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)
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) Quickly
- First-line: Peripheral IV access (large bore, 20G or larger if possible).
- If IV fails within 60-90 seconds: Place Intraosseous (IO) access immediately.
- Draw blood for labs: Electrolytes, glucose, lactate, hemoglobin, hematocrit.
Step 3: Rapid Fluid Resuscitation
Administer isotonic fluids (NS or LR) in 20 mL/kg boluses over 5-10 minutes. Reassess after each bolus for signs of improved perfusion:
- Normal heart rate
- Improved pulses and capillary refill
- Increased urine output
- Improved mental status
If signs of shock persist: Repeat 20 mL/kg boluses up to 60 mL/kg total. If still no improvement: Consider blood transfusion (if hemorrhagic shock) or inotropes (if fluid-refractory).
Avoid hypotonic fluids (D5W, 0.45% NaCl) in shock, as they can worsen hypotension and cerebral edema.
Step 4: Reassess and Continue Fluid Resuscitation as Needed
- If perfusion improves: Transition to maintenance IV fluids and monitor closely.
- If no improvement after 60 mL/kg of fluids: Hemorrhage suspected? → Give blood transfusion (10 mL/kg packed RBCs). Still unstable? → Start vasopressors (dopamine, norepinephrine) for ongoing shock. Monitor for signs of fluid overload (pulmonary edema, hepatomegaly).
Step 5: Identify & Treat the Underlying Cause
Dehydration (e.g., gastroenteritis, DKA) → Continue IV fluids and electrolyte correction. Hemorrhage (e.g., trauma, GI bleeding) → Control bleeding, transfuse PRBCs. Burns → Provide aggressive fluid replacement using the Parkland formula. Sepsis → Continue IV fluids, start broad-spectrum antibiotics, consider vasopressors.
Special Considerations for Hemorrhagic Shock: If severe blood loss, give 10 mL/kg packed RBCs instead of more crystalloid. Massive transfusion protocol if ongoing hemorrhage. Consider tranexamic acid (TXA) for major trauma.
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?
If shock persists despite 60 mL/kg of 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 (dobutamine, epinephrine)
DKA (Diabetic Ketoacidosis) Avoid rapid fluids—risk of cerebral edema
If worsening respiratory distress (pulmonary edema), STOP fluids and consider vasopressors instead.
SIGNS OF IMPROVEMENT AFTER FLUID RESUSCITATION
Heart rate normalizes (tachycardia resolves). Peripheral pulses strengthen. Capillary refill <2 seconds. Urine output >1 mL/kg/hr. Mental status improves (alert, responsive).
If these signs are absent, continue resuscitation and reassess for fluid-refractory shock.
SUMMARY: WHY RAPID RECOGNITION AND TREATMENT MATTERS
Tachycardia is the earliest sign—act before hypotension occurs! Give isotonic fluids (NS or LR) in 20 mL/kg boluses, reassessing after each one. If shock persists despite 60 mL/kg of fluids, consider blood transfusion or vasopressors. Identify and treat the underlying cause to ensure complete recovery.
Takeaway: Pediatric hypovolemic shock requires rapid intervention—early fluid resuscitation and cause-specific management can save lives.