A novel real-time model for predicting acute kidney injury in critically ill patients within 12 hours.

BACKGROUND: A major challenge in prevention and early treatment of acute kidney injury (AKI) is the lack of high-performance predictors in critically ill patients. Therefore, we innovatively constructed U-AKIpredTM for predicting AKI in critically ill patients within 12 h of panel measurement. METHODS: The prospective cohort study included 680 patients in the training set and 249 patients in the validation set. After performing inclusion and exclusion criteria, 417 patients were enrolled in the training set and 164 patients were enrolled in the validation set finally. AKI was diagnosed by Kidney Disease Improving Global Outcomes (KDIGO) criteria. RESULTS: Twelve urinary kidney injury biomarkers (mALB, IgG, TRF, α1MG, NAG, NGAL, KIM-1, L-FABP, TIMP2, IGFBP7, CAF22 and IL-18) exhibited good predictive performance for AKI within 12 h in critically ill patients. U-AKIpredTM, combined with three crucial biomarkers (α1MG, L-FABP and IGFBP7) by multivariate logistic regression analysis, exhibited better predictive performance for AKI in critically ill patients within 12 h than the other twelve kidney injury biomarkers. The area under the curve (AUC) of the U-AKIpredTM, as a predictor of AKI within 12 h, was 0.802 (95% CI: 0.771-0.833, P < 0.001) in the training set and 0.844 (95% CI: 0.792-0.896, P < 0.001) in validation cohort. A nomogram based on the results of the training and validation sets of U-AKIpredTM was developed which showed optimal predictive performance for AKI. The fitting effect and prediction accuracy of U-AKIpredTM was evaluated by multiple statistical indicators. To provide a more flexible predictive tool, the dynamic nomogram (https://www.xsmartanalysis.com/model/U-AKIpredTM) was constructed using a web-calculator. Decision curve analysis (DCA) and a clinical impact curve were used to reveal that U-AKIpredTM with the three crucial biomarkers had a higher net benefit than these twelve kidney injury biomarkers respectively. The net reclassification index (NRI) and integrated discrimination index (IDI) were used to improve the significant risk reclassification of AKI compared with the 12 kidney injury biomarkers. The predictive efficiency of U-AKIpredTM was better than the NephroCheck® when testing for AKI and severe AKI. CONCLUSION: U-AKIpredTM is an excellent predictive model of AKI in critically ill patients within 12 h and would assist clinicians in identifying those at high risk of AKI.

Efficacy and Safety of PL-5 (Peceleganan) Spray for Wound Infections: A Phase IIb Randomized Clinical Trial.

OBJECTIVE: To assess the safety and efficacy of antimicrobial peptide PL-5 (Peceleganan) spray in the treatment of wound infections. BACKGROUND: Antimicrobial peptide PL-5 spray is a novel topical antimicrobial agent. METHODS: We conducted a multicenter, open-label, randomized, controlled phase IIb clinical trial to evaluate the efficacy and safety of PL-5 spray, as compared with silver sulfadiazine, in patients with skin wound infections. The primary efficacy outcome was the clinical efficacy rate on the first day after ending the treatment (D8). The secondary efficacy outcome was the clinical efficacy rate on the fifth day posttreatment (D5), the bacteria clearance rate, and the overall efficacy rate at the mentioned 2 time points. The safety outcomes included adverse reactions and pharmacokinetic analysis posttreatment. RESULTS: A total of 220 patients from 27 hospitals in China were randomly assigned to 4 groups. On D8, the efficacy rate was 100.0%, 96.7%, 96.7% for the 1‰ PL-5, 2‰ PL-5, 4‰ PL-5 groups, respectively, as compared with 87.5% for the control group. The efficacy rate among the 4 groups was significantly different ( P <0.05). On D5, the efficacy rate was 100.0%, 93.4%, 98.3% for the 1‰ PL-5, 2‰ PL-5, 4‰ PL-5 groups, respectively, as compared with 82.5% for the control group. The efficacy rate among the 4 groups was significantly different ( P <0.05). The blood concentration of PL-5 was not detectable in pharmacokinetic analysis. No severe adverse event related to the application of PL-5 was reported. CONCLUSIONS: Antimicrobial peptide PL-5 spray is safe and effective for the treatment of skin wound infections. TRIAL REGISTRATION: ChiCTR2000033334.

