The recovery of post-burn hypertrophic scar in a monitored pressure therapy intervention programme and the timing of intervention

Interventions for postburn pruritus

BACKGROUND

Postburn pruritus (itch) is a common and distressing symptom experienced on healing or healed burn or donor site wounds. Topical, systemic, and physical treatments are available to control postburn pruritus; however, it remains unclear how effective these are.

OBJECTIVES

To assess the effects of interventions for treating postburn pruritus in any care setting.

SEARCH METHODS

In September 2022, 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 and scanned references of relevant publications to identify eligible trials. There were no restrictions with respect to language, publication date, or study setting.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that enrolled people with postburn pruritus to compare an intervention for postburn pruritus with any other intervention, placebo or sham intervention, or no intervention.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included 25 RCTs assessing 21 interventions with 1166 randomised participants. These 21 interventions can be grouped into six categories: neuromodulatory agents (such as doxepin, gabapentin, pregabalin, ondansetron), topical therapies (such as CQ-01 hydrogel, silicone gel, enalapril ointment, Provase moisturiser, beeswax and herbal oil cream), physical modalities (such as massage therapy, therapeutic touch, extracorporeal shock wave therapy, enhanced education about silicone gel sheeting), laser scar revision (pulsed dye laser, pulsed high-intensity laser, fractional CO2 laser), electrical stimulation (transcutaneous electrical nerve stimulation, transcranial direct current stimulation), and other therapies (cetirizine/cimetidine combination, lemon balm tea). Most RCTs were conducted at academic hospitals and were at a high risk of performance, attrition, and detection bias. While 24 out of 25 included studies reported change in burn-related pruritus, secondary outcomes such as cost-effectiveness, pain, patient perception, wound healing, and participant health-related quality of life were not reported or were reported incompletely. Neuromodulatory agents versus antihistamines or placebo There is low-certainty evidence that doxepin cream may reduce burn-related pruritus compared with oral antihistamine (mean difference (MD) -2.60 on a 0 to 10 visual analogue scale (VAS), 95% confidence interval (CI) -3.79 to -1.42; 2 studies, 49 participants). A change of 2 points represents a minimal clinically important difference (MCID). Due to very low-certainty evidence, it is uncertain whether doxepin cream impacts the incidence of somnolence as an adverse event compared to oral antihistamine (risk ratio (RR) 0.64, 95% CI 0.32 to 1.25; 1 study, 24 participants). No data were reported on pain in the included study. There is low-certainty evidence that gabapentin may reduce burn-related pruritus compared with cetirizine (MD -2.40 VAS, 95% CI -4.14 to -0.66; 1 study, 40 participants). A change of 2 points represents a MCID. There is low-certainty evidence that gabapentin reduces the incidence of somnolence compared to cetirizine (RR 0.02, 95% CI 0.00 to 0.38; 1 study, 40 participants). No data were reported on pain in the included study. There is low-certainty evidence that pregabalin may result in a reduction in burn-related pruritus intensity compared with cetirizine with pheniramine maleate (MD -0.80 VAS, 95% CI -1.24 to -0.36; 1 study, 40 participants). A change of 2 points represents a MCID. There is low-certainty evidence that pregabalin reduces the incidence of somnolence compared to cetirizine (RR 0.04, 95% CI 0.00 to 0.69; 1 study, 40 participants). No data were reported on pain in the included study. There is moderate-certainty evidence that ondansetron probably results in a reduction in burn-related pruritus intensity compared with diphenhydramine (MD -0.76 on a 0 to 10 numeric analogue scale (NAS), 95% CI -1.50 to -0.02; 1 study, 38 participants). A change of 2 points represents a MCID. No data were reported on pain and adverse events in the included study. Topical therapies versus relevant comparators There is moderate-certainty evidence that enalapril ointment probably decreases mean burn-related pruritus compared with placebo control (MD -0.70 on a 0 to 4 scoring table for itching, 95% CI -1.04 to -0.36; 1 study, 60 participants). No data were reported on pain and adverse events in the included study. Physical modalities versus relevant comparators Compared with standard care, there is low-certainty evidence that massage may reduce burn-related pruritus (standardised mean difference (SMD) -0.86, 95% CI -1.45 to -0.27; 2 studies, 166 participants) and pain (SMD -1.32, 95% CI -1.66 to -0.98). These SMDs equate to a 4.60-point reduction in pruritus and a 3.74-point reduction in pain on a 10-point VAS. A change of 2 VAS points in itch represents a MCID. No data were reported on adverse events in the included studies. There is low-certainty evidence that extracorporeal shock wave therapy (ESWT) may reduce burn-related pruritus compared with sham stimulation (SMD -1.20, 95% CI -1.65 to -0.75; 2 studies, 91 participants). This equates to a 5.93-point reduction in pruritus on a 22-point 12-item Pruritus Severity Scale. There is low-certainty evidence that ESWT may reduce pain compared with sham stimulation (MD 2.96 on a 0 to 25 pressure pain threshold (PPT), 95% CI 1.76 to 4.16; 1 study, 45 participants). No data were reported on adverse events in the included studies. Laser scar revision versus untreated or placebo controls There is moderate-certainty evidence that pulsed high-intensity laser probably results in a reduction in burn-related pruritus intensity compared with placebo laser (MD -0.51 on a 0 to 1 Itch Severity Scale (ISS), 95% CI -0.64 to -0.38; 1 study, 49 participants). There is moderate-certainty evidence that pulsed high-intensity laser probably reduces pain compared with placebo laser (MD -3.23 VAS, 95% CI -5.41 to -1.05; 1 study, 49 participants). No data were reported on adverse events in the included studies.

