Analysis of the predictors of hypertrophic scarring pain and neuropathic pain after burn

Clinical Symptoms of Postburn Hypertrophic Scars and Analysis of Risk Factors for Itching and Pain Requiring Pharmacological Intervention

BACKGROUND

Pruritus and pain symptoms secondary to hypertrophic scars (HTSs) are associated with multiple factors, with age, body mass index (BMI), and scar thickness being the main risk factors (RFs).

OBJECTIVE

This study mainly discusses the clinical symptoms associated with postburn HTSs and analyzes RFs for itching and pain requiring pharmacological intervention.

MATERIALS AND METHODS

All clinical data of 93 patients with postburn HTSs who visited the Burn Department of Shanghai Seventh People's Hospital between January 1, 2021 and January 1, 2023 were collected and analyzed retrospectively. Referring to the University of North Carolina "4P" Scar Scale, patients were rated as either "with" or "without" according to whether they had "scar itching symptoms requiring pharmacological intervention."

RESULTS

Smoking, third-degree burns, unused silicone drugs, and total burn surface area 30% to 50% were independent RFs for requiring pharmacological intervention for postburn scar pruritus (odds ratio [OR] = 2.998, 3.924, 3.588, and 5.965, p < .05). Age, increased BMI, greater scar thickness, and duration of hyperplasia not more than 1 year significantly increased the risk of scar pain requiring medical intervention (OR = 1.626, 2.441, 20.830, 11.646, and 11.136, p < .05).

CONCLUSION

The clinical value of these factors is that they can help physicians better identify those patients who may require pharmacological intervention to control itching and pain.

Trends and hotspots in burns-related pain research: A bibliometric analysis

OBJECTIVE

The aim of this investigation was to conduct a thorough synthesis of the extant scholarly discourse and to delineate the prevailing global trends in the domain of burn pain, employing a bibliometric analysis.

METHODS

A bibliometric analysis was performed utilizing the Web of Science Core Collection database. Articles were selected based on titles or abstracts containing keywords associated with burns and pain. Both quantitative and qualitative methodologies were applied to examine the retrieved data, encompassing an analysis of publication trends, research themes, and collaboration networks.

RESULTS

The number of articles on this topic has been increasing, averaging an annual growth rate of 6.9 % from 1997 to 2023. Contributions have come from 645 institutions across 53 countries, resulting in 446 papers that span areas such as nursing, anesthesia, and immunology. Key journals include Burns, Journal of Burn Care & Research, and Pain. The United States has demonstrated a significant research output in this field, with active international collaboration, notably with Washington University leading in contributions. Patterson DR was the most prolific author in terms of published papers, while Choiniere M was the most frequently co-cited author. The focus of research has shifted from symptom management to exploring pain mechanisms. Current research priorities in burn pain include "quality of life," "music therapy," and "psychological state." Recent analysis has highlighted key areas in neuropathic pain mechanisms, novel analgesic therapies, and specific groups such as pediatric burn patients. Influential studies have advanced our understanding of pathophysiology, while psychological interventions and inflammation are increasingly receiving attention. Emerging topics include non-pharmacological interventions, psychological support, technology in pain assessment and management, quality of life, and personalized pain management.

CONCLUSION

Research on burn pain is advancing rapidly; however, collaboration among countries and institutions remains limited. Increased cooperation and communication across these entities could significantly advance the field in the future. Future research should prioritize placebo-controlled trials of targeted therapeutic drugs and innovative pain management approaches, with a strong emphasis on patient outcomes and quality of life.

Long non-coding RNA CRNDE promotes the progress of hypertrophic scar via regulating the proliferation and migration of hypertrophic scar fibroblasts through targeting microRNA-29a-3p

Hypertrophic scar (HS) represents an excessive fibrotic response during the healing of skin injuries, constituting a common and intricate pathological process that is tightly regulated. This study aimed to explore the clinical significance and potential mechanisms of long non-coding RNA CRNDE in the development of HS. This study encompassed 71 HS patients, and the expression levels of lncRNA CRNDE were assessed via RT-qPCR. Concurrently, the concentrations of collagen I A1 and collagen III A1 were quantified using the Enzyme-linked immunosorbent assay (ELISA) technique, while the cellular activities of hypertrophic scar fibroblasts (HSFs) were evaluated through CCK-8 assays, Transwell migration assays, and flow cytometry. Furthermore, a dual-luciferase reporter gene assay was conducted to confirm the target interaction between CRNDE and microRNA -29a-3p. LncRNA CRNDE was markedly upregulated in HS tissues. Silencing lncRNA CRNDE led to a reduction in collagen I A1 and collagen III A1 levels in HSFs, inhibited cell proliferation and migration, and simultaneously promoted cell apoptosis. Moreover, miR-29a-3p expression was downregulated in HS tissues and exhibited a negative correlation with lncRNA CRNDE expression. The effects of lncRNA CRNDE knockdown on collagen I A1/ III A1 levels, cell proliferation, migration, and apoptosis could be partially mitigated by a miR-29a-3p inhibitor. LncRNA CRNDE influenced the biological behaviors of HS through its interaction with miR-29a-3p.

