Shock Index Calculator
Haemodynamic assessment — Shock Index, MAP, and haemorrhagic shock classification.
Enter Vital Signs
Enter HR and SBP to calculate shock index.
Shock Index Interpretation
SI 0.5–0.7 — Normal
Haemodynamically stable. Monitor and reassess.
SI 0.7–0.9 — Mildly Elevated
Borderline. Monitor closely, establish IV access, consider fluid challenge.
SI 0.9–1.0 — Moderate Concern
Occult shock possible. Establish large-bore IV ×2, fluid resuscitation, urgent transport.
SI > 1.0 — Significant Shock
Aggressive resuscitation. Consider damage control. Immediate advanced intervention.
SI > 1.4 — Severe / Decompensated
Critical. Potential imminent cardiovascular collapse. Activate trauma team if available.
Haemorrhagic Shock Classes
| Class | Blood Loss | HR | BP | RR | GCS |
|---|---|---|---|---|---|
| I | <15% <750 mL |
<100 | Normal | 14–20 | 15 |
| II | 15–30% 750–1500 mL |
100–120 | Normal | 20–30 | 14–15 |
| III | 30–40% 1500–2000 mL |
120–140 | ↓ | 30–40 | 12–14 |
| IV | >40% >2000 mL |
>140 | ↓↓ | >35 | <12 |
Based on 70 kg adult. Blood volume ≈ 70 mL/kg (adult), ≈ 80 mL/kg (child).
MAP Formula
MAP = DBP + (SBP − DBP) ÷ 3
or MAP = (SBP + 2×DBP) ÷ 3
Normal MAP: 70–100 mmHg. MAP <65 mmHg = hypoperfusion. Target MAP ≥65 in septic shock (≥80 if pre-existing hypertension).
Clinical Disclaimer: Shock index and MAP are adjuncts only. Always integrate with full clinical assessment, mechanism of injury, and patient history. Follow your service protocols.