After a consult/recommendation with nutritional medicine, your student wants to start a 68 y/o elderly patient with some mild senile dementia on "tube feeds" via a nasogastric tube because her current calorie and protein intake were not meeting her needs. Because of her age and concurrent medical conditions, the student wants a small amount of blue dye placed in the tube feeds in order to more easily detect aspiration.

Do you concur with the blue dye in the tube feeds? Why or why not?
 

** THANKS to Dr Kelli Sorrels (pharmacy), LTC Sharon Hunter, CAPT James
Weinstein and CAPT Denise Lockhart (Nutritional medicine) for their help
with this Pearl. **

No. Do not add the blue dye to the tube feeding. Although initially thought to be without risk and a reasonable indicator of aspiration, the nutritional support community advises AGAINST putting blue dye into tube feeds. Blue dye was thought to be non-absorbable, non-toxic, and sensitive for aspiration.

There are 4 reviews of cases/patients receiving tube feeds with blue dye in them. Two died but it's unclear whether it was directly due to the blue dye or their underlying conditions. Both these patients experienced skin and/or body organ staining. (I can send some ugly post mortem pictures if you're interested)

Both ASPEN (American Society of Parenteral and Enteral Nutrition) and an article published in the Journal of Parenteral and Enteral Nutrition recommend against the use of blue dye in tube feeds. These publications state 1) the reliability and validity have not been adequately tested, 2) there have been reports of skin and body organ staining, and 3) no safe amount of dye has been established. The case reports hypothesize the blue dye is absorbed due to increased intestinal permeability and the blue dye
can cause decreased mitochondrial oxygen consumption and mitochondrial toxicity.

Since blue dye is NOT recommended to routinely detect aspiration, prevention is the best treatment. Prevention may include: 1) adjusting rate of administration based on tolerance, bowel sounds, and residuals 2) elevating the head of bed 45 degrees or more, 3) pro-motility agents.

From a review done by Nutritional Medicine:

Aspiration of gastric contents is common in enterally fed patients.  Some believe adding coloration to tube feedings helps identify gastric aspiration.  Multiple sources using strong research methods have shown this method of dying tube feedings to identify potential gastric aspirates is NOT a sensitive method for detection of aspiration.  There are a number of reports of absorption of blue dye from enteral feeding in critically ill patients with sepsis. FD&C No. 1 and similar dyes have toxic effects on mitochondria1 ... this is a direct link to the potential harmful nature of the dye in use.

Conclusion: blue dye in enteral feedings should be abandoned and replaced by evidence based methods for the prevention of aspiration2.

Facts:

1)    Blue dyes are thought to be a good indicator for aspiration since blue is not a color found in secretions.  Some hospitals use methylene blue, a widely available drug not approved for use in food3.  Methylene blue may cause hemolytic anemia and is fairly expensive4.

2)    Blue Dye use is a poor method for determining aspiration.  There is no gold standard to define aspiration.  Some say that aspiration is defined through clinical impression, others define it as blue dye in the ET tube, others say is requires a detection of glucose from the tube feeding in the ET tube.  The Blue Dye (BD) method has been compared to the Glucose Detection (GT) method by a number of authors and found to be one of the least effective methods of recognizing gastric aspirates in the ET tube5-8.

3)    Case Reports of Dye absorption form enteral feedings is the main concern as this dye absorption has been associated with Death in 4 different reports2, 9-11.

Alternate methods to detect and prevent aspiration include-in order of effectiveness: 1) Head of Bed above 45 degrees, 2) Use of an agent to increase gastric emptying and or placement of the feeding tube beyond the pyloris and preferably beyond the Ligament of Trietz. 

REFERENCE:

- Maloney JP and Tracey RA.  Detection of Aspiration in Enterally Fed Patients:  A Requiem for Bedside Monitors of Aspiration.  JPEN2002;26:S34-411

- ASPEN Nutrition Support Practice Manual '98
 

This Pearl is meant for academic and educational purposes only. This Pearl is meant to raise important points regarding the safe and cost-effective pharmacotherapy of patients. It is not meant to be the definitive reference for the treatment or prophylaxis of various diseases. Although every effort is taken to ensure this Pearl is correct and factual, errors may occur. The Pharmacoeconomic Center assumes no liability for incorrect information or harm that may occur from the use of the information included in this Pearl.