Evaluating the effectiveness and safety of pulsed dye laser alone, the combination of pulsed dye laser and botulinum toxin type A, and the combination of pulsed dye laser and triamcinolone injection in the treatment of hypertrophic and keloid scars: a three-arm randomized controlled clinical trial

To evaluate the efficacy and safety of pulsed dye laser (PDL) alone, the combination of PDL and botulinum toxin type A (BTA) injection, and the combination of PDL and triamcinolone injection in the treatment of hypertrophic scars and keloids. In this three-arm, single-blind randomized controlled clinical trial, 10 patients over 18 years old with hypertrophic scars or keloids were enrolled. Each patient had at least 3 lesions, each measuring at least 10 × 10 square centimeters or 10 centimeters long. In the first treatment session, each of the 3 lesions was randomly assigned to one of three interventions: PDL (control), PDL with BTA injection (at a concentration of 2 units/cm2), or PDL with triamcinolone injection (20 mg/cc). All the interventions carried out in the groups have been repeated in three sessions. One follow-up visit took place one month after the last session, without any intervention. Clinical images of the lesions were collected during the treatment sessions. A blinded dermatologist assessed the effectiveness of the treatment using a physician global assessment score and the Vancouver Scar Scale (VSS). Patient satisfaction and any side effects were recorded during follow-up visits. The average age of the cases under consideration was 36.00 ± 13.23 years. In terms of gender, 4 out of the cases (40.00%) were females. During the initial session, the mean VSS scores in the PDL, PDL-BTA, and PDL-Triamcinolone groups were 7.90 ± 1.52, 7.10 ± 0.56, and 7.30 ± 0.24, subsequently. These scores decreased to 7.30 ± 1.34, 4.90 ± 1.37, and 4.30 ± 0.95 in the PDL, PDL-BTA, and PDL-Triamcinolone groups, respectively (P = 0.001). The group that received both PDL and BTA showed the most significant enhancement in pliability (P = 0.001) and regarding scar vascularity and height the most improvement was related to PDL-triamcinolone group (P = 0.01 and 0.001, respectively). In addition, the level of physician's satisfaction in the PDL-BTA and PDL-Triamcinolone groups were significantly higher than in the PDL group (P = 0.004). However, no significant difference was seen between the combined treatments. Finally, no significant side effects were observed in the studied methods during various treatment sessions. The findings of the study revealed that utilizing a combination of two modalities yielded better outcomes compared to a single treatment approach. Specifically, the combination of PDL and BTA demonstrated greater improvement in scar pliability. On the other hand, when considering scar vascularity and height, the combination of PDL with triamcinolone exhibited more significant enhancement.

Comparison of the wound healing and complications of zipper type closure adhesive tape and stapler for surgical wound suture: A randomized control, single-centre, open-label trial

Xkin closure is a newly developed medical suture device for lacerations and surgical wounds that can reduce scarring, pain and the risk of infection compared with conventional sutures or staplers. A randomized controlled study was performed to compare the wound healing effects and complications of Xkin closure with stapler closure. Fifty patients who underwent robot-assisted radical prostatectomy for prostate cancer were randomly assigned. Only the wound above the navel, which was extended to take out the prostate was targeted. The wound was examined at 2, 6 and 12 weeks after surgery, and the modified Vancouver Scar Scale (mVSS), scar height and side effects were assessed with a 3D skin analyser. Forty-six patients (23 Xkin, 23 Stapler) were analysed. The mVSS scores, vascularity and pliability were significantly lower in the Xkin group compared with the stapler group at the 12-week follow-up. No significant differences in the maximum peak and depth of the scars were detected between the two groups using 3D photographs at 12 weeks. Xkin is an effective wound closure method for improving scar outcomes. This method is expected to be widely used for surgical wounds and lacerations caused by trauma in daily life.

