Trauma Shock Index Calculator

About this calculator

The shock index is a simple bedside ratio — heart rate divided by systolic blood pressure — used in emergency and trauma medicine to flag possible hemodynamic instability before it becomes obvious from vital signs alone. A normal shock index sits around 0.5 to 0.7; values rising above roughly 0.9–1.0 can indicate significant blood loss or occult shock even when blood pressure still looks acceptable on its own, because heart rate often rises before blood pressure visibly drops.

This calculator computes the shock index from heart rate and systolic blood pressure. It's used by emergency physicians, trauma teams, and paramedics as a quick triage screening tool alongside other vital signs and clinical judgment — it's a research-backed early-warning indicator, not a diagnosis, and real patient assessment and treatment decisions are always made by trained clinicians examining the full clinical picture.