The idea of the vasculoid originated in the asking of a simple question: Once a mature molecular nanotechnology becomes available, could we replace blood with a single, complex robot? This robot would duplicate all essential thermal and biochemical transport functions of the blood, including circulation of respiratory gases, glucose, hormones, cytokines, waste products, and all necessary cellular components. The device would conform to the shape of existing blood vessels. Ideally, it would replace natural blood so thoroughly that the rest of the body would remain, at least physiochemically, essentially unaffected, but sustained in a cardioplegic state. It is, in effect, a mechanically engineered redesign of the human circulatory system that attempts to integrate itself as an intimate personal appliance with minimal adaptation on the part of the host human body.
A robotic device that replaces and extends the human vascular system is properly called a “vasculoid,” a vascular-like machine. But the vasculoid is more than just an artificial vascular system. Rather, it is a member of a class of space- or volume-filling nanomedical augmentation devices whose function applies to the human vascular tree.