Non-surgical Debridement of Burn Injuries: Difference between revisions

No edit summary
m (Jess Bell moved page Non-surgical Debridement in Burn Wound Treatment to Non-surgical Debridement of Burn Injuries: Changed again to match course name)
 
(38 intermediate revisions by 3 users not shown)
Line 1: Line 1:
<div class="noeditbox">
 
This article or area is currently under construction and may only be partially complete. Please come back soon to see the finished work! ({{REVISIONDAY}}/{{REVISIONMONTH}}/{{REVISIONYEAR}})
</div>
<div class="editorbox"> '''Original Editor '''- [[User:Stacy Schiurring|Stacy Schiurring]] based on the course by [https://members.physio-pedia.com/instructor/diane-merwarth/ Diane Merwarth]<br>
<div class="editorbox"> '''Original Editor '''- [[User:Stacy Schiurring|Stacy Schiurring]] based on the course by [https://members.physio-pedia.com/instructor/diane-merwarth/ Diane Merwarth]<br>
'''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}}     
'''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}}     
Line 7: Line 5:
== Introduction ==
== Introduction ==


Burn wound injuries are a common injury worldwide. Burn wound therapy continues to be a challenging and dynamic field of medicine and rehabilitation. The first and most critical step in burn wound care and wound bed preparation is the removal of eschar and other non-vitalised tissue. This helps to reduce the bioburden and potential for biofilm formation in the wound, minimises the risk for infection and compartment syndromes, and promotes healthy granulation and wound healing.<ref name=":5">Thomas DC, Tsu CL, Nain RA, Arsat N, Fun SS, Lah NA. [https://pdf.sciencedirectassets.com/305626/1-s2.0-S2049080121X00118/1-s2.0-S2049080121008268/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEBMaCXVzLWVhc3QtMSJIMEYCIQDXqZvB0qV%2B1G8Pq%2BbhL9eb8JKvZ293Xn%2Fi29FYhFwtuAIhAIof6tjK25D4MwYZk4%2BfDR5BcONqDAEGVAdHj%2FrMoCe4KrsFCKv%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEQBRoMMDU5MDAzNTQ2ODY1IgzI2t5o9ekMQn5LWm0qjwW%2BQFe1PjXh1X5TY195mYBno01j%2FF4P8M%2ByvkszSkgXE2iVs6fQ1Cc6vPEDfSBbGBYSrlttnDipKUisL4Xulbq6Qk7865d2rxBq%2BQdQ5%2BoptSbJcInNO%2F2%2Fo7fMBRBpagczrtYzAjr7N1mwwEAFW4IjlpgRVepCilRQvY6guwi3GomErfl78HhnABL4CfqhAG6adUNzq9SjaGA4vV0DeXNr3pN4Zp%2BtCd5aqLzGXhQiQ5kxSsr2IfaLnggjaEO4X04Gnl6MuxxTcqS7aCaN%2FQfdk0LktHVhmhBcrwIg%2Fq8jAniUCx52A2JNnUJhRnObP3MXGD2dIdJj39Nehmt0ixKJKF6yhwa8dMfhG93Cuv1eew8SQEZIld%2FSqcidfKmiiiL%2F24TQlOEXDi3anumxpnvqg29zxPxHVTOx8PwcSWp6Hme8ic7GtlxVlCI6ZnLeR9JPib4yCkGnhzkaBRKzG08PstI7bR4Xj%2BMxP7e5Exnuj8QYhMo00jOy%2BA3SuXje%2FAWSc9M%2Fp2Ad6b5SUXVLgjweC%2FpL%2BSAfp%2Bl%2FDX6g6xsWXdODWdYWPhLX0tp%2BS3Seju%2Fa3doEyuLLppfKZgSWWSOZe7IoRoJO7pGXZ%2BvO%2BdDYBPzgdTSeUehCv7PWXfiomMXO3bLLpNaCOcxb93Zm0Wy6YosGKc6kcS1d8CaIcC2aEdfivkQ%2B2baJN43v6XoafNKWAvOHgGTDvAIchbhX4qlWRwfisUHhhRxEtaMJ%2FEKlho9IIWhQ7rXl1U3lhqFIhaS0SNxdHofg4O%2Blt7cUAz2%2BZkqwEM3gKATQ9NzHc3QOgTj40LR3w1%2FC9FXG8EJ0BOorBejZ7hejs1agc6z%2BJ5olbAKCm5SxgvqCz71wgeMvMKDMmqYGOrABWJNKu4TFMvTGnIaBxuO91P1JjAXAP89TIpCkG3ImZvn3srVwyM%2FeaAYufW74r86BxNgaB26cgEoTN09M9brp69krIrpnJzRRXUNhjfgLdfldqBRD2zTRb9xI0Vwf3hb4XFf4Ch7LeN%2BfXhHZdHsvd22%2B755qvMI%2BINbYLDQRxuH4gGkQJCAiDjXrPsGO6YFgwVpjL71CuZxiQkLCsMfCOWLlaM2U137LH8MFvoZS0NU%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20230730T185142Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY3X57FJD4%2F20230730%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=06c7254c4a36c3866aa178e8f4f54fb9db667b84310acf8f458fb8468746bea9&hash=236ac90576b00b8760fee49338ba29c1af7b632fe160445ba8c387ef2fd92ff1&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S2049080121008268&tid=spdf-6eb7c185-2d48-4dd1-a284-355576294bb2&sid=d43c74572cc9d14358480c1379e5bede925agxrqa&type=client&tsoh=d3d3LnNjaWVuY2VkaXJlY3QuY29t&ua=1312570a0b04060c5258&rr=7eefcb687956aa49&cc=us The role of debridement in wound bed preparation in chronic wound: A narrative review]. Annals of medicine and surgery. 2021 Nov 1;71:102876.</ref><ref name=":6" />


Since the 1970s, early surgical excision and debridement of burn wounds have been the standard of care. Surgical debridement can quickly and fully remove non-viable and necrotic tissue from a burn wound. However, it has the disadvantages of causing huge trauma, excessive bleeding, and being very non-selective in the removal of unwanted tissue in the burned area. Alternative non-surgical methods of debridement have been explored and researched. These methods provide less invasive and more selective options for the removal of non-vitalised tissue from a burn wound.<ref name=":6" />


The types of debridement that I'm going to talk about today include mechanical, autolytic, local sharp debridement, biosurgery or larval therapy, otherwise known as maggot therapy, and enzymatic debridement.
This article will explore five methods of non-surgical debridement: (1) mechanical, (2) autolytic, (3) local sharp, (4) biosurgical, and (5) enzymatic.


'''Please see [[Wound Care Terminology|this article]] for a list of useful wound care terminology.'''  
'''Please see [[Wound Care Terminology|this article]] for a list of useful wound care terminology.'''  


== Indications for Debridement ==
== Indications for Debridement ==
'''Indications for debridement:'''<ref name=":0">Merwarth, D. Management of Burn Wounds Programme. Non-Surgical Debridement of Burn Injuries. Physioplus. 2023.</ref>
'''Indications for debridement:'''<ref name=":0">Merwarth, D. Management of Burn Wounds Programme. Non-Surgical Debridement of Burn Injuries. Physioplus. 2023.</ref><ref name=":6">Heitzmann W, Fuchs PC, Schiefer JL. [https://www.mdpi.com/1648-9144/56/12/706 Historical perspectives on the development of current standards of care for enzymatic debridement]. Medicina. 2020 Dec 17;56(12):706.</ref>
 
* '''Remove devitalised tissue.''' This is the primary function of debridement.<ref name=":1">Manna B, Nahirniak P, Morrison CA. Wound Debridement. [Updated 2023 Apr 19]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507882/


* '''Remove devitalised tissue''', this is the primary function of debridement. The presence of non-living tissue in a wound bed impedes wound healing by:
last accessed 27/July/2023)</ref> The presence of non-living tissue in a wound bed impedes wound healing by:
** acting as a nutrient source and ideal living environment for unwanted microbes which can cause infection
** acting as a nutrient source and an ideal living environment for unwanted microbes which can cause infection
** creating a physical barrier for re-epithelialisation  
** creating a physical barrier for re-epithelialisation  
** creating a barrier against topical antimicrobial agents which limits their ability to manage infection in the wound  
** creating a barrier against topical antimicrobial agents, which limits their ability to manage infection in the wound
* '''Stimulate the wound bed''' in chronic wounds to reinvigorate the wound healing cascade. The presence of non-living tissue in a wound bed effects the wound healing cascade by inhibiting:
* '''Stimulate the wound bed''' in chronic wounds to reinvigorate the wound healing cascade.<ref name=":1" /> The presence of non-living tissue in a wound bed affects the wound healing cascade by inhibiting:
** angiogenesis (the formation of new blood vessels from existing vasculature)
** angiogenesis (the formation of new blood vessels from existing vasculature)
** granulation tissue formation
** granulation tissue formation
** re-epithelialisation  
** re-epithelialisation  


Surgical excision of non-viable tissue is the standard of care, however there are times when less aggressive debridement methods are required.  This can include:<ref name=":0" />  
Surgical excision of non-viable tissue is the standard of care. However, there are times when less aggressive debridement methods are required, including the following:<ref name=":0" />  


# Medically unstable patients who could not tolerated sedation and/or surgical interventions
# Medically unstable patients who would not tolerate sedation and/or surgical interventions
# Surgical resources not available
# When surgical resources are not available
# Non-surgical management is preferred  
# Non-surgical management is preferred  
# Areas of deep partial and full thickness injury are small and can be properly managed with less invasive methods
# Areas of deep partial and full thickness injury are small and can be properly managed with less invasive methods
# Area of the burn wound injuries is not serious enough to warrant surgery, or r
# The area of the burn wound injuries is not serious enough to warrant surgery
# The risk of surgery damaging vital structures is greater than non-surgical care such as on the fingers or hands  
# The risk of surgery damaging vital structures is greater than non-surgical care, such as on the fingers or hands


Images for this section: eschar, necrotic tissue, slough, bioburden, biofilm, and those apoptotic or senescent cells that accumulate on the surface of the burn.  
<blockquote>
==== '''Clinical Pearls: a deeper look at eschar''' ====
Burn wound injuries lead to the formation of a non-viable tissue called '''eschar'''. Similar to burn classification, the depth of eschar in a wound bed may be superficial or deep. The presence of any non-viable tissue, including eschar, in a burn wound bed, serves as a base for bacterial growth and may result in an inflammatory response, which can contribute to the extension of the burn wound injury. It also creates the potential for local and systemic infection. Therefore, the removal of eschar is a primary focus of burn wound therapy.<ref name=":7">Gurfinkel R, Rosenberg L, Cohen S, Cohen A, Barezovsky A, Cagnano E, J Singer A. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2940971/ Histological assessment of tangentially excised burn eschars]. Canadian Journal of Plastic Surgery. 2010 Sep;18(3):33-6.</ref>


According to a study by Gurfinkel et al.,<ref name=":7" /> the initial diagnosis of the extent of the eschar within the wound bed is the first step in any debridement strategy. Unfortunately, assessing burn wound depth through the opaque eschar is "difficult, if not impossible." Furthermore, the depth of a burn injury can be inconsistent throughout the damaged area. The colour and texture of the eschar found within a burn wound can be misleading even to wound care experts. Very often, the extent and depth of tissue damage may only be determined days after injury when the secondary damage has already extended beyond the original burn wound.<ref name=":7" />
Keep this information in mind as you continue to learn about the types of non-surgical debridement. Consider how a more selective form of debridement can spare tissue which has the potential to heal, and would limit the amount of ongoing tissue trauma which occurs following a burn wound injury. What psychological effect could this have on a patient following a burn wound injury?</blockquote>
== Non-surgical Debridement ==
== Non-surgical Debridement ==
Non-surgical debridement is the removal of materials which are incapable with healing are removed from a wound bed without using sharp excisional methods into viable tissue in sterile surgical setting. Examples of unwanted materials in a wound can include: eschar, necrosic tissue, bioburden, biofilm, or foreign matter.
Non-surgical debridement is the removal of materials which limit or impair healing from a wound bed by means other than sharp excisional methods into viable tissue in a sterile surgical setting. Examples of unwanted materials in a wound can include eschar, necrotic tissue, bioburden, biofilm, or foreign matter.


