UMEM Educational Pearls

Category: Critical Care

Title: Shock Index

Posted: 12/8/2009 by Mike Winters, MD (Updated: 4/20/2024)
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Early Recognition of Shock

Early recognition, and thus early treatment, of shock is crucial in reducing morbidity and mortality in the critically ill ED patient.
Traditionally, the diagnosis of shock has been based on vital sign abnormalities such as tachycardia, tachypnea, oliguria, etc.
Vital sign abnormalities have been shown to be insensitive markers of shock in the critically ill.
The Shock Index, although clearly not 100% sensitive, can assist in the detection of shock compared to heart rate and blood pressure alone.
Shock Index is simply heart rate divided by systolic blood pressure.
Values greater than 0.9 are abnormal and suggest markedly impaired cardiac output.

Strehlow MC. Early identification of shock in critically ill patients. Emerg Med Clin N Am 2010:28:57-66.