Review question
We reviewed the evidence about whether antiseptics are safe and effective for treating burn wounds.
Background
Burn wounds cause many injuries and deaths worldwide. People with burn wounds are especially vulnerable to infections. Antiseptics prevent the growth of micro-organisms such as bacteria. They can be applied to burn wounds in dressings or washes, which may help to prevent infection and encourage wound healing. We wanted to find out if antiseptics are more effective than other types of treatment, or whether one antiseptic may be more effective than others, in reducing infection and speeding up healing.
Study characteristics
In September 2016 we searched for randomised controlled trials (RCTs) involving antiseptic treatments for burn wounds. We included 56 studies with 5807 participants. Most participants were adults with recent second-degree burns taking up less than 40% of their total body surface area. The antiseptics used included: silver-based, honey, iodine-based, chlorhexidine or polyhexanide (biguanides). Most studies compared antiseptics with a topical antibiotic (applied to the skin). A smaller number of studies compared antiseptics with a non-antibacterial treatment, or with another antiseptic.
Key results
The majority of studies compared antiseptic treatments with silver sulfadiazine (SSD), a topical antibiotic used commonly in the treatment of burns. There is low certainty evidence that some antiseptics may speed up average times to healing compared with SSD. There is also moderate certainty evidence that burns treated with honey probably heal more quickly compared with those treated with topical antibiotics. Most other comparisons did not show a clear difference between antiseptics and antibiotics.
There is evidence that burns treated with honey heal more quickly (high certainty evidence) and are more likely to heal (moderate certainty evidence) compared with those given a range of non-antibacterial treatments, some of which were unconventional. Burns treated with antiseptics such as nanocrystalline silver or merbromin may heal more quickly on average than those treated with Vaseline gauze or other non-antibacterial treatments (moderate or low certainty evidence). Comparisons of two different antiseptics were limited but average time to healing may be slightly quicker for wounds treated with povidone iodine compared with chlorhexidine (low certainty evidence). Few participants in the studies experienced serious side effects, but this was not always reported. The results do not allow us to be certain about differences in infection rates. Mortality was low where reported.
Quality of the evidence
Most studies were not well reported and this makes it difficult to be sure if they were at risk of bias. In many cases a single (often small) study provides all the evidence for the comparative effects of the different treatments; and some similar studies provided conflicting results. Where there is moderate or high certainty evidence clinicians will need to consider whether the evidence from the comparison is relevant to their patients.
This plain language summary is up to date as of September 2016.
It was often uncertain whether antiseptics were associated with any difference in healing, infections, or other outcomes. Where there is moderate or high certainty evidence, decision makers need to consider the applicability of the evidence from the comparison to their patients. Reporting was poor, to the extent that we are not confident that most trials are free from risk of bias.
Burn wounds cause high levels of morbidity and mortality worldwide. People with burns are particularly vulnerable to infections; over 75% of all burn deaths (after initial resuscitation) result from infection. Antiseptics are topical agents that act to prevent growth of micro-organisms. A wide range are used with the intention of preventing infection and promoting healing of burn wounds.
To assess the effects and safety of antiseptics for the treatment of burns in any care setting.
In September 2016 we searched the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid MEDLINE (In-Process & Other Non-Indexed Citations), Ovid Embase, and EBSCO CINAHL. We also searched three clinical trials registries and references of included studies and relevant systematic reviews. There were no restrictions based on language, date of publication or study setting.
We included randomised controlled trials (RCTs) that enrolled people with any burn wound and assessed the use of a topical treatment with antiseptic properties.
Two review authors independently performed study selection, risk of bias assessment and data extraction.
We included 56 RCTs with 5807 randomised participants. Almost all trials had poorly reported methodology, meaning that it is unclear whether they were at high risk of bias. In many cases the primary review outcomes, wound healing and infection, were not reported, or were reported incompletely.
