Using Physiology to Improve Surgical Wound Outcomes

Efficiency of an algorithm for the prevention of sternal infection after cardiac surgery in children under 1 year of age: A single-center retrospective study

Background

Sternal infection is one of the most challenging complications to manage after heart surgery. The aim of our study is to evaluate the effectiveness of a developed algorithm for preventing sternal infection in pediatric patients after surgery for congenital heart disease (CHD).

Methods

We conducted a single-center study examining the treatment of 478 children with CHD. Patients were divided into 2 groups, taking into account the application of a developed management algorithm. A multivariate logistic regression analysis was used to identify the factors influencing the development of sternal infection following heart surgery using median sternotomy.

Results

A developed algorithm was applied in 308 children. In total, there were 16 cases of sternal infection (3.34 %) across both groups. Deep wound infection developed in 6 patients (1.26 %). Sternal infection developed in 2 children (0.65 %) in the first group (in which the algorithm was applied) and 14 children (8.2 %) in the second group. Deep sternal infection developed in 1 patient in the first group (0.33 %) and in 5 patients in the second group (2.94 %). As a result, perioperative risk factors as postoperative resternotomy (OR 23.315; p < 0.001), delayed sternal closure (OR 9.087; p = 0.003), development of acute renal failure (OR 5.322; p = 0.018) were associated with increased risk of infection and application of the developed algorithm resulted in a significant reduction in risk (OR 0.032; p < 0.001).

Conclusion

The suggested method for the prevention of sternal infection has significantly reduced the incidence of sternal infection after cardiac surgery in children less than 1 year of age. In patients with moderate to high risk for surgical site infection, surgeons can enhance wound healing and prevent wound infections with simple, inexpensive, and readily available tools and techniques. Surgical aspects, topical use of antibiotics, prevention of peripheral vasoconstriction, maintenance of normal oxygen delivery rates, and an individual approach to intensive care are essential.

Affecting factors for abdominal incisional tension in surgery of dogs and cats

OBJECTIVE

Proper assessment of intraoperative abdominal incisional tension helps to select the appropriate sutures and suture method. Wound tension is usually thought to be associated with wound size, but few relevant articles have been reported. The aim of this study was to investigate the core factors influencing abdominal incisional tension and construct regression equations to judge incisional tension in clinical surgery.

METHODS

Medical records were collected from clinical surgical cases at the Teaching Animal Hospital of Nanjing Agricultural University from March 2022 to June 2022. The data collected mainly included the body weight, and the incisional length, margin, and tension. The core factors affecting abdominal wall incisional tension were screened by correlation analysis, random forest analysis, and multiple linear regression analysis.

RESULTS

Although correlation analysis showed that multiple same and deep layer abdominal incision parameters and body weight were significantly correlated with abdominal incisional tension. However, the same layer of abdominal incisional margin had the largest correlation coefficient. In random forest models, the abdominal incisional margin had the main contribution to the prediction of the same layer's abdominal incisional tension. In the multiple linear regression model, all incisional tension could be predicted by the same layer of abdominal incisional margin as the only independent variable, except for canine muscle and subcutaneous. The canine muscle and subcutaneous incisional tension were binary regressions with the same layer's abdominal incision margin and body weight.

CONCLUSION

The same layer's abdominal incisional margin is the core factor positively related to the abdominal incisional tension intraoperatively.

A Novel Effective Formulation of Bioactive Compounds for Wound Healing: Preparation, In Vivo Characterization, and Comparison of Various Postbiotics Cold Creams in a Rat Model

The wound is a break in the integrity of the skin produced by injury, illness, or operation. Wound healing is an essential dynamic biological/physiological process that occurs in response to tissue damage. The huge health, economic, and social effects of wounds on patients and societies necessitate the research to find novel potential therapeutic agents in order to promote wound healing. Postbiotics, the newest member of the biotics family, are valuable functional bioactive substances produced by probiotics through their metabolic activity, which have several beneficial properties, including immunomodulatory, anti-inflammatory, antimicrobial, and angiogenesis characteristics, resulting in acceleration of wound healing. In the current study, three topical cold cream formulations containing postbiotics obtained from Lactobacillus fermentum, Lactobacillus reuteri, or Bacillus subtilis sp. natto probiotic strains were prepared. The effectiveness and wound healing activity of the developed postbiotics cold cream formulations were investigated compared to cold cream without postbiotics and no treatment via wound closure investigation, hydroxyproline content assay, and histological assessment in 25 Sprague Dawley rats divided into five groups. Interestingly, analysis of the results revealed that all three formulations containing postbiotics significantly accelerated the wound healing process. However, in general, the Bacillus subtilis natto cold cream manifested a better wound healing property. The pleasing wound healing characteristics of the topical postbiotics cold creams through the in vivo experiment suggest that formulations containing postbiotics can be considered as a promising nominee for wound healing approaches.

