Needle Stick Injuries (NSIs) are a significant occupational hazard for healthcare workers, exposing them to life-threatening pathogens such as HIV and Hepatitis B and C. Although safety-engineered devices have successfully reduced NSI rates in high-income countries, their high costs, limited adaptability, and environmental impact hinder their adoption in low- and middle-income countries.

This thesis addresses the need for a cost-effective, sustainable, and user-friendly needle safety system applicable to low- and middle-income countries, particularly in Nepal. The objective is to explore the solution space and propose an optimal blueprint for a needle safety system for this context, in order to provide the foundation for a novel needle safety system.

To achieve this, multiple design phases and a field trip are performed. The exploration of the solution space is guided through the elimination by aspects decision-making strategy through multiple design phases. The first started with conceptual strategies ought to solve the composed design brief; the remaining two strategies were translated into concepts that were ultimately developed into MVPs. Within this process, concepts were discontinued on the basis of the elimination by aspects method. This resulted in one efficient strategy. From this process, two effective devices employing the strategy are identified.

Validation trials in six Nepali hospitals demonstrated their effectiveness, usability, and acceptance among healthcare workers, emphasizing their potential to address the challenges faced. In addition, the field trip validated the problem analyses and underscored the need for such solutions. Both systems can meet the design requirements described and perform well in the performance metrics. The concepts provide a foundation for future development, marking a step toward safer, more affordable, and sustainable needle practices.

Future research should explore the market need for the proposed one-handed and handheld solutions. Finally, the proposed solutions can be optimized to lower force requirements and must be refined for large-scale production and ensure compliance with medical standards.

background: To decrease health care’s emissions, the reacquiring of rare earth metals from a complex single use medical device was researched. For a complex single use device (SUD), a cardiac catheter was used, which has electrodes in its tip made of platinum, iridium and palladium. methods: A patent study was done to gain insight into the design and assembly of the catheters, which resulted in the identification of the plastics present. Depending on the electrode type, polyether etherketone (PEEK) or polyamide 12 (PA12) were dominant plastics surrounding the electrode. 5 concepts were developed, all involving a chemical or thermal treatment, which were assessed on their ability to structurally remove these plastics. The treatments used were: nitric acid treatment, sulphuric acid treatment, pyrolysis treatment, toluene treatment and phenol treatment. Treatment removal ability and the purity of the acquired electrodes, were assessed through the use of mass fractions and SEM analyses. Practical aspects, which will be relevant for scale up, such as risk indications, waste created and costs were briefly assessed as well. results: The only treatment that was able to structurally remove all plastics without compromising electrode’s purity, was the sulphuric acid treatment. It is in line with literature that sulphuric acid is the only agent able to structurally remove PEEK at room temperature. Pyrolysis could remove the plastics, but the electrodes were charred. Nitric acid and phenol could only dissolve PA12 but left PEEK structurally present, whereas toluene left all plastics structurally present. conclusion: Reacquiring the electrodes chemically is possible through the use of sulphuric acid. If the spent sulphuric acid can be regenerated, this would be a great benefit since no constant replenishment of acid is required. Pyrolysis could also be investigated further, but a separate cleaning step would be required.

Each year in the Netherlands almost two thousand people are diagnosed with End Stage Kidney Disease, amounting to a total of 7 million people worldwide. With an insufficient amount of donors available, most of these patients are treated using haemodialysis where the blood is filtered with a dialysis machine. Prior to this treatment an arteriovenous fistula (AVF) or arteriovenous graft(AVG) is created to increase their blood flow sufficiently to speed up the filtration process. Another result of increasing the blood flow is the size increase of the vein, leading to easier access. Unfortunately, the continuous high flow rate is linked to various negative effects. To counter these negative effects a Dynamic Arteriovenous System (DAS) or dynamic AVF (dAVF) was developed that can regulate the flow on demand. This allows for the flow to be increased temporarily during dialysis and to return to nominal values outside of dialysis with the ultimate goal of increasing life expectancy. Earlier iterations of the dAVF encountered reliability issues due to the formation of fibrous tissue on critical locations of the implant hindering actuation on the anastomosis. For this project, a compliant implantable dAVF-Valve is developed that minimizes the influence of ingrowth and provides a more robust solution.

