A backpack design is the best solution for a conceptual design of a Wearable Artificial Kidney.

Background: For hemodialysis patients, a miniaturized wearable artificial kidney (WAK) would allow for more freedom of movement and maintenance of a higher quality of life. In order to be truly wearable (and not only portable), not only single components, but even the device as a whole has to be designed in a convenient layout. The aim of this abstract is to propose a new concept of layout for wearable artificial kidney and to compare it with previous proposals. Methods: The WAK general layout has to be designed providing ergonomics and low weight, respecting the consequential phases of blood ultrafiltration process. Furthermore, the patient should not be hindered while performing daily activities and should not feel embarrassed wearing the device. Assuming a vascular access placed in jugular vein, four main proposals of layout have been considered, also based on previous proposals from literature: Belt-like device (horizontal arrangement); Jacket device (frontal arrangement); Sling shape device (frontal and vertical arrangement); Backpack device (rear and vertical arrangement). Results: The last option seems to meet the requirements better than the others. A backpack design (commonly used in everyday life) would offer more space for the components and cause less discomfort for the patient. A schematic preliminary draw of the device is represented in Fig.1 . Conclusions: With a backpack design, hemodialysis patients would use their own personal device only, in which all the disposable components could be replaced as a unique cartridge, designed to be extremely easy to fit and dispose. Furthermore, the backpack shape can be re‑arranged into a “sleep station” to perform night treatments as well.