Protocol for a systematic review of quantitative burn wound microbiology in the management of burns patients

BACKGROUND: Sepsis from burn injuries can result from colonisation of burn wounds, especially in large surface area burns. Reducing bacterial infection will reduce morbidity and mortality, and mortality for severe burns can be as high as 15 %. There are various quantitative and semi-quantitative techniques to monitor bacterial load on wounds. In the UK, burn wounds are typically monitored for the presence or absence of bacteria through the collection and culture of swabs, but no absolute count is obtained. Quantitative burn wound culture provides a measure of bacterial count and is gaining increased popularity in some countries. It is however more resource intensive, and evidence for its utility appears to be inconsistent. This systematic review therefore aims to assess the evidence on the utility and reliability of different quantitative microbiology techniques in terms of diagnosing or predicting clinical outcomes. METHODS/DESIGN: Standard systematic review methods aimed at minimising bias will be employed for study identification, selection and data extraction. Bibliographic databases and ongoing trial registers will be searched and conference abstracts screened. Studies will be eligible if they are prospective studies or systematic reviews of burn patients (any age) for whom quantitative microbiology has been performed, whether it is compared to another method. Quality assessment will be based on quality assessment tools for diagnostic and prognostic studies and tailored to the review as necessary. Synthesis is likely to be primarily narrative, but meta-analysis may be considered where clinical and methodological homogeneity exists. DISCUSSION: Given the increasing use of quantitative methods, this is a timely systematic review, which will attempt to clarify the evidence base. As far as the authors are aware, it will be the first to address this topic. TRIAL REGISTRATION: PROSPERO, CRD4201502390

The antibacterial activity of acetic acid against biofilm-producing pathogens of relevance to burns patients

Introduction: Localised infections, and burn wound sepsis are key concerns in the treatment of burns patients, and prevention of colonisation largely relies on biocides. Acetic acid has been shown to have good antibacterial activity against various planktonic organisms, however data is limited on efficacy, and few studies have been performed on biofilms. Objectives: We sought to investigate the antibacterial activity of acetic acid against important burn wound colonising organisms growing planktonically and as biofilms. Methods: Laboratory experiments were performed to test the ability of acetic acid to inhibit growth of pathogens, inhibit the formation of biofilms, and eradicate pre-formed biofilms. Results: Twenty-nine isolates of common wound-infecting pathogens were tested. Acetic acid was antibacterial against planktonic growth, with an minimum inhibitory concentration of 0.16-0.31% for all isolates, and was also able to prevent formation of biofilms (at 0.31 %). Eradication of mature biofilms was observed for all isolates after three hours of exposure. Conclusions: This study provides evidence that acetic acid can inhibit growth of key burn wound pathogens when used at very dilute concentrations. Owing to current concerns of the reducing efficacy of systemic antibiotics, this novel biocide application offers great promise as a cheap and effective measure to treat infections in burns patients

Acetic acid dressings converted skin graft donor sites into full thickness wounds in a burned infant, a case report

Colonisation with Pseudomonas aeruginosa considerably increases the mortality rate in burns, due to its common resistance to antibiotic treatment. Simple dressings consisting of gauze soaked in acetic acid have been proven as effective in eradicating pseudomonas however few studies have demonstrated the optimum concentration or treatment regime.We report a burned infant who developed iatrogenic chemical injuries to her donor sites as a complication of topical acetic acid treatment. Possible contributing factors and strategies to improve safety are discussed

Seeking the source of Pseudomonas aeruginosa infections in a recently opened hospital : an observational study using whole-genome sequencing