=== Mechanical Debridement ===
=== Mechanical Debridement ===
Definition
<blockquote>"Mechanical debridement is a nonselective type of debridement, meaning that it will remove both devitalized tissue and debris and viable tissue. It is usually carried out using mechanical force."<ref name=":1" /></blockquote>The amount of force applied during mechanical debridement is subjective and is based on the wound care professional's clinical skill and comfort level. Currently, there is little evidence in the literature to support the use of mechanical debridement in the treatment of burn wound injuries.<ref name=":0" /> 


Examples
'''Indications for mechanical debridement:'''


Advantages
* acute and chronic wounds with moderate to large amounts of non-viable tissue
* can be used regardless of the presence of active infection<ref name=":1" />


Disadvantages
'''Contraindications for mechanical debridement:'''


'm going to start with mechanical debridement, which is essentially the application of a frictional force to remove the surface debris and contamination on the wound. It's a physical force to wash away that debris. That amount of force is very subjective based on caregiver skill and comfort level, as well as patient tolerance. And unfortunately, there is very minimal evidence to support any type of mechanical debridement, and specifically, there is a very little amount of evidence related to burn wound management.
* greater percentage of granulation tissue than devitalised tissue in the wound bed
* inability to control pain
* patients with poor perfusion<ref name=":1" />


There are various methods of mechanical debridement that can be used. All mechanical debridement is considered non-selective, because it can damage healthy tissue as well as any of the non-viable tissue that you're targeting with whatever method of mechanical debridement you're using. Some are less non-selective than others because you can target specific areas, but they're all considered non-selective. Some of the more common methods include the moderate-to-high pressure irrigation, such as a pulsatile lavage device, which is probably one of the safest methods of mechanical debridement because the amount of pressure that comes from that device is well controlled and known to be safe for the surface of wounds, including burn wounds.


A syringe with a known gauge needle can also be used for mechanical debridement and provide a known amount of pressure. However, that's ineffective for burn wounds because of the size of the irrigating device and the size of the burn wound. A shower is also a method of mechanical debridement, as is whirlpool. Although whirlpool is no longer recommended for use in cleaning or debriding burn wounds, unless it's the only option that you have to initially get that burn wound cleaned. Putting a patient in a whirlpool and immersing them in that water can be very physiologically taxing. The heart rate goes up, the blood pressure goes down, the respiratory rates go up. And they become very hypothermic when they come out of the whirlpool. And all of those are very negative effects on that patient, as well as the risk of cross-contamination from the patient's own skin being washed, and then recontaminating the burn wound, as well as any bacteria, including biofilms, that commonly live in the pipes and on the surfaces of the whirlpool devices. And so even though you clean them, those biofilms particularly remain and can recontaminate the patient or another patient when they're immersed in that same whirlpool tank. So again, whirlpool, if it is the only option you have, we recommend doing it for a very short period of time, such as 10 minutes as opposed to the traditional 20- or 30-minute treatment time, and only doing it for one or two times to get that burn wound really clean. And then move on to another less damaging type of mechanical debridement or other care that is indicated for that burn wound.
'''Examples of mechanical debridement:'''


Another method of mechanical debridement is scraping, using a scalpel, the edge of a scalpel, a curette, or some other flat instrument, such as a tongue blade, to scrape the surface of the wound and remove any loosened debris that has accumulated on that burn wound. Wet-to-dry dressings is another very well-known form of mechanical debridement, and again, is no longer considered standard of care. It essentially involves moistening gauze with either saline or an antimicrobial agent, placing it on the surface of the burn wound, allowing it to become dry, and then essentially ripping it from the surface of the burn wound. As that dressing becomes dry, anything on the surface of the wound adheres to the gauze. So that can be loosened necrotic tissue as well as granulation tissue. And in the process of removing the gauze, you're removing the granulation tissue along with the non-viable tissue that you're trying to get to.
# '''Pulsatile lavage'''. Involves moderate-to-high pressure irrigation, which is well controlled and known to be safe for the surface of wounds, including burn wounds.<ref>Wan J, He J, Chen L, Qiu L, Wang F, Chen XL. [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9661869/ Retrospective Study from a Single Center on the Efficacy of Pulsed Lavage Following Excision of Burns≥ 30% of the Total Body Surface Area in 63 Patients]. Medical Science Monitor: International Medical Journal of Experimental and Clinical Research. 2022;28:e937697-1.</ref>
# '''Wound Irrigation'''. Can be achieved using a syringe with a known gauge needle to provide a known amount of pressure. Not commonly effective for use in burn wound injuries. 
# '''Shower'''.  Please see [https://www.physio-pedia.com/Burn_Wound_Treatment:_Cleansing_and_Solutions?utm_source=physiopedia&utm_medium=search&utm_campaign=ongoing_internal#Wound_Cleansing_Strategies:_Hydrotherapy this article] for more information.
# '''Whirlpool'''. Please see [https://www.physio-pedia.com/Burn_Wound_Treatment:_Cleansing_and_Solutions?utm_source=physiopedia&utm_medium=search&utm_campaign=ongoing_internal#Wound_Cleansing_Strategies:_Hydrotherapy this article] for more information, especially regarding the physiological responses and risks of whirlpool use with burn injuries.
# '''Scraping'''. Achieved using the edge of a scalpel, a curette, or some other flat instrument, such as a tongue blade, to scrape the surface of the burn wound and remove any loosened debris.  
# '''Wet-to-dry dressings'''. Involves applying gauze which has been moistened with either saline or an antimicrobial agent on to the surface of the burn wound, allowing the gauze to dry, then removing it from the burn wound surface. As the gauze dries, anything on the wound surface, including loosened devitalised tissue or healthy granulation tissue, can adhere to the gauze. When the gauze is removed, both types of tissue are ripped off the wound surface. This method of debridement can be very painful and highly non-selective.
# '''Soak and wipe'''. Involves applying towels or gauze saturated with saline or an antimicrobial solution to the surface of the burn wound and allowing them to "soak" for 5-10 minutes. Next, using a saturated gauze, wipe the wound surface with an applied force in circular motions to remove debris. The wiping is performed to the patient's tolerance. Caution should be taken to only use clean gauze when wiping, and discard gauze as it collects devitalised tissue. When treating a large burn wound, only expose a small area at a time to prevent hypothermia. Please see [https://www.physio-pedia.com/Burn_Wound_Treatment:_Cleansing_and_Solutions?utm_source=physiopedia&utm_medium=search&utm_campaign=ongoing_internal#Wound_Cleansing_Strategies:_Hydrotherapy this article] for more information.


So it's very painful, as well as being very non-specific or non-selective. So unless you're using it for a very specific reason in a very targeted area, a wet-to-dry dressing is really not indicated for burn care. And then the other method of mechanical debridement that I'm going to talk about in some detail is the soak followed by either a scrub, and I use the term scrub loosely, or wipe to remove the loosened, non-viable tissue from the surface of the wound. There is some evidence to support the use of mechanical debridement. There was one small study that was done on venous leg ulcers using a fluorescent device. This particular device could measure bacteria on the surface of the wound of 10 to the fourth colony-forming units per gram of tissue and greater. So they used this device to measure the amount of bacteria on the surface of various venous leg ulcers and the surrounding peri-wound skin, and then they performed mechanical debridement using saline-soaked gauze, and then they re-measured the amount of bacteria on the surface of the wound and they found a 99.4% decrease in the amount of measurable bacteria on the surface of the wound. Remember, there could still be bacteria there of less than 10 to the fourth. And they found that mechanical debridement in this case was very effective.


So essentially, the procedure for performing the soak and then scrub or wipe on the burn wound starts with soaking the burn wound, if necessary, to soften the eschar and the non-viable tissue. So you take towels or large gauze pads, you saturate them with saline, or if indicated, in antimicrobial solution, lay them on the surface of the burn wound and allow them to soak for five or 10 minutes. If you're using an antimicrobial agent such as hypochlorous acid, some of the manufacturers recommend you soak that for about 10 minutes before removing it. And then you take either gauze pads or a face cloth or other form of textile, you saturate it with saline or again, an antimicrobial agent if you feel that's indicated, and you apply a force on the surface of the burn wound in a circular motion, trying to remove any debris that has accumulated and that is loose enough to be wiped away using this method of debridement. You can continue this for as long as the patient tolerates it.
'''Advantages'''


Over fairly large surface areas of burn wound, it can be very efficient in treating large surface area burn wounds, but it's important that as that gauze pad or textile that you're using becomes dirty with what you've cleaned from the burn wound, that you discard that and start with a new gauze pad or textile so that you're not recontaminating areas that you've already cleaned. You continue this for, like I said, as long as the patient tolerates or until you become tired or it's time for you or a caregiver to move on to another patient. There is really no limit to the surface area covered other than fatigue on the part of the patient or the caregiver. However, it is important with large burns that you don't expose that burn all at the same time, because the evaporative effect of that burn being exposed to air can cause hypothermia as well as the burn can become very dry when it's exposed to air for that long. So it's recommended that with larger burn wounds, you only undress and clean one area at a time, re-bandage that area, and then move on to another area. But it can be very efficient with these large burn wounds and can be done at bedside with adequate pain management.
* Quick to perform with appropriate pain management
* Can be used with active infection 
* Efficient for larger wounds
* Effective at the bedside or in the outpatient setting with adequate pain management


The advantages to most of the forms of mechanical debridement that I talked about is it can be relatively quick with appropriate pain management. It's appropriate in the presence of active infection because you're actually removing some of that infection as you're cleaning the burn wound. It's very efficient for larger wounds. It can be effective at bedside or in the outpatient setting, again, with adequate pain management. And there was one study that showed the effectiveness of pulse lavage. This was a study that was done after surgical excision of the burn wound, then using pulse lavage to clean the surface of the burn wound, and then a skin graft is applied to that cleaned wound bed. And this study showed that using pulsatile lavage after surgical excision increased the success rate of skin graft take and decreased the amount of infection that occurred after that skin graft surgery.
'''Disadvantages'''  


