Low Blood Pressure (Hypotension) Slideshow Pictures Dehydration Slideshow Pictures

Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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The Arterial Wall

The space within the intravascular space is variable, based upon the muscle tension in the walls of the arteries. Adrenalin (epinephrine) increases tension and causes the arteries to narrow and support blood pressure. Acetylcholine dilates blood vessels and will lower pressure. Normally, the two are in balance.

• Loss of the sympathetic tone may occur with injuries to the spine and damage to the sympathetic trunk, resulting in dilation of the blood vessels and lowered blood pressure.
  
  
• Over stimulation of the vagus nerve can cause dilation of the blood vessels as well. A temporary, self-limiting situation called vasovagal syncope (passing out from low blood pressure due to overstimulation of the vagus nerve) is often seen when a patient receives a noxious stimulus. This can be physical, like a broken bone, or emotional like a medical student seeing their first operation.