Wound Healing: A Comprehensive Review

Wound healing is an intricate, tightly regulated process that is critical to maintaining the barrier function of skin along with preserving all other skin functions. This process can be influenced by a variety of modifiable and nonmodifiable factors. As wound healing takes place in all parts of the human body, this review focuses on cutaneous wound healing and highlights the classical wound healing phases. Alterations in any of these phases can promote chronic wound development and may impede wound healing.

Enhanced perfusion of elliptical wound closures using a novel adhesive suture retention device

BACKGROUND AND AIMS

The purpose of this investigation was to test the hypothesis that a novel adhesive retention suture device (ARSD) can increase perfusion at elliptical wound closures by distributing stress away from the suture site.

METHODS

Stress in the skin around a suture both with and without support from an ARSD was evaluated using a finite element model. A single-center, randomized split-scar comparison trial using laser speckle contrast analysis was used to quantify the perfusion at elliptical wound closures in human patients both with and without an ARSD.

RESULTS

The finite element model revealed that the ARSD promoted load transfer to the skin over a larger area, thus reducing the local stress and deformation in the skin around the suture site. Results from the split-scar study showed a mean improvement of 25% perfusion units with the ARSD, and the improvement was statistically significant (p = 0.002).

CONCLUSION

The reduction in local stress and enhanced perfusion around the suture site reveals the potential benefit of using an ARSD to enable more efficient healing by avoiding complications associated with both low perfusion and skin tearing, such as dehiscence, infection, and cheese wiring.

Methamphetamine Use is Associated with Increased Surgical Site Infections after Trauma Laparotomy

BACKGROUND

Methamphetamine (METH) use causes significant vasoconstriction, which can be severe enough to cause bowel ischemia. Methamphetamines have also been shown to alter the immune response. These effects could predispose METH users to poor wound healing, increased infections, and other post-operative complications. We hypothesized that METH users would have longer length of stay and higher rates of complications compared to non-METH users.

METHODS

The trauma registry for our urban Level 1 trauma center was searched for patients that received an exploratory laparotomy from 2016 to 2019. A total 204 patients met criteria and 52 (25.5%) were METH positive. Length of stay (LOS), ventilator days, abbreviated injury scale (AIS), and wound class were compared using nonparametric statistics. Age and injury severity score (ISS) were compared using a Student's t-test. A Chi Square or Fisher's Exact test was used to compare sex, mechanism of injury, and rates of infectious complications.

RESULTS

Methamphetamine-positive patients had a significantly higher rate of surgical site infections (7.4% versus 0%, P = 0.001). Patients that developed surgical site infection had equivalent rates of smoking and diabetes, as well as equivalent abdominal AIS and wound class compared to those who did not develop surgical site infection. Hospital and ICU LOS, ventilator days, ISS, and mortality were equivalent between METH positive and negative patients. Rates of other infectious complications were the same between groups.

CONCLUSIONS

Methamphetamine use is associated with an increased rate of surgical site infection after trauma laparotomy. Other serious complications and mortality were not affected by METH use.

Cloves (Syzygium aromaticum) fluid gel on healing of pododermatitis in rabbits

Wounds are damaging to quality life of confined animals, causing dysfunction in spinal, members injuries, and reduction in productive performance. This research investigated the clove antimicrobial and antioxidant activity on the healing of decubitus wounds (pododermatitis) of rabbits (Oryctolagus cuniculus). Adult animals were treated for 21 days every three days with a fluid gel spray in the wound region: control fluid gel without addition of clove (FGC0), fluid gel with addition of 1% clove powder (FGC1), and fluid gel with 2% clove powder (FGC2). Microbiological analysis for Escherichia coli and Pseudomonas spp. were performed during 21 days of experimental period. After this period, samples from treated skin were evaluated for histological analysis and evaluation of the healing process by spectroscopy (FTIR-ATR). Rabbits treated with FGC2 showed advanced healing and decreased tissue inflammation similar to healthy rabbits, while FGC0 rabbits showed a decrease in bacterial contamination without signs of healing. Both FGC1 and FGC2 rabbits demonstrated antimicrobial and antioxidant action against both bacteria tested, favoring the wound healing process. Considering the results, the use of fluid gel with 2% of clove powder (Syzigium aromaticum) based on the best antimicrobial, antioxidant and anti-inflammatory activities on healing of decubitus wounds (pododermatitis) of rabbits in commercial farming system.

