The practice of “ Fluid balance ” – Humans and artifacts in medical work

This paper is an attempt to take artifacts seriously. In the light of some basic questions – How do humans and nonhumans “connect”? How do they “interact”? How do they “work together?” – we are detailing two cases of medical work activity. Both cases deal with the practices of keeping patients “fluid balance”. One of the cases is from an ongoing dialysis project at our department. The other case is a revisit of a case described in literature. Our main conclusion is that the symmetry principle of Actor-Network theory does not hold true in our cases; on an operational level humans and nonhumans may be able to replace each other, but in work practices they do not. The second conclusion is methodological, namely that the level of description of the cases are decisive for what you may find out.