Gauze Group Research Articles

Expansion-clotting chitosan fabrics based on unidirectional fast-absorption fibers for rapid hemorrhage control

The rapid absorption of water from the blood to concentrate erythrocytes and platelets, thus triggering quick closure, is important for hemostasis. Herein, expansion-clotting chitosan fabrics are designed and fabricated by ring spinning of polylactic acid (PLA) filaments as the core layer and highly hydrophilic carboxyethyl chitosan (CECS) fibers as the sheath layer, and subsequent knitting of obtained PLA@CECS core spun yarns. Due to the unidirectional fast-absorption capacity of CECS fibers, the chitosan fabrics can achieve erythrocytes and platelets aggregate quickly by concentrating blood, thus promoting the formation of blood clots. Furthermore, the loop structure of coils formed in the knitted fabric can help them to expand by absorbing water to close their pores, providing effective sealing for bleeding. Besides, They have enough mechanical properties, anti-penetrating ability, and good tissue-adhesion ability in wet conditions, which can form a physical barrier to resist blood pressure during hemostasis and prevent them from falling off the wound, thus enhancing hemostasis synergistically. Therefore, the fabrics exhibit superior hemostatic performance in the rabbit liver, spleen, and femoral artery puncture injury model compared to the gauze group. This chitosan fabric is a promising hemostatic material for hemorrhage control.

Comparison of Polyvinyl Alcohol Sponge and Gauze Packing for Nasal Fracture Treatment: An Efficacy and Safety Analysis.

Nasal fractures are commonly treated using nasal packing as an internal splint after performing closed reduction. Although gauze and polyvinyl alcohol sponge (PVAS) are both commonly used for packing, few reports have compared their efficacy and safety in nasal fracture treatment. Therefore, in this study, the authors, aimed to retrospectively compare the efficacy and safety of gauze packing in 208 patients and PVAS packing in 225 patients who underwent closed reduction at our hospital. The proportions of patients requiring revision surgery did not differ significantly between the PVAS and gauze groups ( P =0.627). However, in comparison to the gauze group, the PVAS group displayed significantly fewer instances of uncontrolled epistaxis following packing removal, as well as fewer occurrences of dropout and loss of packing ( P =0.023, P =0.007, and P <0.001, respectively). The results of logistic regression analysis adjusted for confounding factors also showed that compared with the gauze group, the PVAS group was significantly less likely to experience packing dropout (odds ratio=0.13; 95% confidence interval, 0.06-0.29, P <0.001) for which younger and older age and allergic rhinitis were independent risk factors. In conclusion, both gauze and PVAS are effective packing materials as internal splints after closed reduction of nasal bone fractures. Specifically, PVAS utilization warrants consideration in pediatric and geriatric populations, individuals with allergic rhinitis, and those at elevated risk of bleeding.

Plastic Wound Protector vs Surgical Gauze for Surgical Site Infection Reduction in Open GI Surgery

Surgical site infections (SSIs) are prevalent hospital-acquired infections with significant patient impacts and global health care burdens. The World Health Organization recommends using wound protector devices in abdominal surgery as a preventive measure to lower the risk of SSIs despite limited evidence. To examine the efficacy of a dual-ring, plastic wound protector in lowering the SSI rate in open gastrointestinal (GI) surgery irrespective of intra-abdominal contamination levels. This multicenter, patient-blinded, parallel-arm randomized clinical trial was conducted from August 2017 to October 2022 at 13 hospitals in an academic setting. Patients undergoing open abdominal bowel surgery (eg, for bowel perforation) were eligible for inclusion. Patients were randomized 1:1 to a dual-ring, plastic wound protector to protect the incision site of the abdominal wall (experimental group) or a conventional surgical gauze (control group). The primary end point was the rate of SSI within 30 days of open GI surgery. A total of 458 patients were randomized; after 1 was excluded from the control group, 457 were included in the intention-to-treat analysis (mean [SD] age, 58.4 [12.1] years; 256 [56.0%] male; 341 [74.6%] with a clean-contaminated wound): 229 in the wound protector group and 228 in the surgical gauze group. The overall SSI rate in the intention-to-treat analysis was 15.7% (72 of 458 patients). The SSI rate for the wound protector was 10.9% (25 of 229 patients) compared with 20.5% (47 of 229 patients) with surgical gauze. The wound protector significantly reduced the risk of SSI, with a relative risk reduction (RRR) of 46.81% (95% CI, 16.64%-66.06%). The wound protector significantly decreased the SSI rate for clean-contaminated wounds (RRR, 43.75%; 95% CI, 3.75%-67.13%), particularly for superficial SSIs (RRR, 42.50%; 95% CI, 7.16%-64.39%). Length of hospital stay was similar in both groups (mean [SD], 15.2 [10.5] vs 15.3 [10.2] days), as were the overall postoperative complication rates (20.1% vs 18.8%). This randomized clinical trial found a significant reduction in SSI rates when a plastic wound protector was used during open GI surgery compared with surgical gaze, supporting the World Health Organization recommendation for use of wound protector devices in abdominal surgery. ClinicalTrials.gov Identifier: NCT03170843.

