Challenge Journal Publications (TULPAR Academic Publishing)
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What should we do to ameliorate the quality of interfascial plane blocks? Is dual block the answer sought or a waste of effort?
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The effect of the gravity on the earthquake performance of roller compacted concrete dams
Full text linkRoller compacted concrete (RCC) is a dry concrete mixture often utilized in the construction of large dams. The interlayer of the RCC dam, which is the weakest plane of the structure, can easily fail under hydraulic shear load, geological impact, earthquake force and environmental impact. In this study linear and performance analyzes were carried out for eight different scenarios for foundation effect, gravity effect and empty and full reservoir situations. In analyses, the earthquake response and performance of the Akçakoca RCC Dam, taking into account the interaction between the dam and the water. The reservoir water behavior is simulated using the Eulerian-Lagrangian coupled (CEL) approach with finite elements modeling. Linear analyses reveal that hydrodynamic pressure leads to increased displacements and principal stresses. The earthquake performance evaluation of the Akçakoca RCC dam indicates that critical concrete damages are expected based on linear time-history analyses conducted for both empty and full reservoir scenarios. Besides, according to this study, gravity effect clearly increases the earthquake performance of the dam
How does intravenous ondansetron affect motor and sensory block in spinal anesthesia administered with intrathecal levobupivacaine? A prospective randomized controlled study
Full text linkBackground: Spinal anesthesia is commonly performed in surgical procedures, and ondansetron, frequently used as an antiemetic, is often administered to manage postoperative nausea and vomiting. Given their frequent co-administration, we sought to investigate the potential effects of intravenous ondansetron on the block characteristics of spinal anesthesia performed with levobupivacaine.Materials and Method: In this prospective, randomized controlled study, forty patients were divided into two groups: Group L (spinal anesthesia with levobupivacaine) and Group OL (spinal anesthesia with levobupivacaine plus intravenous ondansetron).Results: Our findings showed that while motor block duration was similar between the groups (p>0.05), sensory block duration was significantly shorter in the ondansetron group (p0.05).Conclusions: The shortened sensory block with ondansetron administration may be clinically undesirable as it could limit the intended duration of anesthesia. We recommend administering ondansetron at the end of surgery to avoid this effect. Further studies are required to confirm these findings and clarify the mechanisms involved
Perioperative ventricular dysrhythmia management in ranula cyst excision surgery
Full text linkRanula cyst is one of the most common pathologies of the sublingual salivary gland. It is formed as a result of damage to the gland ducts and is a retention cyst filled with mucus. Methods such as drainage, excision or cryosurgery are used in the treatment. During surgical treatment, it may cause various dysrhythmias due to its anatomical relationship with the vagus nerve. In this study, we aimed to present our response to arrhythmias seen during ranula cyst excision and resistant to IV administration with local lidocaine administration
Comparison of the analgesic effects of different bupivacaine concentrations in continuous femoral block after total knee arthroplasty surgery
Full text linkAim: In regional anesthesia practice, anesthesists’ goal must be to use the lowest effective concentration of local anesthetics to provide sufficient pain relief while minimizing side effects and complications. This study was designed to compare the analgesic efficacy of two different concentrations of bupivacaine (0.125% and 0.1%) in continuous femoral block for postoperative analgesia.Method: In this study, fifty patients were enrolled, all of whom underwent femoral nerve block catheterization. The block procedure involved the administration of 30ml of bupivacaine solution at a concentration of 0.25%. Following a thirty-minute interval post-block application, patients underwent knee surgery under general anesthesia. During the closure of subcutaneous tissues, an additional 10ml of bupivacaine solution was injected through the catheter. Two groups were formed based on the concentration of the solution administered: Group(0.125%) received bupivacaine at a concentration of 0.125%, while Group(0.1%) received it at a concentration of 0.1%. Subsequently, upon arrival at the postoperative care unit, infusion through the catheter commenced at a rate of 10ml/h-1, maintaining the same concentrations for both groups. In addition to the nerve block, all patients were provided with intravenous Patient Controlled Analgesia (PCA) devices containing morphine for pain management. Throughout the postoperative period, sensory and motor block levels, Numerical Rating Scale (NRS) values for static and dynamic pain assessment, total morphine consumption, morphine demand, as well as any observed side effects and complications, were meticulously recorded for analysis.Results: Postoperatively the NRSstatic values at 24th and 48th hours and NRSdynamic values at the 24th hour were higher in Group(0.1%) and it was statistically significant(p<0,007). And at 48th hour, morphine consumption was significantly higher in Group(0.1%) (p<0,05).Conclusions: In our study, all patients across both experimental groups initially experienced satisfactory analgesia. However, within the 24-hour postoperative period, Group(0.1%) exhibited a decline in the quality of analgesia, necessitating increased utilization of rescue analgesics. This escalation in rescue analgesic use was associated with a higher incidence of adverse effects and reduced patient comfort levels within this group. Consequently, our findings indicate that the 0.125% concentration of bupivacaine yielded superior efficacy compared to the 0.1% concentration in the context of continuous femoral block administration
Optimization of mechanical properties in lime-based composites using the Taguchi method
Full text linkGlobal warming is widely recognized as one of the most pressing issues of our time. One of the primary contributors to this phenomenon is the emission of CO2, which significantly exacerbates global warming. Today, the production and industry of cement stand out as leading sources of carbon emissions. Consequently, the scientific community is actively researching solutions to reduce cement usage. Some of these efforts focus on alternative binders such as silica fumes and lime. In this study, the goal is to enhance silica fume and lime binder composites, optimizing them for both refractory and insulating properties using the Taguchi optimization method. The results indicate significant improvements in compressive and flexural strengths, which were further validated through testing. The highest compressive strength achieved was 11.97 MPa, while the maximum flexural strength reached 0.34 MPa. This research underscores the potential of alternative binders in mitigating the environmental impact of cement production while enhancing material performance in various applications
The effect of build direction on component strength in SLA-based additive manufacturing
Full text linkNowadays additive manufacturing is frequently used, especially in industrial applications such as aerospace and biomedical. In the additive manufacturing method, thanks to the layered manufacturing technique, it enables the production of components with all kinds of complex geometries and accelerates the production process. As it is known, the orientation of the layers in the additive manufacturing technique affects the mechanical properties of the components. Among the parameters affecting strength, layer thickness, production direction and layer geometry are of great importance. In this study, the effect of layer orientation on component strength in SLA-based additive manufacturing was experimentally investigated. Consequently, standard tensile samples were produced at four different production orientation using the UV Stereolithography method. Tests of the tensile samples were carried out at constant tensile speed and tensile curves were obtained. According to the results, it was determined that the layer joints parallel to the shear plane exhibited the lowest strength. Therefore, samples produced at the parallel to the shear plane fractures at lower loads and showed low strength. Considering the experimental results obtained, it has been determined that the structure orientation affects the mechanical properties of the component by ~20%