Review question
We reviewed the evidence about the effects of topical (applied to the surface of the skin) treatments for healing burn wounds on the face or neck. We wanted to find out which treatments were most effective at healing these wounds and improving the appearance of scars, which is a particularly important issue in relation to facial burn injuries. We also wanted to find out how topical treatments affected the risk of complications such as infection and pain, and how they impacted on peoples' quality of life.
Background
Burn injuries are an important health problem, and a major global cause of disability and disfigurement in both adults and children. Women and children in low-income countries are at particular risk. Burns pose particular problems when they occur on the head or neck. The face is central to a person's identity and plays a vital role in communication. Other basic functions such as hearing, smell and breathing may become affected as a direct result of a facial burn. Topical treatments such as (non) antimicrobial creams and skin substitutes, are most commonly used to treat facial burns. We wanted to compare the effectiveness of these treatments to evaluate their benefits and harms.
Study characteristics
In December 2019, we searched for randomised controlled trials (RCTs) investigating topical treatments for facial burns. RCTs are medical studies where the treatment or care people receive is chosen at random. This type of study design provides the most reliable health evidence about whether different approaches to treatment or care can make a difference. We found 12 studies that were suitable for inclusion in this review update, with 507 participants with mean ages ranging from 5.3 to 41.9 years. Three studies compared antimicrobials with non-antimicrobials agents, two studies compared different antimicrobials, four studies compared skin substitutes with antimicrobials, while four studies compared a variety of topical treatments. One study contributed to two comparisons. Eight studies were small (fewer than 40 participants) and almost all studies were at high risk of bias due to lack of blinding (where participants and evaluators may have known which group the participants were allocated to and interpreted effects differently).
Key results
Overall, there is mainly low to very low-certainty evidence on the effects of any topical intervention on wound healing or infection in people with facial burns. In addition, there is low to very low-certainty evidence on the effects of the included interventions on need for surgery, pain, scar quality, patient satisfaction, length of hospital stay and side effects.
All results were at high risk of bias and varied, which may have exaggerated the effects.
Certainty of the evidence
Overall, the certainty of the evidence about the effectiveness of topical treatments for facial burns is low to very low. There is insufficient reliable evidence as to whether topical treatments improve outcomes for people with facial burns including improving wound healing, or rates of infection. Better trial design and reporting of these studies is required to contribute to evidence-based burn care.
How up to date is this review?
We searched for studies that had been published up to December 2019.
There is mainly low to very low-certainty evidence on the effects of any topical intervention on wound healing in people with facial burns. The number of RCTs in burn care is growing, but the body of evidence is still hampered due to an insufficient number of studies that follow appropriate evidence-based standards of conducting and reporting RCTs.
Burn injuries are an important health problem. They occur frequently in the head and neck region. The face is the area central to a person's identity that provides our most expressive means of communication. Topical interventions are currently the cornerstone of treatment of burns to the face.
To assess the effects of topical interventions on wound healing in people with facial burns of any depth.
In December 2019 we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting.
Randomised controlled trials (RCTs) that evaluated the effects of topical treatment for facial burns were eligible for inclusion in this review.
Two review authors independently performed study selection, data extraction, risk of bias assessment and GRADE assessment of the certainty of the evidence.
In this first update, we included 12 RCTs, comprising 507 participants.
Most trials included adults admitted to specialised burn centres after recent burn injuries.
Topical agents included antimicrobial agents (silver sulphadiazine (SSD), Aquacel-Ag, cerium-sulphadiazine, gentamicin cream, mafenide acetate cream, bacitracin), non-antimicrobial agents (Moist Exposed Burn Ointment (MEBO), saline-soaked dressings, skin substitutes (including bioengineered skin substitute (TransCyte), allograft, and xenograft (porcine Xenoderm), and miscellaneous treatments (growth hormone therapy, recombinant human granulocyte-macrophage colony-stimulating factor hydrogel (rhGMCS)), enzymatic debridement, and cream with Helix Aspersa extract).
