Feb 3, 2012
1. Polyethylene glycol (PEG) 17g/1 glass per day. Up to 3 doses daily if needed
2. PEG + fecal inotrope/stimulant. Senna first choice
3. Docusate + Senna
Docusate alone is probably not sufficient to prevent constipation in a patient on narcotics. The problem with narcotics is that they slow gut motility. Docusate works by breaking down fats, making stool soft/slick and also works as a weak osmotic laxative. This creates a soft stool that is still sitting in the colon. It's like a fast car propped up on cinderblocks. If docusate is used in combination with a stimulant like senna, laxation improves significantly.
Warning: Bulking agents are often recommended as constipation prophylaxis for patients on narcotics. This may expand the diameter of the colonic lumen without moving anything though.
Step 1. Manually disimpact if needed and place an enema in the ED.
Step 2. 2mg PO naloxone before ED discharge
Step 3. Disimpaction dose of PEG (1.5g/kg/day or easy dosing 4 glasses per day). Take for 6 days or until soft stool passes, whichever comes first
Step 4. Maintenance PEG. (0.3-0.8g/kg/day or easy dosing 1 glass per day). Take for 2 weeks and slowly taper
Choice 1. Bulking agent like methylcellulose or psyllium. Must drink at least 1.5 liters of water per day, or the stool will become a colon shaped piece of concrete.
Choice 2. Docusate
1. I will often place a saline enema while the patient is in the ED.
2. Another option in the ED, especially for younger kids who may not be able to hold in an enema, is a glycerin suppository. Glycerin softens stool and makes the passageway slick, but more importantly, acts as a stimulant and increases intestinal propulsion. See The Suppository Conundrum for details on how to place an suppository.
3. Outpatient treatment: PEG disimpaction dose (1.5g/kg/day) for 6 days or until soft stool passes, followed by a maintenance dose of 0.3-0.8g/kg/day for two weeks followed by a slow taper
4. Lactulose also a laxative option
5. Stress a diet with lots of fiber and water
6. Don’t hold it in Kids should defecate when the urge strikes. Waiting may make the urge pass with the result being a harder, drier, more impacted stool. Then, like an overdue baby, it won’t want to leave its happy home. Kids will keep playing rather than going to the bathroom, and some have angst with pooping so they hold it in. We need to talk to our patients/parents about this.
Mineral oil makes the stool slick and soft so it passes easier. In the studies and reviews I’ve read, the recurrent theme is that it shouldn’t be given in infants or long term use because of complications like aspiration, lipoid pneumonia and foreign body reaction in gut. The toxicity is increased if it’s given along with docusate. The risk/reward analysis does not favor mineral oil. Bottom line: there are better agents out there. If you really want to get mineral oil into the colon, give it as an enema.
Below is Whit Fisher's famous Disimpaction Action video. One thing I do differently than Whit is that I don't tape my wrists (you'll know what this means after watching the video). I realize the risk of 'debris' getting up the sleeve, but there is often need to remove the outer glove during or after the procedure. Also, I don't want to unwind tape around my wrists using a glove smeared with fecal matter, which is inevitable in this procedure. Enjoy.
Joe Lex - Free Emergency Medicine Talks
Andy Sloas - PEM ED podcast
Procedurettes by Whit Fisher, MD