AUTHORS' CONCLUSIONS

There is moderate to low-certainty evidence on the effects of 21 interventions. Most studies were small and at a high risk of bias related to blinding and incomplete outcome data. Where there is moderate-certainty evidence, practitioners should consider the applicability of the evidence for their patients.

Ultrasound measurement of traumatic scar and skin thickness: a scoping review of evidence across the translational pipeline of research-to-practice

OBJECTIVES

To identify the ultrasound methods used in the literature to measure traumatic scar thickness, and map gaps in the translation of these methods using evidence across the research-to-practice pipeline.

DESIGN

Scoping review.

DATA SOURCES

Electronic database searches of Ovid MEDLINE, Embase, Cumulative Index of Nursing and Allied Health Literature and Web of Science. Grey literature searches were conducted in Google. Searches were conducted from inception (date last searched 27 May 2022).

DATA EXTRACTION

Records using brightness mode (B-mode) ultrasound to measure scar and skin thickness across the research-to-practice pipeline of evidence were included. Data were extracted from included records pertaining to: methods used; reliability and measurement error; clinical, health service, implementation and feasibility outcomes; factors influencing measurement methods; strengths and limitations; and use of measurement guidelines and/or frameworks.

RESULTS

Of the 9309 records identified, 118 were analysed (n=82 articles, n=36 abstracts) encompassing 5213 participants. Reporting of methods used was poor. B-mode, including high-frequency (ie, >20 MHz) ultrasound was the most common type of ultrasound used (n=72 records; 61% of records), and measurement of the combined epidermal and dermal thickness (n=28; 24%) was more commonly measured than the epidermis or dermis alone (n=7, 6%). Reliability of ultrasound measurement was poorly reported (n=14; 12%). The scar characteristics most commonly reported to be measured were epidermal oedema, dermal fibrosis and hair follicle density. Most records analysed (n=115; 97%) pertained to the early stages of the research-to-practice pipeline, as part of research initiatives.

CONCLUSIONS

The lack of evaluation of measurement initiatives in routine clinical practice was identified as an evidence gap. Diverse methods used in the literature identified the need for greater standardisation of ultrasound thickness measurements. Findings have been used to develop nine methodological considerations for practitioners to guide methods and reporting.

Treatment of external auditory canal stenosis and atresia after transcanal endoscopic ear surgery

PURPOSE

To discuss the treatment of external auditory canal stenosis or atresia occurring as a complication of transcanal endoscopic ear surgery.

