Key message
We cannot be certain whether removal of dead or infected tissue of surgical wounds or care that is usually provided makes any difference to how long it takes to remove all of the dead tissue from the wound and for the wound to heal.
What did we want to find out?
Following surgery, most surgical wounds heal naturally with no complications. However, complications such as infection can occur, which may result in delayed healing. There are many different methods of removing dead or infected tissue (called debridement), such as surgical removal of the tissue, enzymes (naturally occurring proteins that dissolve the tissue), and mechanical methods (for example, a special dry gauze that is removed when the tissue has stuck to it). We wanted to look at the different ways to remove dead or infected tissue from wounds after surgical operations and find out how they affect the time it takes to remove all of the dead tissue from the wound and for the wound to heal.
What did we do?
We searched medical databases for well-designed studies including people of any age that compared one method of debridement versus a dummy treatment (placebo), no treatment, or another method of debridement after surgery.
What did we find?
We found six studies dating from 1979 to 2014 that compared different types of wound debridement with the way care was usually provided for wounds that had dead tissue within them after surgery. All six studies compared different types of debridement methods or different types of usual care, meaning we could not combine the results. The total number of participants within the studies was 265, and ages of participants ranged from three to 91 years. The studies were carried out in hospitals in China, Denmark, Belgium, and the UK.
Four studies compared a treatment method that promotes the body's natural wound healing process (called autolytic) with different types of usual care. Overall, we found that this method may make little or no difference to how long it takes to remove all of the dead tissue. One study compared an enzyme with usual care, and we found that this method may make little or no difference to how long it takes to remove all of the dead tissue. One study compared different methods of removing dead tissue using surgery (one via 'keyhole' surgery, the other 'normal' surgery). We found that using keyhole surgery to remove the dead tissue may have little or no effect on time for the wound to heal, but we are very uncertain about the results. Only three of the studies (two autolytic and one using an enzyme) reported serious harmful events that led to discontinuation of treatment or hospital admission. There may be no difference in deaths and serious harmful events between the treatment methods.
Overall, all the studies indicated that it is unclear whether any type of wound debridement is better than usual care at reducing time to remove all of the dead tissue, time to complete healing, serious harmful events that led to discontinuation of treatment, or hospital admission.
What are the limitations of the evidence?
Overall, we are very uncertain about the evidence, mainly because the studies had small numbers of people, and did not report the results well. Additionally, five studies used debridement products that are no longer used clinically.
How up to date is the evidence?
We searched for studies published up to October 2021.
Evidence for the effects of different methods of debridement on complete wound debridement and healing of surgical wounds remains unclear. Adequately powered, methodologically robust RCTs evaluating contemporary debridement interventions for surgical wounds are needed to guide clinical decision-making.
Surgical wounds that become infected are often debrided because clinicians believe that removal of this necrotic or infected tissue may expedite wound healing. There are numerous methods of debridement available, but no consensus on which one is most effective for surgical wounds.
To assess the effects of different methods of debridement on the rate of debridement and healing of surgical wounds.
In October 2021, we searched the Cochrane Wounds Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL. To identify additional studies, we searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies, reviews, meta-analyses, and health technology reports. There were no restrictions on language, date of publication, or study setting.
We included randomised controlled trials (RCTs) that enrolled people with a surgical wound that required debridement, and reported time to complete wound debridement or time to wound healing, or both.
Two review authors independently performed study selection, risk of bias assessment using the RoB 1 tool, data extraction, and GRADE assessment of the certainty of evidence.
In this fourth update, we identified one additional study for inclusion. The review now includes six studies, with 265 participants, aged three to 91 years. Five studies were published between 1979 and 1990 and one published in 2014. The studies were carried out in hospital settings in China, Denmark, Belgium, and the UK.
Six studies provided six comparisons. Due to the heterogeneity of studies, it was not appropriate to conduct meta-analyses. Four studies evaluated the effectiveness of dextranomer beads/paste; however, each study used a different comparator (Eusol-soaked dressings, 10% aqueous polyvinylpyrrolidone, 0.1% chloramine-soaked packs, and silicone foam elastomer dressing). One study compared streptokinase/streptodornase with saline-soaked dressings, and one compared endoscopic surgical debridement with conventional 'open' surgical debridement.
Five studies reported time to complete debridement (reported as time to a clean wound bed) and three reported time to complete healing. One study reported effect estimates (surgical debridement via endoscopy versus surgical debridement) for time to a clean wound bed and time to complete wound healing, and it was possible to calculate effect estimates for one other study (dextranomer paste versus silicone foam elastomer) for time to complete wound healing. For the other four studies that did not report effect estimates, it was not possible to calculate time to a clean wound bed or time to complete wound healing due to missing variance and participant exclusions.
None of the included studies reported outcomes pertaining to proportion of wounds completely healed, rate of reduction in wound size, rate of infection, or quality of life.
All studies had unclear or high risk of bias for at least one key domain.
Dextranomer paste/beads (autolytic debridement) compared with four different comparators
Four studies compared dextranomer paste or beads with Eusol-soaked gauze (20 participants), 10% aqueous polyvinylpyrrolidone (40 participants), 0.1% chloramine-soaked dressings (28 participants), or silicone foam elastomer (50 participants).
There is very low-certainty evidence that there may be no clear difference in time to a clean wound bed between dextranomer beads and Eusol gauze. The study did not report adverse events.
There is very low-certainty evidence that there may be no difference in time to a clean wound bed between dextranomer paste and 10% aqueous polyvinylpyrrolidone gauze. There was low-certainty evidence that there may be no difference in deaths and serious adverse events.
There may be a difference in time until the wounds were clinically clean and time to complete wound healing between dextranomer paste and 0.1% chloramine favouring 0.1% chloramine, but we are very uncertain. There is low-certainty evidence that there may be no difference in deaths and serious adverse events.
There is very low-certainty evidence that there may be no difference in time to complete healing between dextranomer beads and silicone foam elastomer. The study did not report adverse events.
Streptokinase/streptodornase solution (enzymatic) compared with saline-soaked dressings
One study (21 participants) compared enzymatic debridement with saline-soaked dressings. There is low-certainty evidence that there may be no difference in time to a clean wound bed or secondary suture between streptokinase/streptodornase and saline-soaked dressings. There is very low-certainty evidence that there may be no difference in deaths and serious adverse events.
Surgical debridement via endoscopic ('keyhole') surgery compared with surgical debridement by 'open' surgery (the wound is opened using a scalpel)
One study (106 participants) reported time to complete wound healing and time to a clean wound bed. There is low-certainty evidence that there may be a reduction in time to complete wound healing and very low-certainty evidence that there may be no difference in time to a clean wound bed with surgical debridement via endoscopy compared to 'open' surgical debridement. The study did not report adverse events.
Overall, the evidence was low to very low-certainty for all outcomes.
Five included studies were published before 1991 and investigated treatments that are no longer available. Worldwide production of dextranomer products has been discontinued, except for dextranomer paste, which is currently only available in South Africa. Furthermore, Eusol, used in one study as the comparator to dextranomer, is rarely used due to risk of harmful effects on healthy tissue and the enzymatic agent streptokinase/streptodornase is no longer available worldwide.