Medical
Shock States & Hemodynamic Profiles
Distinguishing hypovolemic, cardiogenic, distributive, and obstructive shock by clinical findings and capillary refill patterns.
Four shock buckets
MedlinePlus defines shock as inadequate tissue perfusion—the body compensates with tachycardia and vasoconstriction before blood pressure falls.1 Hypovolemic shock from hemorrhage or dehydration shows flat neck veins, cool skin, and weak pulses. Cardiogenic shock from pump failure may show JVD, pulmonary edema, and narrow pulse pressure.
Distributive shock (septic, anaphylactic, neurogenic) features warm flushed skin early in sepsis or spinal injury, with vasodilation and relative hypovolemia. Obstructive shock from tension pneumothorax or massive PE shows obstructed venous return—JVD with hypotension and clear lungs in tension; acute right heart strain in massive PE.
Field identification and treatment alignment
The CDC sepsis campaign urges rapid recognition and treatment—EMS alerts for fever, tachycardia, and altered mental status shorten time to antibiotics.2 Anaphylactic distributive shock needs epinephrine IM first; cardiogenic shock may worsen with aggressive fluid boluses; obstructive shock from tension needs decompression before fluids.
Capnography EtCO₂ may be low in hypoperfusion. Lactate is hospital-side but clinical perfusion assessment drives prehospital priorities: stop bleeding, restore airway, decompress chest, epinephrine for anaphylaxis, norepinephrine or push-dose pressors per protocol when available. Reassess after each bolus or pressor—lung crackles may signal fluid overload in cardiogenic failure.
Practice this skill
Apply what you read with a hands-on Shock & Hemodynamics drill — instant feedback on every scenario.