MATERIALS AND METHODS

We retrospectively analyzed the medical records of 11 patients who developed external auditory canal stenosis or atresia after undergoing transcanal endoscopic ear surgery. The 10 patients with stenosis were treated with external auditory canal expansion via drainage tube insertion; 2 of these patients further received local injections of triamcinolone acetonide. One patient with atresia was treated with meatoplasty surgery followed by tube insertion and triamcinolone acetonide injection.

RESULTS

The stenosis/atresia improved in all patients, and the external auditory canal was unobstructed without restenosis.

CONCLUSIONS

Stenosis/atresia of the external auditory canal after transcanal endoscopic ear surgery should be treated with dilation therapy/meatoplasty in a timely manner to prevent progressive hyperplasia of the scar and regain a normal-sized ear canal.

Pressure therapy for scars: Myth or reality? A systematic review

BACKGROUND

Hypertrophic scarring is a deviate occurrence after wound closure and is a common burn sequela. The mainstay of scar treatment consists of a trifold approach: hydration, UV-protection and the use of pressure garments with or without extra paddings or inlays to provide additional pressure. Pressure therapy has been reported to induce a state of hypoxia and to reduce the expression pattern of transforming growth factor-β1 (TGF-β1), therefore limiting the activity of fibroblasts. However, pressure therapy is said to be largely based on empirical evidence and a lot of controversy concerning the effectiveness still prevails. Many variables influencing its effectivity, such as adherence to treatment, wear time, wash frequency, number of available pressure garment sets and amount of pressure remain only partially understood. This systematic review aims to give a complete and comprehensive overview of the currently available clinical evidence of pressure therapy.

METHODS

A systematic search for articles concerning the use of pressure therapy in the treatment and prevention of scars was performed in 3 different databases (Pubmed, Embase, and Cochrane library) according to the PRISMA statement. Only case series, case-control studies, cohort studies, and RCTs were included. The qualitative assessment was done by 2 separate reviewers with the appropriate quality assessment tools.

RESULTS

The search yielded 1458 articles. After deduplication and removal of ineligible records, 1280 records were screened on title and abstract. Full text screening was done for 23 articles and ultimately 17 articles were included. Comparisons between pressure or no pressure, low vs high pressure, short vs long duration and early vs late start of treatment were investigated.

CONCLUSION

There is sufficient evidence that indicates the value of prophylactic and curative use of pressure therapy for scar management. The evidence suggests that pressure therapy is capable of improving scar color, thickness, pain, and scar quality in general. Evidence also recommends commencing pressure therapy prior to 2 months after injury, and using a minimal pressure of 20-25 mmHg. To be effective, treatment duration should be at least 12 months and even preferably up to 18-24 months. These findings were in line with the best evidence statement by Sharp et al. (2016).

Inhibition of ANGPT2 activates autophagy during hypertrophic scar formation via PI3K/AKT/mTOR pathway

BACKGROUND

Hypertrophic scar (HS), a fibroproliferative disorder caused by aberrant wound healing following skin injuries such as burns, lacerations and surgery, is characterized by invasive proliferation of fibroblasts and excessive extracellular matrix (ECM) accumulation. The dysregulation of autophagy is the pathological basis of HS formation. Previously, angiopoietin-2 (ANGPT2) was found to be overexpressed in HS fibroblasts (HSFs) compared with normal skin fibroblasts. However, whether ANGPT2 participates in the process of HS formation and the potential molecular mechanisms are not clear.

OBJECTIVE

This study is intended to figure out the role of ANGPT2 and ANGPT2-mediated autophagy during the development of HS.

METHODS

RT-qPCR was used to detect ANGPT2 expression in HS tissues and HSFs. HSFs were transfected with sh-ANGPT2 to knock down ANGPT2 expression and then treated with MHT1485, the mTOR agonist. The effects of sh-ANGPT2 or MHT1485 on the proliferation, migration, autophagy and ECM accumulation of HSFs were evaluated by CCK-8 assay, Transwell assay and western blotting. The expression of PI3K/Akt/mTOR pathway-related molecules (p-PI3K, p-Akt and p-mTOR) was assessed by western blotting.

