Food (and the eating of it) plays a central role in our experience of health and illness. Think of whatever the latest health food craze is, or a parent feeding chicken soup to a sick child. Many acute and chronic medical conditions alter a person's natural ability to ingest, absorb, or use use the nutrients contained in food. When this happens, there are medical interventions that can deliver nutrients into the GI tract via a tube (enteral nutrition) or directly into the veins (parenteral nutrition). We as physicians and other members of the healthcare team often offer artificial nutrition reflexively and do not have extensive discussions about the expected benefits, risks, and goals of artificial nutrition before make the recommendation to begin it. Artificial nutrition is a form of life support and is not right for everybody, either because it will not help them get better or because they have expressed a wish to not have their life prolonged by artificial means. Therefore, a situation where artificial nutrition is considered should be seen as a time to pause and consider the medical team's goals of that medical intervention and whether it is in line with the patient's values and goals.
Because the situation is not as simple as "can't eat, so feed artificially," I propose the "5 D's" as a way to critically appraise a situation where artificial nutrition is being consider. The first four D's represent four buckets, or groupings, into which the many causes of malnutrition can be grouped. While perhaps a bit over-simplistic, this should help you consider the reason WHY artificial nutrition is considered and therefore guide discussions and literature searches about the utility of artificial nutrition in that situation. The fifth D is for "destination," a reminder to always consider the goal of the intervention...and whether that is in line with the patient's goals.
This is a framework, a place to begin. This post does not cover the literature or make recommendations for each section. I would encourage you to search PubMed, and peruse Palliative Care Fast Facts #10: Tube Feed or Not Tube Feed?, #84: Swallow Studies, Tube Feeding, and the Death Spiral, and #128: The Speech Pathologist and Swallowing Studies. Morrison and Goldstein also break down the evidence for artificial nutrition in various conditions in their textbook Evidence-Based Practice of Palliative Medicine.
The Five "Ds" of Artificial Nutrition
DESIRE: They don’t feel like eating
Examples: Cancer anorexia-cachexia, Depression, Frailty/Aesthenia “the dwindles”
DEMENTIA: They forgot how to eat
Examples: end-stage Alzeimer’s
DANGER: There is risk of aspiration and we won’t let them eat
Examples: Acute Stroke, ALS, critical illness
DAM(AGE): There is obstruction (Dam) or Damage of the GI tract
Examples: Mucositis, bowel obstruction, head and neck cancer, IBD
DESTINATION: What are the goals of therapy?
Will artificial nutrition bridge the patient through a reversible event? Will it prolong survival? Will it improve functional status? Will it maintain functional status? Has the patient expressed wishes regarding artificial nutrition? Have the goals of therapy been discussed with the patient and/or surrogate decision-maker?