142 research outputs found

    Whole blood in prehospital damage control resuscitation : -Safety, feasibility, and logistics

    Get PDF
    Bakgrunn De siste tiårene har det vært et paradigmeskifte i behandlingen av blødningsjokk. Skadebegrensende resuscitering har som hensikt å understøtte hemostatisk evne hos pasienten og reversere og dempe konsekvensene av sjokk slik at pasienten har tilstrekkelige fysiologiske reserver til å overleve påfølgende behandling i sykehus. Strategien baserer seg i all hovedsak på å starte tidlig behandling med blod og blodprodukter. I økende grad har sivile og militære prehospitale tjenester vurdert fullblod som et alternativ for den intiale resusciteringen av blødningsjokk. Selv om fullblod har tiltalende egenskaper er det flere utfordringer ved implementering av fullblod i et prehospitalt system. Forhold knyttet til sikkerhet, logistikk, lagring og praktisk bruk bør evalueres. Mål Å undersøke og evaluere implementeringen av et program for implementering av prehospitalt lavtiter gruppe O fullblod (LTOWB). Metode Paper I undersøkte gjennomførbarhet, sikkerheten og effektivitet av intraossøs sternal autolog re-infusjon av varmt friskt fullblod (WFWB) i en prospektiv human komparativ studie. Paper II undersøkte ex vivo kvaliteten til lav titer type O fullblod (LTOWB) under fremskutt lagring i opptil 21 dager i en lufttett temperaturregulert beholder ved en luftambulansebase sammenlignet med LTOWB lagret i blodbanken. Paper III identifiserte nåværende prehospitale blodtransfusjonsprogrammer, fremtidige behov og potensielle barriærer for implementering av LTOWB i en spørreundersøkelse blant medisinsk ansvarligeleger ved luft og redningshelikoptertjenestene i Norge. Paper IV beskrev implementeringen av et LTOWB-transfusjonsprogram i Luftambulansetjenesten i Bergen i perioden 2015-2020 i en prospektiv observasjonsstudie. Resultater Det var ingen hemolyse etter sternal intraossøs re-infusjon av fullblod. Median infusjonshastighet var 46,2 ml/min for FAST-1-IO nålen, og feilraten ved innleggelse av IO tilgangen for uerfarent personell var 9 %. Fremskutt lagring av LTOWB opptil 21 dager førte ikke til konsekvenser som kan true pasientsikkerheten. Blodet tilfredstilte EU krav i hele lagringsperioden. Det var ingen signifikante forskjeller i de hematologiske variablene, blodplateaggregering eller viskoelastiske egenskaper mellom blod lagret fremskutt og blod lagret i blodbanken. Alle luft og redningshelikopter i Norge har blodprodukter tilgjengelig. Fire av 20 (20 %) har implementert LTOWB. Et flertall av tjenestene har en preferanse for LTOWB siden dette muliggjør tidlig balansert transfusjon og kan ha logistiske fordeler i tidskritiske situasjoner. Blodbanker som leverer LTOWB rapporterer gunstige erfaringer. I løpet av 2015-2020 responderte Luftambulansen i Bergen til 5124 pasienter. Syttito (1,4%) mottok blodtransfusjon. 52 pasientene samtykket til deltagelse i studien. Av disse fikk 48 LTOWB. Førtiseks (88 %) ble innlagt på sykehuset i live, og 76 % av disse fikk ytterligere transfusjoner i løpet av de første 24 timene. De fleste pasienter presenterte med stump skademekanikk (69 %), etterfulgt av blødninger som ikke var relatert til traumer (29 %). Totalt overlevde 36 (69%) 24 timer, og 28 (54%) overlevde 30 dager. Ingen transfusjonsreaksjoner eller logistiske problemer ble rapportert. Konklusjon Intraossøs infusjon av WFWB er trygt, pålitelig og gir tilstrekkelig flow for den initielle resuscitering ved blødningsjokk. Fremskutt lagring av LTOWB i Luftambulansetjenesten er gjennomførbart og trygt. Kvalitet tilfredstiller EU krav opptil 21 dagers lagring, og hemostatiske egenskaper e LTOWB sammenlingbar med LTOWB lagret i blodbanken. Luftambulansetjenestene og blodbankene som leverer LTOWB har gode erfaringer med implementering av LTOWB. Våre undersøkelser viser at implementering av et prehospitalt transfusjonsprogram