RESULTS

ANGPT2 expression was markedly upregulated in HS tissues and HSFs. ANGPT2 knockdown decreased the expression of p-PI3K, p-Akt and p-mTOR. ANGPT2 knockdown activated autophagy and inhibited the proliferation, migration, and ECM accumulation of HSFs. Additionally, the treatment of MHT1485, the mTOR agonist, on ANGPT2-downregulated HSFs, partially reversed the influence of ANGPT2 knockdown on HSFs.

STUDY LIMITATIONS

The study lacks the establishment of more stable in vivo animal models of HS for investigating the effects of ANGPT2 on HS formation in experimental animals.

CONCLUSIONS

ANGPT2 downregulation represses growth, migration, and ECM accumulation of HSFs via autophagy activation by suppressing the PI3K/Akt/mTOR pathway. Our study provides a novel potential therapeutic target for HS.

Clinical Utility of the Portable Pressure-Measuring Device for Compression Garment Pressure Measurement on Hypertrophic Scars by Burn Injury during Compression Therapy

Compression therapy for burn scars can accelerate scar maturation and improve clinical symptoms (pruritus and pain). This study objectively verified the effect of pressure garment therapy in maintaining a therapeutic pressure range for hypertrophic scars. Sixty-five participants (aged 20~70 years) with partial- or full-thickness burns, Vancouver scar scale score of ≥4, and a hypertrophic scar of ≥4 cm × 4 cm were enrolled. Compression pressure was measured weekly using a portable pressure-monitoring device to regulate this pressure at 15~25 mmHg for 2 months. In the control group, the compression garment use duration and all other burn rehabilitation measures were identical except for compression monitoring. No significant difference was noted in the initial evaluations between the two groups (p > 0.05). The improvements in the amount of change in scar thickness (p = 0.03), erythema (p = 0.03), and sebum (p = 0.02) were significantly more in the pressure monitoring group than in the control group. No significant differences were noted in melanin levels, trans-epidermal water loss, or changes measured using the Cutometer® between the two groups. The efficacy of compression garment therapy for burn-related hypertrophic scars can be improved using a pressure-monitoring device to maintain the therapeutic range.

Traditional Chinese medicine for hypertrophic scars—A review of the therapeutic methods and potential effects

Hypertrophic scar (HS) is a typical pathological response during skin injury, which can lead to pain, itching, and contracture in patients and even affect their physical and mental health. The complexity of the wound healing process leads to the formation of HS affected by many factors. Several treatments are available for HS, whereas some have more adverse reactions and can even cause new injuries with exacerbated scarring. Traditional Chinese Medicine (TCM) has a rich source, and most botanical drugs have few side effects, providing new ideas and methods for treating HS. This paper reviews the formation process of HS, the therapeutic strategy for HS, the research progress of TCM with its relevant mechanisms in the treatment of HS, and the related new drug delivery system of TCM, aiming to provide ideas for further research of botanical compounds in the treatment of HS, to promote the discovery of more efficient botanical candidates for the clinical treatment of HS, to accelerate the development of the new drug delivery system and the final clinical application, and at the same time, to promote the research on the anti-HS mechanism of multiherbal preparations (Fufang), to continuously improve the quality control and safety and effectiveness of anti-HS botanical drugs in clinical application.

Pressure by design: How to improve the consistency of pressure garments in the clinical environment and implement a simple method for gathering evidence to establish efficacy

Pressure garments are used to treat scars after major trauma including burns. However, the ideal pressure for treatment is not known. Pressures exerted are not routinely measured and garments exert a wide range of pressures. Therefore, current treatment and its efficacy are variable. Pressure Garment Design Tools were introduced in 2012 but their application in hospitals has not been reported. A Garment Dimension and Pressure Calculator was used to audit pressures delivered by 8 pressure garments made for children using the hospital department's standard reduction factor. The tool was easy to use and showed that pressures exerted by standard garments ranged from 15 to 54 mmHg with highest pressures exerted on wrists. Results of our pilot study indicated that the Garment Dimension and Pressure Calculator was slightly quicker to use than our normal manual process for calculating garment dimensions and enabled easy auditing of past treatment. The Pressure Garment Design Tool was easy to use and calculated garments that exerted the mean target pressures of 15 mmHg and 25 mmHg, improving consistency. Pressures exerted by garments were difficult and time consuming to measure with the Picopress sensor. Pressure was not distributed evenly around the limbs and measurements were inaccurate on the smallest limbs.

