Patient medical records contain a great number of information distributed in different kinds of documents: diagnosis, prescription, symptoms observations or radiology analysis, etc. Documents heterogeneity makes specific information retrieval difficult to the medical staff members. This paper shows how a semantic model of documents enables handling information stored in these documents. It enables the definition of a generic semantic structure of a medical record: this structure expresses the implicit content of the each document's element by specifyingwhat kind of information is required. Moreover, it enables to display relevant information depending on the reader.