Background

Among the various methods used to prevent overdoses, whole-bowel irrigation (WBI) is a technique used to prevent the absorption of ingested substances by inducing a liquid stool with a polyethylene glycol electrolyte solution (PEG-ES). The researchers have already demonstrated the ability of a WBI patient to reduce the peak serum lithium concentrations within 12 hours of an overdose, to keep the ICU admissions at minimum, and the Poisoning Severity Score dropped off by some points. Treatments such as hemodialysis can be avoided in case of sustained-release lithium or potassium chloride overdose if WBI is taken at an early stage.  On the other hand, WBI can be safely administered to the younger patients with few cases of side effects being reported.  

While WBI is not recommended routinely as a method of GI decontamination for poisoned patients, some situations need to be taken into consideration. 

Indications

This procedure is considered in the following: 

1. Before operation, colonoscopy, or a barium enema to clear the bowel 
2. Accidental intake of a life-threatening dose of drugs such as a sustained-release form of medication like potassium chloride which may harm the heart slowly because of its low absorption rate could induce severe or even fatal toxic poisoning in patients. 
3. Induction of a pernicious or life-threatening measure of medicines or xenobiotics which are not adsorbed by AC (activated charcoal) in the stomach of a patient, as well as a condition when there is no other way of removing the drugs from the digestive tract than using the GI decontamination methods (eg, iron supplements, lead foreign body,  or lithium. 
4. Drug carrying by water beads with no symptoms of blockage. 
5. Hypertrophic pyloric stenosis with pharmacobezoar formation identified on abdominal 

Contraindications

These include: 

Compromised or unprotected airway 

Intractable vomiting 

Ileus, perforation, or bowel obstruction 

Unstable vital signs 

Significant gastrointestinal bleeding 

Signs of hyperthermia, tachycardia, hypotension 

Outcomes

Factors that affect the outcome of whole-bowel irrigation includes the time of initiation, the type and toxicity of ingested substance, effectiveness of removal of toxin, general health consitio of patient and concurrent medical interventions. If initiated early, the prognosis can be more favourable. Other factors which would decide this are the nature and concentration of the substance. Variables associated with with the efficacy of removal of toxin include factors like the adequacy of bowel preparation, type of cathartic used, and total volume administered.  

Equipment

Following materials are required for WBI: 

1. 10% lidocaine solution 
2. 2% KY jelly or lidocaine jelly for lubrication 
3. Reservoir bag for holding irrigation PEG-ES  
4. Nasogastric tube or required size 
5. Intravenous pole for hanging irrigation solution bag 

Patient preparation

Anesthesia 

The combined use of lidocaine spray and lubricating jelly into catheter injection through the nose was found to be efficient and less painful compared to the use of lubricating jelly alone. The combination also reduced any pain, distress or injury from occurring to the patient while at the same time improving the satisfaction of the physicians and nurses during the process. Most importantly, it was advised that the medicated lube should be adopted. 

Patient position

A plain abdominal film should be done to verify NG tube placement before commencement of the irrigating solution. The patient must be in a comfortable sitting position on a bedside commode. 

Technical considerations

The nasogastric tube is inserted with the help of PEG-ES (polyethylene glycol electrolyte solution) used for children so that the liquid substance should be given through the nasogastric tube or larynx. Do not apply it with force if it sticks during the process of inserting inside. A patient toilet should be put by his bed and the patient be sitting comfortably. The whole process generally takes 4-6 hours. Patients usually feel sick, so it can occur that they are sick in this case, and in this scenario, it may be necessary to slow the infusion rate. Alternatively, can be an antiemetic given. The method should be terminated, when there is a colourless rectal effluent or if all drug packets have been expelled. 

The study that compared two groups, one of which received 10 mg of oral metoclopramide 30 minutes before WBI and the other took a placebo, showed that whole-bowel irrigation (WBI) was not found to be more effective when the subjects were given antiemetic drugs before the procedure. 

Complications

Mallory-Weiss tear 

Esophageal perforation 

Urticaria 

Severe immediate hypersensitivity 

Organ injuries during the insertion of NG tube 

Angiodema of lips 

Abdominal bloating 

Abdominal cramps 

ARDS (acute respiratory distress syndrome) 

Nausea 

Vomiting 

Death 

References

Position-Statement-Whole-Bowel-Irrigation-1.pdf (clintox.org) 

References

Position-Statement-Whole-Bowel-Irrigation-1.pdf (clintox.org)