med fullblod er mulig og sikkert. Det er videre behov for studier som ser på effektiviteten av fullblod sammenlignet med blodkomponenter.Background In the last two decades, resuscitation of hemorrhagic shock has undergone a paradigm shift. Modern damage control resuscitation strategies aim to improve outcomes by facilitating early hemostatic resuscitation with blood and blood products. The ultimate goal is to prevent, reverse or mitigate the severity and duration of shock and its consequences until definitive hemorrhage control can be achieved. As a result, both civilian and military EMS systems are considering whole blood for prehospital resuscitation of hemorrhagic shock. Although appealing, establishing a robust system for forward resuscitation with whole blood is challenging as several vital factors regarding safety, logistics, and implementation barriers need to be considered. Aim To investigate and evaluate the implementation of a pre-hospital low titer group O whole blood (LTOWB) transfusion program. Methods Paper I investigated the feasibility, safety, and efficacy of autologous re-infusion of warm fresh whole blood (WFWB) through an intraosseous sternal device in a prospective human comparative study. Paper II investigated the ex vivo quality of LTOWB during storage for up to 21 days in an airtight thermal container at a helicopter emergency medical system (HEMS) base compared to LTOWB stored in the blood bank. Paper III identified current pre-hospital blood transfusion programs, future needs, and potential obstacles in implementing LTOWB in a national survey among the medical directors of the Norwegian HEMS and Search and Rescue (SAR) helicopter bases. Finally, in a prospective observational study, paper IV described and evaluated the implementation of a LTOWB program in one of the Norwegian HEMS services in 2015-2020. Results There was no evidence of hemolysis following sternal intraosseous re-infusion of whole blood. The median infusion rate was 46.2mL/min for the FAST-1 device, and the failure rate for inexperienced personnel was 9%. Storage of LTOWB complied with the EU regulations throughout remote and in- hospital storage for 21 days. In addition, there were no significant differences in hematology variables, platelet aggregation, or viscoelastic properties between blood stored remotely and in the blood bank. All HEMS and SAR helicopter services in Norway carry LTOWB or blood components. A majority of services have a preference for LTOWB because LTOWB enables early balanced transfusion and may have logistical benefits in time-critical emergencies. This far, four of 20 (20%) have implemented LTOWB. Blood banks and services that provide LTOWB report favorable experiences. During the five years, the Bergen HEMS in study IV responded to 5124 patients. Seventy-two (1.4%) were transfused. Twenty patients were excluded mainly due to a lack of informed consent. Of the 52 patients, 48 received LTOWB. Forty-six (88%) were admitted to the hospital alive, and 76% of these received additional transfusions during the first 24 hours. Most patients presented with blunt trauma mechanisms (69%), followed by hemorrhage unrelated to trauma (29%). Overall 36 (69%) survived 24 hours, and 28 (54%) survived 30 days. No suspected transfusion reactions or logistical issues were reported. Conclusion WFWB transfusion through the IO route is safe, reliable, and provides sufficient flow for the initial resuscitation of hemorrhagic shock. Storage of LTOWB in thermal containers in a pre-hospital HEMS service is feasible and safe. Hemostatic properties are present for up to 21 days of storage and are similar to LTOWB stored in the blood bank. HEMS services and blood banks report favorable experiences implementing and utilizing LTOWB in Norway. The logistics of LTOWB emergency transfusions are manageable and safe in a Norwegian HEMS service.Doktorgradsavhandlin