MXene/TPU Hybrid Fabrics Enable Smart Wound Management and Thermoresponsive Drug Delivery.

Thermoresponsive wound dressings with real-time monitoring and on-demand drug delivery have gained significant attention recently. However, such smart systems with stable temperature adjustment and drug release control are still lacking. Here, a novel smart fabric is designed for wound management with thermoresponsive drug delivery and simultaneously temperature monitoring. The triple layers of the fabrics are composed of the drug-loaded thermoresponsive nanofiber film, the MXene-optimized joule heating film, and the FPCB control chip. The precise and stable temperature stimulation can be easily achieved by applying a low voltage (0-4 V) to the heating film, achieving the temperature control ranging from 25 to 130 °C. And the temperature of the wound region can be monitored and adjusted in real time, demonstrating an accurate and low-voltage joule heating capability. Based on that, the drug-loaded film achieved precise thermoresponsive drug release and obtained significant antibacterial effects in vitro. The in vivo experiments also proved the hybrid fabric system with a notable antibacterial effect and accelerated wound healing process (about 30% faster than the conventional gauze group).

Process optimization and character evaluation of Bletilla striata polysaccharide (BSP) and chitosan (CS) composite hemostatic sponge (BSP-CS).

Bletilla striata polysaccharide (BSP) and chitosan (CS) were chemically cross-linked using oxalyl chloride to prepare a composite hemostatic sponge (BSP-CS), and the process parameters were optimized using the Box-Behnken design (BBD) with response surface methodology. To optimize the performance of the hemostatic sponge, we adjusted the ratio of independent variables, the amount of oxalyl chloride added, and the freeze-dried volume. A series of evaluations were conducted on the hemostatic applicability of BSP-CS. The characterization results revealed that BSP-CS had a stable bacteriostatic effect on Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa within 72 h, and the bacteriostatic rate was above 30%. The CCK-8 cytotoxicity test demonstrated that BSP-CS had a certain effect on promoting cell proliferation of L929 cells. In the mouse tail-cutting experiment, the hemostasis time of BSP-CS was 463.0±38.16 s, shortened by 91.3 s on average compared with 554.3±34.67 s of the gauze group. The blood loss of the BSP-CS group was 28.47±3.74 mg, which was 34.7% lower than that of the control gauze group (43.6±3.83 mg). In the in vitro coagulation experiment, the in vitro coagulation index of the BSP-CS group was 97.29%±1.8%, which was reduced to 8.6% of the control group. The CT value of the BSP-CS group was 240±15 s, which was 155 s lower than that of the gauze group (355±31.22 s). All characterization results indicate that BSP-CS is an excellent hemostatic material.

