Undifferentiated Shock

  • Russell G. DayEmail author
  • Sage P. Whitmore


Undifferentiated shock is commonly encountered in the critical care environment. Medically complex patients may have clinical features of and risk factors for multiple types of shock, and uncovering the etiology can be challenging. The three major types of shock are hypovolemic, distributive, and cardiogenic (including obstructive). Frequently, patients have more than one shock type occurring simultaneously. The most reliable means of guiding initial management of undifferentiated shock are to accurately determine volume responsiveness and to rapidly carry out focused point-of-care ultrasound, particularly bedside echocardiography. These steps will focus the clinician on the most likely type(s) of shock, influence the proper use of fluids, vasopressors and inotropes, and provide a starting point for an expedited work-up and early therapeutic interventions.


Hypotension Shock Shock types Cardiogenic Distributive Septic Hypovolemic Volume responsiveness Fluid resuscitation Bedside echocardiography Ultrasound Point-of-care ultrasound Central venous pressure Cardiac output monitoring 


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Copyright information

© This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply 2020

Authors and Affiliations

  1. 1.Division of Emergency Critical Care, Emergency MedicineUniversity of Michigan Health SystemAnn ArborUSA
  2. 2.Tristar Centennial Medical CenterNashvilleUSA

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