Question for EMT's, nurses, or Doctors?
Answers: Depends, if this patients B/P is historically low. But assuming that you are asking because it is not; As an EMT I would look for any obvious signs such as major bleeding, allergic reaction, blunt trauma, etc. then ask about previous medical, specifically heart disease. Low BP can be cause by a number of things from dehydration to pericarditis.
Immediate treatment would be laying down, legs elevated if here was need for it. Basic hospital treatment would most promising be saline drip with a vasoconstricter.
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