The disadvantages of mechanical debridement. It's a short list, but they're pretty significant. It is a very non-selective form of debridement. As I said, you can target specific areas to make it less non-selective, but it's still non-selective. It's also very painful. So you do need to have adequate pain management, and as we all know, oral pain meds or IV pain meds can decrease the pain, but it doesn't take it away. So pain is still a factor throughout the process of performing mechanical debridement unless they're anaesthetised. And then again, specific to whirlpool, the risk of cross-contamination and the physiological stress is a strong negative for that particular modality.
* Very non-selective form of debridement
* Very painful


=== Autolytic Debridement ===
=== Autolytic Debridement ===
The next method of debridement I'm going to talk about is autolytic debridement. Autolytic debridement uses the endogenous phagocytic cells and proteolytic enzymes present in the person to debride the eschar and non-viable tissue. So it does require an intact functioning immune system for all of this to become most effective. Essentially, the eschar is either dissolved or is separated from the underlying dermis through this process so that it can be washed away or debrided away at that dressing change. Usually it's optimised by providing a very moist environment. And the best dressings to do this have been found to be hydrocolloids, hydrogels, transparent films, even medical grade honey, because it can provide some additional moisture, but something that reduces the amount of evaporation so that moisture is held at the wound surface, and that autolytic process can be optimised.
<blockquote>"[Autolytic] debridement is a natural process by which endogenous phagocytic cells and proteolytic enzymes break down necrotic tissue. It is a highly selective process whereby only necrotic tissue will be affected in the debridement."<ref name=":1" /></blockquote>This is the most conservative type of debridement. Autolytic debridement involves dissolving or separating eschar from the underlying dermis to allow it to be removed or debrided away. A moist dressing environment optimises autolytic debridement.<ref name=":0" />  The effectiveness of autolytic debridement depends upon the amount of devitalised tissue present in the wound and the true wound size.<ref name=":5" /><ref name=":1" />
 
'''Indications'''
 
* Recommended for non-infected wounds.<ref name=":0" /><ref name=":1" /> However, it can be used with other debridement techniques, such as mechanical debridement, if wounds are infected.<ref name=":1" />
 
'''Contraindications'''


The advantages of autolytic debridement is it's very selective because it only targets the necrotic tissue. It's essentially painless, although some people do report some pain depending on the dressing used. Most of the pain is related to the removal of dressing at the time of the dressing change. It's a fairly simple process. It can be used in an outpatient setting as this picture shows with these very small, well-defined burns and autolytic debridement can be very effective and manage those burns non-surgically very well.
* Immuno-compromised patients<ref name=":1" />


The disadvantages to autolytic debridement include it's a very slow process compared to surgical excision or even sharp local debridement that can be done on a wound. It's not indicated in the presence of an active infection because typically these dressings are left in place for multiple days at a time to allow that process to continue, and it's really not effective or efficient over large surface areas. I have not seen much reported using autolytic debridement on large surface area burn wounds.


Essentially the procedure is cleaning the surface of the burn wound with whatever procedure you use in your facility to clean burn wounds and then applying a moisture retentive dressing, typically occlusive or semi-occlusive, like I said. The most common ones are pictured here. Hydrocolloid is probably the most effective that I've seen. Transparent films are very effective also, but they don't manage drainage as well, so there's a lot of bubbling and peri-wound maceration can happen. And then the dressing such as petroleum-coated gauze where you use multiple layers of that gauze and add an ointment, either an antimicrobial ointment or just Vaseline, to hydrate that dressing as well as render it essentially occlusive and place that over the area that you want to perform autolytic debridement. All of those can be very effective.
'''Examples of dressings that facilitate autolytic debridement''':


The dressing is typically changed every three to four days. At the time of the dressing change, you do mechanical debridement, local sharp debridement, scraping, if that's indicated, to remove the necrotic tissue that's become softened through the autolytic process or that has been become separated from the underlying dermis, so you can debride that away. This picture is just an example, as I said, of a very well-defined burn wound where autolytic debridement can be very effective. The centre of that burn wound has also been sharply debrided to show there is a viable underlying dermis and local wound care could be very appropriate if that wound were to need skin grafting, that could wait until that wound is well granulated and ready to accept a skin graft. And the skin graft would be smaller because a lot of that wound could have potentially healed during the process of taking care of it locally.
# Hydrocolloids (most effective)
# Hydrogels
# Transparent films
# Medical grade honey<ref name=":0" />


=== Local Sharp Debridement ===
Local sharp debridement is another method of non-surgical debridement. It essentially uses a scalpel or a pair of scissors along with forceps or other devices to specifically and sharply remove non-viable tissue. The advantages of local sharp debridement is it can be fairly quick, if it's a small area that needs to be debrided. It's very specific, again, depending on the skill and the technique used. And it's good for bedside or outpatient procedures, if it's a small area that needs to be debrided as well. The person who performs the sharp debridement must be certified to do so. Depending on where you live and what your specialty is, some require additional certification. I know in the United States, physical therapists under their license are able to perform local sharp debridement. It varies state to state how deep they can go into the tissue when they're performing that debridement. But all of us are allowed to perform sharp debridement using these instruments. Most nurses in the United States, unless they go through the wound, ostomy, and continence courses and become wound certified, require additional certification through a course before they can perform bedside debridement on a patient. And it varies, again, like I said, from discipline to discipline and from country to country based on regulatory requirements.


Disadvantages to local sharp debridement is it can be painful because you are interacting with the viable wound bed, depending on how deep you're going with your debridement, and it is slightly invasive. So there is a risk of of bleeding, and if they're anticoagulated, that risk, you know, can be pretty severe. And so those things need to be assessed prior to performing the local sharp debridement.
'''Advantages'''


=== Biosurgical Debridement ===
* Very selective because it only targets the necrotic tissue
Biosurgery or larval therapy, otherwise known as maggot therapy, and
* Essentially painless
* Fairly simple process to utilise<ref name=":0" />


Another method of non-surgical debridement is biosurgery, or larval therapy, using maggots to debride the burn wound. Maggots come from the sterile larvae of the green bottle fly. They can be ordered either free range, meaning they're just loose, or in a mesh bag to be placed on the wound surface. I found one study that showed the use of maggots very effectively debriding a subcutaneous electrical burn wound. The basic mechanisms for larval therapy debridement is the secretions produced by the maggots have proteolytic enzymes that help to dissolve that nonviable tissue, and then the maggots ingest and digest that non-viable tissue to get rid of it. They also release ammonia, which increases the pH in the area of the maggots, and that is antimicrobial because bacteria don't like the higher pH and so they don't tend to grow in those areas. Maggots can be very effective in reaching areas that you can't access manually, deep crevices. Particularly with non-burn wounds, they can be very effective in getting in nooks and crannies and debriding burn wounds, but they can also be effective on burn wounds.
'''Disadvantages'''  


The advantages of maggot therapy include it's essentially painless, although there have been some reports of minimal pain. It's very selective because they're going after that necrotic tissue. It's fairly rapid and it can debride, as I said, areas that are difficult to access. The disadvantages of maggot therapy include the containment of the larvae. It has been found that the free-range or free-roaming maggots are much more effective and efficient than the ones that are contained in the mesh bags. There's also the patient or caregiver acceptance of having maggots on them, or otherwise known as the ick factor. And it's really not conducive to outpatient care because the difficulty in managing the larvae really needs to be under constant supervision, which is better done in the hospital setting.
* Slow debridement process when compared to other methods
* Not indicated in the presence of an active infection
* Not effective or efficient for use in burn wounds with large surface areas<ref name=":0" />


=== Enzymatic Debridement ===
=== Local Sharp Debridement ===
The final method of non-surgical debridement that I'm going to talk about in this module is enzymatic debridement. Essentially, enzymes are chemical agents that are composed of exogenous proteolytic enzymes to debride the necrotic tissue in a burn wound or any wound in general. Enzymes have probably been the most extensively studied of the forms of mechanical debridement that I've talked about today. And currently there are only two enzymes available on the market. There have been several over the years that have been available commercially for a while. And for various reasons, they have all been removed from the market except for these two remaining that are specifically approved as debriding agents, in their formulation.  
<blockquote>"Devitalized tissue (slough, necrotic, or eschar) in the presence of underlying infection is removed using sharp instruments."<ref name=":1" /> </blockquote>Tools that can be used for local sharp debridement include a scalpel,<ref name=":0" /><ref name=":1" /> scissors,<ref name=":0" /> and/or curettes.<ref name=":1" /> Local sharp debridement is performed by a skilled clinician with wound specialist training. In order to safely perform local sharp debridement, wound care professionals must be able to distinguish between tissue types and have a good understanding of functional anatomy as this procedure carries the risk of damage to blood vessels, nerves, and tendons.<ref name=":5" />


So Collagenase made by Santyl is the one that's been around the longest. It is derived from a bacterium, the clostridium histolyticum, and it was the first enzyme approved by the FDA in the United States, and it's been around for several decades. The second one is a bromelain-based enzyme derived from the stems of pineapples, and it provides multiple proteolytic enzymes in its formulation. It was approved for use as a debriding agent in Europe since 2012, under the name NexoBrid. It was just approved in the United States as of April 2023 for debridement of burn wounds, also under the name NexoBrid. There's been only one study and it was a recent study comparing directly the bromelain-based debriding agent with a collagenase debriding agent. Other studies have been conducted looking at each of these enzymes individually, they've been small studies, animal-based studies, and they typically compare the use of enzyme and monitoring wound healing, compared to the use of non-debriding agents such as silver sulfadiazine, or moist gauze dressings, or some other form of dressing that's not indicated for debridement.
'''Indications'''  


There have been multiple case reports, case series reports, expert opinion reports about the use of enzyme in managing burn wounds, and I'm going to discuss some of the findings of these in a little bit. There's also been consensus reached by large expert panel looking specifically at the use of NexoBrid as an enzymatic debriding agent, and providing guidelines of when it's appropriate and the best ways to use that particular agent. Everyone seems to agree that enzymatic debridement is not effective or adequate for severe deep burns or critical patients, where surgical excision is still the standard of care and necessary to provide the most optimal outcome and hopefully survival of that particular patient. However, the enzymatic debridement techniques can be an a very beneficial and effective adjunct to surgical excision as well.
* Recommended for infected wounds
* Can be combined with all the other debridement methods<ref name=":1" />


It's also been found that enzymatic debridement can be effective when surgery isn't feasible, such as in areas that are difficult to debride. The deep skin folds, those areas of thin dermal tissue that I talked about, like the fingers and the hands, as well as areas that are more important for cosmesis, where surgical excision can result in scars that are more deforming or less appealing to the patient once they've healed, where the enzymes are less aggressive and can provide a better outcome, such as the neck, the face, and the hands.
'''Contraindications'''


