Traditional manual testing of ventilator performance is labor-intensive, time-consuming, and prone to errors in data recording, making it difficult to meet the current demands for testing efficiency in the development and manufacturing of ventilators. Therefore, in this study we designed an automated testing system for essential performance parameters of ventilators. The system mainly comprises a ventilator airflow analyzer, an automated switch module for simulated lungs, and a test control platform. Under the control of testing software, this system can perform automated tests of critical performance parameters of ventilators and generate a final test report. To validate the effectiveness of the designed system, tests were conducted on two different brands of ventilators under four different operating conditions, comparing tidal volume, oxygen concentration, and positive end expiratory pressure accuracy using both the automated testing system and traditional manual methods. Bland-Altman statistical analysis indicated good consistency between the accuracy of automated tests and manual tests for all respiratory parameters. In terms of testing efficiency, the automated testing system required approximately one-third of the time needed for manual testing. These results demonstrate that the designed automated testing system provides a novel approach and means for quality inspection and measurement calibration of ventilators, showing broad application prospects.
Ventilators, Mechanical/standards* ; Equipment Design ; Humans ; Automation

As a relatively novel technique for drug delivery, the needle-free injection technique is characterized by transporting the drug liquid to the designated subcutaneous position through a high-speed micro-jet. Although this technique has been applied in many fields, the research on its drug dispersion mechanism and injection performance is insufficient. The presented study aims to identify critical parameters during the injection process and describe their influence on the injection effect. The injection completion rate and performance of a needle-free injector under various operating conditions were compared based on mouse experiments. The results show that the nozzle diameter imposes a more significant influence on jet characteristics than other injection parameters. Moreover, the injection completion rate increases with the nozzle diameter. The nozzle diameters of 0.14 mm and 0.25 mm correspond to injection completion rates of 89.7% and 95.8%, respectively. Furthermore, by analyzing the rate of blood glucose change in the tested mice, it is found that insulin administration through the needle-free injection can achieve a drug effect duration longer than 120 min, which is better than that obtained using conventional needle-syringe technique. In summary, the obtained conclusions can provide an important reference for the optimal design and extending application of the air-powered needle-free injector.
Animals ; Mice ; Insulin/administration & dosage* ; Needles ; Injections, Subcutaneous/methods* ; Injections, Jet/instrumentation* ; Drug Delivery Systems/instrumentation* ; Blood Glucose/analysis* ; Equipment Design

Tesla blood pumps demonstrate a reduced propensity for hemolysis and thrombosis compared with vane blood pumps. Considering the restricted driving force within the secondary flow channel of vane blood pumps, along with the low hydraulic efficiency of conventional Tesla blood pumps and their internal flow characteristics that significantly contribute to hemolysis and thrombosis, this study introduces a set of vanes atop the rotor of the Tesla blood pump. This forms a dual-fluid domain rotor, and an axial dual-outlet volute shell structure is adopted to realize the separation of the fluid domains. Through numerical simulations of the new structure, a comparative analysis was conducted in this study on the internal flow characteristics of double-outlet and single-outlet volute shells, and symmetric and asymmetric cross-sections of the same rotor. The results indicate that the flow field distribution is more uniform under the double-outlet volute shell structure, and overall energy dissipation is decreased. After implementing the double-outlet design, in the asymmetric cross-section, compared with the symmetric cross-section, the fluid velocity gradient and turbulent kinetic energy at the tongue of the septum are reduced, and the fluid velocity gradient at the convergence of the diffuser tube outlets are also decreased. The maximum scalar stress is lower, and the decline in head and efficiency is mitigated. Moreover, compared with the single-outlet volute shell, the hemolysis index in the asymmetric cross-section is reduced. In summary, this paper proposes a novel dual-outlet centrifugal disk blood pumps, which can provide a reference for the structural design and performance optimization of magnetically levitated centrifugal blood pumps.
Heart-Assist Devices ; Humans ; Equipment Design ; Hemolysis ; Computer Simulation

Drug administration via hollow microneedles (HMN) have the advantages of painlessness, avoidance of first-pass effect, capability of sustained infusion, and no need for professional personnel operation. In addition, HMN can also be applied in the fields of body fluid extraction and biosensors, showing broad application prospects. However, traditional manufacturing technologies cannot meet the demand for low-cost mass production of HMN, limiting its widespread application. This paper reviews the main manufacturing technologies used for HMN in recent years, which include photolithography and etching, laser etching, sputtering and electroplating, micro-molding, three-dimensional (3D) printing and drawing lithography. It further analyzes the characteristics and limitations of existing manufacturing technologies and points out that the combination of various manufacturing technologies can improve production efficiency to a certain extent. In addition, this paper looks forward to the future trends of HMN manufacturing technology and proposes possible directions for its development. In conclusion, it is expected that this review can provide new ideas and references for follow-up research.
Printing, Three-Dimensional ; Needles ; Humans ; Drug Delivery Systems/methods* ; Equipment Design ; Microinjections/methods*

