RECOGNITION OF SHOCK IN PEDIATRIC PATIENTS

Shock occurs when oxygen delivery to tissues is insufficient to meet metabolic demands, leading to organ dysfunction and potential failure. Pediatric patients compensate well initially, but once they decompensate, deterioration is rapid. Early recognition and intervention are critical to prevent irreversible damage or cardiac arrest.

Key Goals in Pediatric Shock Management:
Identify the type of shock early based on clinical presentation.
Initiate appropriate resuscitation (fluids, vasopressors, inotropes).
Prevent progression to decompensated shock and cardiac arrest.

TYPES OF SHOCK & KEY FEATURES

Pediatric shock is classified into three main types, each with distinct causes and clinical signs:

Key Differentiator:

• Hypovolemic & Cardiogenic Shock = Cold extremities.
• Distributive Shock (Septic, Anaphylactic, Neurogenic) = Warm extremities (early).

HYPOVOLEMIC SHOCK

Definition: Shock caused by decreased intravascular volume, leading to inadequate preload, stroke volume, and cardiac output.

Common Causes:
Dehydration (e.g., gastroenteritis, vomiting, diarrhea).
Hemorrhage (e.g., trauma, GI bleeding, postpartum hemorrhage).
Burns (fluid loss due to skin barrier disruption).
DKA (Diabetic Ketoacidosis) – excessive fluid losses.

Key Signs of Hypovolemic Shock:
Compensated Stage (Early Signs):

• Tachycardia (earliest sign).
• Weak peripheral pulses, but strong central pulses.
• Cool extremities, delayed capillary refill (>3 sec).
• Decreased urine output (<1 mL/kg/hr).
• Dry mucous membranes, sunken fontanelle (infants).

Decompensated Stage (Late Signs, Pre-Arrest):

• Hypotension (late and ominous sign in children!).
• Severe mental status changes (lethargy, unresponsiveness).
• No urine output (anuria).

Treatment Approach:
Fluid Resuscitation:

• 20 mL/kg IV bolus of isotonic fluid (NS or LR) over 5-10 minutes.
• Repeat as needed up to 60 mL/kg, then reassess.
  Correct Underlying Cause:
• Control bleeding if hemorrhagic shock.
• Rehydrate if due to dehydration (add dextrose if hypoglycemia).
  Monitor for Fluid Overload:
• If signs of pulmonary edema develop, suspect cardiogenic shock instead.

DISTRIBUTIVE SHOCK

Definition: Shock caused by abnormal vasodilation and redistribution of blood flow, leading to relative hypovolemia and poor organ perfusion.

Common Causes:
Septic Shock (most common) – bacterial infection causing systemic inflammation and vasodilation.
Anaphylactic Shock – severe allergic reaction leading to vasodilation and airway compromise.
Neurogenic Shock – spinal cord injury causing loss of sympathetic tone.

Key Signs of Distributive Shock:

Early Septic Shock (Warm Phase)

• Tachycardia.
• Bounding peripheral pulses.
• Warm extremities, flushed skin.
• Widened pulse pressure (low diastolic BP).

Late Septic Shock (Cold Phase, Decompensated)

• Cold extremities, delayed capillary refill.
• Weak pulses, hypotension.
• Altered mental status (lethargy, unresponsiveness).

Treatment Approach:
Aggressive Fluid Resuscitation:

• 20 mL/kg IV bolus of isotonic fluid (NS or LR) over 5-10 minutes.
• Repeat up to 60 mL/kg, then reassess.
  Vasopressor Support:
• Epinephrine (for anaphylaxis).
• Norepinephrine or epinephrine (for septic shock after fluids).
  Treat Underlying Cause:
• Sepsis → Start broad-spectrum antibiotics (within 1 hour).
• Anaphylaxis → IM epinephrine, antihistamines, steroids.

CARDIOGENIC SHOCK

Definition: Shock caused by impaired heart function, leading to inadequate cardiac output and tissue perfusion.

Common Causes:
Congenital heart disease (e.g., ductal-dependent lesions).
Myocarditis (viral infection of the heart muscle).
Arrhythmias (SVT, complete heart block).
Severe heart failure (e.g., cardiomyopathy, Kawasaki disease).

Key Signs of Cardiogenic Shock:
Symptoms Suggesting a Cardiac Origin:

• Tachycardia (often severe).
• Weak pulses, cool extremities.
• Hepatomegaly (sign of right heart failure).
• Pulmonary edema (crackles, respiratory distress).
• JVD (jugular venous distension, in older children).

Signs That Differentiate Cardiogenic from Hypovolemic Shock:

• Pulmonary edema → Fluid resuscitation may worsen symptoms!
• Hepatomegaly → Suggests fluid overload rather than depletion.
• Worsening with aggressive fluids → May need inotropes instead.

Treatment Approach:
Avoid Large Fluid Boluses (Risk of Fluid Overload!).
Use Inotropes to Improve Cardiac Output:

• Epinephrine (if cold shock, low cardiac output).
• Dopamine or Dobutamine for cardiac dysfunction.
  Treat the Underlying Cause:
• Arrhythmias → Consider adenosine (SVT) or synchronized cardioversion.
• Ductal-dependent lesions → Start prostaglandin E1 (PGE1).

DIFFERENTIATING SHOCK TYPES: QUICK REFERENCE

SUMMARY: WHY EARLY SHOCK RECOGNITION MATTERS

Tachycardia is often the first sign of shock in children.
Hypotension is a late and life-threatening sign—treat shock before it occurs!
Fluid resuscitation is key for hypovolemic and distributive shock, but harmful in cardiogenic shock.
Identify the type of shock early to guide appropriate treatment.

Takeaway: Pediatric shock progresses rapidly—early recognition and intervention are critical to survival.