Vincent Gabriel

Evidence Based Review for the Treatment of Post-burn Pruritus

Pruritus is one of the most common and distressing complications of burns. It is often debilitating and interferes with sleep, activities of daily living and may cause additional tissue damage from scratching. This systematic review classified and ranked 10 trials and one case report for the effective treatment of post-burn pruritus. A literature search was performed using Ovid Medline from 1950 to present, limited to English and used the search terms pruritus, itching, and burns. The studies available were evaluated using the Physiotherapy Evidence Database scoring system. Each article was then classified according to the Practice Guidelines for Burn Care 2006, a practice guideline published in the Journal of Burn Care and Research. Ten trials were available and all were accepted for analysis. The evidence was classified class II or class III, meeting criteria for guideline status according to the Practice Guidelines of Burn Care 2006. The best quality study for the pharmacological treatment of post-burn pruritus was selective histamine receptor antagonists. The best quality study for the non-pharmacological treatment of post-burn pruritus was the use of pulse dye laser. A paucity of literature exists for the treatment of post-burn pruritus. Also, in the search for effective treatments of post-burn pruritus, there is not a consistent and detailed instrument of measure available for use. Currently, there is no quality evidence available for the treatment of post-burn pruritus and prospective, randomized controlled trials are needed.

Burns as a Result of Assault: Associated Risk Factors, Injury Characteristics, and Outcomes

The purpose of this study was to identify specific premorbid factors and injury characteristics associated with intentional burn injuries and to compare outcomes for individuals injured by assault and those with unintentional injuries. Participants sustaining major burns from May 1994 to August 2005 and consenting to a multisite, prospective, longitudinal outcome study were included. Etiology of the injury was classified as intentional (i.e., assault) or unintentional. Subjects <18 years old or with self-inflicted burns were excluded. Statistical analysis was performed with t-tests, &khgr;2 tests, and analysis of variance. Eighty patients sustained intentional burn injuries and 1982 subjects sustained nonintentional burn injuries. Compared to patients with nonintentional burns, those with burns related to assault were more likely to be female, black, and unemployed and to have higher rates of premorbid substance use. Between the groups, there were no significant differences in preinjury living situation, education level, history of psychiatric treatment, or hospital length of stay. The intentional-burn group had larger burns and a greater in-hospital mortality rate, and these patients were less likely to be discharged to home. They also demonstrated significantly greater levels of psychological distress during the acute hospitalization but not at follow-up. Understanding the unique characteristics and needs of patients with intentional burn injuries is important because these individuals are less likely to have a steady income and more likely to rely on community social services. Affordable and accessible community-based health services are necessary in order to improve their outcomes.

Patient experiences living with split thickness skin grafts.

The standard of care for deep burns is autologous split thickness skin grafting. Although adequate to resurface a deep wound, the resulting skin is chronically abnormal. The purpose of this study was to describe the experience of patients with split thickness skin grafts to help guide future investigations related to skin regeneration. In this study, an interpretive description qualitative methodology was employed. Subjects participated in a two-part single patient interview that was recorded and transcribed. A nurse with experience in clinical burn care coded and interpreted the data. Participants were recruited through presentation to a university based outpatient burn clinic for follow up from autologous split thickness skin grafting. Eight male patients and four female patients 20-62 years old ranging 2-29 months post-skin grafting were enrolled in the study. The most significant concerns voiced by patients were identified and organized into five themes: (1) a new normal, (2) split thickness skin graft symptoms, (3) appearance of new skin, (4) coping, and (5) participation in future clinical trials. Participants reported that the abnormalities related to their split thickness skin grafts were significant enough that they would be willing to participate in a future clinical trial investigating new cell-based therapies.

Assessment of Recovery from Burn Related Neuropathy by Electrodiagnostic Testing

The purpose of this study was to investigate the recovery of burn-related neuropathies by electrodiagnostic testing. Burn patients who presented to an American Burn Association verified burn center were interviewed and examined for clinical evidence of peripheral neuropathies by a physiatrist. Patients whom consented to participate were tested for electrodiagnostic evidence of peripheral neuropathy. Repeated studies were performed to assess for evidence of recovery. A total of 370 patients were screened. Thirty-six (9.73%) patients had clinical evidence of neuropathy. Eighteen male patients with a mean TBSA burn of 42% had nerve conduction studies performed. Etiologies of the injuries included eight flame, eight electrical, and three others. Seventy-three nerve conduction studies were performed and 58 of the tests were abnormal. The most commonly affected nerve was the median sensory (10). For patients with repeated tests, the mean time between tests was 169 days (SD, 140 days). There was a significant difference between the initial and follow-up test (McNemar’s change test P = .009). In subset analysis of motor and sensory abnormalities, there was no significant difference (P = .07). The most common neuropathy identified in this cohort was the median sensory. Overall, there was improvement in the nerve conduction abnormalities examined. This study suggests that the prognosis for recovery after burn-related neuropathy is good.