Stimuli-Responsive Delivery of Growth Factors for Tissue Engineering

Growth factors (GFs) play a crucial role in directing stem cell behavior and transmitting information between different cell populations for tissue regeneration. However, their utility as therapeutics is limited by their short half-life within the physiological microenvironment and significant side effects caused by off-target effects or improper dosage. "Smart" materials that can not only sustain therapeutic delivery over a treatment period but also facilitate on-demand release upon activation are attracting significant interest in the field of GF delivery for tissue engineering. Three properties are essential in engineering these "smart" materials: 1) the cargo vehicle protects the encapsulated therapeutic; 2) release is targeted to the site of injury; 3) cargo release can be modulated by disease-specific stimuli. The aim of this review is to summarize the current research on stimuli-responsive materials as intelligent vehicles for controlled GF delivery; Five main subfields of tissue engineering are discussed: skin, bone and cartilage, muscle, blood vessel, and nerve. Challenges in achieving such "smart" materials and perspectives on future applications of stimuli-responsive GF delivery for tissue regeneration are also discussed.

Extracorporeal membrane oxygenation for acute respiratory distress syndrome in burn patients: a case series and literature update

Background

Acute respiratory distress syndrome (ARDS) has a reported incidence of 34–43% in ventilated burn patients and is associated with a mortality of 59% in the severe form. The use and experience with extracorporeal membrane oxygenation (ECMO) in burn patients developing ARDS are still limited. We present our results and discuss the significance of ECMO in treating burn patients.

Methods

A retrospective analysis of burn patients treated with ECMO for ARDS between January 2017 and January 2019 was performed. Demographic, clinical, and outcome data were collected and analyzed.

Results

Eight burn patients were treated at our institution with ECMO in the designated time period. Of these, all but one patient had inhalation injury, burn percentage of TBSA was 37 ± 23%, ABSI score was 8.4 ± 2, and R-Baux-score was 98 ± 21. Seven patients developed severe ARDS and one patient moderate ARDS according to the Berlin classification with a PaO₂/FiO₂ ratio upon initiation of ECMO therapy of 62 ± 22 mmHg. ECMO duration was 388 ± 283 h. Three patients died from severe sepsis while five patients survived to hospital discharge.

Conclusions

ECMO is a viable therapy option in burn patients developing severe ARDS and can contribute to survival rates similar to ECMO therapy in non-burn-associated severe ARDS. Consequently, patients with severe respiratory insufficiency with unsuccessful conventional treatment and suspected worsening should be transferred to burn units with the possibility of ECMO treatment to improve outcome.

The Influence of Preoperative Interventions on Postoperative Surgical Wound Healing in Patients Without Risk Factors: A Systematic Review

BACKGROUND

Poor wound healing and scar formation remain critical problems in daily surgical practice. Generally, most attention is paid to intra- and postoperative interventions to improve wound healing after surgery, while preoperative interventions remain unsatisfactorily explored.

OBJECTIVES

In this systematic review, the available literature on the beneficial effects of preoperative interventions on wound healing and scar formation have been summarized and compared.

METHODS

A comprehensive and systematic search has been conducted in MEDLINE, Pubmed, Embase, Web of Science, and Cochrane, supplemented by reference and citation tracking. All preoperative interventions and all clinically relevant outcome parameters have been considered for inclusion, due to the expected limited availability of literature.

RESULTS

A total of 13 studies were included, which were all randomized trials. No cohort studies or retrospective studies have been identified. All studies described different preoperative interventions and outcome parameters and could hence not be pooled and compared. Eight studies showed significantly better wound healing after a preoperative intervention. The individual studies have been summarized in this review.

CONCLUSIONS

This systemic review shows that preoperative interventions can be beneficial in improving wound healing and scar formation. In selected cases, wound healing was found to benefit from a higher preoperative body temperature, topical vitamin E application, and low patient stress levels.

LEVEL OF EVIDENCE 2

Evidence-Based Strategies to Reduce Postoperative Complications in Plastic Surgery

Reconstructive plastic surgery is vital in assisting patients with reintegration into society after events such as tumor extirpation, trauma, or infection have left them with a deficit of normal tissue. Apart from performing a technically sound operation, the plastic surgeon must stack the odds in the favor of the patient by optimizing them before and after surgery. The surgeon must look beyond the wound, at the entire patient, and apply fundamental principles of patient optimization. This article reviews the evidence behind the principles of patient optimization that are commonly used in reconstructive surgery patients.

Human gingiva transcriptome during wound healing

OBJECTIVES

To investigate the gene expression profile of human gingiva following surgical wounding.

