Contrast Enema

Question 1

Indications for contrast enema

Answer 1

• Constipation, constipation, constipation, constipation (99% unremarkable other than you see constipation, a large-caliber colon, and usually a redundant sigmoid colon)
• r/o Hirschsprung disease (almost always negative, except in newborns)
• “r/o megarectum” or “r/o megacolon” (**no pedi data on what these are, so I will usually just give measurement and not call it megarectum/colon)
• r/o strictures/obstruction
• Intussusception Reduction: ONLY PERFORMED BY RADIOLOGIST; NOT IN OUR COLLABORATIVE AGREEMENT because these kids are extremely sick and there is a very high-risk of perforation and/or more severe outcomes (patients have coded on the table)

Question 2

Contrast used for contrast enema

Answer 2

ALWAYS WATER-SOLUBLE, NEVER BARIUM, NO AIR
- Cystografin, CystoConray II, Omni 300 non-diluted (usually for the tiny NICU babies)
- Very rarely there will be orders for a Gastrografin therapeutic enema. There is a dilution protocol—ask radiologist which one he/she would like to use. Radiology lead tech has the protocol.

Question 3

Table position/machine settings for contrast enema

Answer 3

• 3 p/s, 0.5 f/s
• Horizontal
• Tech will take scout image and then tip the patient and secure tip with a lot of tape. NICU different specifics
• Start LEFT LATERAL—save cine loops until sigmoid colon is filled; most critical images here to eval the rectosigmoid ratio (r/o Hirschsprung)
  Tip: when I see something that looks concerning for Hirschsprung, I will take an exposure image here. Otherwise, no exposure.
  Fill to splenic flexure
• LPO (optional) for a quick last-image hold
• SUPINE to fill transverse and descending colon to cecum
• RARELY will turn patient RIGHT LATERAL if having trouble filling the ascending colon—this is very challenging to do with kids because of the way the tip is taped, so I try my best to avoid it
• Last-image hold with colon full
  You can leave the room here and the techs will do the rest
  Left lateral to drain contrast by gravity. Techs will then remove tip, allow pt to use the toilet (if old enough—if not, can stop here)
  Tech will take a post-evac image

Question 4

How to do contrast enema for NICU/young infant babies

Answer 4

Usually up to 4-6 months, use judgement
In the NICU babies, when there is a concern for a small bowel obstruction but no work-up has been done, they will almost always start with an enema (and likely follow with an UGI/SBFT once the contrast has cleared 24-48 hrs later). This is a common request.
- Colon is usually small in babies with SB obstruction
- If you see Hirschsprung, it will usually be in the newborns who have not passed meconium/stooled since birth. Make sure to get really good LEFT LATERAL early fill images (cine loop) here.
- Use Omni 300 for NICU babies (if out of Omni ok to use Cysto), no dilution
These are ALWAYS messy, many times the techs can’t maintain the seal (because it’s hard) and contrast will leak out and you just have to breathe and start over
- You will then use a foley catheter as your tip (anything from 10 Fr to 20 Fr, most will be 12 Fr-14 Fr)
Do NOT inflate the balloon
Want your distal tip to be just in the most distal rectum
- The techs will then squeeze the buttocks to hold the catheter in place. Using tape with babies is not recommended due to sensitive skin. You will get the techs’ hands in the picture—it is what it is.
Let parents know the bottom will be bruised/red and that’s just from us holding it. It’ll pass.
- Gently HAND INJECT contrast. Techs are not supposed to hand inject contrast due to risk of perforation. Don’t let them even if they offer
- Fill to cecum, try to reflux into the distal small bowel if able
- When done, try to pull back as much contrast as possible, then once foley is removed they will usually squirt a bunch of stool/meconium/mucus out