Objectives: Pseudomonas aeruginosa is a common nosocomial pathogen responsible for significant morbidity and mortality internationally. Patients may become colonised or infected with P. aeruginosa after exposure to contaminated sources within the hospital environment. The aim of this study was to determine whether whole-genome sequencing (WGS) can be used to determine the source in a cohort of burns patients at high risk of P. aeruginosa acquisition. Study design: An observational prospective cohort study. Setting: Burns care ward and critical care ward in the UK. Participants: Patients with >7% total burns by surface area were recruited into the study. Methods: All patients were screened for P. aeruginosa on admission and samples taken from their immediate environment, including water. Screening patients who subsequently developed a positive P. aeruginosa microbiology result were subject to enhanced environmental surveillance. All isolates of P. aeruginosa were genome sequenced. Sequence analysis looked at similarity and relatedness between isolates. Results: WGS for 141 P. aeruginosa isolates were obtained from patients, hospital water and the ward environment. Phylogenetic analysis revealed eight distinct clades, with a single clade representing the majority of environmental isolates in the burns unit. Isolates from three patients had identical genotypes compared with water isolates from the same room. There was clear clustering of water isolates by room and outlet, allowing the source of acquisitions to be unambiguously identified. Whole-genome shotgun sequencing of biofilm DNA extracted from a thermostatic mixer valve revealed this was the source of a P. aeruginosa subpopulation previously detected in water. In the remaining two cases there was no clear link to the hospital environment. Conclusions: This study reveals that WGS can be used for source tracking of P. aeruginosa in a hospital setting, and that acquisitions can be traced to a specific source within a hospital ward

A systematic review of quantitative burn wound microbiology in the management of burns patients.

BACKGROUND The early diagnosis of infection or sepsis in burns are important for patient care. Globally, a large number of burn centres advocate quantitative cultures of wound biopsies for patient management, since there is assumed to be a direct link between the bioburden of a burn wound and the risk of microbial invasion. Given the conflicting study findings in this area, a systematic review was warranted. METHODS Bibliographic databases were searched with no language restrictions to August 2015. Study selection, data extraction and risk of bias assessment were performed in duplicate using pre-defined criteria. Substantial heterogeneity precluded quantitative synthesis, and findings were described narratively, sub-grouped by clinical question. RESULTS Twenty six laboratory and/or clinical studies were included. Substantial heterogeneity hampered comparisons across studies and interpretation of findings. Limited evidence suggests that (i) more than one quantitative microbiology sample is required to obtain reliable estimates of bacterial load; (ii) biopsies are more sensitive than swabs in diagnosing or predicting sepsis; (iii) high bacterial loads may predict worse clinical outcomes, and (iv) both quantitative and semi-quantitative culture reports need to be interpreted with caution and in the context of other clinical risk factors. CONCLUSION The evidence base for the utility and reliability of quantitative microbiology for diagnosing or predicting clinical outcomes in burns patients is limited and often poorly reported. Consequently future research is warranted

Hydrotherapy in burn care : a survey of hydrotherapy practices in the UK and Ireland and literature review

Introduction Hydrotherapy is widely used in burns management however there are risks associated with its use, in particular cross-infection. Data regarding indications and techniques in common use is deficient. This study aimed to investigate hydrotherapy practices in the UK and Ireland. Methods A survey of the hydrotherapy practice of major burn care providers was performed by e mail and where necessary, follow up telephone contact. Results The survey included 28 burn care providers. 27 reported using hydrotherapy. Only 11 (41%) had defined indication criteria with 4 (15%) implementing a specific protocol. Variations in hydrotherapy practice were seen. Conclusion Hydrotherapy is used nationwide, however considerable variation in practice exists. One area worthy of further consideration is the need for appropriate standards of infection control

