Obstetric Shock Index
Enter the heart rate and systolic BP to see the shock index.
Notes
Blood loss is always underestimated, and in pregnancy hypotension is a late sign: hypovolaemia may not show until 35–40% of the circulating volume is lost. The shock index rises earlier than either the heart rate or the BP alone, which is why it is used as an adjunct.
Read it with the rest of the picture — tachycardia, reduced pulse pressure, delayed capillary refill, oliguria — not on its own.
Managing the cause: see the PPH note and the maternal collapse and shock note.
Show formula
Shock index = heart rate ÷ systolic BP
Normal in pregnancy: 0.7–0.9
> 1: may indicate occult shock
> 1.7: urgent intervention required
Sources
- Obstetrical and Gynaecological Society of Malaysia (OGSM). Handbook of Obstetric Emergencies (ICOE).
- Obstetric Life Saving Skills (OLSS) lectures, Hospital Sultan Haji Ahmad Shah (HOSHAS), Temerloh, 2026.