Short and long-term menstrual, reproductive, and mental health outcomes after the intrauterine use of chitosan tamponade or the Bakri balloon for severe postpartum hemorrhage: an observational study

Objective This retrospective follow-up study analyzes the effect of intrauterine postpartum hemorrhage (PPH) therapy on menstrual, reproductive, and mental health outcomes. Methods All women who delivered at a university hospital between 2016 and 2021 with PPH and who needed intrauterine therapy were included. A questionnaire on well-being, menses, fertility, and reproductive outcomes was mailed to the patients. Those who did not reply were surveyed by telephone. Results A total of 214 women treated with chitosan-covered gauze (group A) and 46 women treated with a balloon tamponade (group B) were recruited, and their short-term courses were analyzed. For long-term follow-up, 71 women of group A (33%) and 21 women of group B (46%) could be reached. A total of 89% of group A and 95% of group B had regular menstrual bleeding in the most recent 12 months; 27% (group A) and 29% (group B) were trying to conceive again, and all of them did so successfully. There were 12 deliveries, 3 ongoing pregnancies, 3 miscarriages, and 2 terminations of pregnancies (TOP) in group A and 4 deliveries, 1 miscarriage, and 2 TOPs in group B. More than half of our study participants was sorted into grade II or III of the Impact of Events Scale, indicating they experienced clinical impacts in the form of psychological sequelae. One-quarter of patients had symptoms of post-traumatic stress disorder. Conclusion Chitosan gauze as well as balloon tamponade appear to have few adverse effects on subsequent menstrual and reproductive function. Women after PPH are at increased risk of long-term adverse psychological outcomes.

A double cross-linked anisotropic quaternized chitosan/sodium alginate-based wound dressing for rapid drainage of biofluids

Excessive biofluid around wounds can cause infection and prevent healing. In this study, an anisotropic quaternized chitosan (QC)/sodium alginate (AL)-based aerogel wound dressing was prepared via a directional freeze-drying technique inspired by the channel structure used for water transport in trees. The aligned channels provided the dressing with self-pumping ability, allowing it to rapidly and completely remove biofluids and absorb biofluids up to 1292.5 % of its own weight. To enhance the strength of the dressing, a double cross-linked network was constructed based on the QC-AL electrostatic attraction and AL-Ca2+ chelation interaction. The axial compressive strength of the double cross-linked dressing reached 207.3 kPa (ε = 50 %). In addition, the dressing exhibited strong conductive properties (conductivity = 13.0 S/m), antioxidant activities [reactive oxygen species (ROS) scavenging ability = 88.0 %], and hemostatic characteristics (blood coagulation index = 1.8 %). The dressing also exhibited powerful antibacterial performance, exhibiting over 98.0 % inhibition of E. coli and S. aureus. Experiments on diabetic mouse models revealed that the dressing considerably promoted wound healing. On day 3, the wound healing rate was 96.7 % faster in the QAC group than in the gauze group. Therefore, the developed dressing may have great potential for chronic wound care.

A modified chain-based sponge dressing controls junctional hemorrhage in the tactical combat casualty care simulation of pigs

BackgroundHemorrhage has always been the focus of battlefield and pre-hospitalization treatment. With the increasing fatality rates associated with junctional bleeding, treatment of bleeding at junctional sites has gradually gained attention in battlefield trauma emergency care. We designed a modified chain-based sponge dressing with a medical polyvinyl alcohol sponge that can be used to treat junctional hemorrhage and tested its hemostatic efficacy and biocompatibility.MethodsTwenty adult Bama miniature pigs were randomly divided into the modified chain-based sponge dressing (MCSD) and standard gauze (SG) groups. The right femoral artery of the pigs was shot at after anesthesia. The Bama miniature pigs were moved to the safety zone immediately to assess the condition according to the MARCH strategy, which evaluates massive hemorrhaging, airway obstruction, respiratory status, circulatory status, head injury & hypothermia. Hemoglobin and coagulation status were checked during the experiment.Among the pigs in which the inguinal hemorrhagic model based on bullet penetrating wounds was successfully established, those in the MCSD group received a disinfected MCSD for hemostasis, while those in the SG group received standard gauze in an imbricate manner to pack the bullet exit and entrance wounds to stop bleeding until the wound was filled, followed by compression for 3 min at sufficient pressure. CT scanning, transmission electron microscopy, and HE staining were conducted after experiment.ResultsThe MCSD group showed lower hemostasis time and blood loss than the gauze group. The MCSD group also showed a higher success rate of treatment,more stable vital signs and hemoglobin level. The CT scanning results showed tighter packing without large gaps in the MCSD group. The histopathological assessments and the transmission electron microscopy and HE staining findings indicated good biocompatibility of the polyvinyl alcohol sponge.ConclusionThe MCSD met the battlefield’s requirements of speedy hemostasis and biosafety for junctional hemorrhage in Bama miniature pigs. Moreover, in comparison with the conventional approach for hemostasis, it showed more stable performance for deep wound hemostasis. These findings provide the theoretical and experimental basis for the application of MCSD in the treatment of hemorrhage in the battlefield in the future.

