Physiological Effects of Acute Blood and Fluid Loss

Pathophysiology of Hypovolemic Shock

Hypovolemic shock occurs due to a severe reduction in blood volume, leading to inadequate tissue perfusion and oxygenation. This condition can be caused by hemorrhage, dehydration, or fluid sequestration.

Mechanisms of Hypovolemia

• Loss of circulating volume: Decreased venous return reduces cardiac output.
• Compensatory mechanisms: Activation of the sympathetic nervous system increases heart rate and vasoconstriction.
• Cellular metabolism disruption: Insufficient oxygen delivery leads to anaerobic metabolism and lactic acidosis.

Clinical Manifestations

• Tachycardia and hypotension
• Cold, clammy skin due to vasoconstriction
• Altered mental status from cerebral hypoxia

Stages of Hypovolemic Shock

Shock progresses through compensated, decompensated, and irreversible phases, each requiring different medical interventions.

Treatment Approaches

Management includes rapid fluid resuscitation, blood transfusions, and addressing the underlying cause to restore circulatory stability.