What is Asgaard?

Project Description

The aim of the Asgaard/Asbru project is to design a set of tasks that support the design and the execution of skeletal plans by a human executing agent other than the original plan designer. Skeletal plans area powerful way to reuse existing domain-specific procedural knowledge, but leave room for execution-time flexibility to achieve particular goals.

The underlying requirement to develop task-specific problem-solving methods is a modeling language. Therefore, within the Asgaard project, we are developing a time-oriented and intention-based plan-representation language, called Asbru, to represent time-oriented skeletal plans.

During the design phase of plans, Asbru allows to express durative actions and plans caused by durative states of an observed agent. During the execution phase, Asbru allow flexibility to instantiate the skeletal plans with time-oriented patient data. The intentions underlying these plans are represented explicitly as temporal patterns to be maintained, achieved or avoided.

Figure 1 illustrates the aimed system organization and its interactions. The inputs are to the planner are time-oriented raw data (e.g., patient data) and raw protocols (e.g., clinical protocols). The data are acquired from electronic devices or entered by the users. The protocols will be represented and transformed in a sharable representation (the sharable skeletal plan library).

The reasoning, based on the sharable plan-library and on the interaction with the user's needs and tasks, results in context-sensitive support, like recommendations, explanations, or visualization of the available and necessary data.

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Figure 1: The Asgaard Idea

Design Time versus Execution Time

During design time of a clinical guideline, an author (or a committee) designs a guideline. The author prescribes (1) conditions, that need to hold at particular plan steps (e.g., subject is female, blood gas has been above the target range for at least five minutes) (2) actions (e.g., administer a certain drug in the morning and in the evening), (3) an intended plan-the intended intermediate and overall pattern of actions, which might not be obvious from the description of the prescribed actions and is often more flexible than prescription of specific actions (e.g., use some drug from a certain class of drugs twice a day), and (4) the intended intermediate and overall pattern ofpatient states (e.g., morning blood glucose should stay within a certain range).

During execution time, a physician/nurse applies the guideline by performing actions, which are recorded, observed, and abstracted over time into an abstracted plan. The state of the patient also is recorded, observed, and abstracted over time. Finally, the intentions of the medical staff might be recorded too - inferred from her actions or explicitly stated by the medical staff.