A young woman is brought to the emergency department by ambulance after a severe motor vehicle accident. She is unconscious. Her blood pressure is 64/40 mm Hg; heart rate is 150 bpm. She is intubated...

A young woman is brought to the emergency department by ambulance after a severe motor vehicle accident. She is unconscious. Her blood pressure is 64/40 mm Hg; heart rate is 150 bpm. She is intubated and is being hand-ventilated. There is no evidence of head trauma. The pupils are 2 mm and reactive. She withdraws to pain. Cardiac examination reveals no murmurs, gallops, or rubs. The lungs are clear to auscultation. The abdomen is tense, with decreased bowel sounds. The extremities are cool and clammy, with thready pulses. Despite aggressive blood and fluid resuscitation, the patient dies.

Questions

1. 
   A. What are the four major pathophysiologic causes of shock? Which was likely in this patient?


2. 
   B. What pathogenetic mechanism accounts for this patient’s unresponsiveness? For the cool, paleextremities?

1. 
   C. What forms of hypovolemic shock may have been present in this patient? Why?