METHODS

Ten volunteers had one side of the palate wounded. Five days later, biopsies were harvested from both wounded (healing gingiva) and contra-lateral site (normal gingiva). Tissue samples were processed for gene expression (RNA-Seq, real-time PCR) and immunohistochemistry. Gene set enrichment/pathway analysis was also performed.

RESULTS

Seven hundred genes were significantly differentially expressed in healing gingiva. Among genes with >twofold change (FC) in expression, 399 genes were up-regulated and 88 down-regulated, several not previously reported expressed in gingiva. Most increased in expression (≥30-FC) were MMP1, CCL18, SPP1, MUC21, CTHRC1, MMP10, and SERPINE1; most decreased (≥7-FC) were COCH, SIAH3, MT4, IGFL3, KY, and SYT16. Real-time PCR confirmed significantly changed mRNA levels for selective genes tested. Gene set enrichment analysis revealed several significantly enriched biological pathways. Immunohistochemistry confirmed protein expression of MUC21, CTHRC1, CTGF, and SYT16 in normal and healing gingiva.

CONCLUSIONS

This first comprehensive analysis of the human gingival transcriptome during surgical wound healing offers novel insights into the participating molecular and biological mechanisms. The present results could serve as basis for future investigations into gingival wound healing following surgical, traumatic, or other type of injury.

zWEDGI: Wounding and Entrapment Device for Imaging Live Zebrafish Larvae

Zebrafish, an established model organism in developmental biology, is also a valuable tool for imaging wound healing in space and time with cellular resolution. However, long-term imaging of wound healing poses technical challenges as wound healing occurs over multiple temporal scales. The traditional strategy of larval encapsulation in agarose successfully limits sample movement but impedes larval development and tissue regrowth and is therefore not amenable to long-term imaging of wound healing. To overcome this challenge, we engineered a functionally compartmentalized device, the zebrafish Wounding and Entrapment Device for Growth and Imaging (zWEDGI), to orient larvae for high-resolution microscopy, including confocal and second harmonic generation (SHG), while allowing unrestrained tail development and regrowth. In this device, larval viability was maintained and tail regrowth was improved over embedding in agarose. The quality of tail fiber SHG images collected from larvae in the device was similar to fixed samples but provided the benefit of time lapse data collection. Furthermore, we show that this device was amenable to long-term (>24 h) confocal microscopy of the caudal fin. Finally, the zWEDGI was designed and fabricated using readily available techniques so that it can be easily modified for diverse experimental imaging protocols.

The effects of high perioperative inspiratory oxygen fraction for adult surgical patients

BACKGROUND

Available evidence on the effects of a high fraction of inspired oxygen (FIO2) of 60% to 90% compared with a routine fraction of inspired oxygen of 30% to 40%, during anaesthesia and surgery, on mortality and surgical site infection has been inconclusive. Previous trials and meta-analyses have led to different conclusions on whether a high fraction of supplemental inspired oxygen during anaesthesia may decrease or increase mortality and surgical site infections in surgical patients.

OBJECTIVES

To assess the benefits and harms of an FIO2 equal to or greater than 60% compared with a control FIO2 at or below 40% in the perioperative setting in terms of mortality, surgical site infection, respiratory insufficiency, serious adverse events and length of stay during the index admission for adult surgical patients.We looked at various outcomes, conducted subgroup and sensitivity analyses, examined the role of bias and applied trial sequential analysis (TSA) to examine the level of evidence supporting or refuting a high FIO2 during surgery, anaesthesia and recovery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, BIOSIS, International Web of Science, the Latin American and Caribbean Health Science Information Database (LILACS), advanced Google and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) up to February 2014. We checked the references of included trials and reviews for unidentified relevant trials and reran the searches in March 2015. We will consider two studies of interest when we update the review.

SELECTION CRITERIA

We included randomized clinical trials that compared a high fraction of inspired oxygen with a routine fraction of inspired oxygen during anaesthesia, surgery and recovery in individuals 18 years of age or older.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data independently. We conducted random-effects and fixed-effect meta-analyses, and for dichotomous outcomes, we calculated risk ratios (RRs). We used published data and data obtained by contacting trial authors.To minimize the risk of systematic error, we assessed the risk of bias of the included trials. To reduce the risk of random errors caused by sparse data and repetitive updating of cumulative meta-analyses, we applied trial sequential analyses. We used Grades of Recommendation, Assessment, Development and Evaluation (GRADE) to assess the quality of the evidence.