    Unveiling the role of artificial intelligence for wound assessment and wound healing prediction

    Get PDF
    Wound healing is a very dynamic and complex process as it involves the patient, wound-level parameters, as well as biological, environmental, and socioeconomic factors. Its process includes hemostasis, inflammation, proliferation, and remodeling. Evaluation of wound components such as angiogenesis, inflammation, restoration of connective tissue matrix, wound contraction, remodeling, and re-epithelization would detail the healing process. Understanding key mechanisms in the healing process is critical to wound research. Elucidating its healing complexity would enable control and optimize the processes for achieving faster healing, preventing wound complications, and undesired outcomes such as infection, periwound dermatitis and edema, hematomas, dehiscence, maceration, or scarring. Wound assessment is an essential step for selecting an appropriate treatment and evaluating the wound healing process. The use of artificial intelligence (AI) as advanced computer-assisted methods is promising for gaining insights into wound assessment and healing. As AI-based approaches have been explored for various applications in wound care and research, this paper provides an overview of recent studies exploring the application of AI and its technical developments and suitability for accurate wound assessment and prediction of wound healing. Several studies have been done across the globe, especially in North America, Europe, Oceania, and Asia. The results of these studies have shown that AI-based approaches are promising for wound assessment and prediction of wound healing. However, there are still some limitations and challenges that need to be addressed. This paper also discusses the challenges and limitations of AI-based approaches for wound assessment and prediction of wound healing. The paper concludes with a discussion of future research directions and recommendations for the use of AI-based approaches for wound assessment and prediction of wound healing

    Chitosan-based Composite for Wound Healing & Biomedical Applications

    Get PDF
    Polymer composites have witnessed increased research interest in the last decades, and the applications of these materials include drug delivery, tissue engineering, and wound bandages and dressings. Numerous polymers have been studied to fabricate the ideal wound dressing. Making these polymer composites biocompatible, porous, and bioactive with high absorption capabilities is critical to guide cell growth and differentiation and limit their detrimental effects on incorporated therapeutic molecules. This research work aims to address shortcomings of available wound dressings by fabricating a biocompatible, porous, bioactive, and antimicrobial dressing using chitosan (CTS) and carboxymethyl cellulose (CMC) polymers incorporated with zinc-doped halloysites (ZnHNT). In line with the points mentioned earlier, three distinct objectives are proposed in this research that involve using natural biopolymers and nanomaterials. The first objective involves the fabrication and characterization of chitosan/carboxymethylcellulose composite incorporated with zinc-coated halloysites (HNTs) via the solution-gel method, without the use of chemical crosslinkers. Here, the individual biomaterial components used in this research were tested for their inherent antibacterial properties while determining the minimum inhibitory concentration of each constituent biomaterial. A modified physical crosslinking method was used to fabricate a hydrogel biocomposite comprising CTS, CMC, and zinc-coated HNT. The physical characteristics of the hydrogel were assessed via rheological studies. SEM and digital microscopy were used to observe zinc-coated halloysites and the character of the hydrogel produced. Additional characterization tests carried out in this study include Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis, x-ray fluorescence, and x-ray diffraction (XRD). The results showed that zinc doped HNTs, when loaded with a low dose of gentamicin sulfate, stagnated the growth of gram-positive and gram-negative bacteria for extended hours, suggesting the possibility of less dependence on the use of antibiotics. The results also demonstrate the feasibility of fabricating a CTS/CMC polymer conjugate via a simple physical crosslinking method devoid of harsh crosslinking chemical agents. The second project involved in vitro assessment of the effect of the fabricated chitosan-based composite on wound closure and cell migration. These properties were evaluated via in vitro assays, including proliferation and live/dead assays for cytotoxicity assessment, antimicrobial tests, alizarin red staining and scratch assay. The results suggested that the chitosan polymer conjugate had improved functionalities of biocompatibility, non-toxicity, and antimicrobial properties against gram-positive and gram-negative bacteria. In addition, the fabricated chitosan/CMC composite also showed an improved cell migration effect on human skin dermal fibroblast. This result suggests that the chitosan-based fabricated conjugate could serve as a new promising candidate for wound healing applications. In a closely related third study, the use of solvent casting method to fabricate CTS/CMC film membranes bearing added functionality for biomedical applications is reported. Material characterization tests were carried out to confirm the presence of the constituted biomaterials. The tests include microscopy imaging and SEM analysis to determine the physical and surface topography of the fabricated biomaterial. Additional tests carried out include, thermogravimetric analysis (TGA), tensile strength, cell proliferation, cytotoxicity (live/dead), and antibacterial studies. The results of this project showed that the prepared biomaterial was relatively hydrophobic and non-toxic with improved thermal stability. Additional tests will be performed in future studies to obtain the ideal film membrane