Efficacy of four different hemostatic agents in thyroid surgery in reducing the amount of post-operative fluid collection

PurposesPostoperative bleeding remains a life-threatening complication in thyroid surgery. The aim was to assess the efficacy of four different hemostatic agents, Collagen-Fibrinogen-Thrombin Patch (CFTP) in two sizes (3 × 2.5 cm and 9.5 × 4.8 cm), polysaccharide particles (1 g) and Cellulose Gauze (2.5 × 5 cm) on postoperative drainage volume (DV) compared to a control group.MethodsWe included from October 2007 until Mai 2011, 150 patients (30 per group) for this monocentric, retrospective case-controlled study. Patients were scheduled for a hemithyroidectomy or thyroidectomy. The primary endpoint was the postoperative DV within the first 24 h, secondary the incidence of adverse events.ResultsThere were no difference in demographic parameters. The mean DV (± SD) was 51.15 (± 36.86) ml in the control, 50.65 (± 42.79) ml in small (3 × 2.5 cm), 25.38 (± 23.99) ml in large CFTP (9.5 × 4.8 cm), 53.11 (± 39.48) ml in the polysaccharide particles and 48.94 (± 30.59) ml in the cellulose gauze group. DV was significantly reduced with the large CFTP (p < 0.05) compared to all other groups. There were no adverse events.ConclusionsWe were able to demonstrate a significant reduction in the DV for the large CFTP group compared to the other collectives. Although this as being associated with not inconsiderable costs and we would only recommend its use for high-risk patients only.

A Multifunctional Polyethylene Glycol/Triethoxysilane-Modified Polyurethane Foam Dressing with High Absorbency and Antiadhesion Properties Promotes Diabetic Wound Healing.

The delayed healing of chronic wounds, such as diabetic foot ulcers (DFUs), is a clinical problem. Few dressings can promote wound healing by satisfying the demands of chronic wound exudate management and tissue granulation. Therefore, the aim of this study was to prepare a high-absorption polyurethane (PU) foam dressing modified by polyethylene glycol (PEG) and triethoxysilane (APTES) to promote wound healing. PEG-modified (PUE) and PEG/APTES-modified (PUESi) dressings were prepared by self-foaming reactions. Gauze and PolyMem were used as controls. Next, Fourier transform-infrared spectroscopy, thermomechanical analyses, scanning electron microscopy and tensile strength, water absorption, anti-protein absorption, surface dryness and biocompatibility tests were performed for in vitro characterization. Wound healing effects were further investigated in nondiabetic (non-DM) and diabetes mellitus (DM) rat models. The PUE and PUESi groups exhibited better physicochemical properties than the gauze and PolyMem groups. Moreover, PUESi dressing showed better anti-adhesion properties and absorption capacity with deformation. Furthermore, the PUESi dressing shortened the inflammatory phase and enhanced collagen deposition in both the non-DM and DM animal models. To conclude, the PUESi dressing not only was fabricated with a simple and effective strategy but also enhanced wound healing via micronegative-pressure generation by its high absorption compacity with deformation.