Collagen structural alterations contribute to stiffening of tissue after split‐thickness skin grafting

The gold standard treatment for full thickness injuries of the skin is autologous split‐thickness skin grafting. This involves harvesting the epidermis and superficial dermis from healthy skin and transplanting it onto the prepared wound bed. The donor site regenerates spontaneously, but the appendages and cellular components from the dermal layer are excluded from the graft. As a result, the new tissue is inferior; the healed graft site is dry/itchy, has decreased elasticity, increased fragility, and altered sensory function. Because this dermal layer is composed of collagen and other extracellular matrix proteins, the aim was to characterize the changes in the dermal collagen after split thickness grafting that could contribute to a deficit in functionality. This will serve as a baseline for future studies designed to improve skin function using pharmacological or cell‐based therapies for skin repair. A xenograft model whereby human split‐thickness grafts were implanted into full‐thickness defects on immunocompromised (athymic Nu/Nu) mice was used. The grafts were harvested 4 and 8 weeks later. The collagen microstructure was assessed with second harmonic generation with dual‐photon microscopy and light polarization analysis. Collagen fiber stiffness and engagement stretch were estimated by fitting the results of biaxial mechanical tensile tests to a histo‐mechanical constitutive model. The stiffness of the collagen fibril–proteoglycan complex increased from 682 ± 226 kPa/sr to 1016 ± 324 kPa/sr between 4 and 8 weeks postgrafting. At the microstructural level there were significant decreases in both thickness of collagen fibers (3.60 ± 0.34 μm vs. 2.10 ± 0.27 μm) and waviness ratio (2.04 ± 0.17 vs. 1.43 ± 0.08) of the collagen fibers postgrafting. The decrease of the macroscopic engagement stretch from 1.19 ± 0.11 to 1.09 ± 0.08 over time postgrafting mirrored the decrease in waviness measured at the microscopic level. This suggested that the integrity of the collagen fibers was compromised and contributed to the functional deficit of the skin postgrafting.

Treating pain on skin graft donor sites: Review and clinical recommendations

ABSTRACT Split-thickness skin grafting is the most common reconstructive procedure in managing burn injuries. Harvesting split-thickness skin creates a new partial thickness wound referred to as the donor site. Pain at the donor site is reported to be one of the most distressing symptoms during the early postoperative period. Here, we (a) identify strategies for managing donor site pain, (b) assess the quality of individual studies, and (c) formulate evidence-based recommendations based on the amount and consistency of evidence. Our analysis revealed five distinct approaches to minimize donor site pain. These include: continuous subcutaneous local anesthetic infusion (three studies), subcutaneous anesthetic injection (five studies), topical agents (six studies), nonpharmacological interventions (three studies), and wound dressings (18 studies). Available randomized control trials typically evaluated pain on standardized scales (i.e. Visual Analog Scale, Numerical Rating Scale), and compared the experimental group with standard care. Recommended treatments include: (a) subcutaneous anesthetic injection of adrenaline-lidocaine; (b) ice application; (c) topical agents, such as lidocaine and bupivacaine; and (d) hydrocolloid- and polyurethane-based wound dressings accompanied with fibrin sealant. Methodologically sound randomized control trials examining the efficacy of modified tumescent solution, ropivacaine, plasma therapy, noncontact ultrasound, and morphine gels are lacking and should be a priority for future research.

Response of human skin to esthetic scarification

This study was undertaken to investigate changes in RNA expression in previously healthy adult human skin following thermal injury induced by contact with hot metal that was undertaken as part of esthetic scarification, a body modification practice. Subjects were recruited to have pre-injury skin and serial wound biopsies performed. 4 mm punch biopsies were taken prior to branding and 1 h, 1 week, and 1, 2 and 3 months after injury. RNA was extracted and quality assured prior to the use of a whole-genome based bead array platform to describe expression changes in the samples using the pre-injury skin as a comparator. Analysis of the array data was performed using k-means clustering and a hypergeometric probability distribution without replacement and corrections for multiple comparisons were done. Confirmatory q-PCR was performed. Using a k of 10, several clusters of genes were shown to co-cluster together based on Gene Ontology classification with probabilities unlikely to occur by chance alone. OF particular interest were clusters relating to cell cycle, proteinaceous extracellular matrix and keratinization. Given the consistent expression changes at 1 week following injury in the cell cycle cluster, there is an opportunity to intervene early following burn injury to influence scar development.