The advantages of using enzymatic debridement as a form of non-surgical debridement for burn care include both of the products that I've talked about, the collagenase and the bromelain-based enzyme are faster than autolytic debridement. They're very selective, although autolytic debridement is also selective, these particular devices are very selective to just the non-viable tissue on the burn wound, and they're good alternatives when surgical intervention isn't feasible either at that moment or for the length of the recovery of that particular burn patient. For collagenase, the advantages also include minimal pain associated with the use of collagenase. It's a simple application and it can be applied at bedside or in the outpatient setting.
* Patients on anticoagulation therapy due to bleeding risk<ref name=":0" />
* Intact eschar and no clinical evidence of an underlying infection<ref name=":1" />


The advantages specific to NexoBrid include it is a good alternative to surgery in those areas of function, such as the hands, which I mentioned earlier, where cosmesis is important such as the hands, the face, the neck, and those areas that are difficult to access, like deep skin folds, where getting in there manually can be challenging. NexoBrid is also much faster in accomplishing debridement than is collagenase.
'''Advantages'''


The disadvantages of enzymatic debridement, and these are really specific to the debriding agent. So the disadvantages of collagenase is it's a very slow process compared to the bromelain-based enzymatic therapy. It can cause maceration because you need a moist dressing to keep the enzyme activated and to facilitate the separation of that eschar from the underlying wound bed. You risk the maceration of the peri-wound skin as that drainage accumulates under that dressing. And collagenase can be deactivated by other agents that we may be using to provide care for that burn wound, specifically, silver-based dressings and Dakin's solution.
* Can be fairly quick
* Very specific form of debridement
* Good method for bedside or outpatient procedures<ref name=":0" />


The disadvantages that are specific to bromelain or NexoBrid include pain. The patients require ongoing pain management while the NexoBrid is in contact with the patient's burn wound, and that may be anaesthesia or a significant amount of sedation. According to the guidelines, the application is limited to a total body surface area of 15% or less, although there is some studies that indicate that it's safe for up to 30% total body surface area. It's only appropriate as an inpatient because of the pain medication that's necessary during the process, although there have been a couple reports where it was performed on an outpatient in a very small surface area. It requires a skilled provider to apply the NexoBrid and monitor the patient during the process. And bleeding can be a risk, particularly if the patient either prior to their burn injury or as a result of the changes related to their burn injury, has a coagulopathy where bleeding is difficult to control.
'''Disadvantages'''  


It has been found through various studies that the timing of applying the enzyme for debridement will affect the outcome of the success of that particular debridement. So most studies show that application of the enzyme within 12 hours of injury or up to 72 hours post-injury is the most optimal for getting the best success rate in using enzymes. If there is a delay of greater than 72 hours after burn injury before an enzyme is applied, then they recommend that a biopsy be done to rule out the presence of infection and if infection is found, to begin treating that infection while the enzymatic therapy is undertaken. And that the burn wound be pre-soaked, and this is really specific to the NexoBrid application process that the burn wound be pre-soaked to soften that eschar for at least two hours prior to the application of the enzyme.
* Can be painful<ref name=":0" />
* Can be an invasive procedure, depending on the depth of debridement<ref name=":1" />
* This technique requires specialised training, certification, and/or licensure.<ref name=":0" /> Please review your local practice act and complete appropriate and required training before performing local sharp debridement as part of a wound care treatment plan.


Compare/contrast collagenase and the bromelain-based enzyme in table:
=== Biological Debridement ===
<blockquote>Biological debridement (larval therapy, maggot therapy, biosurgery) uses sterile larvae of the green bottle fly to debride devitalised tissue. This is done via the release of proteolytic enzymes from larvae secretions and excretions, which dissolve necrotic tissue from the wound bed.<ref name=":1" />  </blockquote>The larvae are applied directly to the wound bed and can be either enclosed and contained in a "biological bag" or "free-range." Research has shown that biological debridement performed by free-range larvae is twice as fast as those enclosed in the biological bag.<ref name=":1" />


Now I'm going to review various studies that have been done with both collagenase and NexoBrid, starting with collagenase or Santyl collagenase. As I said, most of the studies compare using collagenase with non-enzymatic type interventions, such as the use of silver sulfadiazine, or even surgical excision. The mechanism of action for collagenase is specific degradation of denatured collagen, which is why it is considered so specific, because that's what eschar and non-viable tissue is, is denatured collagen. One of the studies was a summary through a systematic review that showed that collagenase was very effective in managing debridement of non-complicated burns of 10 to 20% total body surface area. They found no difference between surgery and using this enzyme to achieve debridement in paediatric burns. It resulted in shorter length of stay, less bleeding, and less surgery for partial thickness burn wounds, and in comparison to silver sulfadiazine, collagenase achieved a faster end result of a clean wound bed and more rapid healing.  
'''Other benefits of biological debridement include''':<ref name=":1" /><ref>Margolin L, Gialanella P. [https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1742-481X.2010.00234.x Assessment of the antimicrobial properties of maggots]. International wound journal. 2010 Jun;7(3):202-4.</ref>


Another study like the one that I mentioned previously compared collagenase to the bromelain-based enzyme, and it found that even after 14 days of daily application of collagenase, it was not successful in 100% removal of eschar, where the bromelain-based enzyme was successful in removing 100% of the eschar in one four-hour application. However, this was a very small animal study and more studies are obviously indicated.
# Bactericidal because the larvae ingest and digest bacteria
# Inhibiting bacterial growth by releasing ammonia into the wound bed, which increases the pH of the wound
# Breaking down existing biofilm at the wound bed and inhibiting new biofilm growth
# Direct ingestion of necrotic tissue


Another study was a small study that was sponsored by the industry that manufactures the collagenase, and it showed that in vitro, after surgical excision, the collagenase increased proliferation of the vascular endothelial cells and keratin; and in vivo, it enhanced re-epithelialisation and resulted in speedier wound closure. Another study reviewed multiple randomised controlled trials, and it found that the timing of enzyme application was best at about 48 hours after injury, but was essential in less than seven days after injury. And the same study also showed that collagenase was effective in removing fibrin and small areas of necrotic tissue.


The procedure for application of collagenase. One, it does require daily dressing changes. As I said before, it is a bacterial-based enzyme and it's not recommended to leave it on for more than 24 hours at a time. It's most effective when applied directly to the eschar or necrotic tissue in a thick, and by thick, they describe it as nickel thickness or a two-millimetre thickness of enzyme to the necrotic tissue. There is no risk to the surrounding viable tissue if you get collagenase on the viable tissue. It's more just effective use and monitoring the cost and being more cost-effective. And there's minimal risk to the peri-wound of maceration, but there is that risk because of the increased drainage produced while that enzyme is working, so you can protect the peri-wound skin with a skin protectant of some kind, or even just Vaseline so that the maceration does not become excessive.
'''Advantages'''


After the enzyme is applied, you cover it with a moist, non-adherent dressing. As I said before, you shouldn't use a silver-based dressing or anything with Dakin's on the dressing. Probably one of the easiest dressings to use over the collagenase is a Vaseline-coated gauze, such as Xeroform or Vaseline gauze, used in multiple layers to provide the moisture that the enzyme needs. It's also important to know that if there is not enough drainage or moisture from the wound itself to keep the enzyme activated, that the dressing put over the top of the enzyme needs to add moisture to the wound to provide that moist environment. The dressing, as I said, is changed daily at each dressing change. Other methods of mechanical debridement can be performed, just the soak and wipe or scraping, if there's loosened necrotic tissue to be removed, and then the process is repeated.
* Essentially painless<ref name=":1" />
* Very selective form of debridement
* Fairly rapid and can debride areas that are difficult to access by other debridement methods<ref name=":0" />
* Appropriate for use on large wound areas<ref name=":1" />


Most studies and anecdotal reports that I've seen say that they discontinue the use of collagenase once the eschar has been eradicated. However, the manufacturer itself says that it is safe and effective in use throughout the wound healing process. And part of that is because of the effectiveness that it has on reducing fibrin and promoting that endothelial activity that was mentioned in the one study.
'''Disadvantages'''


So this picture is just an example of how I have applied collagenase in the past. Because collagenase is an ointment and the wound bed is typically moist, it's very difficult to apply the ointment directly to the wound bed because it just kind of slides around. So we have found it to be much more effective to apply the collagenase to the dressing, such as the multiple layers of Xeroform or Vaseline gauze, or a foam dressing if you're using that. Applying it in the area of the eschar and then placing that onto the burn wound. Again, since there's not a risk to the viable tissue, you don't have to be extremely precise in where you are applying the collagenase, you just want to be fairly efficient so that you're not wasting the product. And then you dress the entire wound.
* Containment of the larvae, limits application in the outpatient setting
* Patient or caregiver acceptance of the treatment intervention<ref name=":0" />


In the wound pictured here, it can be done in a couple of ways. You can apply the collagenase on the Vaseline-based dressing to the eschar, and then apply Vaseline dressing to the entire wound bed without the debriding agent and change that entire wound daily. Or you can apply a dressing that can be used for an extended period of time, a silver foam, a regular foam that can be left on for several days at a time and place that dressing around the eschar. Place the collagenase and whatever dressing you're using to hold that collagenase in place on the eschar, and then bandage the entire hand. And then in 24 hours you can remove the outer gauze wrap, change the collagenase, but leave the dressing intact on the viable parts of that burned hand and then redress, reapply the collagenase and redress that hand wound. That decreases the dressing change and trauma to the areas that are continuing to heal, but still provides effective and safe management of the eschar using collagenase as the primary debriding mechanism.


The bromelain-based enzyme has also undergone extensive studies. A compilation of the study results have found that after pre-soaking and applying the enzyme for four hours, followed by mechanical debridement and soaking overnight, a skin graft has an 86% rate of effectiveness once that wound, that skin graft has been applied after that overnight soaking. It also found that burns treated with the bromelain-based product usually only require one four-hour application to be successful in removing all of the eschar. It has contributed to fewer surgeries and smaller skin graft areas, which results in decreased blood loss and decreased time to complete eschar removal on the surface of that burn wound, and it found that there was no difference in the quality of the scar following debridement using the bromelain-based agent versus conventional surgical excision. It also found that early application, in these studies early application was within 12 to 72 hours of the injury is the gold standard. Delays greater than 72 hours should be managed, as I said before, first assuring that there's no infection, and then pre-soaking to soften that eschar before application of the enzyme.
This ''optional'' video overviews the evidence supporting the use of maggot therapy in wound care.
{{#ev:youtube|2K_m8Ad4HOw|500}}<ref>YouTube. Maggot Therapy for Treating Wounds. Available from: https://www.youtube.com/watch?v=2K_m8Ad4HOw [last accessed 30/July/2023]</ref>


It was also found to be effective in reducing the need for an escharotomy if applied early enough. If the compartment syndrome had already become established and there were already high pressures in those compartments, then a surgical escharotomy was indicated. But if the compartments were still somewhat soft, but the patient was noted to be at significant risk of developing one, then application of the bromelain-based enzyme could eliminate the need for that escharotomy. Other studies show that one treatment of four hours, followed by a two-hour soaking, resulted in complete eschar removal of deep partial and full thickness burn wounds. This was a small animal study. Another one showed that after eschar removal, a skin graft should be delayed for two days. That is a recommendation of the consensus panel that presented several of these guidelines.  
=== Enzymatic Debridement ===
<blockquote>Enzymatic debridement "uses naturally occurring proteolytic enzymes or proteinases, which can aid in the wound repair process. These enzymes remove devitalized tissue by digesting and dissolving the non-viable tissue and thus chemically liquefying non-viable tissues within the wound bed."<ref>Wound Source. Enzymatic Debridement: How Does it Work?. Available from: https://www.woundsource.com/blog/enzymatic-debridement-how-does-it-work (accessed 30/July/2023).</ref></blockquote>This is a highly studied form of non-surgical debridement,<ref name=":0" /> and there is an extensive evidence base to support its use. At the time of writing, there are two products approved for medical use in the United States, Collagenase and NexoBrid, which will be discussed below.  