Introduction- The global incidence of thyroid cancer has risen significantly, prompting the development of innovative surgical techniques. Transoral thyroidectomy offers a scarless alternative, with the transoral endoscopic thyroidectomy vestibular approach (TOETVA) showing promising results. However, CO2 insufflation during TOETVA can lead to fatal complications. To address these issues, researchers have explored gasless TOETVA methods. Our study introduces a modular articulating retractor integrated with a 5mm camera system, aimed at minimizing CO2-related complications while preserving the benefits of the conventional procedure.
Method- Through a design process comprising problem definition, ideation, and solution creation. A detailed digital CAD design is developed based on force measurements obtained from a preliminary cadaver study. Subsequently, a functional prototype is created and subjected to pre-clinical testing using Thiel-embalmed and fresh frozen cadavers.
Result- Force tests determined a mean force of 4.73N across cadavers, with 5.29N necessary for optimal skin elevation. SolidWorks simulation indicated maximum stresses of 128.10 MPa and 113.80 MPa in articulated and horizontal positions. Backdrivability of articulation occurred at approximately 4N applied force. Assembly and disassembly tasks demonstrated mostly normal distribution, with significant differences observed between initial and final assembly attempts. Despite successful procedure performance, challenges included endoscope removal limitations and partial functionality constraints during articulation within cadavers. Overall removal time averaged 3.2s, with a maximum of 4.1s.
Conclusion- The gasless TOETVA procedure was performed successfully with sufficient visualization for the surgeon. While achieving three of our four objectives, including the design and compatibility with standard endoscopic cameras, limitations prevented direct comparison with conventional CO2-based TOETVA methods. Despite this setback, the initial incorporation of our instrument into surgical procedures demonstrates promise. However, further research is imperative to compare its performance against conventional methods, validating its efficacy and potential in clinical practice.

Background: Laparoscopic surgery has improved patient outcomes and reduced healthcare costs in high-income countries but faces implementation barriers in low -and middle-income countries due to reliance on carbon dioxide insufflation, expensive equipment, and specialized personnel. Gas Insufflation-Less Laparoscopic Surgery (GILLS) provides an alternative by lifting the abdominal wall without carbon dioxide; however, expensive laparoscopes and assisting staff to operate those remain necessary. Hence, the need for a device that substitutes for the gas insufflation and laparoscope was identified.

Methods: This thesis aimed to integrate an abdominal wall lift (AWL) device and imaging system to enhance GILLS and Single-Incision Laparoscopic Surgery (SILS). Using a context-driven approach, the design focused on surgeon visibility, patient safety, cost-effectiveness, and user-friendliness. The device was developed using inexpensive, readily available components and conventional production techniques. The validation included seven verification tests and an expert user evaluation.

Results: The lifting device consists of a stainless steel tubular hook with LED lighting and a $5$ MP camera module. It can be inserted in the abdomen through a small incision, lifts the abdominal wall, and creates a clear view inside the abdominopelvic cavity. An aluminum prototype had sufficient structural strength, was cost-effective, lightweight, and compatible with existing AWL systems, but it generated excessive heat, was not waterproof, and lacked a functional imaging system. Evaluation by a GILLS expert highlighted design strengths while emphasizing three areas for improvement: the frame's shape, the imaging system, and the sealing technique.

Conclusion: This study illustrated the potential of integrating an abdominal wall lift device and imaging system despite the substantial constraints of the current tubular design. The cost-effective alternative eliminates the reliance on carbon dioxide gas, expensive laparoscopes, general anesthesia, and untrained assisting staff. Therefore, development should continue to improve access to laparoscopic surgery worldwide.

