What is the 4:2:1 rule for fluid administration in medical settings, specifically referring to the 4 milliliters per kilogram (mL/kg) of crystalloid fluid, 2 mL/kg of colloid fluid, and 1 mL/kg of blood products?

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Last updated: May 2, 2025View editorial policy

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From the Guidelines

The 4:2:1 rule for fluid administration is not a recommended guideline for fluid resuscitation in sepsis and septic shock, as the Surviving Sepsis Campaign guidelines recommend an initial fluid challenge of at least 30 mL/kg of crystalloids 1.

Key Points

  • The Surviving Sepsis Campaign guidelines recommend crystalloids as the initial fluid of choice in the resuscitation of severe sepsis and septic shock 1.
  • The guidelines suggest using either balanced crystalloids or saline for fluid resuscitation of patients with sepsis or septic shock 1.
  • Albumin may be used in addition to crystalloids for initial resuscitation and subsequent intravascular volume replacement in patients with sepsis and septic shock, when patients require substantial amounts of crystalloids 1.
  • Fluid administration should be continued as long as hemodynamic factors continue to improve, using a fluid challenge technique 1.

Fluid Resuscitation

The goal of fluid resuscitation in sepsis and septic shock is to restore tissue perfusion and prevent organ dysfunction.

  • The initial fluid challenge should be at least 30 mL/kg of crystalloids, with more rapid administration and greater amounts of fluid may be needed in some patients 1.
  • Fluid therapy should be adjusted based on the patient's clinical status, including vital signs, urine output, and laboratory values.

Choice of Fluid

  • Crystalloids are the recommended fluid of choice for initial resuscitation and subsequent intravascular volume replacement in patients with sepsis and septic shock 1.
  • Balanced crystalloids or saline may be used for fluid resuscitation of patients with sepsis or septic shock 1.
  • Albumin may be used in addition to crystalloids for initial resuscitation and subsequent intravascular volume replacement in patients with sepsis and septic shock, when patients require substantial amounts of crystalloids 1.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

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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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