Mannitol as Oral Contrast for CT abdomen- a Cost effective CT Enterography agent
Teaching Points on CT Enterography by Dr MGK Murthy, MD, DNB
1. Practice of Positive Oral contrast (Iodine based like Urograffin) is being replaced by Negative/Neutral contrast agents including water with or without mannitol addition(for small bowel distension). 100 ml bottles of Mannitol 20%(Weight by volume) are popular as single patient use . Please carefully open the seal and add drinking water to make the total volume to 2000 ml (i.e. approximately about 1900 ml added ). Administer 1300ml out of this slowly over 50 minutes to an hour duration, before taking up the patient .Give an additional 200 ml (Total consumption would be 1500ml) before starting the scan ,on the table , to augment distension of stomach/duodenum. (balance amount of 200 ml to be discarded)
2. In CT - PET scan, this drinking may mildly activate the increased pharyngeal uptake of FDG , which however does not pose any significant diagnostic difficulty .
3. If a patient is on" NIL orally" instructions with stomach tube - NO ORAL CONTRAST is the rule. In case of very Critically ill patients/ Very elderly (usually above 75 yrs +)/ haemodynamically compromised patients (particularly on dialysis or acute cardiac patients etc ) or small babies (usually below 5 years) and PREGNANT (of course we should be avoiding abdominal CT), use your discretion based on Individual needs.
4. In case of any doubt, Plain drinking water is most non controversial (non distending )oral negative agent Administration of IV buscopan is preferred if Enterography is needed rather than routine Abdominal CT
5. Small bowel CT Enterography with oral mannitol and IV buscopan is gradually replacing Enteroclysis
Mannitol as Oral Contrast for CT abdomen- a Cost effective CT Enterography agent Reviewed by Sumer Sethi on Wednesday, December 03, 2014 Rating: