We present a web-based vital signs simulator (HTML5 / CSS / JavaScript) for clinical teaching and initial triage training. The system integrates: i) generation of pathophysiological scenarios (septic, hypovolemic, cardiogenic, anaphylactic shock, and healthy patient); ii) real-time monitoring of variables (HR, RR, systolic/diastolic BP, temperature, and SpO2); iii) synthetic ECG with HTML5; iv) prognosis tutor with pedagogical rules; and v) a follow-up module with a severity ranking inspired by TOPSIS. The simulator achieves a Haemodynamic Stability Index (HSI) of up to 0.60 for optimal interventions (e.g., IV fluids in hypovolemic shock) and a Therapeutic Effectiveness Coefficient (TEC) of 1.0 for correct actions, as validated with synthetic data. We describe the architecture, physiological heuristics, and user flow. Validation is currently limited to synthetic data, with future work planned for user testing and external clinical validation. We describe the architecture, data design, physiological heuristics, and user flow, and propose extensions to turn it into a reproducible evaluation environment (metrics, testing, PWA packaging, and educational analytics). The system not only facilitates diagnostic and prognostic practice but also serves as a platform for analysis and critical decision-making in the care of patients in shock, demonstrating its potential as a teaching and support tool in clinical practice.