Principles of extramural health care for chronic wounds in China.

Development of extramural health care for chronic wounds is still in its infancy in China, and thus it is urgent and vital to establish a correct concept and practicable principles. The authors reviewed recent domestic and international literature and summarized the following treatment procedures and principles for extramural health care of chronic wounds. (1) The patient needs to do self-assessment of the wound by using available simple methods; (2) The patient consults with professional physicians or nurses on wound care to define the severity and etiology of the non-healing wound; (3) Professionals evaluate the existing treatment strategies; (4) Etiological treatments are given by professionals; (5) Patients buy needed dressings via the more convenient ways from pharmacies, e-commerce platform or others; (6) Professionals provide a standardized and reasonable therapeutic plan based on the patient's wound conditions; (7) Both professionals and the patient pay attention to complications to prevent adverse outcomes; (8) Professionals strengthen the public education on wound care and integrated rehabilitation. This review expected to provide new perspectives on the therapeutic strategies for chronic wounds in an extramural setting.

Advances in surgical treatment of hidradenitis suppurative. / åŒ–è„“æ€§æ±—è ºç‚Žå¤–ç§‘æ²»ç–—ç ”ç©¶è¿›å±•.

Hidradenitis suppurative is a chronic, refractory and recurrent dermatological disease. The disease should be managed by targeted surgical intervention on the basis of medical treatment. Currently, the surgical treatment methods include local treatments like incision and drainage, unroofing, laser therapy, intense pulsed light therapy, photodynamic therapy, as well as complete lesion resection such as skin-tissue saving excision with electrosurgical peeling and extended excision. The clearance range, therapeutic effect, postoperative complications, and recurrence risk vary among the different treatment methods. Local treatments cause less damage, but have high recurrence rates, and are mainly for mild to moderate hidradenitis suppurative patients. Complete lesion resections have relatively low recurrence rates, but may bring more surgical injuries, and postoperative reconstructions are needed, which are mainly for moderate to severe hidradenitis suppurative patients. In this article, the surgical treatment principles and various surgical treatment methods of hidradenitis suppurative are reviewed, to provide a reference for the diagnosis and treatment of this disease in clinical practice.

Use of the Braden Scale to Predict Injury Severity in Mass Burn Casualties.

BACKGROUND Mass burn casualties impose an enormous burden on triage systems. The triage capacity of the Braden Scale for detecting injury severity has not been evaluated in mass burn casualties. MATERIAL AND METHODS The New Injury Severity Score (NISS) was used to dichotomize the injury severity of patients. The Braden Scale and other potentially indicative measurement tools were evaluated using univariate analysis and multivariate logistic regression. The relationships between the Braden Scale and other continuous variables with injury severity were further explored by correlation analysis and fitted with regression models. Receiver operating characteristic (ROC) curve analysis was used to validate triage capacity and compare prognostic accuracy. RESULTS A total of 160 hospitalized patients were included in our study; 37 were severely injured, and 123 were not. Injury severity was independently associated with the Numerical Rating Scale (adjusted OR, 1.816; 95% CI, 1.035-3.187) and Braden Scale (adjusted OR, 0.693; 95% CI, 0.564-0.851). The ROC curve of the fitted quadratic model of the Braden Scale was 0.896 (0.840-0.953), and the cut-off value was 17. The sensitivity was 81.08% (64.29-91.44%) and the specificity was 82.93% (74.85-88.89%). Comparison of ROC curves demonstrated an infinitesimal difference between the Braden Scale and NISS for predicting 30-day hospital discharge (Z=0.291, P=0.771) and Intensive Care Unit admission (Z=2.016, P=0.044). CONCLUSIONS The Braden Scale is a suitable triage tool for predicting injury severity and forecasting disability-related outcomes in patients affected by mass burn casualty incidents.

Regeneration of skin appendages and nerves: current status and further challenges.

