Nutrition Assessment

Question 1

Copper deficiency is associated with

1: leukocytosis.
2: macrocytic anemia.
3: microcytic hypochromic anemia.
4: erythrocytosis.

Answer 1

• Patients on long-term parenteral nutrition have developed anemia, leukopenia, neutropenia and skeletal abnormalities.
• Deficiencies of B12 or folate result in macrocytic anemia (large red blood cells).
• Deficiencies of iron or copper result in microcytic hypochromic anemia (small red blood cells that are pale in color due to decreased heme pigment).
• Copper is a metallocofactor for enzymes involved in iron absorption and transport, electron transport, connective tissue cross-linking, and is a component of ceruloplasmin.

Question 2

A patient receiving PN with a high ileostomy output is likely to require

1: increased sodium and increased fluid volume.
2: decreased water and decreased sodium.
3: increased sodium and decreased protein.
4: decreased sodium and increased fluid volume.

Answer 2

Patients with ileostomy or small bowel fistula output are at risk for water and electrolyte losses. The sodium content of ileostomy output can be as high as 120 meq/liter. Hyponatremia can result when fluid replacement does not contain adequate sodium to correct for ileostomy losses.

Question 3

Which of the following is a characteristic of kwashiorkor malnutrition?

1: Splenomegaly
2: Hypoalbuminemia
3: Hypoglycemia
4: Cachexia

Answer 3

Kwashiorkor malnutrition is caused by insufficient protein intake during a prolonged period. The clinical features include hypoalbuminemia, edema, ascites, dermatitis, thin brittle hair, hepatomegaly and muscle wasting. In comparison, marasmus is caused by insufficient energy intake, and is characterized by extreme weight loss and cachexia.

Question 4

Which of the following conditions is most likely to result in malnutrition?

1: Cancer
2: Pneumonia
3: Gastric ulcer
4: Multiple sclerosis

Answer 4

In a study of nonsurgical patients examined for nutritional status, patients with cancer had a higher incidence of malnutrition as well as increased risk of developing complications during their hospital stay. This is probably the result of cancer cachexia, a wasting disease characterized by increased metabolism.

Question 5

Question: 5

Which of the following is the best indicator of risk for malnutrition?

1: Serial tricep skinfold remaining at the 20th percentile
2: Voluntary body mass index change from 30 to 25 over 6 months
3: Involuntary weight loss of 10% usual body weight over six months
4: Albumin decrease from 4.0 to 3.5

Answer 5

• Tricep skinfold thickness below the 5th percentile is abnormal in hospitalized patients.
• Tricep skinfold may be falsely elevated with edema, and may not be reliable in obese patients.
• Recent involuntary weight loss of 10% of usual body weight over 6 months detects obese and non-obese patients at risk for malnutrition.
• Voluntary weight loss from a BMI of 30 (obese) to a BMI of 25 (normal) does not reflect malnutrition. Albumin may be altered by conditions not related to nutritional factors.

Question 6

Question: 6

Which of the following is the most appropriate indicator of malnutrition?

1: Involuntary weight loss of 5% of usual body weight over three months
2: Involuntary weight loss of 10% of usual body weight over six months
3: Weight less than 10% of ideal body weight
4: Weight less than 15% of ideal body weight

Answer 6

Involuntary weight loss of greater than or equal to 5% of usual body weight in one month or 10% in 6 months are indicative of malnutrition. Body weight below ideal does not necessarily indicate malnutrition. Weight loss of 20% of ideal body weight, especially with increased nutritional requirements or if the loss is associated with chronic disease is an indicator of malnutrition.

Question 7

Which of the following is most characteristic of metabolism in both stress- and starvation-related malnutrition?

1: Ketosis
2: Hypoglycemia
3: Lipolysis
4: Hypermetabolism

Answer 7

Catabolism of endogenous substrate including fat stored in adipose tissue (lipolysis) is common in both forms of malnutrition. Hypoglycemia and ketosis are characteristic of starvation. Hypermetabolism and hyperglycemia are characteristic of stress-related malnutrition.

Question 8

Question: 8

Which of the following methods of nutrition assessment evaluate subcutaneous fat and muscle wasting at multiple body sites to determine nutritional status?

1: Nutritional risk index (NRI)
2: Prognostic nutrition index (PNI)
3: Subjective Global Assessment (SGA)
4: Prognostic inflammatory and nutritional index (PINI)

Answer 8

The SGA evaluates nutritional status using five historical and four physical examination parameters. The historical information includes: weight history, dietary intake, gastrointestinal symptoms, functional status, and metabolic demand.
The physical examination parameters include subjective measures of subcutaneous fat, muscle wasting, edema, and ascites at more than one body site.
The historical and physical examination data are subjectively weighted to classify the patient as well nourished, moderately malnourished, or severely malnourished.
The SGA has been found to be a good predictor of complications in patients undergoing gastrointestinal surgery, liver transplantation, and dialysis. The PNI, NRI, and PINI are prognostic indices that include objective measures of nutrition status. The formula for PNI includes a triceps skin fold thickness measurement, and serum albumin and transferrin levels, and delayed hypersensitivity skin test reactivity. The formula for PINI includes markers of the inflammatory response (alpha 1 acid glycoprotein and C-reactive protein) in addition to albumin and prealbumin. The formula for NRI uses serum albumin and the ratio of current weight to usual weight.

Question 9

The Subjective Global Assessment used to evaluate the nutritional status of patients includes

1: dietary intake, delayed hypersensitivity skin testing, and weight history.
2: weight history, dietary intake, and gastrointestinal symptoms.
3: laboratory indices, weight history, and gastrointestinal symptoms.
4: arm anthropometry, dietary intake, and laboratory indices.