MAIN RESULTS

We included 28 randomized clinical trials (9330 participants); in the 21 trials reporting relevant outcomes for this review, 7597 participants were randomly assigned to a high fraction of inspired oxygen versus a routine fraction of inspired oxygen.In trials with an overall low risk of bias, a high fraction of inspired oxygen compared with a routine fraction of inspired oxygen was not associated with all-cause mortality (random-effects model: RR 1.12, 95% confidence interval (CI) 0.93 to 1.36; GRADE: low quality) within the longest follow-up and within 30 days of follow-up (Peto odds ratio (OR) 0.99, 95% CI 0.61 to 1.60; GRADE: low quality). In a trial sequential analysis, the required information size was not reached and the analysis could not refute a 20% increase in mortality. Similarly, when all trials were included, a high fraction of inspired oxygen was not associated with all-cause mortality to the longest follow-up (RR 1.07, 95% CI 0.87 to 1.33) or within 30 days of follow-up (Peto OR 0.83, 95% CI 0.54 to 1.29), both of very low quality according to GRADE. Neither was a high fraction of inspired oxygen associated with the risk of surgical site infection in trials with low risk of bias (RR 0.86, 95% CI 0.63 to 1.17; GRADE: low quality) or in all trials (RR 0.87, 95% CI 0.71 to 1.07; GRADE: low quality). A high fraction of inspired oxygen was not associated with respiratory insufficiency (RR 1.25, 95% CI 0.79 to 1.99), serious adverse events (RR 0.96, 95% CI 0.65 to 1.43) or length of stay (mean difference -0.06 days, 95% CI -0.44 to 0.32 days).In subgroup analyses of nine trials using preoperative antibiotics, a high fraction of inspired oxygen was associated with a decrease in surgical site infections (RR 0.76, 95% CI 0.60 to 0.97; GRADE: very low quality); a similar effect was noted in the five trials adequately blinded for the outcome assessment (RR 0.79, 95% CI 0.66 to 0.96; GRADE: very low quality). We did not observe an effect of a high fraction of inspired oxygen on surgical site infections in any other subgroup analyses.

AUTHORS' CONCLUSIONS

As the risk of adverse events, including mortality, may be increased by a fraction of inspired oxygen of 60% or higher, and as robust evidence is lacking for a beneficial effect of a fraction of inspired oxygen of 60% or higher on surgical site infection, our overall results suggest that evidence is insufficient to support the routine use of a high fraction of inspired oxygen during anaesthesia and surgery. Given the risk of attrition and outcome reporting bias, as well as other weaknesses in the available evidence, further randomized clinical trials with low risk of bias in all bias domains, including a large sample size and long-term follow-up, are warranted.

Risk Factors Associated With Surgical Site Infection After Pediatric Posterior Spinal Fusion Procedure

Objective.

To identify risk factors associated with surgical site infection (SSI) after pediatric posterior spinal fusion procedure by examining characteristics related to the patient, the surgical procedure, and tissue hypoxia.

Design.

Retrospective case-control study nested in a hospital cohort study.

Setting.

A 475-bed, tertiary care children's hospital.

Methods.

All patients who underwent a spinal fusion procedure during the period from January 1995 through December 2006 were included. SSI cases were identified by means of prospective surveillance using National Nosocomial Infection Surveillance system definitions. Forty-four case patients who underwent a posterior spinal fusion procedure and developed an SSI were identified and evaluated. Each case patient was matched (on the basis of date of surgery, ± 3 months) to 3 control patients who underwent a posterior spinal fusion procedure but did not develop an SSI. Risk factors for SSI were evaluated by univariate analysis and multivariable conditional logistic regression. Odds ratios (ORs), with 95% confidence intervals (CIs) andPvalues, were calculated.

Results.

From 1995 to 2006, the mean annual rate of SSI after posterior spinal fusion procedure was 4.4% (range, 1.1%—6.7%). Significant risk factors associated with SSI in the univariate analysis included the following: a body mass index (BMI) greater than the 95th percentile (OR, 3.5 [95% CI, 1.5–8.3]); antibiotic prophylaxis with clindamycin, compared with other antibiotics (OR, 3.5 [95% CI, 1.2 10.0]); inappropriately low dose of antibiotic (OR, 2.6 [95% CI, 1.0–6.6]); and a longer duration of hypothermia (ie, a core body temperature of less than 35.5°C) during surgery (OR, 0.4 [95% CI, 0.2–0.9]). An American Society of Anesthesiologists (ASA) score of greater than 2, obesity (ie, a BMI greater than the 95th percentile), antibiotic prophylaxis with clindamycin, and hypothermia were statistically significant in the multivariable model.

Conclusion.

An ASA score greater than 2, obesity, and antibiotic prophylaxis with clindamycin were independent risk factors for SSI. Hypothermia during surgery appears to provide protection against SSI in this patient population.

Application of normobaric hyperoxygenation to an ischemic flap and a composite skin graft

Supplemental Digital Content is available in the text.

