II. Indications
III. Background
- Shock Index provides early identification of compensated shock at risk for decompensation
- Shock Index may indicate more ill patients with less reserve when Blood Pressure is "soft" without frank Hypotension
- Diastolic Shock Index similarly may identify compensated shock patients
- Catecholamine surge may transiently raise Blood Pressure by increasing Heart Rate, Cardiac Output and vascular tone
- Catecholamine surge may be signaled by episodic Hypotension that corrects
- However, ultimately Hypotension is expected when Catecholamine effects are exhausted
- Catecholamine surge may transiently raise Blood Pressure by increasing Heart Rate, Cardiac Output and vascular tone
IV. Exam: Shock Index (Systolic Shock Index)
- Shock Index = (Heart Rate) / (Systolic Blood Pressure)
- Systolic Blood Pressure reflects Cardiac Output
- Interpretation
- Efficacy
- Shock Index (by contrast with Vital Signs) does correlate with degree of Hemorrhage
- Mutschler (2013) Crit Care 17(4): R172 [PubMed]
V. Exam: Diastolic Shock Index (DSI)
- Diastolic Shock Index = (Heart Rate) / (Diastolic Blood Pressure)
- Diastolic Blood Pressure reflects vascular tone (Peripheral Vascular Resistance)
- Interpretation
- Compensated Shock at risk of decompensation: >2.5
VI. References
- Weingart and Swaminathan in Swadron (2022) EM:Rap 22(11): 2-3