Introduction - Surgical robotic systems are increasingly valued for their precision and benefits to patients and surgeons, yet traditional designs rely on costly, limited-use, cable-driven instruments that require frequent replacement and specialised cleaning equipment. To address these issues, the Sustainable Surgery & Translational Technology group MI & BITE developed the Advanced Laparoscopy Robotic System (AdLap-RS) with modular shaft-actuated tip articulation (SATA) instruments. Their modular design allows for disassembly, easy cleaning, and part replacement, enhancing reuse potential and lowering operational costs. With the substantial environmental impact of surgical activities, reusable SATA instruments also offer promising sustainability benefits. However, inconsistencies in life cycle assessments (LCAs) applied within the surgical field raise concerns about their reliability, complicating accurate environmental assessments of this innovative technology.
Goal - This research aims to assess the environmental impact of the reusable SATA instrument technology for robotic surgery through a robust comparative LCA while simultaneously informing sustainable design choices during the SATA instrument technology’s ongoing development.
Method - The initial phase of this research included a literature review and a survey among European Association of Endoscopic Surgery (EAES) members to identify reliability challenges in applying LCAs to surgical instruments. Insights from this phase informed a robust comparative LCA, assessing the environmental footprint of one of the reusable SATA instruments against its traditional limited-use counterpart, which also functioned as an eco-design evaluation by applying a circular eco-design approach.
Results - Findings from the first part showed a significant gap in LCA usage in surgical decision-making, largely due to limited familiarity and trust in LCA findings. The absence of a standardised, user-friendly LCA methodology tailored to the complexities of surgical instruments further complicates accurate assessments in this specialised domain. Comparative LCA results revealed that the reusable SATA instrument reduces climate change and energy impacts by over 50% compared to its limited-use counterpart. For both instruments, the use phase represented the largest contributor to environmental impact, primarily due to the energy-intensive disinfection and sterilisation cycles required before each reuse. The eco-design evaluation recommends prioritising modularity and disassembly improvements to optimise tray load capacity and reduce reprocessing impacts.
Conclusion - While this study robustly indicates the sustainability benefits of the innovative reusable SATA instrument technology for robotic surgery, capturing the full complexity of surgical instruments in LCAs remains challenging. Addressing this will require stakeholder engagement, targeted LCA training, refined LCA methodologies, and comprehensive review processes tailored to this specialised field.

Laparoscopic surgery is the golden standard in minimal invasive surgery. But even though it only has a rare occasion of giving complications, about 70% of major complications happen during the first entry of the body. The two most commonly used entry methods are the Hasson open method, and the Veress Needle closed method. A recent development to the Veress Needle was found to be much safer in clinical studies by automatically decoupling the user when they pass through the parietal peritoneum, yet still has room for development. The main focus of this resides in enhancing the decoupling mechanism to be less vulnerable to its user. This will be achieved by shielding off the critical parts during operation and by guiding the user during the reloading to prevent damage to the device. These goals are divided into subproblems, and individual solutions are found. Based on the previous solutions several concepts are created and the most promising one chosen for prototyping and testing. After several iterations using rapid prototyping using 3D printing a final prototype was made from stainless steel. This final prototype was then used to execute a series of tests using ten participants which used the device for 99 times in total. During these tests the device was tested on reloadability and its transition between its three phases. Each participant also filled in a five-point Likert scale questionnaire and gave open feedback on their desired changes to the device. The testing of the prototype showed it was easily reloadable and had a phase transition success rate of 62.6% between phase one and two and 59.7% between phase two and three Based on these results it was found that the transition between the real design and the prototype was done unsuccessful, several areas of improvement where identified as a result of the testing but no guarantee was found that the new system could equal or surpass the reliability of the Veress Plus.

