Hypovolemic shock

• Hemorrhage
• Intravascular volume depletion (e.g., vomiting, diarrhea, ketoacidosis)
• Internal sequestration (ascites, pancreatitis, intestinal obstruction)

Cardiogenic shock

• Myopathic (acute MI, fulminant myocarditis)
• Mechanical (e.g., acute mitral regurgitation, ventricular septal defect, severe aortic stenosis, aortic dissection with aortic insufficiency)
• Arrhythmic

Extracardiac obstructive shock

• Pericardial tamponade
• Massive pulmonary embolism
• Tension pneumothorax

Distributive shock (profound decrease in systemic vascular tone)

• Sepsis
• Toxic overdoses
• Anaphylaxis
• Neurogenic (e.g., spinal cord injury)
• Endocrinologic (Addison's disease, myxedema)