Objective To develop a miniature negative pressure aspirator with easy operation,stable negative pressure,low weight,small volume and high portability.Methods A double-faced printed circuit board with a size of 6 cm×4 cm×1 cm was manufactured with the functions of regulating the current and DC/AC conversion.DC vacuum pump and Panasonic li-ion battery pack were used to generate the desired pressure between-0.017 and-0.060 MPa,and mechanically-driven deformation vacuum gauge was involved in manufacturing the aspirator.Two sizes (150 and 200 ml) of drainage bottles were made of medical silica gel.Results The aspirator facilitated negative-pressure therapy when the patient was walking or discharged,which decreased the hospital cost and stay.Conclusion The aspirator gains advantages in stable negative pressure,low power consumption,easy operation and high safety,and thus is worthy promoting clinically.

Objective To design and manufacture a multifunctional cushion for venous thrombosis prevention of lower extremities, which can be also applied to the low extremities needing raising. Methods The cushion was made of anti-rust, low-weight, undeformable and easy-to-clean stainless material, which was composed of a pad and a massage apparatus. The pad had its height regulable from 16 to 30 cm and telescopic inclination from 30 to 70° to adapt the cushion to sizes of patients. There were 6 independent air chambers and tubular circulating pipes around the blanket wrapping the chambers so that extremity massage and temperature-controlled heating could be executed based on setting up pressure, time and temperature of the electromagnetic air and water pumps. Results The cushion simulated the functions of the muscle pump, which formed step-by-step-increasing pressure changes by driving the chambers to be inflated and discharged continuously to execute extremity massage, temperature-controlled heating etc. Conclusion The cushion gains advantages in flexible composition, patient comfort etc, solves the problems in fixing angle and height, constant time for pump inflation and discharge as well as temperature-controlled heating, and thus is worthy promoting clinically.