Tissue-engineered skin (TES), as an analogue of native skin, is promising for wound repair and regeneration. However, a major drawback of TES products is a lack of skin appendages and nerves to enhance skin healing, structural integrity and skin vitality. Skin appendages and nerves are important constituents for fully functional skin. To date, many studies have yielded remarkable results in the field of skin appendages reconstruction and nerve regeneration. However, patients often complain about a loss of skin sensation and even cutaneous chronic pain. Restoration of pain, temperature, and touch perceptions should now be a major challenge to solve in order to improve patients' quality of life. Current strategies to create skin appendages and sensory nerve regeneration are mainly based on different types of seeding cells, scaffold materials, bioactive factors and involved signaling pathways. This article provides a comprehensive overview of different strategies for, and advances in, skin appendages and sensory nerve regeneration, which is an important issue in the field of tissue engineering and regenerative medicine.

Epidemiological characteristics and clinical analyses of chronic cutaneous wounds of inpatients in China: Prevention and control.

The increased incidence of chronic cutaneous wounds is likely to lead to increased mortality, and therefore, deserves greater attention. More insight is needed into the magnitude of the problem of chronic cutaneous wounds and methods for their prevention and treatment in China. A retrospective analysis of data retrieved from an electronic health-records database on 3300 patients with chronic skin wounds was conducted from 1 January 2018 to 31 December 2018. The patients had been admitted to the medical and surgical wards of 17 third-grade class-A hospitals in China. The study's aim was to compare the characteristics (eg, demographic and clinical) associated with different causes and distributions of patients' chronic wounds. Among the 3300 patients, 66.03% were males and 33.97% were females. The mean age was 57 years and the increasing prevalence of chronic skin wounds with aging was quite high. The primary causes of chronic wounds were diabetes or infection, followed by pressure ulcers, trauma, and iatrogenic wounds. The distribution of skin wounds was mainly in the lower extremities (56.1%), followed by the trunk (18.6%). The mean duration of hospital stay was 29 days and the mean recurrence was 3 months. Chronic skin wounds were related to occupation, educational level, lifestyle habits, and income. The main cause of chronic skin wounds has shifted from trauma to chronic disease. Normalization checks, bacterial cultures, and antibiotic use in China need to be standardized and the training of wound specialists should be further strengthened. The association of aging and wound infection was significant. Preventive management and efficient treatment should correspond to the needs of the different regions of China. These results may serve as a reference for other developing countries in their transitional development.

Non-viral gene delivery systems for tissue repair and regeneration.

Critical tissue defects frequently result from trauma, burns, chronic wounds and/or surgery. The ideal treatment for such tissue loss is autografting, but donor sites are often limited. Tissue engineering (TE) is an inspiring alternative for tissue repair and regeneration (TRR). One of the current state-of-the-art methods for TRR is gene therapy. Non-viral gene delivery systems (nVGDS) have great potential for TE and have several advantages over viral delivery including lower immunogenicity and toxicity, better cell specificity, better modifiability, and higher productivity. However, there is no ideal nVGDS for TRR, hence, there is widespread research to improve their properties. This review introduces the basic principles and key aspects of commonly-used nVGDSs. We focus on recent advances in their applications, current challenges, and future directions.

Improved Dermal Regeneration Using a Combination of Dermal Substitutes and Dermal Fibroblast Optimization: A Hypothesis.

In human adults, the repair of cutaneous wounds usually leads to scar formation rather than regeneration. Dermal substitutes have been used as a regenerative template for reducing scar formation and improving the extent of dermal regeneration. However, achievement of complete regeneration is still a long way off. Dermal substitutes are characterized by unusual regenerative activity, appearing to function by acting as temporary configurational guides for cell infiltration and synthesis of new stroma. Fibroblasts are important cells with many vital functions in wound-healing processes. They are heterogeneous with distinct characteristics according to their source location, such as subcutaneous tissue, superficial-layer dermis, and deep-layer dermis. Many studies have shown that superficial dermal fibroblasts possess the potential to form dermis-like tissue. Fibroblasts in deep-layer dermis and subcutaneous tissue may play a critical role in the formation of hypertrophic scars. Fibroblast phenotype affects the newly formed dermal architecture and influences the dermal regeneration effect induced by dermal substitutes. It is hypothesized that better regeneration of the dermis can be achieved using dermal substitutes along with dermal fibroblast optimization.

Effects of hydrogen-rich saline on early acute kidney injury in severely burned rats by suppressing oxidative stress induced apoptosis and inflammation.

