What is the definition of shock?

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Last updated: April 20, 2025View editorial policy

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From the Guidelines

Shock is a life-threatening condition characterized by inadequate blood flow to body tissues, resulting in cellular dysfunction and potential organ failure, and is defined as a clinical state of hypoperfusion with signs of end-organ dysfunction, such as hypotension, oliguria, and altered mental status 1.

Classification of Shock

Shock can be classified into several types, including:

  • Hypovolemic shock, resulting from blood or fluid loss
  • Cardiogenic shock, resulting from heart dysfunction
  • Distributive shock, including septic, anaphylactic, and neurogenic shock
  • Obstructive shock, resulting from blockage of blood flow

Pathophysiology of Shock

The pathophysiology of shock involves initial compensatory mechanisms, such as increased heart rate and vasoconstriction, followed by decompensation when these mechanisms fail, leading to cellular damage from inadequate oxygen delivery and accumulation of metabolic waste products 1.

Clinical Presentation of Shock

Common signs of shock include:

  • Low blood pressure
  • Rapid heart rate
  • Cool and clammy skin
  • Confusion
  • Decreased urine output

Treatment of Shock

Treatment of shock depends on the underlying cause, but generally focuses on restoring adequate circulation through:

  • Fluid resuscitation
  • Vasopressors, such as norepinephrine (starting at 0.05-0.1 mcg/kg/min) or dopamine (5-20 mcg/kg/min)
  • Addressing the underlying cause
  • Supporting failing organs Immediate recognition and treatment are crucial, as shock can rapidly progress to irreversible organ damage and death 1.

From the Research

Definition of Shock

  • Shock is a life-threatening condition of circulatory failure leading to inadequate organ perfusion and tissue oxygenation 2
  • It is a pathological state that results when the circulation is unable to deliver sufficient oxygen and nutrients to the cells and tissues 3
  • Shock is a complex, life-threatening clinical condition that arises from acute circulatory failure 3
  • It causes an imbalance between cellular oxygen supply and demand resulting in organ dysfunction 4

Categories of Shock

  • Categories of shock include distributive, hypovolemic, obstructive, and cardiogenic 5
  • Distributive (and usually septic distributive) shock is the most common type 5
  • Other types of shock include hypovolemic, cardiogenic, and obstructive shock 6, 2

Pathophysiology of Shock

  • Shock results in hypoperfusion to vital organs, which can lead to organ failure and death if not quickly and appropriately managed 6
  • The resulting hypoxia, tissue hypoperfusion and cellular dysfunction can lead to multi-organ failure 3
  • Shock can transition to an irreversible phase if left untreated, resulting in multiorgan failure and subsequent death 4

Clinical Assessment and Management

  • Clinical history, physical examination, and hemodynamic assessments & monitoring help differentiate the different types of shock 5
  • An accurate diagnosis is necessary to initiate appropriate lifesaving interventions and target therapeutic goals specific to the type of shock 6
  • Rapid therapeutic intervention has been proven to decrease morbidity and mortality and is crucial to providing the best patient outcomes 6

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Shock in Trauma.

Emergency medicine clinics of North America, 2023

Research

Shock: aetiology, pathophysiology and management.

British journal of nursing (Mark Allen Publishing), 2022

Research

Shock.

Critical care nursing quarterly, 2022

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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