To address the challenges of capturing micro-strains in detecting esophageal motility disorders and the limitations of existing high-resolution manometry and functional intraluminal imaging probes in directly measuring esophageal tissue electrical impedance, this study proposes a novel flexible balloon sensor structure that integrates a piezoelectric film assembly with a distributed impedance electrode array. Using the electrical analysis module in the finite element analysis (FEA) software, simulations of the forward problem for esophageal impedance detection were conducted to optimize the excitation source parameters, and a physical prototype was fabricated. Under a relative excitation mode with a voltage sensitivity of 2.059%, the voltage output characteristics of the impedance electrode array were analyzed during linear changes in the balloon filling volume. Based on the performance variation of the piezoelectric film assembly, 80% was selected as the optimal filling volume. Force-electric coupling tests were conducted on the balloon sensor using a pressure testing platform, revealing that both the piezoelectric film assembly inside the balloon and the impedance electrodes outside the balloon exhibited significant load differentiation characteristics as the force application point shifted. In summary, this balloon sensor facilitates the localization of force application while simultaneously analyzing esophageal tissue properties, offering a novel diagnostic approach and objective tool for esophageal disease detection.
Esophagus/physiology* ; Electric Impedance ; Humans ; Finite Element Analysis ; Manometry/methods* ; Electrodes ; Esophageal Motility Disorders/physiopathology* ; Equipment Design

The therapeutic effects of transcranial magnetic stimulation (TMS) are closely related to the structure of the stimulation coil. Based on this, this study designed an A-word coil and proposed a multi-strategy fusion multi-objective slime mould algorithm (MSSMA) aimed at optimizing the stimulation depth, focality, and intensity of the coil. MSSMA significantly improved the convergence and distribution of the algorithm by integrating a dual-elite guiding mechanism, a hyperbolic tangent control strategy, and a hybrid polynomial mutation strategy. Furthermore, compared with other stimulation coils, the novel coil optimized by the MSSMA demonstrates superior performance in terms of stimulation depth. To verify the optimization effects, a magnetic field measurement system was established, and a comparison of the measurement data with simulation data confirmed that the proposed algorithm could effectively optimize coil performance. In summary, this study provides a new approach for deep TMS, and the proposed algorithm holds significant reference value for multi-objective engineering optimization problems.
Algorithms ; Transcranial Magnetic Stimulation/instrumentation* ; Equipment Design ; Humans

In order to solve the problems of difficult test, high cost and long cycle in the development of large-scale airborne negative pressure isolation system, the simulation analysis of negative pressure response characteristics is carried out around various aviation conditions such as aircraft ascending, leveling and descending, especially rapid decompression, based on the computational fluid dynamics (CFD) method. The results showed that the isolation cabin could achieve -50 Pa pressure difference environment and form a certain pressure gradient. The exhaust air volume reached the maximum value in the early stage of the aircraft's ascent, and gradually decreased with the increase of altitude until it was level flying. In the process of aircraft descent, the exhaust fan could theoretically maintain a pressure difference far below -50 Pa without working; Under the special condition of rapid pressure loss, it was difficult to deal with the rapid change of low pressure only by the exhaust fan, so it was necessary to design safety valve and other anti-leakage measures in the isolation cabin structure. Therefore, the initial stage of aircraft ascent is the key stage for the adjustment and control of the negative pressure isolation system. By controlling the exhaust air volume and adjusting parameters, it can adapt to the change of low pressure under normal flight conditions, form a relatively stable negative pressure environment, and meet the needs of biological control, isolation and transport.
Aircraft ; Computer Simulation ; Aviation/instrumentation* ; Humans ; Hydrodynamics ; Air Pressure ; Equipment Design ; Pressure