BACKGROUND: Early acute kidney injury (AKI) in severely burned patients predicts a high mortality that is multi-factorial. Hydrogen has been reported to alleviate organ injury via selective quenching of reactive oxygen species. This study investigated the potential protective effects of hydrogen against severe burn-induced early AKI in rats. METHODS: Severe burn were induced via immersing the shaved back of rats into a 100°C bath for 15 s. Fifty-six Sprague-Dawley rats were randomly divided into Sham, Burn + saline, and Burn + hydrogen-rich saline (HS) groups, and renal function and the apoptotic index were measured. Kidney histopathology and immunofluorescence staining, quantitative real-time PCR, ELISA and western blotting were performed on the sera or renal tissues of burned rats to explore the underlying effects and mechanisms at varying time points post burn. RESULTS: Renal function and tubular apoptosis were improved by HS treatment. In addition, the oxidation-reduction potential and malondialdehyde levels were markedly reduced with HS treatment, whereas endogenous antioxidant enzyme activities were significantly increased. HS also decreased the myeloperoxidase levels and influenced the release of inflammatory mediators in the sera and renal tissues of the burned rats. The regulatory effects of HS included the inhibition of p38, JNK, ERK and NF-κB activation, and an increase in Akt phosphorylation. CONCLUSION: Hydrogen can attenuate severe burn-induced early AKI; the mechanisms of protection include the inhibition of oxidative stress induced apoptosis and inflammation, which may be mediated by regulation of the MAPKs, Akt and NF-κB signalling pathways.

AGEs and chronic subclinical inflammation in diabetes: disorders of immune system.

Chronic subclinical inflammation represents a risk factor of type 2 diabetes and several diabetes complications, including neuropathy and atherosclerosis including macro-vasculopathy and micro-vasculopathy. However, the inflammatory response in the diabetic wound was shown to be remarkably hypocellular, unregulated and ineffective. Advanced glycation end products (AGEs) and one of its receptors, RAGE, were involved in inducing chronic immune imbalance in diabetic patients. Such interactions attracts immune cell into diffused glycated tissue and activates these cells to induce inflammatory damage, but disturbs the normal immune rhythm in diabetic wound. Traditional measurements of AGEs are high-performance liquid chromatography and immunohistochemistry staining, but their application faces the limitations including complexity, cost and lack of reproducibility. A new noninvasive method emerged in 2004, using skin autofluorescence as indicator for AGEs accumulation. It had been reported to be informative in evaluating the chronic risk of diabetic patients. Studies have indicated therapeutic potentials of anti-AGE recipes. These recipes can reduce AGE absorption/de novo formation, block AGE-RAGE interaction and arrest downstream signaling after RAGE activation.

The characteristics and correlation between the ischemia-reperfusion and changes of redox status in the early stage of severe burns.

OBJECTIVE: Both the ischemia-reperfusion injury and the abnormal changes of redox status are the important pathologic changes in the burn shock stage for severe burns. The study of clinical dynamic, quantitative relevance about them was performed. METHODS: In this study, blood redox potential (ORP) values (ΔORP value was adopted, as the quantitative index to reflect the overall redox status), plasma uric acid levels (important antioxidant, as antioxidant index), and the burn shock state-related indicators (lactic acid and hematocrit) of 48 burn patients were dynamically, quantitatively monitored during the early stage after injury. RESULTS: The results revealed that the duration of abnormal fluctuation of redox status in the early stage of severe burns was longer than that of the traditional clinical shock stage (2-3 days). The changes of overreduction soon after injury were closely related to the hypovolemia-related hypoxia, and the following overoxidation status was consistent with the pathophysiological changes related to the reperfusion, and the degrees of variation were closely related to the severity of burn injury and prognosis. Moreover, early surgery (3 days after injury) had no significant influence on the changing trend of abnormal redox status in the early stage of severe burns. CONCLUSION: The ischemia-reperfusion injury caused by burn shock appears the main factor contributing to the abnormal biphasic changes of redox status in the early stage of severe burns. Our findings provide useful information for the redox regulation treatment for burn shock.

Astaxanthin attenuates early acute kidney injury following severe burns in rats by ameliorating oxidative stress and mitochondrial-related apoptosis.