DRY GAUZE AND IODINE TULLE DRESSINGS FOR THE PREVENTION OF INFECTION IN PATIENTS WITH A LOWER LIMB EXTERNAL FIXATOR: A RETROSPECTIVE OBSERVATIONAL STUDY

DRY GAUZE AND IODINE TULLE DRESSINGS FOR THE PREVENTION OF INFECTION IN PATIENTS WITH A LOWER LIMB EXTERNAL FIXATOR: A RETROSPECTIVE OBSERVATIONAL STUDY

Reducing Surgical Site Infections with Silver-impregnated Dressings in Lower Extremity Bypass Patients

Surgical site infection (SSI) after lower extremity (LE) bypass surgery is associated with longer length of stay, higher hospital cost, increased morbidity, and even graft loss. Silver-impregnated dressings have been used by other surgical subspecialties to decrease SSI with reported success. The National Surgical Quality Improvement Program (NSQIP) published a national expected rate of 7.9% for SSI after LE bypass surgery. In 2018, our institutional SSI rate was 12.8%. To reduce this rate, we transitioned to silver-impregnated dressings for all LE bypass procedures and studied the subsequent impact on SSIs. We used NSQIP data to retrospectively study two consecutive cohorts of vascular surgery patients at a single institution who underwent LE bypasses. Patients in 2019 underwent the standard of care surgery with standard sterile gauze postoperative dressings. Patients in 2020 underwent standard of care surgery and were treated with silver-impregnated dressings. NSQIP criteria were used to determine if patients developed SSIs within 30 days of surgery. The Fischer exact and χ2 tests were used to compare groups before and after the intervention. A total of 282 patients underwent LE bypass in 2019 and 2020. The standard of care cohort had 168 patients with sterile gauze dressings, whereas the cohort after intervention had 114 patients with silver-impregnated dressings. The groups were similar in terms of demographics and comorbidities (Table). When considering all classifications of SSI, there were significantly fewer infections in the silver dressing group compared with the sterile gauze group (9.6 % vs 20.8%; P = .014). There was a non-statistically significant reduction in readmissions and unplanned return to the operating room in the silver dressing group. This study demonstrated a significantly lower rate of SSIs in patients undergoing LE bypass with use of a silver-impregnated dressing when compared with a sterile gauze dressing. Although our study does not demonstrate a causal relationship, this relatively inexpensive and low-risk intervention's association with a significant decrease in an otherwise very serious postoperative complication argues for a change in clinical practice or prospective confirmatory studies to optimize patient outcomes after LE bypass.TableDemographic and comorbidity differences between groups of patients who underwent lower extremity (LE) bypass surgery using sterile gauze dressing (2019) and silver-impregnated dressing (2020), and NSQIP-collected outcomes regarding postoperative surgical site infection (SSI), wound dehiscence, unplanned return to operating room, and readmission within 30 daysSterile gauze (n = 168)Silver dressing (n = 114)P-valueMale gender109 (64.8)79 (69.3).5Age, years67.1 (10.8)66.0 (11.2).4Race.7 Asian1 (0.6)2 (1.8) Black or African American25 (14.9)13 (11.4) Unknown11 (6.5)7 (6.1) White131 (78.0)92 (80.7)Emergent surgery10 (5.9)4 (3.5).4Active smoker78 (46.4)52 (45.6).9Diabetes.4 Yes, insulin-dependent47 (28.0)39 (34.2) Yes, non-insulin-dependent32 (19.1)23 (20.2) No89 (53.0)52 (45.6)Hypertension133 (79.2)93 (81.6).6Chronic obstructive pulmonary disease26 (15.5)15 (13.2).6Dialysis10 (5.9)10 (8.8).4Superficial SSI35 (20.8)11 (9.7).014Deep SSI5 (3.0)2 (1.8).7Organ space SSI2 (1.2)6 (5.3).07Wound dehiscence6 (3.6)5 (4.4).8Unplanned return to operating room43 (25.6)32 (28.1).7Readmission39 (23.2)30 (26.3).2Data are presented as mean (standard deviation) or number (%). Open table in a new tab

Triticum vulgare Extract and Polyhexanide (Fitostimoline® Hydrogel/Fitostimoline® Plus Gauze) versus Saline Gauze Dressing in Patients with Diabetic Foot Ulcers: Results of a Randomized Controlled Trial.

