The perioperative period poses significant risks of complications, particularly cardiovascular, which are the leading causes of morbidity and mortality in non-cardiac surgeries. This paper presents the development of a rule-based expert system for perioperative monitoring and cardiovascular complication detection, intended to support anesthesiologists and medical technicians. Using knowledge derived from a domain expert and relevant literature, the system leverages the Drools rule engine to assist in preoperative, intraoperative, and postoperative care. The system collects patient data, evaluates patients’ health status and monitors vital signs in real time during and after surgery. Abnormalities such as hypertension, tachypnea, and hypoxemia trigger alerts, enabling quick interventions. In the postoperative phase, the system aids in detecting complications by analyzing vital signs and entered symptoms. The proposed solution reduces cognitive load on medical staff, enhancing patient safety and outcomes through real-time monitoring and personalized decision-making. Future enhancements will involve integrations with hospital information systems and the expansion of the knowledge base to include anesthetic dosage calculations.