Early acute kidney injury (AKI) is a devastating complication in critical burn patients, and it is associated with severe morbidity and mortality. The mechanism of AKI is multifactorial. Astaxanthin (ATX) is a natural compound that is widely distributed in marine organisms; it is a strong antioxidant and exhibits other biological effects that have been well studied in various traumatic injuries and diseases. Hence, we attempted to explore the potential protection of ATX against early post burn AKI and its possible mechanisms of action. The classic severe burn rat model was utilized for the histological and biochemical assessments of the therapeutic value and mechanisms of action of ATX. Upon ATX treatment, renal tubular injury and the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were improved. Furthermore, relief of oxidative stress and tubular apoptosis in rat kidneys post burn was also observed. Additionally, ATX administration increased Akt and Bad phosphorylation and further down-regulated the expression of other downstream pro-apoptotic proteins (cytochrome c and caspase-3/9); these effects were reversed by the PI3K inhibitor LY294002. Moreover, the protective effect of ATX presents a dose-dependent enhancement. The data above suggested that ATX protects against early AKI following severe burns in rats, which was attributed to its ability to ameliorate oxidative stress and inhibit apoptosis by modulating the mitochondrial-apoptotic pathway, regarded as the Akt/Bad/Caspases signalling cascade.

Levels of brain natriuretic peptide are associated with peripheral arterial disease in subjects with type-2 diabetes mellitus.

BACKGROUND: The effects of brain natriuretic peptide (BNP) on the risk of cardiovascular disease and atherosclerosis have been studied. However, little information is available regarding peripheral arterial disease (PAD), particularly among subjects with type-2 diabetes mellitus (T2DM). The aim of our study was to assess the potential relationship between BNP levels and PAD among T2DM patients. METHODS: The study cohort was 507 T2DM outpatients in which BNP levels were measured. Cross-sectional associations between BNP levels (in tertiles) and PAD were examined. RESULTS: Compared withT2DM patients without PAD, BNP levels were markedly higher in patients with PAD (p = 0.001). Correlation analyses showed that the BNP level was negatively correlated with the ankle-brachial index (r = -0.453, p = 0.033). At a cutoff value of 78.2 pg/ml, the BNP level showed a sensitivity of 71.9%, a specificity of 68.1%, and a positive predictive value of 84.3% for a diagnosis of PAD. The area under the receiver-operating characteristic curve increased significantly if BNP levels were incorporated into a predictive model of the potential risk factors for PAD (0.85 vs 0.81, p = 0.029). CONCLUSIONS: BNP is a potential and promising biomarker for PAD screening in T2DM patients.

Topical negative pressure improves autograft take by altering nutrient diffusion: A hypothesis.

The one-step surgical procedure for dermal substitutes combined with topical negative pressure (TNP) has proven effective for treating deep skin defects with improved graft take. The primary mechanism by which TNP improves autograft take is unknown. Some studies suggest that TNP promotes the rapid angiogenesis of dermal substitutes, improving graft take. However, at the early stage of one-step transplantation, the vascular system has not formed and imbibition is the main mode of nutrient supply. TNP can shorten the diffusion distance from the wound bed to the graft, leading to the timely renewal of the wound exudate via suction, removing any surplus exudate, and reducing tissue edema. In addition, TNP can regulate the local blood flow and inhibit bacterial colonization. Therefore, we hypothesized that TNP establishes a rapid balance between the nutrient supply to the wound bed and nutritional requirement of the graft via these pathways in the relatively closed, moist environment, improving autograft take. However, this balance could be affected by any negative pressure, intermittent or continuous. It is necessary to test this hypothesis in laboratory and clinical studies of the mode of nutrient supply in the imbibition phase and the change in exudate content.

The asynchronous dynamic changes and interrelationships between leukocyte composition and inflammatory markers and potential clinical significance in the early stage and sepsis stage in severe burns.