The use of dressings is an essential component of the standard of care for diabetic foot ulcers (DFUs); however, despite the wide variety of dressings available, there is a lack of evidence from head-to-head randomized controlled trials. We evaluated the efficacy and safety of Triticum vulgare extract and polyhexanide (Fitostimoline® hydrogel/Fitostimoline® Plus gauze) versus saline gauze dressings in patients with DFUs. This study involved a monocentric, two-arm, open-label, controlled trial in patients with DFUs (Grades I or II, Stage A or C, based on the Texas classification) randomized to 12 weeks of dressing with Fitostimoline® hydrogel/Fitostimoline® Plus gauze or saline gauze. The number of patients with complete healing, the reduction in DFU size, and the presence of local signs and symptoms of the wound and perilesional skin were evaluated every two weeks and at the end of treatment. A total of 40 adult patients were recruited (20 patients in each treatment group). The proportion of patients with complete healing was similar between the two groups (61% vs. 74%, p = 0.495, Fitostimoline® hydrogel/Fitostimoline® Plus gauze vs. saline gauze, respectively), without significant differences, as well as the reduction in DFU size. A significant improvement in local signs and symptoms of the wound and signs of perilesional skin in the Fitostimoline® hydrogel/Fitostimoline® Plus gauze compared with the saline gauze group was observed. In a clinical setting, the use of Fitostimoline® hydrogel/Fitostimoline® Plus gauze dressing in patients with DFUs significantly improves signs and symptoms of the wound and signs of perilesional skin compared with saline gauze dressing with a similar efficacy in terms of wound healing.

D150. Effectiveness of Traumatic Wounds Treatment with Negative-pressure Wound Therapy with Instillation: Pragmatic Randomized Control Trial

PURPOSE: Negative Pressure Wound Therapy (NPWT) has been associated with instillation (NPWTi) to provide cleaning cycles combined with vacuum therapy, avoiding constant dressings changes. NPWTi meets the treatment demands of wounds at risk infection. The aim of this study is to compare clinical results and direct costs of soft tissue traumatic wounds treatment submitted to three different coverings. METHODS: Prospective, pragmatic randomized controlled trial evaluating adult patients with traumatic wounds. 120 patients with 131 wounds were randomized to standard of care, mainly with layers of gauze (n=41), conventional NPWT (n=46), and NPWTi (n=44). Negative pressure was set at -125 mmHg in continuous mode, applied for two hours in the NPWTi group, followed by normal saline instillation with 20 minutes of dwell time. RESULTS: Sample consisted of 120 patients from 139 screened for eligibility. The mean age was 37.3 (SD14.9; min16;max86) years, primarily male (78%) with low Charlson Index (0.36;SD 1.0). Wounds were mainly degloving injuries (57%) with a mean size of 192 cm2 (min13; max1303), affecting predominantly lower extremities (85%), caused by vehicle accidents. There were no statistical differences between groups regarding baseline data. Wound time of closure (in days) was lower in the instillation group (9.2NPWTi; 11.5NPWT;14.6Layering; p=0.005), as well as the number of surgical procedures (2.9NPWTi; 3.5NPWT;6.9 Layering; p<0.001). Length of stay (in days) was slightly lower in the NPWT group (25.1NPWT;27.8NPWTi;29.1Layering; p=0.226). Costs (in $USD) were higher in the Gauze group ($5510NPWTi; $5,643NPWT;$7,162Gauze;p=0.873). CONCLUSION: Negative pressure with or without installation therapy was more effective and less costly than gauze therapy in treating complex traumatic wounds.

Effects of Different Preparation Methods on Microbiota Composition of Fecal Suspension.

Fecal microbiota transplantation is an emerging disease-modifying therapy. The viability of the microbiome in feces and its successful transfer depends on the preparation of fecal microbiota suspension. However, currently, no standard operation procedure is proposed for fecal suspension preparation. This study aims to compare the effect of different preparation methods on the composition of fecal microbiota composition in the rat. Four methods were used to collect the fecal suspension from fresh rat fecal (Group A), including stirring with normal saline (Group B), stirring with normal saline and then standing (Group C), stirring with normal saline and filtered with gauze (Group D), and stirring with normal saline and centrifuged (Group E). 16S ribosomal RNA gene (16S rDNA) sequencing technology was used to analyze the microbiota diversity and composition of each group of samples. Compared with fresh feces, the bacterial richness of the fecal suspension obtained by the four methods was significantly decreased (P < 0.05). The structural similarity with fresh fecal microbiota from high to low is groups B, D, C, and E. All four methods changed the microbiota structure to varying degrees, thus may affect the effect of FMT. In conclusion, choosing different methods to prepare fecal suspensions may help to better optimize the application of FMT.