    Chapter 34 - Biocompatibility of nanocellulose: Emerging biomedical applications

    Get PDF
    Nanocellulose already proved to be a highly relevant material for biomedical applications, ensued by its outstanding mechanical properties and, more importantly, its biocompatibility. Nevertheless, despite their previous intensive research, a notable number of emerging applications are still being developed. Interestingly, this drive is not solely based on the nanocellulose features, but also heavily dependent on sustainability. The three core nanocelluloses encompass cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), and bacterial nanocellulose (BNC). All these different types of nanocellulose display highly interesting biomedical properties per se, after modification and when used in composite formulations. Novel applications that use nanocellulose includewell-known areas, namely, wound dressings, implants, indwelling medical devices, scaffolds, and novel printed scaffolds. Their cytotoxicity and biocompatibility using recent methodologies are thoroughly analyzed to reinforce their near future applicability. By analyzing the pristine core nanocellulose, none display cytotoxicity. However, CNF has the highest potential to fail long-term biocompatibility since it tends to trigger inflammation. On the other hand, neverdried BNC displays a remarkable biocompatibility. Despite this, all nanocelluloses clearly represent a flag bearer of future superior biomaterials, being elite materials in the urgent replacement of our petrochemical dependence

    Biomatériaux dérivés d’une matrice extracellulaire (MEC) pour l’ingénierie tissulaire et les dispositifs médicaux

