In a patient with a suspected gastrointestinal bleed, which sign would most strongly indicate hypovolemic shock?

• A. High blood pressure
• B. Low blood pressure
• C. Normal pressure
• D. Hypertension

Answer: (B)

Hypovolemic shock from a GI bleed happens when a significant loss of blood reduces the circulating volume, which lowers venous return and preload. That drop in preload makes the heart pump less effectively, decreasing cardiac output and tissue perfusion. The body may try to compensate with faster heart rate and vasoconstriction, which can keep blood pressure normal early on, but as the volume loss continues, blood pressure falls. A low blood pressure is the clearest sign that perfusion is severely compromised and shock is developing. High blood pressure or normal pressure don’t reflect the reduced circulating volume and perfusion, so they’re not indicators of hypovolemic shock.