This thesis project is part of a larger research project at the LUMC and focuses on overcoming challenges in studying blood vessel mechanics, particularly disturbed flow conditions, using Gelatin Methacryloyl (GelMA). Traditional models fail to replicate the complexity of blood vessels. GelMA stands out for its adjustable mechanical properties, such as stiffness and elasticity, closely mimicking natural blood vessels. It supports cell growth, which is vital for modelling blood vessels realistically. The current gap in research lies in the accurate representation of the mechanical environment of blood vessels, limiting our understanding of vascular diseases like atherosclerosis. Improvements are needed in flow models to replicate natural blood flow patterns and conditions such as bypasses or arteriovenous fistulas more accurately.
Goal
The development and validation of an improved GelMA disturbed flow model for in vitro validation of cell culturing under disturbed flow conditions.
Method
To determine the compressive modulus of the GelMA, three sets of samples are produced with different exposure times to UV light. These samples were subjected to compressive testing to determine the pressure/strain characteristics of the GelMA.
Furthermore, the disturbed flow model is partially newly designed. A new cover allows for incorporating a pressure sensor to determine if the model can operate under physiological pressure levels. To achieve this pressure, a pump with adjustable flow output is selected. Flowmeters were included in the test setup to determine when the correct flow was performed. The balance between the right pressure and flow results is described as the systemic vascular resistance of the disturbed flow model.
Results
The results of this study are the findings on the compressive modulus of the GelMA used for the research in the LUMC. The optimal curing time for achieving 10\%-15\% strain at physiological pressure levels (80-120 mmHg) was identified as 150 seconds, indicating a clear relationship between curing duration and GelMA's mechanical properties. The disturbed flow model improved the mean pressure to 113 mmHg, showing a more consistent pattern but with systolic pressure exceeding the desired range. Placing the sensor directly on the disturbed flow model improved results, suggesting potential improvements over the current IBIDI pump system waveform. The experiment targeted a total flow of 12 ml/min, similar to earlier experiments. It prevented cells from washing away from the GelMA substrate, with a split between inlets and outlets of 15\%-85\%. Initial runs used syringes for flow measurement, achieving a total flow of 11.8 ml/min, with a split of 1.8 ml/min and 10 ml/min, matching the desired split. With a pressure of 113 mmHg and total flow of 11.8 ml/min, the calculated total system resistance is 9.58 mmHg*min*mL-1 Peripheral Resistance Units (PRU), equivalent to 766 dynes*sec*cm-5 in cgs units.
Conclusion
This project successfully determined GelMA's possibilities in creating advanced in vitro vascular models, particularly under disturbed flow conditions. Through experimentation, GelMA demonstrated the ability to mimic native blood vessels' mechanical properties, offering improvements for future vascular research. Optimal conditions for GelMA were identified with a curing time of 150 seconds, resulting in a strain of 10\%-15\% under physiological pressures (80-120 mmHg). The fluidic test setup closely approached physiological pressures and allowed for two pathways resembling arteriovenous fistula (AVF) or bypass conditions. The correct flow of 12 ml/min and a split of 15\%-85\% was achieved. Determining systemic vascular resistance (SVR) contributes to setting up future experiments quicker and accurately within desired parameters.

The sterile packaging of instrument trays containing medical devices is a critical step in the sterilization process for various medical and industrial applications. This process involves wrapping instrument trays with nonwoven polypropylene sterilization wrap, which plays a crucial role during and after sterilization. Traditionally, the loose ends of the wrap are secured using autoclave tape. However, the presence of this tape poses a risk of recycling contamination when the wraps are disposed of for recycling. Additionally, in some cases, the autoclave tape has been found burnt at the end of sterilization due to excessive use during the packaging process. This study aims to design and develop a prototype sealing device that eliminates the need for autoclave tapes while maintaining the integrity of the sterile barrier system. During this study, two prototypes of sealing devices were developed: one utilizing ultrasonic sealing technology and the other using impulse sealing technology. The ultrasonic sealer is sourced from a cold-fusion sealer, while the impulse sealer is obtained from a plastic packaging device. Both devices are upgraded and repurposed as per the drawn-up requirement specifications and development criteria. To validate the prototypes, a product characterization test is conducted optimizing the seal time settings based on seal strength tests following ASTM F88/F88M-21. The optimum seal strength, measured using the T-peel test, is determined to be 1.21±0.05 N/mm for the impulse sealer and 0.93±0.08 N/mm for the ultrasonic sealer at the optimized seal time for a test sample width of 30 mm. This is succeeded by, a demonstration of the prototypes at Maastad CSA in Rotterdam, assessing the usability and functionality of these devices. During the demonstration sealed sterile packages were made following a standard envelope-wrapping approach. Replacing autoclave tapes with the seals at the critical points to secure the wrap. Feedback is collected from employees regarding the new method of packaging. Two sealed sterilization packages produced following the use of both prototypes are subjected to a trial run in an autoclave for sterilization testing. The seals proved to be effective in withstanding the sterilization process without compromising the package's integrity.
The results of this study contribute to sustainability efforts in the healthcare sector by offering a more efficient and environmentally friendly approach to maintaining the sterility of reusable medical devices.