There are also precautions that should be considered when using the bromelain-based enzyme. For one thing, it has not been studied in large surface area burn wounds as far as applying the product all at once. As I said, most of the recommendations are 15% TBSA or less. So if you have a larger burn, then you need to apply it in sequential parts of 15% to achieve that complete debridement. It has also not been studied on chemical burns, so there's no known effect for that. They have found poor results in using the bromelain-based enzyme on early application for scald burns and in applying it to burn wounds on the surface of diabetic feet. And that needs further study because they're not really sure why those results are so poor. It's also not recommended for high-voltage electrical injuries or the established compartment syndromes, as I'd said before.
'''Contraindications'''


As for the procedure for applying the NexoBrid to eschar in a burn wound, most of what I'm going to list has come from various studies, the consensus recommendations, and case reports. The insert that's included with NexoBrid from the manufacturer has very little detail as far as the application instructions. The main thing it does say is that the patient needs to be an inpatient when using NexoBrid for burn wound debridement, and it should be either in a burn unit or a burn centre, if at all possible.
* A relative contraindication is use in heavily infected wounds
* ''Collagenase'' should not be used in conjunction with silver-based products or with Dakin solution.<ref name=":0" /><ref name=":1" />
* ''NexoBrid'' safety and effectiveness have not been established on:
** chemical or electrical burns<ref name=":0" /><ref name=":3">Nexobrid. Highlights of Prescribing Information. Available from: https://www.nexobrid-us.com/pdf/nexobrid-full-prescribing-information.pdf (accessed 29/July/2023).</ref>
** burns on the face<ref name=":0" /><ref name=":3" />
** burns on the perineum or genitalia<ref name=":3" />
** burns on the feet of patients with diabetes mellitus<ref name=":0" /><ref name=":3" />
** burns on the feet of patients with occlusive vascular disease<ref name=":3" />
** circumferential burns<ref name=":3" />
** burns in patients with significant cardiopulmonary disease (including burn inhalation injuries)<ref name=":3" />
** established compartment syndromes<ref name=":0" />


So the procedure is a combination of the insert as well as the insert of the manufacturer's recommendations as well as the consensus and some of the studies that I found. The current recommendations are that it should be only applied to an area of 15% total body surface area or less per application. It should be applied by a skilled practitioner such as an MD (medical doctor) or a nurse practitioner or a physician's assistant, usually in the operating room. The patient needs to have adequate pain medication during the application process and for the entire four hours that the enzyme is in contact with their burn wound. It's important to protect the peri-wound skin with a thick layer of petroleum or some other skin protectant to prevent maceration and to prevent burning of the NexoBrid on the skin, although it doesn't destroy or damage the skin, it can cause some burning and maceration. It should be applied in a thick layer and then covered with an occlusive dressing. It should not be used in combination with Silvadine or Betadine. And it should stay in place for four hours. At four hours the dressing is removed. There are some studies that showed performing mechanical cleaning or wet-to-dry dressings for a short period after removal of the NexoBrid dressing will help remove the residual non-viable tissue and the residual product that stays on the wound after that dressing has been removed.  
* ''NexoBrid'' should NOT be used in patients with uncontrolled disorders of coagulation<ref name=":3" />
* ''NexoBrid'' can be used WITH CAUTION in patients on anticoagulant therapy or other medications which affect coagulation, and in patients with low platelet counts and "increased risk of bleeding from other causes."<ref name=":3" />


Then the wound bed needs to be assessed. If there is punctate bleeding, just little spots of bleeding throughout that burn eschar, then the burn is expected to re-epithelialise without the need of a skin graft. If there is more large-calibre vessel bleeding when that dressing is removed, then there is indication that a skin graft is needed to help complete the wound healing process. If a skin graft is not determined to be necessary at that particular time, then dressings are used to provide the moist wound environment for healing to continue. That can be allografts, if the resources are available, or some other form of skin substitute or dressings that your facility uses for ongoing burn care, preferably ones that can be left in place for several days at a time, so you're not disturbing that burn wound and the healing process can continue. If a skin graft is indicated, some studies or the consensus panel recommend a delay of two days to allow that burn wound to stabilise for the vascular granulation tissue surface to become more stable, so it will be ready to accept the skin graft.


There has been some off-label use of NexoBrid reported in the literature, including applying it up to 30% total body surface area in one application without adverse effects. And a study that showed it could be used in the outpatient setting, although it's only approved for inpatient use, in a very small burn wound with adequate pain medication. The recommendations for when it's appropriate to apply a skin graft vary from immediately after that NexoBrid dressing is removed to the delay of up to two days to allow that wound bed to become a little bit more stable.
{| class="wikitable"
|+
!
!'''Enzyme'''
!'''Basic Application Procedure'''
!'''Special Considerations'''
|-
|[https://santyl.com/hcp '''Collagenase''']
|
* Derived from the fermentation by ''Clostridium histolyticum.''<ref name=":0" /><ref name=":2">Santyl. Collagenase. Available from: https://santyl.com/sites/default/files/2019-12/SANTYL-PI.pdf (accessed 29/July/2023).</ref>
* Possesses the unique ability to digest collagen in necrotic tissue.
|
'''According to the Santyl website:'''


I do want to point out that there is another bromelain-based debriding agent on the market under the name of EscharEX. It's produced by the same manufacturer that produces NexoBrid, but it is indicated for non-burn wounds, those chronic hard-to-heal wounds like diabetic foot ulcers, venous leg ulcers where NexoBrid is indicated specifically for burn injuries. I just wanted you to be aware of that in case you hear the other name and are wondering what the differences are.  
# Prior to Collagenase application, the wound should be cleansed of debris and digested material by gently rubbing with a gauze pad saturated with normal saline solution, then rinsed with normal saline solution.<ref name=":2" />
# If infection is present, an appropriate antibiotic powder should be applied to the wound to the wound before applying Collagenase. However, if the infection is not responding, enzymatic debridement treatments should be discontinued until the infection clears.<ref name=":2" />
# Collagenase may be applied directly to the wound or to a sterile gauze pad, which is then applied to the wound and properly secured.<ref name=":2" /> A vaseline-coated gauze, such as Xeroform or Vaseline gauze, can also be used in multiple layers to maintain the necessary moisture in the dressing.<ref name=":0" />
# Use of Collagenase should be discontinued when debridement of devitalised tissue is complete and granulation tissue is well established.<ref name=":2" />
|
* Requires daily dressing changes.<ref name=":0" /><ref name=":2" />
* It is not recommended to leave it on for more than 24 hours at a time.<ref name=":0" />
* When clinically appropriate, crosshatch thick eschar with a #10 scalpel blade to increase the surface area contact of the ointment with necrotic debris.<ref name=":2" />
|-
|[https://www.nexobrid-us.com '''NexoBrid''']
|
* A mixture of bromelain-based proteolytic enzymes extracted from the stems of pineapple plants.<ref name=":3" />
|'''According to the NexoBrid website:'''
# Thoroughly clean the wound and apply a dressing soaked with an antibacterial solution to the treatment area for at least 2 hours.
# Afterwards, ensure the wound bed is clear of any  topical agent remnants (e.g. silver sulfadiazine or povidone iodine).
# Apply an ointment skin protectant (e.g., petrolatum) 2-3 cm outside of the treatment area to create a skin barrier.
# Protect any open wounds (e.g., laceration, abraded skin and escharotomy incision) with skin protectant ointments or ointment gauze.
# Moisten the burn wound treatment area with 0.9% Sodium Chloride.
# Using a sterile tongue depressor, completely cover the moistened treatment area with a 3-mm thick layer. Only cover the burn wound area (avoid the periwound area).
# Cover the treated wound with a sterile occlusive film dressing.
# Cover the dressed wound with a sterile loose, thick, fluffy dressing and secure with a sterile bandage.
# Leave in place for 4 hours.


So for large surface area burns, patients in critical condition, established compartment syndromes, surgery remains the standard of care. But as we've seen, there are many situations when surgery may not be indicated or feasible at a particular time or even throughout the course of healing. And so non-surgical interventions are very appropriate in these situations. Those patients who are unstable, burns that are very small and can be managed locally very effectively, or those burns of mixed depth where a wide surgical excision can cause more damage to salvageable tissue, and thereby waiting for those less severe burns to heal using non-surgical interventions can be beneficial, so that surgery can focus on just those deep areas when they become more well defined. Surgical excision may also not be the best intervention for certain areas of burn. Those areas that are difficult to access, deep skin folds, deep in the perineum, or those areas that can be damaged further by aggressive surgical intervention or with cosmetic concerns such as the hands and the face.
'''After 4-hours:'''


So non-surgical debridement with a combination of those non-surgical methods can be very effective. It's very common to use a dressing that promotes autolysis and at each dressing change, perform mechanical debridement, and even local sharp debridement to further debride the non-viable tissue and eschar from that burn wound. It's a slower process, but it can be very effective in removing areas of eschar under those smaller dressings. Collagenase can also be combined with an autolytic-type dressing. It's important to remember that that is a daily dressing change, so the dressing you choose should be appropriate for a daily change as far as cost goes and time management, so those Vaseline-coated gauzes in multiple layers that can provide a somewhat occlusive covering will facilitate the work of collagenase much more effectively.
# Remove the occlusive film dressing using an aseptic technique and remove the ointment barrier using a sterile, blunt-edged instrument.
# Remove the dissolved eschar from the burn wound by scraping it away with a sterile, blunt-edged instrument.  To remove remnants of dissolved eschar, apply a dressing soaked with an antibacterial solution for at least 2 hours.
# Wipe the wound thoroughly with a large sterile dry gauze, then repeat with a sterile gauze soaked with sterile 0.9% Sodium Chloride. Rub the treated area until the wound bed has the appearance of "clean dermis or subcutaneous tissues with pinpoint bleeding".<ref name=":3" />
|
* NexoBrid should be applied in hospital settings by a medical doctor, physician's assistant or nurse practitioner.
* Begin pain control measures at least 15 minutes prior to NexoBrid application and maintain proper pain management throughout the treatment.


