What are the common gastrointestinal causes of hypovolemia?
• Gastrointestinal bleeding is a common cause of volume contraction.
• Loss of fluid from the gastrointestinal tract can cause volume contraction. Secretions from the stomach, pancreas, gallbladder, and intestines total about 3 to 6 L/day, but almost all of this secreted fluid is reabsorbed. If reabsorption is prevented because of vomiting or external drainage of secretions (as with tube drainage or ostomies), volume contraction can ensue. If secretions increase (as with diarrhea), volume contraction can ensue.