Annually, around 180,000 cardiac ablation procedures are performed as a result of people experiencing cardiac arrhythmia’s. During this ablation procedure, an ablation catheter is used to scar the problematic cardiac tissue after which the arrhythmia will stop. The ablation catheter is discarded after one single use. Incineration of these ablation catheters not only means destruction of valuable product, but also additional carbon emissions and pollution. The goal of this research is to design a novel disassembly method for the Thermocool Smarttouch SF Uni-directional Catheter (TAC) to enable extraction of the most yielding parts and/or materials. By means of a Hotspot Map and a part-specific cost estimation the most yielding parts (or PoIs) of the TAC were determined to be the shell, the ring electrodes and the electronics unit. The novel disassembly method was designed with those PoIs in mind and consists of two separate entities: a disassembly prototype (designed to enable extraction of the determined PoIs) and an ultrasonic cleaning stage (to further purify the extracted PoIs). The novel disassembly method was validated and indeed proved to be extracting the PoIs in a more successful, pure, and reasonably timely way compared to a previously performed rough disassembly. Therefore, the outcome of project is successful. However, a critical note must be introduced. Sustainability-wise the outcome is promising, however, from a business standpoint this could be more difficult. Almost all extracted PoIs will be damaged to some extent, and rules say only virgin materials can be used for the development of new catheters: only the costs of the extracted raw material will be yielded. All value added during the manufacturing stage is lost. Taking into account the additional costs of disinfection, shipping, labour and further reprocessing methods, this novel disassembly method would possibly cost more than it would recover. Other opportunities like multiple uses, detachable (sub)assemblies or alternative business cases should be explored.