Santyl is, as I said, the only collagenase-based debriding agent currently on the market. It is slower compared to the other methods of debridement that we've discussed, particularly surgical excision or the bromelain-based enzyme. However, it's very appropriate to be used at bedside or in the outpatient setting, so it does not require that excessive pain medication, and it can be applied by a family member or a caregiver after instructions so that these dressing changes can continue at home in between visits to the outpatient setting.
* If the burn wound area is greater than 15% total body surface area, apply in two separate sessions.
* Apply the second application 24 hours after the first application to the same or new burn wound area.
* The total treatment area must not exceed 20% total body surface area across two treatment sessions.<ref name=":3" />
|}


NexoBrid remains the only bromelain-based debriding agent on the market. The main disadvantages of NexoBrid are that the patient needs to be hospitalised. They need to have significant pain medication administered during the application process of NexoBrid, and the application is generally limited to a surface area of less than 15% total body surface area. So for larger burns, it requires multiple applications in different sections on consecutive days to achieve complete debridement of that burn wound. There is an off-label report that shows safe use of bromelain on a surface area up to 30%, but that remains off-label, and the consensus guidelines still limit the use of bromelain to the 15% total body surface area.
''The above procedure lists are based on instructions found on the drug manufacturer's websites. Please study and review the manufacturer's information and attend hands-on training prior to using as indicated. Please review your discipline's practice act before performing any type of debridement.''


The advantages are that it only requires a single application in most cases to achieve complete removal of the eschar. There have been some times when the eschar is not completely eradicated and repeat application to the same area is not recommended, except in very certain circumstances, and currently it does require a skilled clinician, a physician, or a mid-level to apply this in the inpatient setting.


The greatest benefits of the bromelain-based product is that it does achieve 100% removal of the eschar in most cases, and it allows for immediate, or very shortly thereafter, skin grafting to that area if a skin graft is indicated. There are some reports that say a delay of two days is preferable to allow that wound bed to become stable before a skin graft is applied. And there are documented procedures that show the benefits of mechanical debridement, a scrubbing, or a wet-to-dry dressing immediately after the removal of the NexoBrid dressing to allow that wound to be cleaned up to remove any residual necrotic tissue that remains on the surface of the wound to remove the remaining product that remains on the surface of the wound before that skin graft is applied. And in those situations where a skin graft isn't indicated, then it prepares that wound bed for another temporary coverage. An allograft or another type of skin substitute or even ongoing dressing changes until that burn wound goes on to heal or the area that needs skin graft is small enough and a smaller skin graft can be applied.
'''Advantages'''


So the biggest benefits for non-surgical debridement include the elimination for the need of a skin graft or a decrease in the size of the skin graft that is needed, which also decreases the size of the donor site. It also allows for ongoing therapy to limit the negative effects of having to immobilise a body part after a skin graft. You can continue with occupational therapy and physical therapy throughout the healing course, which decreases the long-term comorbidities and recovery. The rapid removal of eschar decreases the risk of infection and also decreases the length of hospitalisation. Now, surgery is obviously the most rapid way to remove that eschar, but as I've said with these smaller situations where surgery may not be indicated, the combination of non-surgical debridement interventions can also remove that eschar fairly rapidly and can be done on an outpatient basis if it's a smaller burn and the patient is stable.
* Less aggressive form of debridement compared to surgical options
* Faster results than autolytic debridement  
** NexoBrid has faster results than Collagenase. When applied correctly, it can remove 100% eschar with a single application<ref name=":4">Pertea M, et al.  [https://www.mdpi.com/2076-3417/11/17/8134 Efficiency of Bromelain-enriched enzyme mixture (NexobridTM) in the treatment of burn wounds].  Appl Sci, 2021; 11, 8134.</ref>
* Very selective form of debridement<ref name=":4" />
* Reported to be the most cost-effective debridement method, with a shorter duration of treatment and fewer clinical visits compared to other types of debridement<ref name=":5" />
* Can be beneficial and an effective adjunct to surgical excision
* Good alternative to surgery in areas that are difficult to debride (deep skin folds, fingers, hands), and areas where cosmesis and function are important (e.g. face, neck, hands)
* ''Collagenase'' use produces minimal pain
* ''Collagenase'' has a simple application, can easily be utilised at the patient bedside, outpatient or home setting<ref name=":0" />


So non-surgical debridement has been found to be very safe and effective on smaller burns, management of patients when surgery isn't indicated or not appropriate. Those large burns where they will epithelialise within a three-week time don't necessarily need to go to surgery for any reason, they can be managed locally. Severe hand burns, where the damage from surgery can cause long-term functional problems when they're managed locally with non-surgical interventions, some of those problems can be avoided. And a combination of methods has been found to provide a significant improvement in the efficiency of the non-surgical debridement and the gradual removal of that eschar.
'''Disadvantages'''


So this particular picture shows the initial burn wound and after seven days of application with collagenase, the improvement in that burn wound with significant re-epithelialisation and a remaining burn in the centre that can continue to granulate and allow further epithelialisation. However, in all cases, if the burn has not fully re-epithelialised within 21 days, then most experts agree that a skin graft is essential to limit the comorbidities of allowing that wound to go on and heal secondarily, such as dysfunctional scarring, contractures, and that ongoing risk of infection with that open wound. So in both cases, with these photos, allowing the outer areas to re-epithelialise definitely decreases the area that will need surgical intervention if they don't continue to re-epithelialise completely within that 21-day timeframe.
* Not effective or adequate for severe deep burns or critical patients
* Can cause maceration to periwound tissue<ref name=":0" />
* ''NexoBrid'' use requires hospitalisation - it is only appropriate for use on inpatients
** treatments are painful, and analgesia and/or anaesthesia are required during use<ref name=":0" /><ref name=":3" />
** requires medical doctor/physician's assistant/nurse practitioner to apply and monitor the patient during use, preferably in a Burn Unit or at a Burn Centre
** risk of bleeding during use
** can only apply to a total body surface area of 15% or less at a time<ref name=":3" />


=== Other Agents to Facilitate Debridement ===
== Conclusion ==
There are other reports out there of using agents that are not specifically intended for debridement to facilitate debridement. One of those is medical grade honey. Because medical grade honey puts the wound in an increased pH where bacteria don't like to thrive and it adds that moist environment to the wound bed, then a lot of people use medical grade honey to facilitate the local sharp debridement and mechanical debridement that they do at each dressing change. So you may hear about medical grade honey in the realm of debriding, the burn wound, but it is not specifically a debriding agent.  
Several evidence-supported non-surgical debridement methods are available for treating burn wound injuries. While, in general, these debridement methods require more time to fully remove devitalised tissue from a burn wound, they do so with less trauma and bleeding risk to the surviving tissue. These techniques can be used alone or in combination with the ultimate goal of creating a clean wound bed ready for healing and closure.
 
One of the greatest benefits of non-surgical debridement is the elimination of the need for a skin graft or a decrease in the size of a skin graft for wound closure. This means there is also a smaller or no donor site. Related benefits include uninterrupted and/or unmodified occupational and physiotherapy to continue throughout the healing process. The functional gains and continued independence for the patient healing from a burn wound are key to their mental health and motivation for future interventions.  


== Resources  ==
== Resources  ==
*bulleted list
*x
or


#numbered list
==== Optional Additional Reading ====
#x
 
* Heitzmann W, Fuchs PC, Schiefer JL. [https://www.mdpi.com/1648-9144/56/12/706 Historical perspectives on the development of current standards of care for enzymatic debridement]. Medicina. 2020 Dec 17;56(12):706.
* Thomas DC, Tsu CL, Nain RA, Arsat N, Fun SS, Lah NA. [https://pdf.sciencedirectassets.com/305626/1-s2.0-S2049080121X00118/1-s2.0-S2049080121008268/main.pdf?X-Amz-Security-Token=IQoJb3JpZ2luX2VjEBMaCXVzLWVhc3QtMSJIMEYCIQDXqZvB0qV%2B1G8Pq%2BbhL9eb8JKvZ293Xn%2Fi29FYhFwtuAIhAIof6tjK25D4MwYZk4%2BfDR5BcONqDAEGVAdHj%2FrMoCe4KrsFCKv%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEQBRoMMDU5MDAzNTQ2ODY1IgzI2t5o9ekMQn5LWm0qjwW%2BQFe1PjXh1X5TY195mYBno01j%2FF4P8M%2ByvkszSkgXE2iVs6fQ1Cc6vPEDfSBbGBYSrlttnDipKUisL4Xulbq6Qk7865d2rxBq%2BQdQ5%2BoptSbJcInNO%2F2%2Fo7fMBRBpagczrtYzAjr7N1mwwEAFW4IjlpgRVepCilRQvY6guwi3GomErfl78HhnABL4CfqhAG6adUNzq9SjaGA4vV0DeXNr3pN4Zp%2BtCd5aqLzGXhQiQ5kxSsr2IfaLnggjaEO4X04Gnl6MuxxTcqS7aCaN%2FQfdk0LktHVhmhBcrwIg%2Fq8jAniUCx52A2JNnUJhRnObP3MXGD2dIdJj39Nehmt0ixKJKF6yhwa8dMfhG93Cuv1eew8SQEZIld%2FSqcidfKmiiiL%2F24TQlOEXDi3anumxpnvqg29zxPxHVTOx8PwcSWp6Hme8ic7GtlxVlCI6ZnLeR9JPib4yCkGnhzkaBRKzG08PstI7bR4Xj%2BMxP7e5Exnuj8QYhMo00jOy%2BA3SuXje%2FAWSc9M%2Fp2Ad6b5SUXVLgjweC%2FpL%2BSAfp%2Bl%2FDX6g6xsWXdODWdYWPhLX0tp%2BS3Seju%2Fa3doEyuLLppfKZgSWWSOZe7IoRoJO7pGXZ%2BvO%2BdDYBPzgdTSeUehCv7PWXfiomMXO3bLLpNaCOcxb93Zm0Wy6YosGKc6kcS1d8CaIcC2aEdfivkQ%2B2baJN43v6XoafNKWAvOHgGTDvAIchbhX4qlWRwfisUHhhRxEtaMJ%2FEKlho9IIWhQ7rXl1U3lhqFIhaS0SNxdHofg4O%2Blt7cUAz2%2BZkqwEM3gKATQ9NzHc3QOgTj40LR3w1%2FC9FXG8EJ0BOorBejZ7hejs1agc6z%2BJ5olbAKCm5SxgvqCz71wgeMvMKDMmqYGOrABWJNKu4TFMvTGnIaBxuO91P1JjAXAP89TIpCkG3ImZvn3srVwyM%2FeaAYufW74r86BxNgaB26cgEoTN09M9brp69krIrpnJzRRXUNhjfgLdfldqBRD2zTRb9xI0Vwf3hb4XFf4Ch7LeN%2BfXhHZdHsvd22%2B755qvMI%2BINbYLDQRxuH4gGkQJCAiDjXrPsGO6YFgwVpjL71CuZxiQkLCsMfCOWLlaM2U137LH8MFvoZS0NU%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20230730T185142Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY3X57FJD4%2F20230730%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=06c7254c4a36c3866aa178e8f4f54fb9db667b84310acf8f458fb8468746bea9&hash=236ac90576b00b8760fee49338ba29c1af7b632fe160445ba8c387ef2fd92ff1&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S2049080121008268&tid=spdf-6eb7c185-2d48-4dd1-a284-355576294bb2&sid=d43c74572cc9d14358480c1379e5bede925agxrqa&type=client&tsoh=d3d3LnNjaWVuY2VkaXJlY3QuY29t&ua=1312570a0b04060c5258&rr=7eefcb687956aa49&cc=us The role of debridement in wound bed preparation in chronic wound: A narrative review]. Annals of medicine and surgery. 2021 Nov 1;71:102876.
 
