In order to solve the problems of insufficient stimulation channels and lack of stimulation effect feedback in the current electrical stimulation system, a functional array electrode electrical stimulation system with surface electromyography (sEMG) feedback was designed in this paper. Firstly, the effectiveness of the system was verified through in vitro and human experiments. Then it was confirmed that there were differences in the number of amperage needed to achieve the same stimulation stage among individuals, and the number of amperage required by men was generally less than that of women. Finally, it was verified that the current required for square wave stimulation was smaller than that for differential wave stimulation if the same stimulation stage was reached. This system combined the array electrode and sEMG feedback to improve the accuracy of electrical stimulation and performed the whole process recording of feedback sEMG signal in the process of electrical stimulation, and the electrical stimulation parameters could change with the change of the sEMG signal. The electrical stimulation system and sEMG feedback worked together to form a closed-loop electrical stimulation working system, so as to improve the efficiency of electrical stimulation rehabilitation treatment. In conclusion, the functional array electrode electrical stimulation system with sEMG feedback developed in this paper has the advantages of simple operation, small size and low power consumption, which lays a foundation for the introduction of electrical stimulation rehabilitation treatment equipment into the family, and also provides certain reference for the development of similar products in the future.
For the researches relating to the biomedical fields such as preparation of drug micro-particulates and biomedical materials coating, according to the modular design concept and combing the piezoelectric micro-jetting technology with electromechanical engineering and automatic control technology, the drug micro-jetting multifunctional system was designed, which included the spraying support subsystem, X-Y motion platform, Z-axis subsystem and rapid installation subsystem. The drug micro-jetting multifunctional system was run and adjusted. The versatility, rationality and feasibility of this system were validated by the experiments of amoxicillin microcapsule preparation, titanium alloy drug-loaded coating preparation and balloon electrode coating preparation. It was shown that the system can be used as basic platform in multi-disciplinary cross technology research such as biomedical engineering, pharmaceutical engineering and so on.
Objective To investigate the indications, procedures, risks and efficacy of extracorporeal membrane oxygenation (ECMO) in bronchoscopic interventional surgery for patients with severe airway stenosis. Methods Retrospective analysis was performed on 6 patients with severe airway stenosis treated by bronchoscopic surgery under ECMO in West China Hospital from January 2018 to July 2021, and the experience of application was summarized in combination with 23 relevant literatures retrieved. Results Six patients on ECMO successfully completed bronchoscopic interventional surgery with satisfactory intraoperative oxygenation and no obvious hemostasis difficulties were observed. ECMO placement was as an emergency medical countermeasure in 3 patients while the other 3 patients were as preventive purpose. Following treatment, the shortness of breath index and mMRC score decreased and the patients were cured and discharged. During hospitalization, 3 patients had lower extremity deep vein thrombosis, and 1 patient with lower extremity swelling and pain, which was relieved after treatment with low molecular weight heparin. During discharge follow-up, 1 patient died due to airway stenosis, pulmonary infection, and subarachnoid hemorrhage secondary to cardiopulmonary resuscitation, while the other 5 patients did not show any worsening of dyspnea. Combined with the retrieval of 46 similar cases reported in the literature before 2020, it was concluded that these patients who met the application indications of ECMO and followed the shutdown procedure had a good prognosis and controllable risk. Conclusions ECMO can ensure the safety of patients with severe airway stenosis who need undergoing bronchoscopic interventional surgery for patients, improve the success rate of the operation and do not significantly increase the risk of bleeding. However, ECMO is difficult to operate and requires professional team management. Therefore, it is essential to master the indications of application, implement strict withdrawal procedures and necessary monitoring to improve the patient's cure rate and reduce the occurrence of adverse events.