With increasing healthcare demand, environmental concerns and waste management in healthcare, particularly in the operating room (OR), are significant issues. Disposable surgical energy devices, like vessel sealers, gain popularity in veterinary healthcare, but reusing them is officially forbidden by law and presents challenges. Objective: This research aims to clinically validate reprocessing the Ethicon HARMONIC® HD 1000i for safe reuse in veterinary healthcare. The study assesses the feasibility of using readily available disinfection methods and evaluates the device’s functionality and safety. The research’s scope is limited to a case study (functional analysis) on the Ethicon HARMONIC® HD 1000i. Methods: A comprehensive device analysis was performed using Hot Spot Mapping and Disassembly Map methods, followed by mechanical stability testing during sterilization conditions. A design update was proposed for easier disassembly. The functionality of 2x new, 2x reprocessed and 2x redesigned Ethicon HARMONIC® HD 1000i’s after reprocessing (disinfection, disassembly, reassembly, sterilization) was evaluated in a bench-top study. Tissue transsections on 120 cm pork fillets (6-11mm thickness) per device and pinch force measured with newly developed sensor (40 movements/device) were performed. Furthermore, 2 burst pressure measurements per device on frozen and embalmed artery sections were performed in collaboration with Amsterdam Skills Centre for Health Science. Results: In the disassembly analysis, 42 operations were needed, involving 40 parts and 10 steps with 6 tools. The disassembly time was 429 seconds (07:09 minutes) total. In tissue transsection, the new and reprocessed devices performed similarly, with mean task times ranging from 62.3 to 66.8 seconds. The redesigned devices had slower task times (averaging 196.1 seconds and 104.7 seconds) resulting in lower marching speeds (0.5-1.0 mm/s compared to 1.5-1.6 mm/s for new and reprocessed devices). In pinch force measurements the new devices performed best with average pinch forces of 19.1 N and 20.2 N. The reprocessed devices had slightly lower performance (16.8 N and 16.7 N), while the redesigned devices performed the worst with pinch forces of 5.6 N and 8.8 N, representing a significant drop in performance compared to the new devices. The burst pressure measurement tests showed that none of the devices were able to effectively seal the arteries, resulting in no pressure buildup. Discussion: Overall, reprocessed devices performed similarly to new devices in tissue transsection, showing the effectiveness of reprocessing. Achieved marching speeds by reprocessed and redesigned were considerable given tissue thickness differences, highlighting reprocessing’s potential to extend device lifespan. New devices had 15% higher pinch force than reprocessed, while redesigned had 63% lower force due to a weakened casing. Strengthening redesign and adding new jaw ends could improve modularity and power transmission. Burst pressure tests revealed all Ethicon Harmonic devices (new, reprocessed, redesigned) couldn’t effectively seal
arteries, likely due to frozen artery characteristics and tissue alterations from embalming. Conclusion: This study emphasized the potential of modular medical devices with improved disassembly time, demonstrating that a modular design approach combined with reprocessing strategies holds promise to ensure a more sustainable healthcare system. This research is a collaboration between the Technical University of Delft, Johnson & Johnson Netherlands and GreenCycl.
Keywords: ETHICON, harmonic, ENSEAL, Ligasure, ster- ilisation, reprocessing, medical instruments, healthcare, veterinary, redesign, modular, burst pressure, tissue transection, pinch force

Laparoscopic surgery uses small incisions and a camera for abdominal or pelvic operations, with benefits such as shorter recovery time and hospital stay. However, reduced surgeon hand-eye coordination and feedback can lead to excessive applied force and potential tissue damage. Haptic and visual feedback systems have been developed for laparoscopic surgery, and their benefits for various laparoscopic tasks have been demonstrated. Although force feedback systems have been extensively studied, there is a dearth of research on force limiting mechanisms in laparoscopic surgery. Nonetheless, incorporating force limiting mechanisms could help prevent complications caused by excessive applied force by the user. This paper presents the design, production and validation of a force limiting mechanism in a laparoscopic instrument, to prevent tissue damage due to excessive applied force by the surgeon. A design method was conducted, which comprised a functional analysis and a design process. Subsequently, a force limiting mechanism was designed and manufactured using various techniques. To validate the mechanical performance, the force in the forceps Fpinch and the force in the rod Frod of the laparoscopic instrument were measured. This was carried out under three conditions with the force limiting mechanism set at 10 N, 20 N, and 40 N for Fpinch. To validate pre-clinical performance, twenty novices performed a crossover study. Participants performed a basic laparoscopic task by grasping a Floral foam object under two conditions: with and without the force limiting mechanism. The relative depth and the slippages of the Floral foam object was computed after each trial. The mechanical validation results showed that for the instrument with the force limiting mechanism, Fpinch remained constant at 0.5 N and 2.0 N, while Frod increased. The pre-clinical validation revealed a significant difference in relative depth between the two instruments. The laparoscopic instrument with the force limiting mechanism was superior compared to the laparoscopic instrument without the force limiting mechanism (p<0.001), as less force was transferred by the force limiting mechanism. Additionally, no difference was found between the two instruments in slippages (p=0.068). It can be concluded that a force limiting mechanism in a laparoscopic instrument has been successfully designed and validated and can prevent tissue damage by blocking the excessive applied force by the surgeon. However, further improvement is required to overcome limitations in the design. Moreover, the design has to be tested in various (pre-)clinical settings in order to improve the validity and reliability of the design. Additionally, implementing the force limiting mechanism in robotic surgery should also be considered.

