How the ICU follows orders: care delivery as a complex activity system.

In this paper, we use the theory of distributed cognition to understand work practices in terms of the behavior of an activity system. We do so by detailing the roles that local representations of information play in the social, cognitive, organizational, and technological processes that accomplish task work. Specifically, we characterize a portion of the medication order process in an Intensive Care Unit. In this setting, the processes that execute a medication order have evolved to accomplish the primary tasks of medication administration and also to simultaneously support other important aspects of the unit's work. Designers of systems that centralize and automate information resources must consider the diverse and latent roles played by information in order to improve design and to anticipate how their products affect complex care delivery systems.