Comparing collagenase and silver sulfadiazine in deep second-degree burn treatment

The indications for collagenase ointment (CO) and its efficacy are not clearly established in the treatment of second-degree burn wounds. To evaluate the efficacy of CO versus silver sulfadiazine ointment (SSD) in the treatment of second-degree burn wounds. A total of 170 eligible patients with deep second-degree burns, aged 18-65 years, with injuries occurring within 48-96 h, and having a total wound area of less than 30% of the total body surface area were included from 5 centers in China. The primary outcome was the wound healing time, and the secondary outcomes were the clearance time of wound necrotic tissues, wound healing rate, and wound inflammation. The study included 85 patients in SSD group and 84 in CO group in the modified intention-to-treat (mITT) population. The median time of wound healing was comparable in both groups (10 days vs. 10.5 days P = 0.16). The time for wound necrotic tissue removal was significantly shortened by CO compared with SSD (5 vs. 10 days P < 0.01). Wound inflammation, pain, wound healing rate, and scar were compared with SSD (all P-values > 0.05). No adverse events, such as infection or allergic reactions to the drugs and materials used, were reported. Both CO and SSD could heal the burn wounds at 10 days of treatment. However, CO significantly shortened the time of wound necrotic tissue removal by 5 days. Trial Registration: ChiCTR2100046971.

Neuropathic pain in burn patients - A common problem with little literature: A systematic review

BACKGROUND

The prevalence of neuropathic pain (NP) in burn patients is reported in the literature to be as high as 80%1. Given the complexity of NP in burn patients and the wide range of treatments available, a systematic review of the literature is warranted to summarize our current understanding of management and treatment of NP in this population.

METHODS

This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The following databases were queried to identify relevant articles: PubMed, Cochrane, Embase, Scopus, Ovid, and Web of Science. The main outcome measures were incidence and management of NP. Secondary outcomes included risk factors for NP.

RESULTS

Included articles presented findings from 11 different countries, capturing outcomes for 4366 patients. Risk factors for neuropathic pain in burn patients were identified, including older age, alcohol and substance abuse, current daily smoking, greater % total body surface area burns (TBSA), and longer hospitalizations. Pharmacologic treatments included gabapentin/pregabalin (n = 7), ascorbic acid (n = 1), and lidocaine (n = 1). Overall, the studies showed varied results regarding the efficacy of pharmacological treatments. While certain studies demonstrated gabapentanoids to be effective in reducing neuropathic symptoms, others found conflicting results. With regards to non-pharmacologic treatments, electroconvulsive therapy (n = 1), electropuncture (n = 1), nerve release/reconstruction (n = 2), and somatosensory feedback rehabilitation (n = 1) were used and demonstrated promise in reducing pain intensity and improving functionality.

CONCLUSIONS

Despite NP afflicting the majority of burn patients long after their injury, this systematic review demonstrates insufficient evidence on the pathophysiology, outcomes, and risk factors in NP, as well as the efficacy of various therapies. Future prospective and randomized studies evaluating the etiology of these factors can substantially improve our treatment strategies. This can allow for the development of well-delineated and evidence-based protocols in NP management in hopes of improving quality of life and both psychological and physical function in burn patients.

Neuropathic Pain After Burn Injury: A Severe and Common Problem in Recovery

OBJECTIVE

The aim of this study was to address the limited understanding of neuropathic pain (NP) among burn survivors by comprehensively examining its prevalence and related factors on a national scale using the Burn Model System (BMS) National Database.

BACKGROUND

NP is a common but underexplored complaint among burn survivors, greatly affecting their quality of life and functionality well beyond the initial injury. Existing data on NP and its consequences in burn survivors are limited to select single-institution studies, lacking a comprehensive national perspective.

METHODS

The BMS National Database was queried to identify burn patients responding to NP-related questions at enrollment, 6 months, 12 months, 2 years, and 5 years postinjury. Descriptive statistics and regression analyses were used to explore associations between demographic/clinical characteristics and self-reported NP at different time points.

RESULTS

There were 915 patients included for analysis. At discharge, 66.5% of patients experienced NP in their burn scars. Those with NP had significantly higher Patient-Reported Outcomes Measurement Information System 29 (PROMIS-29) pain inference, itch, anxiety, depression, and sleep disturbance scores and were less able to partake in social roles. Multiple logistic regression revealed male sex, % total body surface area, and moderate-to-severe pain as predictors of NP at 6 months. At 12 months, % total body surface area and moderate-to-severe pain remained significant predictors, while ethnicity and employment status emerged as significant predictors at 24 months.

