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Mismatch between intravascular volume and blood pressure |
States in which blood pressure is not primarily determined by intravascular volume |
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Intravascular volume low Blood pressure high | Vasoconstriction |
(i) Stimulants (cocaine, amphetamines), catecholamines (pheochromocytoma, severe stress, delirium tremens) |
(ii) Severe hypothyroidism |
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Intravascular volume high Blood pressure low | Cardiac dysfunction |
(i) Cardiogenic shock |
(ii) Severe cardiomyopathy, heart failure, valvular heart disease |
Vasodilation |
(i) Distributive shock + excess volume resuscitation |
(ii) Autonomic neuropathy |
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Mismatch between intravascular and extravascular volume |
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Intravascular volume low Extravascular volume high | Vasodilation and/or “third spacing” |
(i) Distributive shock (sepsis, anaphylaxis) |
(ii) Hemorrhagic pancreatitis |
(iii) Crush injury |
Delayed reequilibration |
(i) Severe renal failure + diuresis or ultrafiltration |
(ii) Nephrotic syndrome + diuresis |
(iii) End-stage liver disease + diuresis or large volume paracentesis or ultrafiltration |
(iv) Heart failure + diuresis or ultrafiltration |
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Intravascular volume high, Extravascular volume not high | Delayed reequilibration |
(i) Rapid blood transfusion + anuria or severe renal failure |
(ii) Rapid hypertonic sodium bicarbonate or saline infusion |
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