Measurement of change in the mechanical properties of burned skin to therapist intervention with a vacuum device

INTRODUCTION The currently available clinical scales used to describe healed burn wounds have limitations. Quantitative measurement of the outcomes from burn therapy treatment would be useful in planning clinical care, resource allocation and research. The purpose of this study was to observe the measurements of a portable materials testing device before and after burn therapist intervention for closed burns. METHODS A recording was taken using a hand-held vacuum device to measure deformation of the skin in the same location prior to and following a treatment session with a burn therapist in an outpatient clinic at a tertiary burn center. RESULTS Twenty-eight subjects were recruited to the study. Statistically significant differences were noted in modulus and elasticity change between sheet and meshed split thickness autografts (p=0.0233). Positive change in modulus was correlated with increasing therapy time (R=0.46), specifically for meshed grafts (R=0.70). Positive change in modulus was noted in therapy time greater than 48 min. CONCLUSIONS Quantitative measurement of the outcomes of burn therapies on the mechanical properties of healed burns is possible in an outpatient clinic setting. Improvement in the stiffness of burn scars was observed in treatment sessions that last at least 48 min.

Burns from illegal cannabis oil manufacturing: a case series

BACKGROUND The increasing consideration of cannabis legalization in Canada and the United States has motivated physicians to assess its prospective impact on the health care system. Health care providers in the burns community are concerned about injuries sustained as a result of the illegal manufacturing of cannabis oil because it involves highly flammable reagents. METHODS We report a retrospective case series of patients with cannabis oil burns (identified by evidence of combustion during cannabis oil manufacturing) treated from April 2012 to March 2014 at the Foothills Medical Centre in Calgary, Alberta, Canada. We compare the characteristics of these patients with those of patients admitted over the same period with any burns. RESULTS We found that 12 (out of 161 patients) admitted over the review period sustained burns from cannabis oil manufacturing. Compared with patients in the total burn group, patients with cannabis oil burns were younger (75% and 48% were younger than 41 years in the group with cannabis oil burns and the total burn group, respectively), were more likely to be male (83% in the group with cannabis oil burns v. 74% in the total burn group) and sustained burns over a larger percentage of their total body surface area (24% v. 9%). Patients with cannabis oil burns also required extensive surgical management (skin grafting in 75% of cases) and spent a substantial amount of time (mean 32 d) in the burn unit. INTERPRETATION Burns from illegal cannabis oil manufacturing are large, require extensive management and involve younger patients than burns in general. Given that the frequency of cannabis oil burns may increase in Canada after legalization, Canadian burn centres are encouraged to monitor and report on cases with this injury mechanism.

Firefighter willingness to participate in a stem cell clinical trial for burns: A mixed methods study

Adult stem cells represent a potentially renewable and autologous source of cells to regenerate skin and improve wound healing. Firefighters are at risk of sustaining a burn and potentially benefiting from a split thickness skin graft (STSG). This mixed methods study examined firefighter willingness to participate in a future stem cell clinical trial, outcome priorities and factors associated with this decision. METHODS A sequential explanatory mixed methods design was used. The quantitative phase (online questionnaire) was followed by the qualitative phase (semi-structured interviews). A sample of 149 firefighters completed the online survey, and a purposeful sample of 15 firefighters was interviewed. RESULTS A majority (74%) reported they would participate in a future stem cell clinical trial if they experienced burn benefiting from STSG. Hypothetical concerns related to receiving a STSG were pain, itch, scarring/redness and skin durability. Participants indicated willingness to undergo stem cell therapy if the risk of no improvement was 43% or less. Risk tolerance was predicted by perceived social support and having children. Interviews revealed four main themes: a desire to help others, improving clinical outcomes, trusting relationships, and a belief in scientific investigation. Many participants admitted lacking sufficient knowledge to make an informed decision regarding stem cell therapies. CONCLUSIONS Firefighters indicated they were largely willing to participate in a stem cell clinical trial but also indicated a lack of knowledge upon which to make a decision. Public education of the role of stem cells in STSG will be increasingly important as clinical trials are developed.