Biological Application of Novel Biodegradable Cellulose Composite as a Hemostatic Material.

Degradable hemostatic materials have unique advantages in reducing the amount of bleeding, shortening the surgical operation time, and improving patient prognosis. However, none of the current hemostatic materials are ideal and have disadvantages. Therefore, a novel biodegradable cellulose-based composite hemostatic material was prepared by crosslinking sodium carboxymethyl cellulose (CCNa) and hydroxyethyl cellulose (HEC), following an improved vacuum freeze-drying method. The resulting cellulose composite material was neutral in pH and spongy with a density of 0.042 g/cm3, a porosity of 77.68%, and an average pore size of 13.45 μm. The composite's compressive and tensile strengths were 0.1 MPa and 15.2 MPa, respectively. Under in vitro conditions, the composites were degraded gradually through petite molecule stripping and dissolution, reaching 96.8% after 14 days and 100% degradation rate at 21 days. When implanted into rats, the degradation rate of the composite was slightly faster, reaching 99.7% in 14 days and 100% in 21 days. Histology showed a stable inflammatory response and no evidence of cell degeneration, necrosis, or abnormal hyperplasia in the tissues around the embedded material, indicating good biocompatibility. In the hemorrhagic liver model, the time to hemostasis and the total blood loss in the cellulose composite group was significantly lower than in the medical gauze group and the blank control group (P < 0.05). These data indicate that the novel cellulose composite is a promising implantable hemostatic material in clinical settings.

Nicaraven-loaded electrospun wound dressings promote diabetic wound healing via proangiogenic and immunomodulatory functions: a preclinical investigation.

The current study developed a biopolymer-based wound dressing by electrospinning of Nicaraven-loaded collagen solution. Firstly, collagen was dissolved in acetic acid, and then Nicaraven was added to the polymeric solution at three different concentrations of 2 w/w%, 4 w/w%, and 6 w/w%. The resulting solution was then electrospun. Various experiments were performed to characterize the produced wound dressings. In vitro studies showed that Nicaraven-loaded scaffolds were not toxic against L929 fibroblast cells and protected them against oxidative stress. Wound healing potential of different formulations of Nicaraven-loaded collagen wound dressings was studied in a rat model of the excisional diabetic wound. The study showed that the collagen/4% Nicaraven and collagen/6% Nicaraven wound dressings exhibited a significantly higher percentage of wound closure, the thickness of the epithelium, and collagen deposition compared with collagen/2% Nicaraven, collagen-only, and sterile gauze groups. Gene expression study showed that the developed wound dressings reduced the tissue expression levels of glutathione peroxidase, NFKβ, and matrix metalloproteinase 9 (MMP9) genes. In addition, in the wounds treated with collagen/4% Nicaraven and collagen/6% Nicaraven scaffolds, wound healing was associated with a higher tissue expression level of b-FGF, VEGF, and collagen type I genes. Overall, wound healing activity of collagen/4% Nicaraven and collagen/6% Nicaraven wound dressings was not significantly different. This study implies that collagen wound dressings incorporated with 4% and 6% Nicaraven can be considered a potential candidate to treat diabetic wounds in the clinic.

N, O-carboxymethyl chitosan/oxidized cellulose composite sponge containing ε-poly-l-lysine as a potential wound dressing for the prevention and treatment of postoperative adhesion

Herein, we designed and fabricated a biodegradable composite sponge which main component contained N, O-carboxymethyl chitosan (N,O-CS) and oxidized cellulose nanocrystals (TOCN) as a potential wound dressing for the prevention and treatment of postoperative adhesion. In order to improve antimicrobial properties of N,O-CS/TOCN composite sponges, natural antimicrobial agents (ε-Poly-l-Lysine，EPL) were successfully introduced and the EPL/N,O-CS/TOCN composite sponge exhibited excellent antibacterial properties and biological security. The EPL/N,O-CS/TOCN composite sponge can be degraded in vivo within 3 weeks. Finally, we analyzed the anti-adhesion performance of EPL/N,O-CS/TOCN composite sponge through a rat model of sidewall defect-cecum abrasion. These results demonstrated that EPL/N,O-CS/TOCN-treated group can effectively reduce the peritoneal adhesion formation than the commercial soluble gauze group and normal saline group, which mainly attribute to the excellent hemostatic function and tissue repair function of EPL/N,O-CS/TOCN composite sponge. It is believed that the EPL/N,O-CS/TOCN composite sponge will prove to be as a new medical device treat the internal tissue/organ repair and simultaneous prevention of postoperative adhesion.

