Whole-Bowel Irrigation 

Updated: Apr 07, 2020
Author: Rittirak Othong, MD, FACMT, FTCEP; Chief Editor: Vikram Kate, FRCS, MS, MBBS, PhD, FACS, FACG, FRCS(Edin), FRCS(Glasg), FIMSA, MAMS, MASCRS, FFST(Ed) 

Overview

Background

The rationale behind whole-bowel irrigation (WBI) is to prevent absorption of ingested matter (eg, extended-release medications or drug packets) by inducing a liquid stool through use of a osmotically balanced polyethylene glycol electrolyte solution (PEG-ES).[1, 2]

A study of acute-on-chronic lithium toxicity concluded that patients who received WBI within 12 hours of an acute overdose (compared with those receiving WBI >12 hours after the overdose) had reduced peak serum lithium concentrations, fewer intensive care unit (ICU) admissions, and a lower Poisoning Severity Score.[3] Early WBI as a means of gastrointestinal (GI) decontamination may lessen the need for more invasive treatment, such as hemodialysis in sustained-release lithium or potassium chloride overdose.[3, 4]

Administration of PEG-ES generally requires use of a nasogastric (NG) tube because of the large volume (>1 L in an average adult) that must be ingested over a short period. However, if insertion of an NG tube is difficult, an awake and alert patient may drink the solution instead.

WBI can also be used safely in pediatric patients, as revealed by a study of 176 patients ranging in age from 4 months to 12 years. Only minor adverse events (eg, abdominal bloating or vomiting) occurred, and no deaths were reported.[5]

In 2004, the American Academy of Clinical Toxicology (AACT) and the European Association of Poisons Centres and Clinical Toxicologists (EAPCCT) updated a position statement on WBI and other GI decontamination methods.[2] This statement, based on literature reviews and expert agreement, served as a guideline for the management of in-hospital poisoned patients. Because of the lack of controlled clinical trials showing that WBI improves clinical outcome, WBI was not recommended as a routine GI decontamination method for the poisoned patient. It should, however, be considered in certain situations (see Indications and Contraindications).[6]

PEG-ES may enhance tablet dissolution of non-sustained-release preparations. An in-vitro model study comparing dissolution rates of non-sustained-release acetaminophen demonstrated increased dissolution by PEG-ES in comparison with normal saline.[7]

In 2015, the AACT and EAPCCT conducted a systematic review on articles published from 2003 through 2013, using multiple databases to look for new data on WBI. They found no new evidence with sound methodology to change the 2004 recommendations; however, they did find more evidence on complications from WBI (see Technique, Complications).[8]

Indications

WBI may be considered in the following circumstances:

  • Prior to surgery, colonoscopy, or a barium enema to cleanse the bowel
  • Ingestion of a significant or life-threatening amount of sustained-release medications, [1, 2, 9, 10, 11] such as sustained-release potassium chloride [4]
  • Ingestion of a significant or life-threatening amount of medications or xenobiotics that are not adsorbed by activated charcoal (AC), [10] or a situation where no other GI decontamination methods are appropriate [1, 2] (eg, iron supplements, lead foreign body, [12]  or lithium [3] )
  • Ingestion of illicit drug packets [1, 2]
  • Ingestion of whole transdermal patches (eg, transdermal fentanyl patch or transdermal clonidine patch) [13, 14, 15]
  • Ingestion of multiple water beads with no signs of bowel obstruction [16]

Contraindications

Contraindications for WBI include the following:

  • Unprotected airway or compromised airway [1, 2]
  • Clinically significant GI bleeding [1, 2]
  • Intractable vomiting [1, 2]
  • Unstable vital signs [1, 2, 18]
  • Signs of leakage of illicit drug packets (eg, tachycardia, hypertension, hyperthermia in a patient who has ingested cocaine packets); a surgical consult should be obtained in this circumstance [1, 19]

Either WBI or single-dose AC (SDAC) is used for GI decontamination. Sometimes, WBI is used in conjunction with SDAC to enhance GI decontamination.

Many studies done with chlorpromazine,[20] fluoxetine,[21] theophylline,[22] cocaine,[23] and sustained-release preparations of carbamazepine[24] revealed that WBI decreased the efficacy of AC by increasing the rate of desorption of xenobiotics already attached to the AC when the two therapies were used simultaneously or when WBI was used shortly after AC.