==== Optional Additional Video ====
Expand your knowledge of this related topic, compartment syndrome, by viewing this 5-minute video.
{{#ev:youtube|oO9GqanB0s8|500}}<ref>YouTube. Compartment Syndrome, Animation.  Available from: https://www.youtube.com/watch?v=oO9GqanB0s8 [last accessed 30/July/2023]</ref>


== References  ==
== References  ==


<references />
<references />
[[Category:SRSHS Course Pages]]
[[Category:Course Pages]]
[[Category:Burns]]

Latest revision as of 01:36, 11 September 2023

Original Editor - Stacy Schiurring based on the course by Diane Merwarth

Top Contributors - Stacy Schiurring, Jess Bell and Matt Huey

Introduction[edit | edit source]

Burn wound injuries are a common injury worldwide. Burn wound therapy continues to be a challenging and dynamic field of medicine and rehabilitation. The first and most critical step in burn wound care and wound bed preparation is the removal of eschar and other non-vitalised tissue. This helps to reduce the bioburden and potential for biofilm formation in the wound, minimises the risk for infection and compartment syndromes, and promotes healthy granulation and wound healing.[1][2]

Since the 1970s, early surgical excision and debridement of burn wounds have been the standard of care. Surgical debridement can quickly and fully remove non-viable and necrotic tissue from a burn wound. However, it has the disadvantages of causing huge trauma, excessive bleeding, and being very non-selective in the removal of unwanted tissue in the burned area. Alternative non-surgical methods of debridement have been explored and researched. These methods provide less invasive and more selective options for the removal of non-vitalised tissue from a burn wound.[2]

This article will explore five methods of non-surgical debridement: (1) mechanical, (2) autolytic, (3) local sharp, (4) biosurgical, and (5) enzymatic.

Please see this article for a list of useful wound care terminology.

Indications for Debridement[edit | edit source]

Indications for debridement:[3][2]

  • Remove devitalised tissue. This is the primary function of debridement.[4] The presence of non-living tissue in a wound bed impedes wound healing by:
    • acting as a nutrient source and an ideal living environment for unwanted microbes which can cause infection
    • creating a physical barrier for re-epithelialisation
    • creating a barrier against topical antimicrobial agents, which limits their ability to manage infection in the wound
  • Stimulate the wound bed in chronic wounds to reinvigorate the wound healing cascade.[4] The presence of non-living tissue in a wound bed affects the wound healing cascade by inhibiting:
    • angiogenesis (the formation of new blood vessels from existing vasculature)
    • granulation tissue formation
    • re-epithelialisation

Surgical excision of non-viable tissue is the standard of care. However, there are times when less aggressive debridement methods are required, including the following:[3]

  1. Medically unstable patients who would not tolerate sedation and/or surgical interventions
  2. When surgical resources are not available
  3. Non-surgical management is preferred
  4. Areas of deep partial and full thickness injury are small and can be properly managed with less invasive methods
  5. The area of the burn wound injuries is not serious enough to warrant surgery
  6. The risk of surgery damaging vital structures is greater than non-surgical care, such as on the fingers or hands

Clinical Pearls: a deeper look at eschar[edit | edit source]

Burn wound injuries lead to the formation of a non-viable tissue called eschar. Similar to burn classification, the depth of eschar in a wound bed may be superficial or deep. The presence of any non-viable tissue, including eschar, in a burn wound bed, serves as a base for bacterial growth and may result in an inflammatory response, which can contribute to the extension of the burn wound injury. It also creates the potential for local and systemic infection. Therefore, the removal of eschar is a primary focus of burn wound therapy.[5]

According to a study by Gurfinkel et al.,[5] the initial diagnosis of the extent of the eschar within the wound bed is the first step in any debridement strategy. Unfortunately, assessing burn wound depth through the opaque eschar is "difficult, if not impossible." Furthermore, the depth of a burn injury can be inconsistent throughout the damaged area. The colour and texture of the eschar found within a burn wound can be misleading even to wound care experts. Very often, the extent and depth of tissue damage may only be determined days after injury when the secondary damage has already extended beyond the original burn wound.[5]

Keep this information in mind as you continue to learn about the types of non-surgical debridement. Consider how a more selective form of debridement can spare tissue which has the potential to heal, and would limit the amount of ongoing tissue trauma which occurs following a burn wound injury. What psychological effect could this have on a patient following a burn wound injury?

Non-surgical Debridement[edit | edit source]

Non-surgical debridement is the removal of materials which limit or impair healing from a wound bed by means other than sharp excisional methods into viable tissue in a sterile surgical setting. Examples of unwanted materials in a wound can include eschar, necrotic tissue, bioburden, biofilm, or foreign matter.

Mechanical Debridement[edit | edit source]

"Mechanical debridement is a nonselective type of debridement, meaning that it will remove both devitalized tissue and debris and viable tissue. It is usually carried out using mechanical force."[4]

The amount of force applied during mechanical debridement is subjective and is based on the wound care professional's clinical skill and comfort level. Currently, there is little evidence in the literature to support the use of mechanical debridement in the treatment of burn wound injuries.[3]

Indications for mechanical debridement:

  • acute and chronic wounds with moderate to large amounts of non-viable tissue
  • can be used regardless of the presence of active infection[4]

Contraindications for mechanical debridement:

  • greater percentage of granulation tissue than devitalised tissue in the wound bed
  • inability to control pain
  • patients with poor perfusion[4]


Examples of mechanical debridement:

  1. Pulsatile lavage. Involves moderate-to-high pressure irrigation, which is well controlled and known to be safe for the surface of wounds, including burn wounds.[6]
  2. Wound Irrigation. Can be achieved using a syringe with a known gauge needle to provide a known amount of pressure. Not commonly effective for use in burn wound injuries.
  3. Shower. Please see this article for more information.
  4. Whirlpool. Please see this article for more information, especially regarding the physiological responses and risks of whirlpool use with burn injuries.
  5. Scraping. Achieved using the edge of a scalpel, a curette, or some other flat instrument, such as a tongue blade, to scrape the surface of the burn wound and remove any loosened debris.
  6. Wet-to-dry dressings. Involves applying gauze which has been moistened with either saline or an antimicrobial agent on to the surface of the burn wound, allowing the gauze to dry, then removing it from the burn wound surface. As the gauze dries, anything on the wound surface, including loosened devitalised tissue or healthy granulation tissue, can adhere to the gauze. When the gauze is removed, both types of tissue are ripped off the wound surface. This method of debridement can be very painful and highly non-selective.
  7. Soak and wipe. Involves applying towels or gauze saturated with saline or an antimicrobial solution to the surface of the burn wound and allowing them to "soak" for 5-10 minutes. Next, using a saturated gauze, wipe the wound surface with an applied force in circular motions to remove debris. The wiping is performed to the patient's tolerance. Caution should be taken to only use clean gauze when wiping, and discard gauze as it collects devitalised tissue. When treating a large burn wound, only expose a small area at a time to prevent hypothermia. Please see this article for more information.


Advantages

  • Quick to perform with appropriate pain management
  • Can be used with active infection
  • Efficient for larger wounds
  • Effective at the bedside or in the outpatient setting with adequate pain management

Disadvantages

  • Very non-selective form of debridement
  • Very painful

Autolytic Debridement[edit | edit source]

"[Autolytic] debridement is a natural process by which endogenous phagocytic cells and proteolytic enzymes break down necrotic tissue. It is a highly selective process whereby only necrotic tissue will be affected in the debridement."[4]

This is the most conservative type of debridement. Autolytic debridement involves dissolving or separating eschar from the underlying dermis to allow it to be removed or debrided away. A moist dressing environment optimises autolytic debridement.[3] The effectiveness of autolytic debridement depends upon the amount of devitalised tissue present in the wound and the true wound size.[1][4]

Indications

  • Recommended for non-infected wounds.[3][4] However, it can be used with other debridement techniques, such as mechanical debridement, if wounds are infected.[4]

Contraindications

  • Immuno-compromised patients[4]


Examples of dressings that facilitate autolytic debridement:

  1. Hydrocolloids (most effective)
  2. Hydrogels
  3. Transparent films
  4. Medical grade honey[3]


Advantages

  • Very selective because it only targets the necrotic tissue
  • Essentially painless
  • Fairly simple process to utilise[3]

Disadvantages

  • Slow debridement process when compared to other methods
  • Not indicated in the presence of an active infection
  • Not effective or efficient for use in burn wounds with large surface areas[3]

Local Sharp Debridement[edit | edit source]

"Devitalized tissue (slough, necrotic, or eschar) in the presence of underlying infection is removed using sharp instruments."[4]

Tools that can be used for local sharp debridement include a scalpel,[3][4] scissors,[3] and/or curettes.[4] Local sharp debridement is performed by a skilled clinician with wound specialist training. In order to safely perform local sharp debridement, wound care professionals must be able to distinguish between tissue types and have a good understanding of functional anatomy as this procedure carries the risk of damage to blood vessels, nerves, and tendons.[1]

Indications

  • Recommended for infected wounds
  • Can be combined with all the other debridement methods[4]

Contraindications

  • Patients on anticoagulation therapy due to bleeding risk[3]
  • Intact eschar and no clinical evidence of an underlying infection[4]

Advantages

  • Can be fairly quick
  • Very specific form of debridement
  • Good method for bedside or outpatient procedures[3]

Disadvantages

  • Can be painful[3]
  • Can be an invasive procedure, depending on the depth of debridement[4]
  • This technique requires specialised training, certification, and/or licensure.[3] Please review your local practice act and complete appropriate and required training before performing local sharp debridement as part of a wound care treatment plan.

Biological Debridement[edit | edit source]

Biological debridement (larval therapy, maggot therapy, biosurgery) uses sterile larvae of the green bottle fly to debride devitalised tissue. This is done via the release of proteolytic enzymes from larvae secretions and excretions, which dissolve necrotic tissue from the wound bed.[4]

The larvae are applied directly to the wound bed and can be either enclosed and contained in a "biological bag" or "free-range." Research has shown that biological debridement performed by free-range larvae is twice as fast as those enclosed in the biological bag.[4]

Other benefits of biological debridement include:[4][7]

  1. Bactericidal because the larvae ingest and digest bacteria
  2. Inhibiting bacterial growth by releasing ammonia into the wound bed, which increases the pH of the wound
  3. Breaking down existing biofilm at the wound bed and inhibiting new biofilm growth
  4. Direct ingestion of necrotic tissue


Advantages

  • Essentially painless[4]
  • Very selective form of debridement
  • Fairly rapid and can debride areas that are difficult to access by other debridement methods[3]
  • Appropriate for use on large wound areas[4]

Disadvantages

  • Containment of the larvae, limits application in the outpatient setting
  • Patient or caregiver acceptance of the treatment intervention[3]


This optional video overviews the evidence supporting the use of maggot therapy in wound care.