A six-herb Chinese medicine composition ointment as a promising candidate for treatment of hypertrophic scars

Objective

To study the anti-hypertrophic scar effect of the six-herb Chinese medicine composition (SCMC) ointment on the rabbit ear hypertrophic scar models.

Methods

The optimal formulation of SCMC ointment matrix was screened by the orthogonal designs and a series of evaluation tests. The SCMC ointment was prepared through emulsifying method. The rabbit ear hypertrophic scar models were established and used to investigate the anti-hypertrophic scar effect of SCMC ointment.

Results

Our results demonstrated that all the quality control indications of the SCMC ointment met the requirements. Anti-hypertrophic scar activity results showed that all the rabbit ear scar tissues appeared different degrees of shrink and fading, and took an unobvious but palpable shift from hard to soft texture with the low, middle and high concentration SCMC ointments treatments in vivo. Additionally, on 21st day the scar area and thickness in different concentrations of SCMC ointment groups were significantly reduced than control group, in a concentration-dependent manner. The immunohistochemical results also indicated that the SCMC ointment had good anti-hypertrophic scar properties and could inhibit hypertrophic scar formation.

Conclusion

The SCMC ointment could improve the blood circulation condition of hypertrophic scar tissues. Our research has demonstrated the Chinese medicine composition ointment with good anti-hypertrophic scar properties that could be used to treat hypertrophic scars. Meanwhile, it provides a theoretical basis for further clinical application.

Comparison between the portable pressure measuring device and PicoPress® for garment pressure measurement on hypertrophic burn scar during compression therapy

PURPOSE

The current standard treatment for hypertrophic scars following burn injury is pressure garment therapy. The experimenters developed the novel portable pressure measuring device using silicon piezoresistive sensors. As PicoPress® is the most accurate (i.e., lowest variation and error) manometric sensor for pressure measurement, we sought to compare and examine the accuracy of the novel device regarding in vitro pressure measurements at the hypertrophic scar-pressure garment interface.

METHODS

The novel device was designed to operate in non-corrosive media, such as air. The device can use up to six pressure sensing points and was developed to adjust the number of pressure sensors according to the size of the scar. Pressure measurements were acquired through a readout circuit consisting of an analog-to-digital converter, a microprocessor, and a Bluetooth transmission module for wireless data transmission to an external device. All signals were converted into mean pressure expressed in millimeters of mercury (mmHg). The mean pressure values measured by the sensors were compared to those obtained from PicoPress®. 55 garment pressures recordings were obtained from the sensors over this study conducted in 2018-February 2020. We then analyzed the test-retest reliability using the intraclass correlation coefficients (ICC). PicoPress® was also employed in the same pressure garments for obtaining similar measurements. A two way random effects model ICC with 95% confidence intervals was used to compare the mean pressure values obtained from the silicon piezoresistive sensors to the PicoPress® measurements.

RESULTS

The test-retest reliability of the pressure sensors was close to the acceptable level for clinical use regarding stationary interface pressure measurement (ICC = 0.99, 95% CI 0.990-0.997). The mean pressure obtained from the silicon piezoresistive pressure sensors showed an accordance with the measurements from PicoPress® (ICC = 0.97, 95% CI 0.947-0.985).

CONCLUSION

The novel device may present a viable alternative to PicoPress® for garment pressure measurements. In addition, the novel device improves adaptability to the hypertrophic scar shape and size. Complementary characteristics such as wireless transmission to an external device may allow burn patients to continuously wear the device for real-time measurements during pressure garment therapy, thus improving existing devices including PicoPress®.

