Although gastric secretions contain little magnesium, several weeks of vomiting, diarrhea, or gastric suctioning can result in hypomagnesemia. Because hypomagnesemia can cause vomiting, the patient's condition may be self-perpetuating. Prolonged vomiting, diarrhea, or gastric or intestinal suctioning can deplete the body's supply of sodium and lead to hyponatremia. Any loss of gastric contents causes the loss of chloride. Prolonged gastric fluid loss can lead to hypochloremia.
Intestinal fluid contains large amounts of bicarbonate.
With the loss of bicarbonate, pH falls, creating an acidic condition. Loss of gastric fluids from vomiting or the use of drainage tubes in the upper GI tract can lead to metabolic alkalosis. Gastric fluids contain large amounts of acids that, when lost, lead to an increase in pH and alkalosis. Excessive use of antacids can worsen the imbalance. Treating GI fluid losses Treatment is aimed at the underlying cause of the imbalance to prevent further fluid and electrolyte loss.