From the Guidelines
Whole bowel irrigation with polyethylene glycol (PEG) preparation is primarily used for bowel cleansing prior to colonoscopy or other medical procedures, and its purpose is to mechanically cleanse the gastrointestinal tract through its osmotic properties. The solution contains balanced electrolytes to prevent significant fluid and electrolyte shifts during administration, making it a preferred choice for patients who are less likely to tolerate fluid shifts, including those with renal insufficiency, congestive heart failure, and advanced liver disease 1. Key points to consider when using PEG preparation include:
- The use of reduced-volume, FDA-approved PEG-ELS formulations to improve tolerance 1
- The administration of PEG solution at a rate of 1-2 L/hour for adults, typically via nasogastric tube until rectal effluent is clear or for 4-6 hours 1
- Contraindications such as bowel obstruction, perforation, ileus, hemodynamic instability, and unprotected airways
- Side effects including nausea, vomiting, abdominal discomfort, and bloating According to the most recent guidelines, polyethylene glycol preparation is recommended as a preferred solution for bowel lavage 1, and its use is supported by evidence from multiple studies, including a 2014 study published in Gastroenterology that compared high-volume PEG-ELS with low-volume PEG-ELS and found no significant difference in bowel cleanliness, but did find that a split-dose regimen of PEG-ELS significantly increased cleanliness compared to a non-split dose regimen 1.
From the Research
Purpose of Whole Bowel Irrigation with Polyethylene Glycol (PEG) Preparation
The purpose of whole bowel irrigation with polyethylene glycol (PEG) preparation is to:
- Remove toxic substances from the gastrointestinal tract [(2,3)]
- Prevent absorption of toxic compounds 2
- Serve as a decontamination procedure after acute drug overdose 3
Mechanism and Efficacy
- Whole bowel irrigation with PEG electrolyte lavage solution has been shown to decrease the absorption of toxic substances, such as ampicillin, by 67% 3
- The procedure involves the administration of a large volume of PEG electrolyte lavage solution, which can be safely tolerated by patients [(3,4)]
- The solution helps to flush out the toxic substances from the gastrointestinal tract, reducing the risk of further absorption [(3,4)]
Interaction with Activated Charcoal
- Whole bowel irrigation solution can interact with activated charcoal, reducing its adsorptive capacity for certain toxic substances, such as theophylline [(5,6)]
- This interaction can decrease the efficacy of activated charcoal in adsorbing toxic substances, highlighting the need for careful consideration when using both treatments concurrently [(5,6)]