hypovolemic shock

Introduction

Shock resulting from loss of >20% of the circulating blood volume.

Etiology

• hemorrhage
• dehydration
• hypoadrenal (Addisonian) crisis

Pathology

• decreased central venous pressure (CVP)
• low cardiac filling pressures
• low cardiac output
• compensatory increase in systemic vascular resistance

Clinical manifestations

• hypotension generally manifests when > 30% of blood volume is lost
• more sensitive indicators of impending shock include:
  • anxiety
  • tachypnea
  • weak peripheral pulse
  • cool extremities with pale or mottled skin

Complications

• coagulopathy
  • hypercoagulable state with fibrinolysis shutdown
  • dilutional coagulopathy due to crystalloid infusion

Management

• general strategies
  • rapid volume expansion
    • intravenous (IV) fluids
    • colloid
    • blood products
    • prehospital plasma transfusion lowers mortality in unstable trauma patients transported by air
  • consider hemodynamic monitoring if coexisting medical problems
    • congestive heart failure
    • valvular heart disease
    • myocardial ischemia
    • renal insufficiency
• specific strategies
  • correct coagulopathy & thrombocytopenia
  • correct electrolyte imbalances
  • endoscopy
  • interventional radiology
  • surgery
  • REBOA for pelvic or abdominal bleeding
• avoid vasopressor use in hemorrhagic shock

More general terms

• hypovolemia (extracellular volume depletion)
• shock

More specific terms

• hypoadrenal (Addisonian) crisis; acute adrenal insufficiency