A novel recombinant human collagen hydrogel as minced split-thickness skin graft overlay to promote full-thickness skin defect reconstruction

To overcome limited donor-site availability in patients with extensive burns, split-thickness skin grafts (STSGs) are sometimes minced into micrografts (MGs) to improve the expansion ratio of the grafts, but this may reduce wound healing. We aimed to produce a novel hydrogel as an overlay of minced STSGs to improve wound healing. The new hydrogel was produced using recombinant human collagen type III powder as a raw material. Morphological and physical characteristics (degradation and swelling rate), cytotoxicity, and cell viability of the hydrogel were evaluated in vitro. A full-thickness in vivo skin defect model was constructed with male Sprague-Dawley rats. The animals were randomly assigned to experimental and control groups in which the new hydrogel and Vaseline gauze, respectively, were overlaid on minced STSGs to repair and regenerate skin wound. The healing rates and recovery status were compared between the two groups. The hydrogels exhibited good water retention properties and a suitable degradation rate, which can promote the proliferation and migration of wound healing-related cells in vitro. Further, using the hydrogel as an overlay accelerated wound closure and angiogenesis, increased dermal tissue and basement membrane formation, enhanced collagen synthesis and wound healing-related growth factor expression, while reducing scar formation compared to the Vaseline gauze group. In conclusion, the novel, low-cost recombinant human collagen hydrogel can accelerate wound closure and improve wound healing when used as an overlay of minced STSGs. The new hydrogel could become a new treatment option for traumatic skin wounds caused by burns or injuries.

Amniotic membrane dressing versus nitrofurazone-impregnated dressing in the treatment of second-degree burn wounds: a randomized clinical trial.

Both the amniotic membrane biologic dressing and nitrofurazone-impregnated dressing are treatment options for burn wounds. To compare the efficacy of these treatments in healing second-degree burns, a randomized clinical trial was conducted among patients with second-degree burns who had no comorbidities or history of addiction and were referred to a burn center in Urmia, Iran, between December 2017 and September 2019. Patients were randomly assigned to one of 2 study groups. Wounds were dressed in either amniotic membrane covered with moistened gauze/petrolatum or nitrofurazone-impregnated gauze. Comparative groups were matched according to percentage of burn (total body surface area). The dressing application occurred once daily in the nitrofurazone group and once weekly in the amniotic membrane group. The study was conducted until all wounds healed. The study outcomes included the infection rate of the wound, pain severity related to dressing changes, dressing change frequency, epithelialization rate, hospitalization length of stay, morphine use, and scarring. Data were collected in real time by the researcher via observation, interview, examination of the patient, and, eventually, completion of a checklist. Analyzed quantitative and qualitative variables were reported as mean ± standard deviation and percentage (frequency). Each group included 35 participants (24 men, 11 women; age, 20.05 ± 3.60 years in the amniotic dressing group; and 20 men, 15 women; age, 21.60 ± 2.02 years in the nitrofurazone-impregnated gauze group). Assessment was performed on days 1, 7, 14, and 30 from the initial treatment and at discharge. No significant difference was noted in the rate of infection between the 2 groups. Epithelialization was complete (100%) by day 7 in the amniotic membrane group, versus 77% in the nitrofurazone group. Pain following dressing application, length of hospitalization, morphine use, and scarring at day 14 were significantly lower (P < .05) in the amniotic membrane group. This study indicated that the use of amniotic membrane dressing improved factors key to healing in second-degree burn wounds compared with nitrofurazone-impregnated dressing. Further research with a larger sample is warranted.