Nelson Textbook of Pediatrics 22nd Edition — Chapter 85 | Hypovolemic, Cardiogenic, Distributive (Septic, Anaphylactic, Neurogenic), Obstructive, and Dissociative Shock. Pathophysiology, clinical features, examples, and treatment.
🌐 paeds.online — Pakistan's Pediatric Platform| Type of Shock | Pathophysiology | Clinical Appearance | Examples | Treatment |
|---|---|---|---|---|
| Hypovolemic | Decreased cardiac output due to volume depletion (↓ preload) | Tachycardia, vasoconstriction, delayed capillary refill, cool extremities, orthostatic changes, late hypotension | Non-hemorrhagic: vomiting, diarrhea, dehydration; Hemorrhagic: trauma, GI bleeding | IV fluid bolus 20 mL/kg crystalloid; for hemorrhagic: blood transfusion |
| Cardiogenic | Decreased cardiac output due to myocardial dysfunction (↓ contractility, ↑ afterload) | Tachycardia, vasoconstriction, cool extremities, narrow pulse pressure, rales, gallop rhythm, hepatomegaly | Myocarditis, cardiomyopathy, congenital heart disease, post-cardiac surgery, arrhythmias | Judicious IV fluids, inotropes (epinephrine, milrinone), afterload reduction, treat arrhythmias |
| Distributive | Decreased SVR (vasodilation), maldistribution of blood flow, relative hypovolemia | Warm, flushed extremities, bounding pulses, wide pulse pressure, flash capillary refill (early); may become cold if myocardial dysfunction | Septic shock, anaphylaxis, neurogenic shock (spinal cord injury), toxic shock | IV fluids, vasopressors (norepinephrine for warm shock; epinephrine for cold shock), treat underlying cause |
| Obstructive | Decreased cardiac output due to mechanical obstruction to blood flow (↑ afterload) | Tachycardia, cool extremities, narrow pulse pressure, JVD, distant heart sounds (tamponade), asymmetric breath sounds (pneumothorax) | Tension pneumothorax, cardiac tamponade, pulmonary embolism, ductal-dependent congenital heart disease | Needle decompression (tension pneumothorax), pericardiocentesis (tamponade), thrombolytics/embolectomy (PE), prostaglandin E1 (ductal-dependent lesions) |
| Dissociative | Inadequate oxygen delivery despite normal or high cardiac output (impaired oxygen-carrying capacity or utilization) | Tachycardia, ± delayed capillary refill, pallor, weakness; may have normal perfusion but hypoxemia or metabolic acidosis | Severe anemia, carbon monoxide poisoning, methemoglobinemia, cyanide poisoning, thiamine deficiency | Transfusion (anemia), 100% oxygen/hyperbaric (CO), methylene blue (methemoglobinemia), hydroxocobalamin (cyanide) |