PALS Provider: Course

Algorithm for Hypovolemic Shock

Hypovolemic shock occurs due to a critical loss of intravascular volume, leading to inadequate tissue perfusion and oxygen delivery. It is the most common type of shock in children, often resulting from dehydration, hemorrhage, or burns.

Key Goals of Treatment

  • Rapidly restore intravascular volume to maintain perfusion.
  • Optimize oxygen delivery to prevent organ failure.
  • Address the underlying cause (e.g., dehydration, hemorrhage).

Recognition: Signs of Hypovolemic Shock

Early (Compensated) Signs:

  • Tachycardia (earliest and most sensitive sign)
  • Weak peripheral pulses but strong central pulses
  • Cool, clammy, or mottled skin
  • Delayed capillary refill (>3 seconds)
  • Decreased urine output (<1 mL/kg/hr)
  • Irritability, restlessness (early mental status changes)

Late (Decompensated) Signs:

  • Hypotension (late and ominous sign)
  • Severe lethargy or unresponsiveness
  • Absent or thready pulses
  • No urine output (anuria)

Note: Hypotension is a late and life-threatening sign in children—treat shock aggressively before it occurs.

Management Algorithm for Hypovolemic Shock

  • Step 1: Provide High-Flow Oxygen
    Administer 100% oxygen via non-rebreather mask.
    If respiratory distress or mental status worsens, consider assisted ventilation.
  • Step 2: Establish Vascular Access (IV or IO)
    - First-line: Peripheral IV (20G or larger).
    - If IV not obtained within 60–90 sec: Place IO access.
    - Draw labs: electrolytes, glucose, lactate, Hgb, Hct.
  • Step 3: Rapid Fluid Resuscitation
    - Give 20 mL/kg boluses of isotonic fluids (NS or LR) over 5–10 min.
    - Reassess after each bolus: heart rate, cap refill, pulses, urine output, mental status.
    - Repeat up to 60 mL/kg if no improvement.
    - If no response: consider PRBC transfusion (if hemorrhage) or inotropes (fluid-refractory shock).
  • Step 4: Reassess Continuously
    - If perfusion improves: transition to maintenance IV fluids and monitor.
    - If still unstable:
    • Suspected hemorrhage → 10 mL/kg PRBCs
    • Still hypotensive → Start vasopressors (dopamine, norepinephrine)
    • Monitor for fluid overload (pulmonary edema, hepatomegaly)
  • Step 5: Treat the Underlying Cause
    - Dehydration → continue fluids, correct electrolytes.
    - Hemorrhage → stop bleeding, transfuse blood.
    - Burns → calculate and replace fluids (e.g., Parkland formula).
    - Sepsis → antibiotics + fluids ± vasopressors.

Quick Reference: Pediatric Hypovolemic Shock Management

Step Action Key Considerations
1 Oxygen 100% via non-rebreather, assist ventilation if needed
2 IV/IO Access IV first, IO if IV fails within 60–90 sec
3 Fluids: 20 mL/kg NS/LR Repeat up to 60 mL/kg, reassess after each bolus
4 Monitor Response Perfusion, urine output, mental status
5 Identify Cause Dehydration, hemorrhage, burns, sepsis

When to Escalate Beyond Fluids?

Condition Next Steps
Hemorrhage Transfuse 10 mL/kg PRBCs, control bleeding
Sepsis Start vasopressors (epinephrine, norepinephrine)
Cardiogenic shock (suspected) Avoid aggressive fluids, start inotropes
DKA Avoid rapid fluids—risk of cerebral edema

Signs of Improvement After Fluid Resuscitation

  • Heart rate normalizes
  • Peripheral pulses strengthen
  • Capillary refill <2 seconds
  • Urine output >1 mL/kg/hr
  • Mental status improves

If these signs are absent, continue resuscitation and assess for fluid-refractory shock.

Summary: Why Rapid Recognition and Treatment Matters

  • Tachycardia is the earliest sign—intervene before hypotension.
  • Give 20 mL/kg boluses of isotonic fluids, reassessing frequently.
  • If no response after 60 mL/kg, consider PRBCs or vasopressors.
  • Always identify and address the underlying cause.

Takeaway: Pediatric hypovolemic shock requires rapid intervention—early fluid resuscitation and cause-specific management can save lives.