CONCLUSIONS

This study highlights the significant prevalence of NP in burn patients and its adverse impacts on their physical, psychological, and social well-being. The findings underscore the necessity of a comprehensive approach to NP treatment, addressing both physical symptoms and psychosocial factors.

Morphine (10, 20 mg) in a Postoperative Dressing Used with Patients After Surgical Debridement of Burn Wounds: A Prospective, Double-Blinded, Randomized Controlled Trial

Objective: This is the first clinical trial to evaluate the analgesic effect of 10 and 20 mg of morphine used in a postoperative dressing with patients after surgical debridement of burn wounds. Approach: In this randomized controlled trial, 20 adult patients with third-degree flame burns, who had undergone surgical debridement under general anesthesia, were randomly assigned to either group A, whose members were treated with a burn dressing that contained 10 mg of morphine, or group B, whose members were treated with a burn dressing that contained 20 mg of morphine; the dressing was also soaked with octenidine and phenoxyethanol in the case of both groups. The plasma morphine concentrations were measured 1, 2, 3, and 6 h after surgery, while the level of pain intensity was determined on the Numeric Pain Rating Scale (NRS), and the occurrence of side effects was observed. Results: The serum morphine concentration levels were very low, but statistically different between the two groups at all time points. The NRS value was similar in both groups at all time points (p > 0.05). Despite this, in group B, the NRS value was 0 in all patients in postoperative hours 1, 2, and 3. No adverse effect of morphine sulfate was observed in any patient. Innovation: This project is the first clinical study to have demonstrated that morphine administered in dressings in concentrations of 0.02-0.08 mg/mL significantly reduces the occurrence of pain. Conclusion: The use of morphine in dressings after surgical treatment of burn wounds is very effective when it comes to pain management and is safe for the patient.

Analgesic Efficacy of Oxycodone in Postoperative Dressings after Surgical Treatment of Burn Wounds: A Randomised Controlled Trial

INTRODUCTION

This study aimed to assess the analgesic efficacy of oxycodone at doses of 10 mg and 20 mg in dressings after surgery of burn wounds.

MATERIAL AND METHODS

Twenty adult patients who underwent surgical treatment of third-degree burn wounds under general anaesthesia were included. Burn wounds were treated with dressings, to which oxycodone was added at 20 mg in Group 1 and 10 mg in Group 2. After the surgery, plasma oxycodone and noroxycodone concentrations were assayed, and pain intensity was assessed with Numerical Rating Scale (NRS).

RESULTS

In Group 1, no patient reported pain; in Group 2, four patients reported pain. The pain intensity, according to NRS, was 1-8. Plasma concentration of oxycodone in the blood serum was in the range of 1.24-3.15 ng/mL and 1.09-1.28 ng/mL in Group 1 and Group 2, respectively. Noroxycodone was not detected in the plasma. Adverse effects were not observed in any of the treated patients.

CONCLUSIONS

Oxycodone in dressings provides patients with adequate and safe analgesia.

Hypertrophic Scar

Hypertrophic scars frequently develop post-burn, and are characterized by their pruritic, painful, raised, erythematous, dyschromic, and contractile qualities. This article aims to synthesize knowledge on the clinical and molecular development, evolution, management, and measurement of hypertrophic burn scar for both patient and clinician knowledge.

Wnt4 increases the thickness of the epidermis in burn wounds by activating canonical Wnt signalling and decreasing the cell junctions between epidermal cells

BACKGROUND

Burn wound healing is a complex process and the role of Wnt ligands varies in this process. Whether and how Wnt4 functions in burn wound healing is not well understood. In this study, we aim to reveal the effects and potential mechanisms of Wnt4 in burn wound healing.

METHODS

First, the expression of Wnt4 during burn wound healing was determined by immunofluorescence, Western blotting and qPCR. Then, Wnt4 was overexpressed in burn wounds. The healing rate and healing quality were analysed by gross photography and haematoxyline and eosin staining. Collagen secretion was observed by Masson staining. Vessel formation and fibroblast distribution were observed by immunostaining. Next, Wnt4 was knocked down in HaCaT cells. The migration of HaCaT cells was analysed by scratch healing and transwell assays. Next, the expression of β-catenin was detected by Western blotting and immunofluorescence. The binding of Frizzled2 and Wnt4 was detected by coimmunoprecipitation and immunofluorescence. Finally, the molecular changes induced by Wnt4 were analysed by RNA sequencing, immunofluorescence, Western blotting and qPCR in HaCaT cells and burn wound healing tissues.

