II. Nutrition Assessment
There are numerous risk factors for poor nutritional status, including major trauma, burns, sepsis, substance abuse,
recent weight loss, and many gastrointestinal disorders. Additional information learned through a careful medical history
can also suggest possible risk factors for malnutrition. The factors
listed below may place a patient at risk for developing, or may
denote the presence of, nutrient deficiencies.
- Age < 18 years or > 65 years (increased risk age >75 years)
- Recent significant, unintentional weight loss: > 5% in 1 month or >10% in 6 months
- Weight loss calculated as follows:
- Percent weight loss = (UBW-CBW)/UBW
- Where: UBW = usual body weight, CBW =current body weight
- Excessive alcohol intake, other substance abuse
- Homelessness, limited access to food
- Limited capacity for oral intake (dysphagia, odynophagia, stomatitis, mucositis)
- NPO > 3 days
- Increased metabolic demands: extensive burns, major surgery, trauma, fever, infection, draining, abscesses, wounds, fistulae, pregnancy
- Protracted nutrient losses: malabsorption syndromes, short gut syndrome, draining abscesses, wounds, fistulae, effusions, renal dialysis
- Intake of catabolic drugs: corticosteroids, immunosuppressants, antineoplastics
- Protracted emesis: anorexia nervosa, bulimia, hyperemesis gravidarum, radiation, cancer chemotherapy
- Chronic disease (especially AIDS, diabetes, cystic fibrosis, stroke, cancer)
A detailed diet history provides insight into a patient's
baseline nutritional status and may detect subclinical nutrient
deficiencies or toxicities. Assessment includes questions
regarding chewing or swallowing problems, avoidance of eating
related to abdominal pain, changes in appetite, taste, or intake, as
well as use of a special diet or nutritional supplements.
A review of past medical history includes identifying
existence of conditions resulting in increased metabolic needs,
altered gastrointestinal function and absorptive capacity,
chronic disease states, organ failure, and levels of physical activity.
A review of current medications may further elucidate
at-risk nutrient status. (See Appendix A).
Physical examination should focus on assessment of
muscle mass and strength, evidence for chronic liver disease and
signs of vitamin or mineral deficiency. In the United States it
is uncommon, though not rare, to find patients with
classical manifestations of far-advanced vitamin or mineral
deficiencies (see Appendix B), though short term, acute vitamin
deficiencies are more common than appreciated.
A systematic bedside assessment of nutritional status has
been shown to accurately categorize patients as well
nourished, moderately malnourished or severely malnourished.
A worksheet adapted from the original research
publication (JPEN 1987; 11:8-13) can be found in Appendix C.
Biochemical measurements are useful to assess organ
function, fluid status and electrolyte balance, confirm nutritional
deficiencies, and monitor the adequacy of nutritional therapies.
Useful baseline laboratory data includes basic chemistries (e.g.
electrolytes, glucose, BUN and creatinine), liver function tests,
hemogram, albumin, and transthyretin. C-Reactive protein should
be measured concomitantly with transthyretin in patients
with suspected metabolic response to injury/infection. For
further comments on the use of laboratory tests see Section:
VII. Monitoring Nutrition Therapy (page 37). Laboratory tests
for individual nutrients are available (see Appendix
D).
Table of Contents | III. Estimating Nutritional Requirements