Excessive GI fluid loss can lead to a number of fluid, electrolyte, and acid-base imbalances. Here's a breakdown of those imbalances.
Fluid imbalances
- Hypovolemia and dehydration—large amounts of fluid can be lost during prolonged, uncorrected vomiting and diarrhea. Hypovolemia can also result if gastric and intestinal suctioning occur without proper monitoring of intake and output to make sure lost fluid and electrolytes are adequately replaced.
Electrolyte imbalances
- Hypokalemia—the excessive loss of gastric fluids rich in potassium can lead to hypokalemia.
- Hypomagnesemia—although gastric secretions contain little magnesium, several weeks of vomiting, diarrhea, or gastric suctioning can result in hypomagnesemia. Because hypomagnesemia itself can cause vomiting, the patient's condition may be self-perpetuating.
- Hyponatremia—prolonged vomiting, diarrhea, or gastric or intestinal suctioning can deplete the body's supply of sodium and lead to hyponatremia.
- Hypochloremia—any loss of gastric contents causes the loss of chloride. Prolonged gastric fluid loss can lead to hypochloremia.
Acid-base imbalances
- Metabolic acidosis—any condition that promotes intestinal fluid loss can result in metabolic acidosis. Intestinal fluid contains large amounts of bicarbonate. With the loss of bicarbonate, pH falls, creating an acidic condition.
- Metabolic alkalosis—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 also worsen the imbalance by adding to the alkalotic state.