Background : Surgeons performing robotic-assisted laparoscopic surgery experience physical stress and overuse of shoulder muscles due to sub-optimal arm support during surgery. Following background literature research on passive
dynamic arm supports, this report presents and evaluates a novel design.
Objective: To present a novel design and prototype of a dynamic arm support for robotic laparoscopic surgery and evaluate the arm support for ergonomics and performance on the AdLab-RS simulation training device.
Method : The prototype was designed using the mechanical engineering design process: Technical requirements, concept creation, concept selection, 3D-design in Solidworks, built of the prototype. A crossover study was performed on participants divided into two groups, all performing a marble sorting task on the AdLab-RS. One group first performed four trials without the arm support, followed by four trials with the arm support, and the other group
vice versa. The performance parameters were time to complete (s), path length (mm), and the number of collisions. Afterward, the participants filled out a questionnaire on the ergonomic experience regarding both situations, including
part of the Nasa TLX questionnaire.
Results: A new arm support was developed and a total of 20 students took part in the study on its evaluation, which led to 160 performed trials on the AdLab-RS. Significant decreases in the subjective comfort parameters mental
demand, physical demand, effort and frustration were observed as a result of introducing the novel arm support. Significant decreases in the objective performance parameters path length and the number of collisions were also
observed during the tests.
Conclusion: The newly developed dynamic arm support was found to improve comfort and enhance performance through increased stability on the robotic surgery skills simulator AdLab-RS. However, the study’s limitations, such
as the short trial duration and non-surgeon participants, must be acknowledged when interpreting the results.

Background: Kidney failure, also called end-stage renal disease, means the kidney has lost its function to remove waste from the blood. Patients with kidney failure usually need hemodialysis, which uses a machine to replace the function of a healthy kidney, to keep them alive and prolong their lives. In order to begin hemodialysis, it is crucial to prepare vascular access, which is a location in your body from which blood can be drawn and then returned at a high rate. People have found that the traditional ways of achieving vascular access will lead to a series of complications. So the newly designed Dynamic Arteriovenous system (DAS), which can control the opening and closing of the arteriovenous graft, was designed to solve the problem. Since the DAS is implanted under the skin of the human arm, it is hard for the operator to observe the status of the graft, so a monitoring system that can detect the graft status is needed.Objective:The goal of the research is to deisgn and evaluate a monitoring system for detecting the graft status of the DAS.Method: To solve the research problem, four sub-questions are proposed and solved to achieve possible concepts for the design. A Harris profile with grading criteria is set up to compare and determine the final concept to be developed. After building a test set-up for the final design, the design's effective range, accuracy, size, mass, usability, and detection success rate are evaluated. Results: The final design of the monitoring system consists of three sensors outside the body and two magnets in the DAS. The three sensors react to the position change of the magnets in the DAS and determine the relative position of the DAS under the skin and the status of the graft with the help of a User Interaction Interface. Through in-vitro tests, it is evaluated that the design meets most of the requirements and can be further developed if proper components are chosen and in-vivo tests are done. Conclusion: A relatively complete concept of the monitoring system and the corresponding User Interaction Interface are designed. Through a series of tests, it is believed to have the potential to be further developed and be useful to the DAS. In-vivo tests must be done to evaluate the system's biocompatibility before the clinical appliance.

Abstract—Introduction: Surgical instruments are stored, transported, cleaned, disinfected, and sterilized in instrument sets. These instrument sets have a predetermined fixed size, which means they cannot be stored or transported efficiently when empty or used efficiently for different types of instruments. This report presents the design of an instrument set that is adaptable in shape for efficient storage and transport. Method: Based on a questionnaire completed by various departments that come into contact with instrument sets, such as the CSSD, logistics and repair and fixation, the context, the requirements and wishes of van Straten Medical. B.V. and CSA Services B.V., 15 requirements and criteria have been established. Five concepts were developed based on a morphological chart, after which a Harris profile showed that stacki is the best concept. Result: Stacki was further developed and designed using the 3D CAD software SolidWorks. 3 prototypes were created using water/laser cutting and 3D printing. To evaluate the prototypes and identify critical points, 3 tests were carried out regarding completion, ease of use, and strength. These tests have shown that the prototype is promising, but that the corner needs to be redesigned to make the prototype even better. Discussion: Of the requirements, 7 requirements have been met, and 6 requirements were not tested. For further research, these remaining requirements can be tested by applying the points of improvement. Conclusion: A prototype with perforations made from the final materials could be made and this new prototype could be tested for cleaning, disinfection, and sterilization. Finally, the idea with two half sides instead of one long side can also be further developed and tested. Overall, the instrument set is promising for further development, with this design as a starting point.

