Colonoscopy preparations: electrolyte imbalances and precautions in the fragile patients

Abstract

Bowel preparation intake for colonoscopy can cause electrolyte imbalances. Although it is a rare complication, occurs as a consequence of the loss of electrolytes and water into the intestinal lumen, and because some electrolytes from the preparations can be absorbed. The possible imbalances cover all the alterations range of the internal environment (hypo and hypernatremia, hypo and hyperkalemia, metabolic acidosis, hypocalcaemia, and hyperphosphataemia or hypermagnesaemia). Electrolyte disturbances and their severity depend on electrolyte content of the preparation solution, the fluid replenishment conducted, and patient characteristics.

Electrolyte imbalances are generally transient, and these should not cause complications if adequate fluid replenishment with or without electrolytes during bowel preparation is conducted and maintained over time once the colonoscopy is performed. We reviewed the most frequent electrolyte imbalances that occur with the most used bowel cleansing preparations and precautions to be taken into consideration in fragile patients.

Keywords: colonoscopy, bowel preparations, hyponatremia, hypernatremia, hypermagnesaemia.