In recent years, prone mechanical ventilation has been widely used to improve oxygenation dysfunction in critically ill patients. During prone mechanical ventilation, the patient's face is compressed for a long time, and due to the difficulty in changing, facial pressure injuries and ocular complications are common and severe. These complications increase patient discomfort, reduce their tolerance and compliance with prone ventilation, and even cause tracheal tube displacement or dislodgement, leading to significant clinical challenges. In order to change this situation, the medical staff of the department of critical care medicine of the Second People's Hospital of Hengshui and the department of critical care medicine of Harrison International Peace Hospital had developed an adjustable facial support pad for prone ventilation, and obtained a National Utility Model Patent of China (ZL 2022 2 3295294.4). The device is composed of a facial support platform, a supporting telescopic foot frame and so on. There are front, back, left and right adjustable tracks below the support cushion platform, which can be adjusted to the best state suitable for the patient's face shape, which can alleviate the facial pressure injuries and ocular complications caused by the different sizes of each patient's face, improve the patient's comfort, and reduce the incidence of facial pressure injury and the occurrence of ocular complications of the patient. The height of the platform is adjusted by the telescopic feet, and there is a hook assembly below, which can be fixed by the clamp of the ventilator tubing, so as to prevent the ventilator tubing from pulling the endotracheal intubation due to the gravity of condensation, resulting in the displacement or even prolapse of the tracheal intubation, and reducing the occurrence of adverse events of tracheal intubation. It is worth promoting in the clinic.
Humans ; Respiration, Artificial/methods* ; Prone Position ; Equipment Design ; Face

Peritoneal dialysis (PD) is one of the main renal replacement therapy methods for patients with end-stage chronic kidney disease, and peritoneal dialysis belt is a key auxiliary device. However, there are some problems in the existing PD technology, such as the separation of heating system and dialysate system, the inability to continuously heat dialysate and the single function of peritoneal dialysis belt. In order to solve the above problems, the staff of Shanghai Geriatric Medical Center designed an intelligent temperature-controlled peritoneal dialysis belt and obtained the National Utility Model Patent of China (patent number: ZL 2023 2 1815961.9). The intelligent temperature-controlled peritoneal dialysis belt is composed of a double-layer fixed belt, an intelligent temperature control system (including temperature control structure and intelligent control system) and other auxiliary structures. The peritoneal dialysis tube can penetrate into the dissection from the entry of the inner surface of the fixed belt and pass through the exit of the outer surface. The double-layer fixed belt ensures the stable fixation of the dialysis tube. The two ends of the fixing belt are designed with magic stickers to adjust the tightness of the fixing belt to adapt to people with different waist circumferences. The interlayer is equipped with an intelligent temperature control system, which can continuously heat the dialysate through an electric heating plate to maintain a temperature close to the body temperature. Through the display screen and controller on the intelligent control system, medical staff can be allowed to monitor and adjust the temperature, pressure and flow parameters of the dialysate in real time. In addition, a cloth with a pulling chain is designed on the inner surface of the fixed belt, and the cloth is opened to facilitate the medical staff to wear the peritoneal dialysis tube in the temperature control structure or the restraint belt. The intelligent temperature-controlled peritoneal dialysis belt enhances the effectiveness of PD, saves PD resources, improves the convenience of PD, is suitable for family and hospital use, can effectively improve the quality of life of patients with chronic renal failure, and is suitable for clinical promotion.
Peritoneal Dialysis/instrumentation* ; Humans ; Equipment Design ; Temperature ; Kidney Failure, Chronic/therapy* ; Dialysis Solutions

During cardiopulmonary resuscitation (CPR), the depth of compression is a critical factor affecting the effectiveness of the rescue and the patient's prognosis. However, it is difficult to master the correct compression depth in manual CPR. If the compression depth is too deep, it may cause rib fractures, while insufficient compression depth may fail to establish effective circulation. Although most existing manual CPR compression depth control devices can indicate the depth but lack direct limiting functions. Against this background, led by a team of faculty and students from the Department of Emergency and Rescue Medicine at Xuzhou Medical University, on the basis of the development of a portable CPR protection device (National Invention Patent of China, patent number: ZL 2021 1 0309001.4), the device's compression depth limiting performance was further expanded, and then a new type of CPR compression depth limiting device suitable for different body types was developed. This device has applied for a National Invention Patent of China (patent application number: ZL 2023 1 0644910.2) and has been granted a National Utility Model Patent of China (patent number: ZL 2023 2 1384853.0). The device consists of a horizontal support beam, a vertical sliding beam, a guide block, a rotating shaft, a rotating arm, a limit slider and a limit pin. The horizontal support beams of the two limit devices are fixed horizontally to the horizontal side beams of the portable CPR protection device by bolts, and the connecting arms at the bottom of the vertical sliding beams are fixedly connected with the pressing mechanism, so that precise control of the pressing depth in CPR operation can be realized according to the patient's body size by the mechanical linkage of the vertical sliding beams and the rotating arms, as well as by the blocking and limiting effect of the rotating arms and the guiding blocks on the limiting sliders. It can prevent the occurrence of complications such as chest wall fractures, and thereby increase the success rate of manual CPR, and its structure is simple, low-cost, and suitable for social popularization.
Cardiopulmonary Resuscitation/instrumentation* ; Humans ; Equipment Design ; Pressure