Heterogeneous Features of Keloids Assessed by Laser Speckle Contrast Imaging: A Cross-Sectional Study

BACKGROUND AND OBJECTIVES

Keloids are described as benign dermal fibroproliferative lesions, and vascularization may play a significant role in their pathogenesis. In this study, laser speckle contrast imaging (LSCI) was used to assess perfusion within keloids and surrounding skin, and perfusion of keloids at different stages was compared.

STUDY DESIGN/MATERIALS AND METHODS

A total of 59 patients with 110 untreated keloids on the anterior chest were enrolled in this study. Different keloid stages (progressive, stable, and regressive) were defined according to patients' descriptions of whether keloids became larger, stable, or smaller during the previous year. Vancouver Scar Scale (VSS) was assessed by a plastic surgeon, and patient reports on pain and itching were documented. LSCI was used to evaluate blood perfusion of keloids (K), skin adjacent to keloids (A), and nonadjacent skin (N). The mean perfusion of these regions was determined, and ratios (K/N, A/N) were calculated.

RESULTS

A heterogeneous perfusion map was observed among the keloid groups, as well as within each keloid. A positive correlation was found between keloid perfusion and VSS. There were 62 (56.4%) keloids in the progressive stage, 33 (30.0%) keloids in the stable stage, and 15 (13.6%) keloids in the regressive stage. The mean K/N ratios in the progressive, stable, and regressive stages were 2.3 ± 0.5, 1.8 ± 0.3, and 1.5 ± 0.5, respectively. The mean A/N ratios were 1.2 ± 0.4, 1.2 ± 0.2, and 1.0 ± 0.5, respectively. Within each keloid, significantly higher perfusion was noted in the keloid and adjacent skin compared with nonadjacent skin.

CONCLUSION

These results indicate that LSCI is a promising technique for evaluating keloid blood perfusion and distinguishing heterogeneous keloids. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Strategies to prevent hypertrophic scar formation: a review of therapeutic interventions based on molecular evidence

Once scar tissues mature, it is impossible for the surrounding tissue to regenerate normal dermal tissue. Therefore, it is essential to understand the fundamental mechanisms and establish effective strategies to inhibit aberrant scar formation. Hypertrophic scar formation is considered a result of the imbalance between extracellular matrix synthesis and degradation during wound healing. However, the underlying mechanisms of hypertrophic scar development are poorly understood. The purpose of this review was to outline the management in the early stage after wound healing to prevent hypertrophic scar formation, focusing on strategies excluding therapeutic agents of internal use. Treatment aimed at molecular targets, including cytokines, will be future options to prevent and treat hypertrophic scars. More basic studies and clinical trials, including combination therapy, are required to investigate the mechanisms and prevent hypertrophic scar formation.

Feasibility of Pure Silk for the Treatment of Large Superficial Burn Wounds Covering Over 10% of the Total Body Surface

Large, superficial burn wounds require many painful dressing changes and, thus, dressings that can stay on the wound and peel off during re-epithelization such as Biobrane® and Suprathel® are preferred, but they are costly. Natural silk has shown good outcomes with respect to wound healing, scarring, and patient satisfaction. This study aimed to evaluate the efficacy of natural silk compared with that of initially used dressings for the treatment of superficial burn wounds greater than 10% of the TBSA. Patients with superficial burns covering >10% of the TBSA were treated with pure silk for the first time (treatment group). Complications during wound healing with respect to the need for further surgery and scarring were compared with those of patients with similar burns of more than 10% TBSA and treated with nylon mesh and collagen instead of silk (treatment group). The treatment and control group comprised 25 and 13 patients, respectively. In total, 88% of patients in the treatment group did not require further treatment, while two patients with chemical burns needed further surgeries. Moreover, patients reported high satisfaction with respect to scarring and aesthetic outcome. Meanwhile, 85% of patients in the control group healed without further surgery and showed higher median hypopigmentation and hyperpigmentation after 12 months. Silk is an effective wound dressing for the treatment of large superficial burn wounds. It avoids painful dressing changes and yields satisfactory aesthetic outcomes. However, especially in large burns, careful initial wound depth assessment is crucial to prevent infection and reoperations.