The Shock Index makes it possible to assess the seriousness of a patient in a state of shock, in particular in polytraumatized patients. An index ≥ 0.9 is correlated with high mortality. On a haemorrhage, a high index or modified index can help establish the indication for transfusion.
Index = Heart Rate ÷ Systolic Blood Pressure.
Modified Index = Heart Rate ÷ Mean Blood Pressure.