OBJECTIVE: The aim of this study is to investigate the dynamic changes and interrelationships between leukocyte components and inflammatory markers in the early stages and sepsis stage in severe burns, and explore their potential clinical significance. METHODS: This is a 5-year retrospective cohort study involving 107 patients with severe burns (the total body surface area of burn (TBSA) > 50%), in which, neutrophil count, lymphocyte count, monocyte count, the ratio of the product of monocyte and lymphocyte count to neutrophil count (MLPN), procalcitonin (PCT), C-reactive protein (CRP), capillary leakage index (CLI) and creatinine (Scr) were investigated. RESULTS: Within one week after injury, the leukocyte components and MLPN showed a V-shaped change, with a peak immediately after injury and a trough on the 4th or 5th day after injury, while CRP showed a continuous upward trend, and the leukocyte compositions of all patients were negatively correlated with CRP values. The counts of leukocytes components and CRP values in deceased patients were higher than those in surviving patients within 2 days after injury. In the resorption stage, although no significant difference in lymphocyte and monocyte counts between surviving and deceased patients was found, the monocyte and lymphocyte counts in deceased patients were lower than those in surviving patients on the 5th to 7th day after injury, while neutrophils counts and CRP values remained higher than those in surviving patients. And the dynamic changes of MLPN were consistent with those of leukocyte compositions and opposite to those of PCT values. Moreover, MLPN were negatively correlated with CRP, CLI, and Scr values in the early stage of severe burns. In sepsis stage, as the condition worsened, the values of CRP, PCT and neutrophil counts continuously increased with varying degree, while lymphocyte and monocyte counts, and MLPN showed continuously decrease, but rebounded to increase before death. And the occurrence of the trough of monocyte counts was earlier than that of lymphocyte counts, a negative correlation between neutrophil counts and PCT values was found. CONCLUSION: The results of this study revealed the dynamic interrelationships between leucocyte components and inflammatory indicators in the early stages and sepsis stage in severe burns, reflecting the different weightings of inflammatory responses and immune dysfunction in different disease stages and its correlation with outcomes, which providing useful clinical information for dynamic immunomodulatory therapy. Moreover, dynamic monitoring of MLPN value can provide timely information for clinical evaluation.

Estimates of resting energy expenditure using predictive equations in adults with severe burns: A systematic review and meta-analysis.

BACKGROUND: Many equations to estimate the resting energy expenditure (REE) of patients with burns are currently available, but which of them provides the best guide to optimize nutrition support is controversial. This review examined the bias and precision of commonly used equations in patients with severe burns. METHODS: A systematic search of the PubMed, Web of Science, Embase, and Cochrane Library databases was undertaken on June 1, 2023, to identify studies comparing predicted REE (using equations) with measured REE (by indirect calorimetry [IC]) in adults with severe burns. Meta-analyses of bias and calculations of precisions were performed in each predictive equation, respectively. RESULTS: Nine eligible studies and 12 eligible equations were included. Among the equations, the Toronto equation had the lowest bias (26.1 kcal/day; 95% CI, -417.0 to 469.2), followed by the Harris-Benedict equation × 1.5 (1.5HB) and the Milner equation. The Ireton-Jones equation (303.4 kcal/day; 95% CI, 224.5-382.3) acceptably overestimated the REE. The accuracy of all of the equations was <50%. The Ireton-Jones equation had the relatively highest precision (41.2%), followed by the 1.5HB equation (37.0%) and the Toronto equation (34.7%). CONCLUSION: For adult patients with severe burns, all of the commonly used equations for the prediction of REE are inaccurate. It is recommended to use IC for accurate REE measurements and to use the Toronto equation, 1.5HB equation, or Ireton-Jones equation as a reference when IC is not available. Further studies are needed to propose more accurate REE predictive models.

Mechanical strategies to promote vascularization for tissue engineering and regenerative medicine.

Vascularization is a major challenge in the field of tissue engineering and regenerative medicine. Mechanical factors have been demonstrated to play a fundamental role in vasculogenesis and angiogenesis and can affect the architecture of the generated vascular network. Through the regulation of mechanical factors in engineered tissues, various mechanical strategies can be used to optimize the preformed vascular network and promote its rapid integration with host vessels. Optimization of the mechanical properties of scaffolds, including controlling scaffold stiffness, increasing surface roughness and anisotropic structure, and designing interconnected, hierarchical pore structures, is beneficial for the in vitro formation of vascular networks and the ingrowth of host blood vessels. The incorporation of hollow channels into scaffolds promotes the formation of patterned vascular networks. Dynamic stretching and perfusion can facilitate the formation and maturation of preformed vascular networks in vitro. Several indirect mechanical strategies provide sustained mechanical stimulation to engineered tissues in vivo, which further promotes the vascularization of implants within the body. Additionally, stiffness gradients, anisotropic substrates and hollow channels in scaffolds, as well as external cyclic stretch, boundary constraints and dynamic flow culture, can effectively regulate the alignment of vascular networks, thereby promoting better integration of prevascularized engineered tissues with host blood vessels. This review summarizes the influence and contribution of both scaffold-based and external stimulus-based mechanical strategies for vascularization in tissue engineering and elucidates the underlying mechanisms involved.