[8]

Enzymatic Debridement[edit | edit source]

Enzymatic debridement "uses naturally occurring proteolytic enzymes or proteinases, which can aid in the wound repair process. These enzymes remove devitalized tissue by digesting and dissolving the non-viable tissue and thus chemically liquefying non-viable tissues within the wound bed."[9]

This is a highly studied form of non-surgical debridement,[3] and there is an extensive evidence base to support its use. At the time of writing, there are two products approved for medical use in the United States, Collagenase and NexoBrid, which will be discussed below.

Contraindications

  • A relative contraindication is use in heavily infected wounds
  • Collagenase should not be used in conjunction with silver-based products or with Dakin solution.[3][4]
  • NexoBrid safety and effectiveness have not been established on:
    • chemical or electrical burns[3][10]
    • burns on the face[3][10]
    • burns on the perineum or genitalia[10]
    • burns on the feet of patients with diabetes mellitus[3][10]
    • burns on the feet of patients with occlusive vascular disease[10]
    • circumferential burns[10]
    • burns in patients with significant cardiopulmonary disease (including burn inhalation injuries)[10]
    • established compartment syndromes[3]
  • NexoBrid should NOT be used in patients with uncontrolled disorders of coagulation[10]
  • NexoBrid can be used WITH CAUTION in patients on anticoagulant therapy or other medications which affect coagulation, and in patients with low platelet counts and "increased risk of bleeding from other causes."[10]


Enzyme Basic Application Procedure Special Considerations
Collagenase
  • Derived from the fermentation by Clostridium histolyticum.[3][11]
  • Possesses the unique ability to digest collagen in necrotic tissue.

According to the Santyl website:

  1. Prior to Collagenase application, the wound should be cleansed of debris and digested material by gently rubbing with a gauze pad saturated with normal saline solution, then rinsed with normal saline solution.[11]
  2. If infection is present, an appropriate antibiotic powder should be applied to the wound to the wound before applying Collagenase. However, if the infection is not responding, enzymatic debridement treatments should be discontinued until the infection clears.[11]
  3. Collagenase may be applied directly to the wound or to a sterile gauze pad, which is then applied to the wound and properly secured.[11] A vaseline-coated gauze, such as Xeroform or Vaseline gauze, can also be used in multiple layers to maintain the necessary moisture in the dressing.[3]
  4. Use of Collagenase should be discontinued when debridement of devitalised tissue is complete and granulation tissue is well established.[11]
  • Requires daily dressing changes.[3][11]
  • It is not recommended to leave it on for more than 24 hours at a time.[3]
  • When clinically appropriate, crosshatch thick eschar with a #10 scalpel blade to increase the surface area contact of the ointment with necrotic debris.[11]
NexoBrid
  • A mixture of bromelain-based proteolytic enzymes extracted from the stems of pineapple plants.[10]
 According to the NexoBrid website:
  1. Thoroughly clean the wound and apply a dressing soaked with an antibacterial solution to the treatment area for at least 2 hours.
  2. Afterwards, ensure the wound bed is clear of any topical agent remnants (e.g. silver sulfadiazine or povidone iodine).
  3. Apply an ointment skin protectant (e.g., petrolatum) 2-3 cm outside of the treatment area to create a skin barrier.
  4. Protect any open wounds (e.g., laceration, abraded skin and escharotomy incision) with skin protectant ointments or ointment gauze.
  5. Moisten the burn wound treatment area with 0.9% Sodium Chloride.
  6. Using a sterile tongue depressor, completely cover the moistened treatment area with a 3-mm thick layer. Only cover the burn wound area (avoid the periwound area).
  7. Cover the treated wound with a sterile occlusive film dressing.
  8. Cover the dressed wound with a sterile loose, thick, fluffy dressing and secure with a sterile bandage.
  9. Leave in place for 4 hours.

After 4-hours:

  1. Remove the occlusive film dressing using an aseptic technique and remove the ointment barrier using a sterile, blunt-edged instrument.
  2. Remove the dissolved eschar from the burn wound by scraping it away with a sterile, blunt-edged instrument. To remove remnants of dissolved eschar, apply a dressing soaked with an antibacterial solution for at least 2 hours.
  3. Wipe the wound thoroughly with a large sterile dry gauze, then repeat with a sterile gauze soaked with sterile 0.9% Sodium Chloride. Rub the treated area until the wound bed has the appearance of "clean dermis or subcutaneous tissues with pinpoint bleeding".[10]
  • NexoBrid should be applied in hospital settings by a medical doctor, physician's assistant or nurse practitioner.
  • Begin pain control measures at least 15 minutes prior to NexoBrid application and maintain proper pain management throughout the treatment.
  • If the burn wound area is greater than 15% total body surface area, apply in two separate sessions.
  • Apply the second application 24 hours after the first application to the same or new burn wound area.
  • The total treatment area must not exceed 20% total body surface area across two treatment sessions.[10]

The above procedure lists are based on instructions found on the drug manufacturer's websites. Please study and review the manufacturer's information and attend hands-on training prior to using as indicated. Please review your discipline's practice act before performing any type of debridement.


Advantages

  • Less aggressive form of debridement compared to surgical options
  • Faster results than autolytic debridement
    • NexoBrid has faster results than Collagenase. When applied correctly, it can remove 100% eschar with a single application[12]
  • Very selective form of debridement[12]
  • Reported to be the most cost-effective debridement method, with a shorter duration of treatment and fewer clinical visits compared to other types of debridement[1]
  • Can be beneficial and an effective adjunct to surgical excision
  • Good alternative to surgery in areas that are difficult to debride (deep skin folds, fingers, hands), and areas where cosmesis and function are important (e.g. face, neck, hands)
  • Collagenase use produces minimal pain
  • Collagenase has a simple application, can easily be utilised at the patient bedside, outpatient or home setting[3]

Disadvantages

  • Not effective or adequate for severe deep burns or critical patients
  • Can cause maceration to periwound tissue[3]
  • NexoBrid use requires hospitalisation - it is only appropriate for use on inpatients
    • treatments are painful, and analgesia and/or anaesthesia are required during use[3][10]
    • requires medical doctor/physician's assistant/nurse practitioner to apply and monitor the patient during use, preferably in a Burn Unit or at a Burn Centre
    • risk of bleeding during use
    • can only apply to a total body surface area of 15% or less at a time[10]

Conclusion[edit | edit source]

Several evidence-supported non-surgical debridement methods are available for treating burn wound injuries. While, in general, these debridement methods require more time to fully remove devitalised tissue from a burn wound, they do so with less trauma and bleeding risk to the surviving tissue. These techniques can be used alone or in combination with the ultimate goal of creating a clean wound bed ready for healing and closure.

One of the greatest benefits of non-surgical debridement is the elimination of the need for a skin graft or a decrease in the size of a skin graft for wound closure. This means there is also a smaller or no donor site. Related benefits include uninterrupted and/or unmodified occupational and physiotherapy to continue throughout the healing process. The functional gains and continued independence for the patient healing from a burn wound are key to their mental health and motivation for future interventions.

Resources[edit | edit source]

Optional Additional Reading[edit | edit source]

Optional Additional Video[edit | edit source]

Expand your knowledge of this related topic, compartment syndrome, by viewing this 5-minute video.

[13]

References[edit | edit source]

  1. ↑ 1.0 1.1 1.2 1.3 Thomas DC, Tsu CL, Nain RA, Arsat N, Fun SS, Lah NA. The role of debridement in wound bed preparation in chronic wound: A narrative review. Annals of medicine and surgery. 2021 Nov 1;71:102876.
  2. ↑ 2.0 2.1 2.2 Heitzmann W, Fuchs PC, Schiefer JL. Historical perspectives on the development of current standards of care for enzymatic debridement. Medicina. 2020 Dec 17;56(12):706.
  3. ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20 3.21 3.22 3.23 3.24 3.25 3.26 3.27 3.28 Merwarth, D. Management of Burn Wounds Programme. Non-Surgical Debridement of Burn Injuries. Physioplus. 2023.
  4. ↑ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 4.12 4.13 4.14 4.15 4.16 4.17 4.18 4.19 4.20 4.21 Manna B, Nahirniak P, Morrison CA. Wound Debridement. [Updated 2023 Apr 19]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507882/ last accessed 27/July/2023)
  5. ↑ 5.0 5.1 5.2 Gurfinkel R, Rosenberg L, Cohen S, Cohen A, Barezovsky A, Cagnano E, J Singer A. Histological assessment of tangentially excised burn eschars. Canadian Journal of Plastic Surgery. 2010 Sep;18(3):33-6.
  6. ↑ Wan J, He J, Chen L, Qiu L, Wang F, Chen XL. Retrospective Study from a Single Center on the Efficacy of Pulsed Lavage Following Excision of Burns≥ 30% of the Total Body Surface Area in 63 Patients. Medical Science Monitor: International Medical Journal of Experimental and Clinical Research. 2022;28:e937697-1.
  7. ↑ Margolin L, Gialanella P. Assessment of the antimicrobial properties of maggots. International wound journal. 2010 Jun;7(3):202-4.
  8. ↑ YouTube. Maggot Therapy for Treating Wounds. Available from: https://www.youtube.com/watch?v=2K_m8Ad4HOw [last accessed 30/July/2023]
  9. ↑ Wound Source. Enzymatic Debridement: How Does it Work?. Available from: https://www.woundsource.com/blog/enzymatic-debridement-how-does-it-work (accessed 30/July/2023).
  10. ↑ 10.00 10.01 10.02 10.03 10.04 10.05 10.06 10.07 10.08 10.09 10.10 10.11 10.12 10.13 Nexobrid. Highlights of Prescribing Information. Available from: https://www.nexobrid-us.com/pdf/nexobrid-full-prescribing-information.pdf (accessed 29/July/2023).
  11. ↑ 11.0 11.1 11.2 11.3 11.4 11.5 11.6 Santyl. Collagenase. Available from: https://santyl.com/sites/default/files/2019-12/SANTYL-PI.pdf (accessed 29/July/2023).
  12. ↑ 12.0 12.1 Pertea M, et al.  Efficiency of Bromelain-enriched enzyme mixture (NexobridTM) in the treatment of burn wounds.  Appl Sci, 2021; 11, 8134.
  13. ↑ YouTube. Compartment Syndrome, Animation. Available from: https://www.youtube.com/watch?v=oO9GqanB0s8 [last accessed 30/July/2023]
Retrieved from "https://www.physio-pedia.com/index.php?title=Non-surgical_Debridement_of_Burn_Injuries&oldid=341319"