ICU Concepts

Unit 02

Bedside Reasoning

Heart failure · Shock · Sepsis · DIC — five steps each. See it, understand it, connect it, act on it, apply it.

02 · Shock & Tissue Perfusion — Step 01 of 05 · See it

Shock is failed perfusion, not just low pressure

Shock is inadequate effective tissue perfusion and oxygen delivery resulting in cellular and organ dysfunction.

  1. 01

    VOLUME?

    Is the tank empty? Hemorrhage, fluid loss, severe dehydration.

  2. 02

    PUMP?

    Is the heart failing to eject? MI, severe HF, arrhythmia, myocardial depression.

  3. 03

    TONE?

    Have the vessels lost their squeeze? Sepsis, anaphylaxis, neurogenic injury.

  4. 04

    OBSTRUCTION?

    Is something physically blocking flow? Tamponade, massive PE, tension pneumothorax.

Normal cardiac output does not exclude shock. In early distributive shock, output can be normal or high while perfusion fails.

Tip: ← → keys move between steps.