Associated predictors of prolonged length of stay in patients surviving extensive burns: A large multicenter retrospective study.

BACKGROUND: Patients with extensive burns are critically ill and have long treatment periods. Length of stay (LOS) is a good measure for assessing treatment. This study sought to identify predictors of prolonged LOS in patients with extensive burns (≥50% TBSA). METHODS: This retrospective multicenter cohort study included adults aged ≥ 18 years who survived extensive burns in three burn centers in Eastern China between January 2016 and June 2022. Epidemiological, demographic and clinical outcomes data were extracted from electronic medical records and compared between patients with/without prolonged LOS, which was defined as LOS greater than the median. Logistic regression analysis was used to identify predictors of prolonged LOS. RESULTS: The study sample included 321 patients, of whom 156 (48.6%) had an LOS of 58 days (IQR 41.0-77.0). Univariate regression analysis showed that increased total burn area and increased full-thickness burn area; electrical, chemical and other burns; increased erythrocytes, leukocytes, platelets or serum creatinine within 24 h of admission; concomitant inhalation injury, pulmonary edema, sepsis, bloodstream infection, wound infection, pulmonary infection, urinary tract infection, or HB < 70 g/L during hospitalization were associated with prolonged LOS in patients with extensive burns. Increased number of surgical operations, mechanical ventilation and renal replacement therapy were also associated with prolonged LOS (P < 0.05 or P < 0.001). Multivariate regression analysis revealed that increased total burn area (ratio 1.032, 95%CI 1.01-1.055; P = 0.004), electrical and chemical or other burns (3.282, 1.335-8.073; P = 0.01), development of wound infection (2.653 1.285-5.481; P = 0.008) and increased number of operative procedures (1.714, 1.388-2.116, P < 0.001) were significant predictors. CONCLUSIONS: Increased area of full-thickness burn,occurrence of electrical and chemical or other burns,occurrence of wound infection and increased number of surgeries are the best predictors of prolonged LOS in patients with extensive burns. Clarifying relevant predictors of burn patients' LOS provides a reliable reference for clinical treatment.

Ultra-restrictive red blood cell transfusion strategies in extensively burned patients.

In recent years, due to the shortage of blood products, some extensive burn patients were forced to adopt an "ultra-restrictive" transfusion strategy, in which the hemoglobin levels of RBC transfusion thresholds were < 7 g/dl or even < 6 g/dl. This study investigated the prognostic impacts of ultra-restrictive RBC transfusion in extensive burn patients. This retrospective multicenter cohort study recruited extensive burns (total body surface area ≥ 50%) from three hospitals in Eastern China between 1 January 2016 and 30 June 2022. Patients were divided into an ultra-restrictive transfusion group and a restrictive transfusion group depending on whether they received timely RBC transfusion at a hemoglobin level < 7 g/dl. 1:1 ratio propensity score matching (PSM) was performed to balance selection bias. Modified Poisson regression and linear regression were conducted for sensitive analysis. Subsequently, according to whether they received timely RBC transfusion at a hemoglobin level < 6 g/dl, patients in the ultra-restrictive transfusion group were divided into < 6 g/dl group and 6-7 g/dl group to further compare the prognostic outcomes. 271 eligible patients with extensive burns were included, of whom 107 patients were in the ultra-restrictive transfusion group and 164 patients were in the restrictive transfusion group. The ultra-restrictive transfusion group had a significantly lower RBC transfusion volume than the restrictive transfusion group (11.5 [5.5, 21.5] vs 17.3 [9.0, 32.5] units, p = 0.004). There were no significant differences between the two groups in terms of in-hospital mortality, risk of infection, hospital length of stay, and wound healing time after PSM or multivariate adjustment (p > 0.05). Among the ultra-restrictive transfusion group, patients with RBC transfusion threshold < 6 g/dl had a significantly higher hospital mortality than 6-7 g/dl (53.1% vs 21.3%, p = 0.001). For extensive burn patients, no significant adverse effects of ultra-restrictive RBC transfusion were found in this study. When the blood supply is tight, it is acceptable to adopt an RBC transfusion threshold of < 7 g/dL but not < 6 g/dL.