The present paper presents an intelligent system which determines the need for readmission in postoperative patients of ambulatory surgery, after being discharged. The decision made by the system depends on the answers given to a follow-up questionnaire, which includes questions related to the recovery state of the patient, and information about his/her medical records stored in a database. In order to carry out the system, Artificial Neural Networks (ANNs) were implemented to model clinical decision-making, by using different configurations of ANN, to select the one that presented the highest success rate in the decision.