PALS Provider: Course
Algorithm for Distributive Shock
Distributive shock occurs due to abnormal vasodilation and maldistribution of blood flow, leading to inadequate tissue perfusion despite normal or increased cardiac output. The most common causes are sepsis, anaphylaxis, and neurogenic shock.
Key Goals of Treatment
- Restore adequate perfusion and prevent organ failure.
- Correct vasodilation with fluids and vasopressors.
- Identify and treat the underlying cause (e.g., infection, anaphylaxis, spinal cord injury).
Recognition: Signs of Distributive Shock
Early (Compensated) Signs:
- Tachycardia (earliest and most sensitive sign)
- Bounding pulses, widened pulse pressure (low diastolic BP)
- Warm extremities, flushed skin
- Altered mental status (irritability, confusion)
Late (Decompensated) Signs:
- Cold extremities
- Weak pulses, delayed capillary refill
- Hypotension (late sign)
- Lethargy, unresponsiveness
Key Differentiator: Warm extremities with bounding pulses = early distributive shock. Cold extremities with weak pulses = late, decompensated shock.
Management Algorithm for Distributive Shock
- Step 1: Administer High-Flow Oxygen
- 100% oxygen via non-rebreather mask.
- Consider intubation if respiratory distress worsens. - Step 2: Establish Vascular Access and Give IV Fluids
- IV or IO access immediately.
- 20 mL/kg isotonic crystalloid (NS or LR) over 5–10 minutes.
- Repeat up to 60 mL/kg as needed, reassessing after each bolus.
- Monitor for response: cap refill, urine output, mental status.
- Stop fluids and start vasopressors if signs of fluid overload. - Step 3: Initiate Vasopressors if Fluid Resuscitation Fails
| Condition | First-Line Vasopressor | Additional Therapy |
|---|---|---|
| Septic Shock | Norepinephrine, Dopamine | Epinephrine (cold shock) |
| Anaphylactic Shock | IM Epinephrine (first-line) | Antihistamines, corticosteroids |
| Neurogenic Shock | Norepinephrine, Dopamine | Atropine (if bradycardia) |
- Step 4: Identify and Treat the Underlying Cause
A. Septic Shock:
- Start broad-spectrum antibiotics within 1 hour.
- Neonates: Ampicillin + Gentamicin/Cefotaxime.
- Infants/Children: Vancomycin + Ceftriaxone/Cefotaxime.
- Consider hydrocortisone for refractory shock.
B. Anaphylactic Shock:
- IM Epinephrine 0.01 mg/kg (max 0.3 mg/dose), repeat every 5–15 min as needed.
- Add diphenhydramine + ranitidine, methylprednisolone, albuterol (if wheezing).
- IV Epinephrine infusion if IM dosing is ineffective.
C. Neurogenic Shock:
- Maintain spinal precautions.
- Use vasopressors for BP support.
- Give atropine for bradycardia.
Quick Reference: Pediatric Distributive Shock Management
| Step | Action | Key Considerations |
|---|---|---|
| 1 | Oxygen | 100% via non-rebreather, intubate if needed |
| 2 | IV/IO Access | IO if IV unsuccessful in 60–90 sec |
| 3 | Fluids: 20 mL/kg NS/LR | Repeat up to 60 mL/kg, reassess each time |
| 4 | Vasopressors | Norepinephrine (sepsis), Epinephrine (anaphylaxis), Dopamine (neurogenic) |
| 5 | Identify Cause | Antibiotics (sepsis), Epinephrine IM (anaphylaxis), Spinal precautions (neurogenic) |
When to Escalate Beyond Fluids
| Condition | Next Steps |
|---|---|
| Septic Shock | Start vasopressors, give antibiotics |
| Anaphylaxis | IV Epinephrine, steroids, antihistamines |
| Neurogenic Shock | Vasopressors + Atropine (if bradycardic) |
If worsening respiratory distress (stridor, wheezing, airway edema), intubate immediately.
Signs of Improvement After Treatment
- Heart rate normalizes
- Central pulses strengthen
- Warm extremities return
- Urine output >1 mL/kg/hr
- Mental status improves
If no improvement, escalate to advanced shock management protocols.
Summary: Why Early Distributive Shock Management Matters
- Start with fluid resuscitation, but don’t delay vasopressors if needed.
- Treat the underlying cause aggressively (infection, allergy, spinal trauma).
- Monitor vitals and perfusion closely to guide therapy.
Takeaway: Pediatric distributive shock progresses rapidly—early recognition, fluid resuscitation, and targeted interventions are critical to survival.