In this paper we discuss how dynamic updates in a sparse mobile ad-hoc network can be handled in a rescue scenario. As rescue operations have an organisational and operational structure, updates can take advantage of rescue operation roles and lines of reporting, together with update priorities. To illustrate this, we give a short description of our rescue scenario, together with an outline of our multi-tier data dictionary solution that makes use of semantic linked distributed data dictionaries and ontology enhanced metadata descriptions. We present an example ontology of profiles for user, device, rescue scenario, and information items, tailored for ontology based dynamic updates.