Background:

Hyperbaric oxygenation has been used for various purposes, but its clinical application is limited due to its pulmonary toxicity. We evaluated the therapeutic value of normobaric hyperoxygenation (NBO) for vascularized and nonvascularized tissue transplantation.

Methods:

Tissue oxygen partial pressure (PtO₂) was measured for various organs in mice under inspiratory oxygen of 20%, 60%, or 100%. A rectangular skin flap (1 × 4 cm) or a composite skin graft (2 × 2 cm) was made on the back of mice, which were housed under 20% or 60% oxygen for the first 3 days after surgery. Cell survival was also examined in organ culture skin samples.

Results:

PtO₂ varied among tissues/organs, but increased depending on inspiratory oxygen concentration in all tissues/organs. Although NBO with 100% O₂ was toxic, NBO with 60% O₂ was safe even when used continuously for a long period. NBO did not significantly improve survival of the rectangular skin flap. On the other hand, in the composite skin graft model, the engraftment area increased significantly (52 ± 10 at 20% vs 68 ± 5.1 at 60%) and contraction decreased significantly (42 ± 8.0 at 20% vs 27 ± 5.7 at 60%). Organ culture of a composite skin sample showed significant cell death under lower oxygen concentrations, supporting the data in vivo.

Conclusions:

The composite graft was maintained until revascularization by plasmatic diffusion from surrounding tissues, in which PtO₂ was improved by NBO. NBO may be an effective adjunct therapy that can be performed readily after nonvascularized tissue grafting.

Role of tumor necrosis factor-alpha in wound repair in human vocal fold fibroblasts

OBJECTIVES/HYPOTHESIS

Tumor necrosis factor-alpha (TNF-alpha) is an inflammatory cytokine and apoptotic molecule that appears to be a mediator in inflammation and fibrosis. The objective of this investigation was to examine the effects of TNF-alpha on 3D Carbylan-GSX in vitro cultured human vocal fold fibroblasts (hVFFs), to provide insight into the mechanism responsible for the improved vocal fold wound healing that has been previous reported with Carbylan-GSX treatment.

STUDY DESIGN

In vitro cell culture.

METHODS

hVFF were cultured in 3D Carbylan-GSX and on polystyrene with different dosages of TNF-alpha (0, 0.1, 1, 10, and 100 ng/mL) with and without 10% fetal bovine serum (FBS). hVFF response to TNF-alpha was characterized by morphology, proliferation rates, and gene transcript levels for matrix metalloproteinase 1 (MMP1), matrix metalloproteinase 2 (MMP2), tissue inhibitor of metalloproteinase 3 (TIMP3), collagen I, collagen III, fibronectin, and TNF-alpha receptor.

RESULTS

In 3D Carbylan-GSX, TNF-alpha inhibited hVFF proliferation in a dose-dependent manner. TNF-alpha (0.1-100 ng/mL) was shown to significantly downregulate TIMP3 and extracellular matrix-related mRNA transcript levels for collagen III and fibronectin and to upregulate MMP1 and MMP2 expression, resulting in increased MMP/TIMP3 ratios. TNF-alpha receptor expression was significantly upregulated in Carbylan-GSX compared to control polystyrene. Responses were more marked in 10% FBS culture.

CONCLUSIONS

After vocal fold injury, locally injected Carbylan-GSX can enhance the role of TNF-alpha in remodeling the lamina propria layer of the vocal fold, accelerating wound healing. Carbylan-GSX has potential as a new therapeutic approach that may lead to better treatment of vocal fold wound healing.

Quantitative dermal measurements following treatment with AirGent

BACKGROUND

As an alternative to other minimally-invasive approaches to facial rejuvenation, enhancement and treatment of the dermis with a compressed air molecule of hyaluronic acid (HA) is a promising method in that it lacks some of the drawbacks of other procedures. The novelty of these systems, one of which is tested in this study, is based on the supposition that jet lateral dispersion of HA produces both instant dermal augmentation and specific wound-healing processes, leading to its long-term dermal thickening.

OBJECTIVES

The authors report on the efficacy and safety of the AirGent system (PerfAction, Rehovot, Israel), which is a renewal system designed to initiate a wound-healing process in the dermal layer. It is a computer-guided system that delivers treatment through compressed air molecules of HA to the dermal layer of the skin.

METHODS

The authors treated 20 patients (a total of 105 treatment sessions) with the AirGent system between May 2008 and November 2008. Each patient received three treatments at three- to four-week intervals. Each patient's skin thickness was measured with ultrasonography pretreatment, immediately after each session, and at six months posttreatment.