Pressure-garment therapy for preventing hypertrophic scarring after burn injury

Background: Burn damage to skin often results in scarring; however in some individuals the failure of normal wound‐healing processes results in excessive scar tissue formation, termed 'hypertrophic scarring'. The most commonly used method for the prevention and treatment of hypertrophic scarring is pressure‐garment therapy (PGT). PGT is considered standard care globally; however, there is continued uncertainty around its effectiveness.Objectives: To evaluate the benefits and harms of pressure‐garment therapy for the prevention of hypertrophic scarring after burn injury.Search methods: We used standard, extensive Cochrane search methods. We searched CENTRAL, MEDLINE, Embase, two other databases, and two trials registers on 8 June 2023 with reference checking, citation searching, and contact with study authors to identify additional studies.Selection criteria: We included randomised controlled trials (RCTs) comparing PGT (alone or in combination with other scar‐management therapies) with scar management therapies not including PGT, or comparing different PGT pressures or different types of PGT.Data collection and analysis: At least two review authors independently selected trials for inclusion using predetermined inclusion criteria, extracted data, and assessed risk of bias using the Cochrane RoB 1 tool. We assessed the certainty of evidence using GRADE.Main results: We included 15 studies in this review (1179 participants), 14 of which (1057 participants) presented useable data. The sample size of included studies ranged from 17 to 159 participants. Most studies included both adults and children. Eight studies compared a pressure garment (with or without another scar management therapy) with scar management therapy alone, five studies compared the same pressure garment at a higher pressure versus a lower pressure, and two studies compared two different types of pressure garments. Studies used a variety of pressure garments (e.g. in‐house manufactured or a commercial brand). Types of scar management therapies included were lanolin massage, topical silicone gel, silicone sheet/dressing, and heparin sodium ointment.Meta‐analysis was not possible as there was significant clinical and methodological heterogeneity between studies. Main outcome measures were scar improvement assessed using the Vancouver Scar Scale (VSS) or the Patient and Observer Scar Assessment Scale (POSAS) (or both), pain, pruritus, quality of life, adverse events, and adherence to therapy. Studies additionally reported a further 14 outcomes, mostly individual scar parameters, some of which contributed to global scores on the VSS or POSAS. The amount of evidence for each individual outcome was limited. Most studies had a short follow‐up, which may have affected results as the full effect of any therapy on scar healing may not be seen until around 18 months.PGT versus no treatment/lanolinWe included five studies (378 participants). The evidence is very uncertain on whether PGT improves scars as assessed by the VSS compared with no treatment/lanolin. The evidence is also very uncertain for pain, pruritus, adverse events, and adherence. No study used the POSAS or assessed quality of life. One additional study (122 participants) did not report useable data.PGT versus siliconeWe included three studies (359 participants). The evidence is very uncertain on the effect of PGT compared with silicone, as assessed by the VSS and POSAS. The evidence is also very uncertain for pain, pruritus, quality of life, adverse events, adherence, and other scar parameters. It is possible that silicone may result in fewer adverse events or better adherence compared with PGT but this was also based on very low‐certainty evidence.PGT plus silicone versus no treatment/lanolinWe included two studies (200 participants). The evidence is very uncertain on whether PGT plus silicone improves scars as assessed by the VSS compared with no treatment/lanolin. The evidence is also very uncertain for pain, pruritus, and adverse events. No study used the POSAS or assessed quality of life or adherence.PGT plus silicone versus siliconeWe included three studies (359 participants). The evidence is very uncertain on the effect of PGT plus silicone compared with silicone, as assessed by the VSS and POSAS. The evidence is also very uncertain for pain, pruritus, quality of life, adverse events, and adherence.PGT plus scar management therapy including silicone versus scar management therapy including siliconeWe included one study (88 participants). The evidence is very uncertain on the effect of PGT plus scar management therapy including silicone versus scar management therapy including silicone, as assessed by the VSS and POSAS. The evidence is also very uncertain for pain, pruritus, quality of life, adverse events, and adherence.High‐pressure versus low‐pressure garmentsWe included five studies (262 participants). The evidence is very uncertain on the effect of high pressure versus low pressure PGT on adverse events and adherence. No study used the VSS or the POSAS or assessed pain, pruritus, or quality of life.Different types of PGT (Caroskin Tricot + an adhesive silicone gel sheet versus Gecko Nanoplast (silicone gel bandage))We included one study (60 participants). The evidence is very uncertain on the effect of Caroskin Tricot versus Gecko Nanoplast on the POSAS, pain, pruritus, and adverse events. The study did not use the VSS or assess quality of life or adherence.Different types of pressure garments (Jobst versus Tubigrip)We included one study (110 participants). The evidence is very uncertain on the adherence to either Jobst or Tubigrip. This study did not report any other outcomes.Authors' conclusions: There is insufficient evidence to recommend using either PGT or an alternative for preventing hypertrophic scarring after burn injury. PGT is already commonly used in practice and it is possible that continuing to do so may provide some benefit to some people. However, until more evidence becomes available, it may be appropriate to allow patient preference to guide therapy