Shock Index

Shock Index

Shock index is a simple bedside measure introduced by Allgower and associates [1] as early as 1967. The index is the ratio of heart rate to systolic blood pressure. Normal range of the index is between 0.5 and 0.7 in healthy adults. Index of 1.0 or more indicates a poor prognosis in acute circulatory failure.

Pulse pressure along with the index has been suggested as a trigger for initiation of prehospital blood transfusion by emergency services in case of hemorrhagic shock [2]. The investigators noted that positive predictive value for death for patients with pulse pressure of less than 45 and the index greater than 1 was 0.78. In blunt trauma patients it was 0.79 and much higher in elderly patients, 0.92. The index has been shown to predict mortality in geriatric influenza patients presenting to the emergency department [3].

References

1. Allgower M, Buri C. Shock index. Deutsche Medizinische Wodenschrift. 1967;46:1–10.
2. Caroline S Zhu, Danielle Cobb, Rachelle B Jonas, Douglas Pokorny, Meenakshi Rani, Tracy Cotner-Pouncy, Jenny Oliver, Andrew Cap, Ramon Cestero, Susannah E Nicholson, Brian J Eastridge, Donald H Jenkins. J Trauma Acute Care Surg. 2019 Jul;87(1S Suppl 1):S159-S164.
3. Jui-Yuan Chung, Chien-Chin Hsu, Jiann-Hwa Chen, Wei-Lung Chen, Hung-Jung Lin, How-Ran Guo, Chien-Cheng Huang. Am J Emerg Med. 2019 Mar;37(3):391-394.