RESULTS

Seven days after the last procedure, an increase in skin thickness was observed in all patients. The most significant differences were noted in the upper lip area, where the thickness had increased by an average of 1.3 mm. Six months after the last session, an increase in skin thickness was still noted in most patients, at which time the biggest difference was noted around the eyes, where the skin remained thicker by an average of 0.77 mm over baseline. According to the results of the Global Improvement Assessment questionnaire, at the six-month follow-up to evaluate their satisfaction with the long-term results, at least 59.9% of patients still noted at least a slight improvement in their appearance.

CONCLUSIONS

Although a small group of patients and a relatively short period of observation limit the scope of our conclusions, the data show that the AirGent system is efficacious in producing increases in skin thickness that correlate with at least a substantial or slight improvement of appearance, as reported by the patients themselves.

Prophylaxis and management of wound infections after elective colorectal surgery: a survey of the American Society of Colon and Rectal Surgeons membership

BACKGROUND

Postoperative wound infections are a widespread and costly problem, especially in colorectal surgery. Despite their prevalence, there are few data regarding appropriate management and prevention strategies.

MATERIALS AND METHODS

In order to assess current attitudes and practices about this subject, and as a guide to designing a randomized trial to gather evidence in order to support data-driven protocol development, an e-mail survey was sent to the membership of the American Society of Colorectal Surgeons to assess current attitudes and practices pertaining to prevention and management of wound infections.

RESULTS

Most respondents estimated that the wound infection rate in their own patients was much lower than commonly reported in the literature. Use of evidence-based perioperative strategies for reducing wound infection, such as the use of a wound protector, hyperoxygenation, and implementation of the Surgical Care Improvement Project guidelines, were far from universal. Management strategies varied widely, without apparent rational basis.

CONCLUSION

Based on the practices and beliefs in the surgical community, it is our hope that a multi-institutional study can be carried out to objectify best practices in both the effective and cost-effective management of this common condition and to reduce the wide variation in the treatment of surgical site infections.

About strawberry, crab claws, and the Sir James Black's invention. Hypothesis: can we battle keloids with propranolol?

The cutaneous hemangiomas of infancy or infantile hemangiomas are the most common benign tumor of childhood. They were formerly known as strawberry hemangiomas in reason of its typical appearance although uncommon morphologic variations can be found. Usually hemangiomas are harmless growths that are the result of proliferation of endothelial cells during early childhood. Involution of the lesion occurs at 12-18 months and can last up to 7 years. Occasionally, infantile hemangiomas suffer dramatic overgrowth causing esthetical damages, as well compromises to vital structures that requires prompt intervention. Propranolol, a beta-adrenergic receptor antagonist that was invented by Sir James Black in 1960s, appears to be an effective treatment for infantile hemangiomas and should now be used as a first-line treatment in hemangiomas when intervention is required. Keloids (that resembles crab claws) and hypertrophic scars are fibrous tissue outgrowths that result from a derailment in the normal wound-healing process. Systemic or intralesional propranolol may play a role in the amelioration of keloids and hypertrophic scars due to their potential to induce vasoconstriction of over proliferating tissues, triggering apoptosis of endothelial cells and also to their effect as modulator of inflammatory process during wound healing. In adding the propranolol to the melting pot of abnormal (or supra-normal) wound healing, we hypothesized that we can battle keloids with propranolol.

Ventilatory management during routine general anaesthesia

Intraoperative hypoxaemia and postoperative respiratory complications remain the challenges of modern anaesthetic practice. Anaesthesia causes both depression of respiratory centres and profound changes of respiratory mechanics. Most anaesthetized patients consequently require mechanical ventilation and supplemental oxygen. Recent data suggest that intraoperative respiratory management of a patient can affect postoperative outcome. In this review, we briefly describe the mechanisms responsible for the impairment of intraoperative gas exchange and provide guidelines to prevent or manage hypoxaemia. Moreover, we discuss several aspects of mechanical ventilation that can be employed to improve patients' outcome.

Wound healing essentials: let there be oxygen

The state of wound oxygenation is a key determinant of healing outcomes. From a diagnostic standpoint, measurements of wound oxygenation are commonly used to guide treatment planning such as amputation decision. In preventive applications, optimizing wound perfusion and providing supplemental O(2) in the perioperative period reduces the incidence of postoperative infections. Correction of wound pO(2) may, by itself, trigger some healing responses. Importantly, approaches to correct wound pO(2) favorably influence outcomes of other therapies such as responsiveness to growth factors and acceptance of grafts. Chronic ischemic wounds are essentially hypoxic. Primarily based on the tumor literature, hypoxia is generally viewed as being angiogenic. This is true with the condition that hypoxia be acute and mild to modest in magnitude. Extreme near-anoxic hypoxia, as commonly noted in problem wounds, is not compatible with tissue repair. Adequate wound tissue oxygenation is required but may not be sufficient to favorably influence healing outcomes. Success in wound care may be improved by a personalized health care approach. The key lies in our ability to specifically identify the key limitations of a given wound and in developing a multifaceted strategy to specifically address those limitations. In considering approaches to oxygenate the wound tissue it is important to recognize that both too little as well as too much may impede the healing process. Oxygen dosing based on the specific need of a wound therefore seems prudent. Therapeutic approaches targeting the oxygen sensing and redox signaling pathways are promising.