This paper addresses the urgent need to optimize the GreenCycl facilities energy utilization, by harnessing heat from the effluent of three thermal washing-disinfection machines into the preheating of cold clean water. Currently for every washing-disinfection cleaning program, 60 times a week, 105 liters of water with a temperature of 60 \degree Celsius is discharged in the drain. This is not in line with the goals setup by the government and the mindset of GreenCycl.

The study begins with a comprehensive analysis of the current situation, while documenting the properties and conditions. Subsequently concepts are generated with help of a morphological chart and a Harris profile is employed to select the most promising concept, this is further elaborated. Computational Fluid Dynamics (CFD) simulations are conducted to optimize the performance of the heat reclaiming system. Finally, the results of the CFD simulations are validated with experimental research.

By reintroducing 67\% of the effluent back into the heat exchange system, a continuous flow across the heat exchanger of 35 liters per minute can be established with an operation duration of 2.5 minutes per washing-disinfection machine. Resulting in the heat reclaiming system to only operate when cold clean water is flowing through the HEX. If implemented at the GreenCycl facility, this innovation could potentially save approximately 7600 kW of electrical energy and reduce Carbon Dioxide emission by 1129 kg annually.

This study not only addresses a pressing environmental concern but also offers an easy and efficient solution with significant economic and ecological benefits.

Achieving appropriate soft tissue tension around the hip joint is an important factor for achieving hip stability after Total Hip Arthroplasty (THA). Hip instability leads to dislocations, pain, and is a common reason for early revision surgery. The current soft tissue tension assessments available during surgery rely on experience, and dislocations occur twice as often after THAs performed by inexperienced surgeons compared to more experienced surgeons. This paper presents a new mechanism which measures and displays hip force in Three Degrees Of Freedom (3-DOF) during THA. A prototype measured axial and normal force components up to 75 N with a sampling frequency of 14.6 Hz, an accuracy up to 11 N, and a Root Mean Square Error (RMSE) of 4.0 N (axial) and 3.0 N (normal). Additionally, it measured the normal force direction with an accuracy up to 7.1∙10^(-2) π rad and RMSE of 7.1∙10^(-2) π rad. Data needs to be collected to build a predictive model which estimates the required hip force range and distribution to achieve a stable joint. When combined with such a predictive model, the proposed design is a promising assistive surgical tool.

Introduction: The environmental impact of singleuse medical plastics is a growing concern. One such plastic component, autoclave laminated plastic (ALP), commonly used in medical sterilization pouches, is typically discarded after use, but it holds potential for recycling. This research paper investigates the feasibility and effectiveness of mechanical recycling as a solution for ALP waste.
Methods: The study commences by analyzing the composition of collected ALP materials using X-ray diffraction analysis. Subsequently, recycling techniques,
including melting, and shredding, are explored and assessed.
Results: After multiple melting setups, the high-pressure melting setup, augmented by a continuous pressure spring mechanism, successfully yielded recycled ALP blocks that could be further processed into dogbone-shaped specimens. The results of the tensile tests revealed a Young’s modulus of 269 ± 85 MPa for the recycled ALP.
Discussion: These findings hold promise in the transformation of ALP waste into valuable recycled products, mitigating the environmental impact of single-use medical plastics. However, the study underscores the need for further optimization of the recycling process to enhance mechanical properties and overall material quality, ultimately advancing sustainability efforts in the medical sector.