    Get PDF
    Abstract: Tissue engineering involves the production of whole organ or a part of it in vitro or in vivo. Decellularized organs as scaffolds for reconstructing organs have been emerging due to the potential of the ExtraCellular Matrix (ECM). ECM is a complex structure primarily composed of proteins and glycosaminoglycans (GAGs). Most common proteins include collagens, laminins, fibronectins and elastins. Several commercial products have been derived from ECM including tissue papers, 3D-printed scaffolds, and wound dressings. Bioadhesives are currently employed alone or as adjuncts to sutures to seal leaks of air or blood from organs following surgical interventions. ECM-incorporated bioadhesives could be hypothesized to not only seal leaks, but also to regenerate tissues. This thesis aims to investigate the composition and properties of ECMs derived from different porcine organs (bladders, kidneys, livers, lungs, and pancreas) using detergent-based and detergent-free methods. The first experimental work includes the design of a cell culture system to study the effect of detergent-based and detergent-free decellularized bladders on insulin-secreting rat pancreatic cell (INS-1) proliferation and functionality. ECMs were characterized initially for conservation of ultrastructure and removal of dsDNA. CyQUANT proliferation assay indicated cell proliferation following 7 days of culture on detergent-free decellularized bladders. Glucose-stimulated insulin secretion (GSIS) and immunostaining confirmed that cells were functional. The second experimental work involved decellularization of the five porcine organs using the detergent-based and detergent-free methods. Two additional steps were added to the detergent-free approach (pH adjustment and ethylenediaminetetraacetic acid (EDTA) treatment) to aid in the removal of residual hemoglobin from the organs. ECMs were characterized by staining for the removal of cellular content and conservation of ultrastructure. Further, mass spectrometry revealed better conservation of a greater number of key proteins such as collagen IV, laminins, fibronectin, and elastin in the ECM resulting from the detergent-free methods, as compared to that produced using the detergent-based one. Collagen fibers orientation measurement indicated preservation of the fibers orientation in the ECMs as compared to that measured in the native organs. The third experimental work initially screened the INS-1 cell response on different organ ECMs. INS-1 cells were functional on certain detergent-free decellularized organs following 7 days of cell culture. Finally, mouse primary pancreatic islets were seeded on the detergent-free decellularized bladders, revealing functional islets following 48 hours of culture.Le génie tissulaire consiste à construire un organe entier ou une partie de celui-ci in vitro ou in vivo. Les organes décellularisés utilisés comme échafaudages pour la reconstruction d'organes sont de plus en plus populaires en raison, entre autres, du potentiel de la matrice extracellulaire (MEC). La MEC consiste en un ensemble complexe composé principalement de protéines et de glycosaminoglycanes (GAG). Les protéines les plus courantes comprennent les collagènes, les laminines, les fibronectines et l’élastine. Plusieurs produits commerciaux sont composés de MEC, notamment des papiers tissulaires, des encres pour l’impression 3D et des pansements pour le traitement de plaies. Les bio-adhésifs sont actuellement utilisés seuls ou en complément des sutures pour sceller les fuites d'air ou de sang à la suite d’interventions chirurgicales. On pourrait supposer, par exemple, qu’un bio-adhésif incorporant la MEC permettrait non seulement de sceller une fuite, mais qu'il contribuerait également à la régénération tissulaire. Cette thèse a pour objectif général d’évaluer la composition et les propriétés de la MEC dérivée de différents organes porcins (vessie, rein, foie, poumon et pancréas) décellularisés à l'aide de méthodes utilisant un détergent et sans détergent. Également, le projet vise à développer une nouvelle famille de biomatériaux à base de MEC pour des applications en médecine. Le premier travail expérimental comprend la conception d'un système de culture cellulaire pour étudier l'effet des vessies décellularisées, avec ou sans détergent, sur la prolifération et la fonctionnalité des cellules pancréatiques (INS-1 cellules) de rat sécrétant de l'insuline en réponse à des gradients de glucose. Les MECs ont été initialement caractérisées pour la conservation de l'ultrastructure et l'élimination de l'ADN double brin. L'analyse utilisant un test de prolifération CyQUANT a indiqué une prolifération cellulaire après 7 jours de culture sur les vessies décellularisées sans détergent. La sécrétion d'insuline stimulée par le glucose (GSIS) et l'immunomarquage ont confirmé que les cellules étaient également fonctionnelles. Le deuxième travail expérimental visait la décellularisation des cinq organes porcins à l'aide d’une méthode utilisant un détergent et de méthodes sans détergent. Deux étapes supplémentaires ont été ajoutées à la technique sans détergent (ajustement du pH et traitement par éthylènediaminetétraacétate (EDTA)) afin de réduire la présence d'hémoglobine résiduelle dans les organes décellularisés. Les MECs ont été caractérisées en histologie par différentes colorations pour investiguer l'élimination du contenu cellulaire et la conservation de l'ultrastructure. De plus, la spectrométrie de masse a révélé la conservation d'un plus grand nombre de protéines clés telles que le collagène IV, les laminines, la fibronectine et l'élastine dans les MECs produites avec des méthodes sans détergent par rapport à celles résultantes de la méthode utilisant un détergent. Les mesures de l’orientation du collagène ont indiqué une conservation de l'orientation dans les MECs par rapport à la structure native. Le troisième travail expérimental a initialement investigué la réponse des cellules INS-1 exposées aux différentes MEC d'organes. Les cellules INS-1 demeuraient fonctionnelles sur certains organes décellularisés sans détergent après 7 jours de culture. Enfin, des îlots pancréatiques primaires de souris ont été ensemencés sur des vessies décellularisées sans détergent, révélant ainsi que les îlots étaient fonctionnels après 48 heures de culture

    Native American Medicine

    Get PDF
    Openly licensed anthology focused on the theme of Native American medicine. Contains: Ethnobotany of the Ojibwe Indians by Huron H. Smith; The Botanical Lore of the California Indians by John Bruno Romero; The Sacred Formulas of the Cherokees by James Mooney; The Medicine-Men of the Apache by John Gregory Bourke; The Mide\u27wiwin or Grand Medicine Society of the Ojibwa by Walter James Hoffman

    Cellulose based aerogel microfibers for biomedical applications

    Get PDF

    Skin Grafts for Successful Wound Closure

    Get PDF
    Wounds with full thickness or deep partial thickness skin loss require skin grafts to achieve closure and minimize functional and aesthetic effects of healing. This book presents a comprehensive overview of skin grafts for wound closure. Section I includes three chapters that discuss established methods of wound bed preparation as well as new agents and methods. Section II includes three chapters that provide basic information about skin grafts and grafting procedure techniques
    • …
    corecore