Pseudomonas aeruginosa PAO1 pyocin production affects population dynamics within mixed-culture biofilms

Transcriptomic and phenotypic studies showed that pyocins are produced in Pseudomonas aeruginosa PAO1 aerobic and anaerobic biofilms. Pyocin activity was found to be high in slow-growing anaerobic biofilms but transient in aerobic biofilms. Biofilm coculture of strain PAO1 and a pyocin-sensitive isolate showed that pyocin production had a significant impact on bacterial population dynamics, particularly under anaerobic conditions.

Postpregnancy genital tract and wound infections

Despite the widespread application of standard aseptic techniques during vaginal birth, cesarean birth, and/or termination of pregnancy, postpregnancy infections remain a significant source of maternal morbidity and mortality. Obstetric infection accounts for more than 12% of maternal deaths. Infection occurs most frequently in women who have cesarean births, and following spontaneous or elective termination of pregnancy. Infection is estimated to be the second highest cause of under-reported maternal death in the United States. This article identifies measures to aid in primary prevention and recognition of obstetric infections in order to facilitate early diagnosis and treatment.

Changes in optical properties of tissue during acute wound healing in an animal model

Changes of optical properties of wound tissue in hairless rats were quantified by diffuse photon density wave methodology at near-infrared frequencies. The diffusion equation for semi-infinite media was used to calculate the absorption and scattering coefficients based on measurements of phase and amplitude with a frequency domain device. There was an increase in the absorption and scattering coefficients and a decrease in blood saturation of the wounds compared with the nonwounded sites. The changes correlated with the healing stage of the wound. The data obtained were supported by immunohistochemical analysis of wound tissue. These results verified now by two independent animal studies could suggest a noninvasive method to detect the progress of wound healing.

Wound bed preparation and oxygen balance--a new component?

Chronic wounds have traditionally been treated by conservative means. It was Winter's moist wound healing research, in 1962, that stimulated a proliferation of a moist interactive dressing technologies. Even considering this advancement in thinking, chronic wounds continue to be a problem for many clinicians. An increasing delineation of the science of healing in the past 20 years has redefined the way in which we both evaluate and treat wounds. This scientific understanding has raised wound care from the clinical problem arena to that of clinical specialty, where many now cross refer patients to specialists in this field. Wound bed preparation (WBP) has played a significant role in this change in practice. The concept has changed an 'art' of switching at random from one dressing to another, into a clinical science. WBP has come to the forefront as a major educational aid to help others develop appropriate treatment of the underlying disease causing the wound and patient requirements. The concept of WBP evolved over the recent years, becoming more and more sophisticated with time. Recent adaptations have brought together many of the current components. This article proposes yet another element of WBP, that of 'oxygen balance'.

The therapeutic use of honey

Honey has been shown to have antibacterial activity against a variety of species of bacteria in vitro. Although the evidence regarding the use of honey for wound treatment in neonates and infants is interesting, it is not strong. The sample sizes in the cited clinical studies are small; there were no comparison groups and no randomization. It appears that honey may be safe and useful in treating difficult-to-heal infected wounds, but double-blinded randomized controlled clinical trials with sufficient power are needed to determine the efficacy of honey in both initial wound management and secondary treatment of infected and poorly healing wounds. A comparison of different types of honey would be an important component of these trials. Currently, there is not enough evidence to recommend one type of honey over another type; however, honey and wound care experts do recommend honey for wound care, not for consumption.

Postcare Recommendations for Emergency Department Wounds

Diligent posttreatment wound care management undoubtedly will improve wound outcome and patient satisfaction. There are limited recommendations in the literature to guide management plans. Nevertheless patients must receive specific instructions to complete wound care. These instructions should include whether a dressing is indicated, which dressing should be used, the duration of use, and the method of application. The plan must explain clearly the reasons for returning for further medical attention, for follow-up, for routine removal of sutures/staples, and an earlier return for possible concerns of infection or dehiscence. Preprinted discharge instruction sheets are useful, and illustrations can be helpful.