RESULTS

The expression of Wnt4 was enhanced in burn wound skin. Overexpression of Wnt4 in burn wound skin increased the thickness of epidermis. Collagen secretion, vessel formation and fibroblast distribution were not significantly impacted by Wnt4 overexpression. When Wnt4 was knocked down in HaCaT cells, the ratio of proliferating cells decreased, the ratio of apoptotic cells increased and the ratio of the healing area in the scratch healing assay to the number of migrated cells in the transwell assay decreased. The nuclear translocation of β-catenin decreased in shRNA of Wnt4 mediated by lentivirus-treated HaCaT cells and increased in Wnt4-overexpressing epidermal cells. RNA-sequencing analysis revealed that cell junction-related signalling pathways were significantly impacted by Wnt4 knockdown. The expression of the cell junction proteins was decreased by the overexpression of Wnt4.

CONCLUSIONS

Wnt4 promoted the migration of epidermal cells. Overexpression of Wnt4 increased the thickness of the burn wound. A potential mechanism for this effect is that Wnt4 binds with Frizzled2 and increases the nuclear translocation of β-catenin, thus activating the canonical Wnt signalling pathway and decreasing the cell junction between epidermal cells.

An Updated Review of Hypertrophic Scarring

Hypertrophic scarring (HTS) is an aberrant form of wound healing that is associated with excessive deposition of extracellular matrix and connective tissue at the site of injury. In this review article, we provide an overview of normal (acute) wound healing phases (hemostasis, inflammation, proliferation, and remodeling). We next discuss the dysregulated and/or impaired mechanisms in wound healing phases that are associated with HTS development. We next discuss the animal models of HTS and their limitations, and review the current and emerging treatments of HTS.

Researches on cognitive sequelae of burn injury: Current status and advances

Burn injury is a devastating disease with high incidence of disability and mortality. The cognitive dysfunctions, such as memory defect, are the main neurological sequelae influencing the life quality of burn-injured patients. The post-burn cognitive dysfunctions are related to the primary peripheral factors and the secondary cerebral inflammation, resulting in the destruction of blood-brain barrier (BBB), as is shown on Computed Tomography (CT) and magnetic resonance imaging examinations. As part of the neurovascular unit, BBB is vital to the nutrition and homeostasis of the central nervous system (CNS) and undergoes myriad alterations after burn injury, causing post-burn cognitive defects. The diagnosis and treatment of cognitive dysfunctions as burn injury sequelae are of great importance. In this review, we address the major manifestations and interventions of post-burn cognitive defects, as well as the mechanisms involved in memory defect, including neuroinflammation, destruction of BBB, and hormone imbalance.

Enhanced Antimicrobial Activity of Silver Sulfadiazine Cosmetotherapeutic Nanolotion for Burn Infections

Burns are highly traumatizing injuries that can be complicated by various microbial infections, leading to morbidity and mortality. The ultimate goal of burn therapy is to prevent any microbial infection and rapid wound healing with epithelization. The current study aimed to develop and investigate the potential of nanoemulsion-based cosmetotherapeutic lotion of silver sulfadiazine (SSD) for increased antimicrobial activity to treat burn injuries. Silver sulfadiazine is the standard topical treatment for burn patients, but is allied with major limitations of poor solubility, low bioavailability, and other hematologic effects, hindering its pharmaceutical applications. The nanoformulation was fabricated through the ultrasonication technique and optimized by selecting various parameters and concentrations for the formation of water-in-oil (w/o) emulsion. The optimized formulation depicts a smaller particle size of 213 nm with an encapsulation efficiency of approx. 80%. Further, nanoemulsion-based SSD lotion by utilizing argan oil as a cosmetotherapeutic agent was prepared for scar massaging with improved permeation properties. The designed cosmeceutical formulation was characterized in terms of physical appearance, refractive index, particle size, encapsulation efficiency, and biocompatibility. The compatibility of the formulation ingredients were determined through FTIR (Fourier Transform Infrared Spectroscopy). The formulated nanolotion containing SSD demonstrated superior antimicrobial activities against different bacterial strains in comparison to commercialized burn creams.