Almost all the evidence included in this review was assessed as low or very low-certainty, often because of high risk of bias due to unclear randomisation procedures (i.e. sequence generation and allocation concealment); lack of blinding of participants, providers and sometimes outcome assessors; and imprecision resulting from few participants, low event rates or both, often in single studies.
Topical antimicrobial agents versus topical non-antimicrobial agents
There is moderate-certainty evidence that there is probably little or no difference between antimicrobial agents and non-antimicrobial agents (SSD and MEBO) in time to complete wound healing (hazard ratio (HR) 0.84 (95% confidence interval (CI) 0.78 to 1.85, 1 study, 39 participants). Topical antimicrobial agents may make little or no difference to the proportion of wounds completely healed compared with topical non-antimicrobial agents (comparison SSD and MEBO, risk ratio (RR) 0.94, 95% CI 0.68 to 1.29; 1 study, 39 participants; low-certainty evidence). We are uncertain whether there is a difference in wound infection (comparison topical antimicrobial agent (Aquacel-Ag) and MEBO; RR 0.38, 95% CI 0.12 to 1.21; 1 study, 40 participants; very low-certainty evidence). No trials reported change in wound surface area over time or partial wound healing. There is low-certainty evidence for the secondary outcomes scar quality and patient satisfaction. Two studies assessed pain but it was incompletely reported.
Topical antimicrobial agents versus other topical antimicrobial agents
It is uncertain whether topical antimicrobial agents make any difference in effects as the evidence is low to very low-certainty. For primary outcomes, there is low-certainty evidence for time to partial (i.e. greater than 90%) wound healing (comparison SSD versus cerium SSD: mean difference (MD) –7.10 days, 95% CI –16.43 to 2.23; 1 study, 142 participants). There is very low-certainty evidence regarding whether topical antimicrobial agents make a difference to wound infection (RR 0.73, 95% CI 0.46 to 1.17; 1 study, 15 participants). There is low to very low-certainty evidence for the proportion of facial burns requiring surgery, pain, scar quality, adverse effects and length of hospital stay.
Skin substitutes versus topical antimicrobial agents
There is low-certainty evidence that a skin substitute may slightly reduce time to partial (i.e. greater than 90%) wound healing, compared with a non-specified antibacterial agent (MD –6.00 days, 95% CI –8.69 to –3.31; 1 study, 34 participants).
We are uncertain whether skin substitutes in general make any other difference in effects as the evidence is very low certainty. Outcomes included wound infection, pain, scar quality, adverse effects of treatment and length of hospital stay.
Single studies showed contrasting low-certainty evidence. A bioengineered skin substitute may slightly reduce procedural pain (MD –4.00, 95% CI –5.05 to –2.95; 34 participants) and background pain (MD –2.00, 95% CI –3.05 to –0.95; 34 participants) compared with an unspecified antimicrobial agent. In contrast, a biological dressing (porcine Xenoderm) might slightly increase pain in superficial burns (MD 1.20, 95% CI 0.65 to 1.75; 15 participants (30 wounds)) as well as deep partial thickness burns (MD 3.00, 95% CI 2.34 to 3.66; 10 participants (20 wounds)), compared with antimicrobial agents (Physiotulle Ag (Coloplast)).
Miscellaneous treatments versus miscellaneous treatments
Single studies show low to very low-certainty effects of interventions. Low-certainty evidence shows that MEBO may slightly reduce time to complete wound healing compared with saline soaked dressing (MD –1.7 days, 95% CI –3.32 to –0.08; 40 participants). In addition, a cream containing Helix Aspersa may slightly increase the proportion of wounds completely healed at 14 days compared with MEBO (RR 4.77, 95% CI 1.87 to 12.15; 43 participants). We are uncertain whether any miscellaneous treatment in the included studies makes a difference in effects for the outcomes wound infection, scar quality, pain and patient satisfaction as the evidence is low to very low-certainty.