy stuff, especially when the task seemed daunting, meaning the loose eschar at the edges, the thick exudate, the scaly or callused edges.  This approach allowed a better view of the underlying tissue, a clearer assessment of how much needed to be removed, and time to develop a long-term plan when more than one debridement session was required.  It also gave the patient time to develop confidence in me as a clinician and to understand that removal of nonviable tissue is comparable to cutting one’s hair, when done carefully one does not feel it.  If pain is a concern, options other than sharp debridement and the use of systemic or topical anesthetics may need to be considered, as discussed below.

A brief review of the debridement techniques and when they are most effective are as follows:

Autolytic – the process by which the body’s endogenous enzymes are contained to loosen and liquefy necrotic tissue.  This is achieved by applying an occlusive dressing (e.g. transparent film, hydrocolloid, foam) over the entire wound bed for 24-48 hours, then washing away the autolyzed debris after dressing removal.  A thin layer of hydrogel can also be applied to the surface before applying the occlusive dressing.  WHEN TO USE:  on superficial, thin eschar.  WHEN NOT TO USE: infected wounds

Enzymatic – application of an enzymatic ointment to the wound surface to target and break down devitalized collagen in the wound bed.  May also be used in conjunction with cross-hatching of eschar to facilitate sharp debridement.  WHEN TO USE: on tightly adhered fibrous tissue, on painful wounds (e.g. vasculitis), prior to sharp debridement of thick adhered eschar; for maintenance or on-going debridement of accumulated dead cells after initial debridement of eschar.  WHEN NOT TO USE: in conjunction with products containing detergents or heavy metals that inactivate the enzymes; on infected wounds.

Mechanical – uses external forces to remove exudate and loose debris.  Methods include soft abrasion with sterile gauze, pulsed lavage with suction (PLWS), low-frequency contact ultrasound (LFCU).  Whirlpool and wet-to-dry dressings, previously standard of care for mechanical debridement, are no longer recommended because of the non-selectivity and potential damage to healthy tissue.  WHEN TO USE: wounds with loose debris and exudate, wounds with undermining and tunneling (PLWS), wounds with tightly-adhered fibrous tissue and wounds with biofilm (LFCU).  WHEN NOT TO USE: painful wounds without prior pain medications (either systemic or topical), large amounts of thick eschar.

Instrument – either sharp or surgical; uses scalpel, scissors, forceps and curretts to remove non-viable tissue.  Sharp debridement is more selective than surgical and can be performed in any setting by a trained clinician whose state practice act allows it; surgical debridement (also referred to as incision and drainage or I&D) is performed only by MDs, PAs, DPMs, or osteopaths with the patient’s conformed consent.  WHEN TO USE: sharp debridement: on any wound with non-viable tissue; to remove callus around a diabetic foot ulcer, to remove senescent cells at the wound edge; surgical debridement: when the patient cannot tolerate sharp debridement due to pain, when there is a larger amount of necrotic and/or infected tissue than can be adequately removed with sharp debridement, when there is a high risk of bleeding, when necrotic bone is present in the wound.  WHEN NOT TO USE:  when there is inadequate perfusion of the extremity to support wound healing, when the eschar is attached at the edges on a non-mobile patient and there is no sign of infection, when the patient is terminal and palliative care is being provided (unless infected tissue is a concern).

Biological – involves the use of maggot therapy to remove necrotic tissue, remove microbes, and promote healing.  WHEN TO USE: the patient cannot tolerate other methods of debridement; WHEN NOT TO USE:  on thick dry eschar (remove by sharp debridement before initiating maggot therapy), when patient is offended by the concept!

In summary, removal of devitalized tissue in an initial and critical part of preparing any wound environment for healing.  Selection of the best method requires training and skill for optimal results, therefore referral to a wound specialist is recommended when debridement is deemed necessary.

Further detailed information on wound debridement can be found at the following:

Weir D, Scarborough P.  Wound debridement.  In Hamm R (Ed), Text and Atlas of Wound Diagnosis and Treatment: 2nd edition.  New York: McGraw Hill Education.  2019, 349-371.  Available at https://accessphysiotherapy.mhmedical.com/book.aspx?bookid=1334




[1] Kamolz L, Wild T.  Wound bed preparation: The impact of debridement and wound cleansing.  Wound Medicine.  2013;1:44-50.