Most trials enrolled people with recent burns, described as second-degree and less than 40% of total body surface area; most participants were adults. Antiseptic agents assessed were: silver-based, honey, Aloe Vera, iodine-based, chlorhexidine or polyhexanide (biguanides), sodium hypochlorite, merbromin, ethacridine lactate, cerium nitrate and Arnebia euchroma. Most studies compared antiseptic with a topical antibiotic, primarily silver sulfadiazine (SSD); others compared antiseptic with a non-antibacterial treatment or another antiseptic. Most evidence was assessed as low or very low certainty, often because of imprecision resulting from few participants, low event rates, or both, often in single studies.
Antiseptics versus topical antibiotics
Compared with the topical antibiotic, SSD, there is low certainty evidence that, on average, there is no clear difference in the hazard of healing (chance of healing over time), between silver-based antiseptics and SSD (HR 1.25, 95% CI 0.94 to 1.67; I2 = 0%; 3 studies; 259 participants); silver-based antiseptics may, on average, increase the number of healing events over 21 or 28 days' follow-up (RR 1.17 95% CI 1.00 to 1.37; I2 = 45%; 5 studies; 408 participants) and may, on average, reduce mean time to healing (difference in means -3.33 days; 95% CI -4.96 to -1.70; I2 = 87%; 10 studies; 979 participants).
There is moderate certainty evidence that, on average, burns treated with honey are probably more likely to heal over time compared with topical antibiotics (HR 2.45, 95% CI 1.71 to 3.52; I2 = 66%; 5 studies; 140 participants).
There is low certainty evidence from single trials that sodium hypochlorite may, on average, slightly reduce mean time to healing compared with SSD (difference in means -2.10 days, 95% CI -3.87 to -0.33, 10 participants (20 burns)) as may merbromin compared with zinc sulfadiazine (difference in means -3.48 days, 95% CI -6.85 to -0.11, 50 relevant participants). Other comparisons with low or very low certainty evidence did not find clear differences between groups.
Most comparisons did not report data on infection. Based on the available data we cannot be certain if antiseptic treatments increase or reduce the risk of infection compared with topical antibiotics (very low certainty evidence).
Antiseptics versus alternative antiseptics
There may be some reduction in mean time to healing for wounds treated with povidone iodine compared with chlorhexidine (MD -2.21 days, 95% CI 0.34 to 4.08). Other evidence showed no clear differences and is of low or very low certainty.
Antiseptics versus non-antibacterial comparators
We found high certainty evidence that treating burns with honey, on average, reduced mean times to healing in comparison with non-antibacterial treatments (difference in means -5.3 days, 95% CI -6.30 to -4.34; I2 = 71%; 4 studies; 1156 participants) but this comparison included some unconventional treatments such as amniotic membrane and potato peel. There is moderate certainty evidence that honey probably also increases the likelihood of wounds healing over time compared to unconventional anti-bacterial treatments (HR 2.86, 95% C 1.60 to 5.11; I2 = 50%; 2 studies; 154 participants).
There is moderate certainty evidence that, on average, burns treated with nanocrystalline silver dressings probably have a slightly shorter mean time to healing than those treated with Vaseline gauze (difference in means -3.49 days, 95% CI -4.46 to -2.52; I2 = 0%; 2 studies, 204 participants), but low certainty evidence that there may be little or no difference in numbers of healing events at 14 days between burns treated with silver xenograft or paraffin gauze (RR 1.13, 95% CI 0.59 to 2.16 1 study; 32 participants). Other comparisons represented low or very low certainty evidence.
It is uncertain whether infection rates in burns treated with either silver-based antiseptics or honey differ compared with non-antimicrobial treatments (very low certainty evidence). There is probably no difference in infection rates between an iodine-based treatment compared with moist exposed burn ointment (moderate certainty evidence). It is also uncertain whether infection rates differ for SSD plus cerium nitrate, compared with SSD alone (low certainty evidence).
Mortality was low where reported. Most comparisons provided low certainty evidence that there may be little or no difference between many treatments. There may be fewer deaths in groups treated with cerium nitrate plus SSD compared with SSD alone (RR 0.22, 95% CI 0.05 to 0.99; I2 = 0%, 2 studies, 214 participants) (low certainty evidence).