Conversely, some studies demonstrated increased binding capacity of mexiletine and imipramine to charcoal when PEG-ES was added.[25, 26] SDAC administered with PEG-ES was also shown to significantly decrease the likelihood of seizures from venlafaxine overdose in comparison with WBI treatment alone.[27] WBI is not needed in cases where AC is known to adsorb the xenobiotic effectively; however, it may be considered as an adjunct measure in certain overdose situations.[8]

 

Periprocedural Care

Equipment

The materials required for whole-bowel irrigation (WBI) include the following:

  • 10% lidocaine solution (see the first image below)
  • 2% lidocaine jelly or KY jelly for lubrication (see the second image below)
  • Nasogastric (NG) tube of appropriate size (see the third image below)
  • Reservoir bag to hold irrigation polyethylene glycol electrolyte solution (PEG-ES; see the fourth image below)
  • PEG-ES (eg, GoLYTELY; see the fifth image below)
  • Intravenous (IV) pole on which to hang the bag of irrigation solution
  • Bedside commode (see the sixth image below)
10% lidocaine solution 10% lidocaine solution
2% Xylocaine jelly or KY jelly for lubrication 2% Xylocaine jelly or KY jelly for lubrication
Nasogastric tube. Nasogastric tube.
Nasogastric feeding bag (reservoir bag for the irr Nasogastric feeding bag (reservoir bag for the irrigation solution).
Polyethylene glycol electrolyte solution. Polyethylene glycol electrolyte solution.
Bedside commode. Bedside commode.

Patient Preparation

Anesthesia

Two studies, one involving 60 patients[28] and the other 206 patients,[29] demonstrated that the use of both lidocaine spray and lubricating jelly for the insertion of NG tubes was superior to the use of lubricating jelly alone. First, 1 mL of 10% lidocaine solution was sprayed into each nostril, in conjunction with 2 mL of 10% lidocaine solution sprayed into the back of the oropharynx. An NG tube was then lubricated with either lidocaine jelly or KY jelly.

These two simple steps significantly reduced patient pain, discomfort, and related adverse events (cough, epistaxis, chest pain, vomiting, shortness of breath, dizziness, and epigastric pain).[29] Moreover, the application of lidocaine spray before NG tube insertion increased both physicians' and nurses’ satisfaction during the procedures.[28, 29]

Positioning

A plain abdominal film should be obtained to confirm NG tube placement before the irrigation solution is administered. The patient should be comfortably seated on the bedside commode.

 

Technique

Whole-Bowel Irrigation

A nasogastric (NG) tube should be placed, especially in children, to ensure that an adequate amount of polyethylene glycol electrolyte solution (PEG-ES) has been administered.[5]  (See Nasogastric Intubation.)

If resistance is encountered during insertion of the NG tube, do not force insertion. The following tips may help with tube insertion:

  • Warm water may help soften the tip of the NG tube and thereby make insertion easier
  • Tying a knot at the tip of the NG tube (for ~5 minutes) helps create a curve that may make insertion easier; make sure to untie the knot before inserting the tube
  • Curve the tip of the NG tube, and place it in a cup of ice for several minutes; insert the stiffened NG tube with the tip initially pointed down; once the tip enters the oropharynx, rotate the NG tube 180° so that the tip now points posteriorly toward the esophagus

Once placement of the NG tube is confirmed, the PEG-ES can be administered. The solution is administered at a rate of 500 mL/hr in children aged 9 months to 6 years, 1000 mL/hr in children aged 6-12 years, and 1500-2000 mL/hr in adolescents and adults.[30]

A commode should be positioned by the patient's bedside, and the patient should be seated on it.

The entire procedure usually takes 4-6 hours. Patients often experience nausea and may vomit, in which case it may be necessary to slow the infusion rate. Alternatively, an antiemetic may be administered. The procedure is stopped once clear rectal effluent is seen or all drug packets have emerged.

The efficacy of whole-bowel irrigation (WBI) was not shown to be enhanced by pretreatment with an antiemetic in a study that compared two groups, one of which received 10 mg of oral metoclopramide 30 minutes before WBI, whereas the other received placebo.[31]

Complications

Potential complications of WBI include the following:

  • Nausea, vomiting
  • Mallory-Weiss tear and esophageal perforation associated with vomiting after ingestion of PEG-ES [32]
  • Abdominal bloating, cramps
  • Acute respiratory distress syndrome (ARDS) from aspiration of PEG-ES or misplacement of the NG tube [33, 34]
  • Organ injuries during NG tube insertion
  • Urticaria [35]
  • Angioedema of the lips [36]
  • Anaphylactoid reaction [37]
  • Death - This has been reported in an 86-year-old man who developed ARDS progressing to multiorgan failure after aspiration of PEG-ES [38]

The popular misconception notwithstanding, significant electrolyte abnormalities are not caused by WBI if PEG-ES is used as the solution.

An in-vitro study by Hodgman et al found that the use of PEG-ES for gastric decontamination after ingestion of extended-release morphine was not likely to accelerate the release of morphine and exacerbate intoxication.[39]