Answer 9

The Subjective Global Assessment has been applied successfully as a method of assessing nutritional status in a variety of patient populations. It integrates five historical (weight history, dietary intake, gastrointestinal symptoms, functional status, metabolic demand) and four physical examination parameters (subcutaneous fat, muscle wasting, edema, ascites) to define nutritional status.

Question 10

Which of the following has been reported to be a significant independent predictor of morbidity and mortality in critically ill patients?

1: Albumin
2: Prealbumin
3: Transferrin
4: Retinol-binding protein

Answer 10

In a study including 1023 critically ill patients, albumin was a significant independent predictor of morbidity and mortality. ICU and hospital length of stay, ventilator days, risk of infection and mortality were significantly greater for patients with a serum albumin

Question 11

Which of the following compromises the reliability of urinary urea nitrogen to calculate nitrogen balance?

1: protein intake 2.5 L
4: fecal nitrogen >1g

Answer 11

Urine urea nitrogen is used primarily to monitor protein intake during nutrition support. Urine is usually collected for a 24-hour period in order to quantify the amount of urinary urea nitrogen. Compromised renal function, as indicated by a creatinine clearance <50 mL/min, low urine output, and muscle atrophy can alter urinary urea nitrogen, resulting in unreliable results.

Question 12

Question: 13

Which of the following has been shown to reduce plasma homocysteine concentrations?

1: Folic acid
2: Vitamin E
3: L-carnitine
4: Ascorbic acid

Answer 12

Hyperhomocysteinemia has been linked to an increased risk for coronary artherosclerosis. Studies have shown that folic acid, vitamin B6, and vitamin B12 supplementation can reduce plasma homocysteine concentrations. It is not known whether hyperhomocysteinemia is a causative factor of artherosclerosis or simply a marker of vascular disease.

References:

Homocysteine Lowering Trialist’s Collaboration. Dose-dependent effects of folic acid on blood concentration of homocysteine: a meta-analysis of the randomized trials. Am J Clin Nutr. 2005;82:806-812.

Question 13

Question: 14

Which of the following is the most appropriate fluid requirement for a healthy adult?

1: 15-20 ml fluid/kg/day
2: 20-25 ml fluid/kg/day
3: 30-35 ml fluid/kg/day
4: 40-45 ml fluid/kg/day

Answer 13

The fluid requirements for healthy adults are 30-40 ml/kg/day. 30-35 ml fluid/kg/day is the most appropriate choice.

References:

A.S.P.E.N. Board of Directors and the Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26(1 suppl):1SA-138SA.

Question 14

Question: 15

Which of the following enzymes initiates the digestive process of carbohydrates in the mouth?

1: Lipase
2: Lactase
3: Maltase
4: Amylase

Answer 14

The salivary gland releases an enzyme called alpha amylase that initiates hydrolysis of carbohydrate when food enters the mouth.
The degree of hydrolysis depends on the time that food is chewed and the nature of the food that enters the stomach.
Lipase is an enzyme released from the pancreas that is important in the digestion of fat.
Both lactase and maltase are located in the brush border cells of the small intestine and are important in intraluminal carbohydrate digestion.

Question 15

Question: 16

Iron is primarily absorbed in the

1: distal ileum.
2: distal jejunum.
3: proximal ileum.
4: proximal jejunum.

Answer 15

Iron is absorbed primarily in the proximal jejunum in the ferrous state rather than the ferric state. The ferric form of iron is insoluble in aqueous solutions and, therefore, not absorbed. Gastric acid is very important in maintaining dietary iron in the ferrous state.

References:

Sharma N, Butterworth J, Cooper BT. The emerging role of the liver in iron metabolism. Am J Gastroenterol. 2005;100:201-206.

Question 16

Question: 17

Which of the following amino acids is most crucial in small intestinal structure and function?

1: Alanine
2: Leucine
3: Aspartate
4: Glutamine

Answer 16

While all amino acids are important in metabolism, glutamine is a key fuel for the small intestine. Glutamine is essential for small intestinal structure and function. It could be useful to supplement glutamine to patients who are suffering trauma or receiving parenteral nutrition.

References:

Colaizzo-Anas T. Nutrient Intake, Digestion, Absorption, and Excretion. In: Gottschlich MM, ed. The A.S.P.E.N. Nutrition Support Core Curriculum: A Case-Based Approach-The Adult Patient. Silver Spring, MD: A.S.P.E.N.; 2007:3-18.

Question 17

Question: 18

In persons with phenylketonuria, tyrosine becomes an essential amino acid due to

1: an increase in the tyrosine hydroxylase enzyme.
2: a deficiency in the phenylalanine hydroxylase enzyme.
3: an increase in the phenylalanine hydroxylase enzyme.
4: a decrease in the tyrosine hydroxylase enzyme.

Answer 17

Phenylalanine hydroxylase is the enzyme involved in the conversion of phenylalanine to tyrosine. If there is a defect in this enzyme, a deficiency of tyrosine occurs. This is the reason tyrosine is included in phenylketonuria (PKU) formulas.

References:

Rutherford P, Poustie VJ. Protein substitute for children and adults with phenylketonuria. Cochrane Database of Systematic Reviews. 2005. Issue 4. Art.No.: CD004731. DOI: 10.1002/14651858.CD004731.pub2.

Question 18

Question: 19

Which of the following is an aromatic amino acid?

1: Valine
2: Leucine
3: Tyrosine
4: Isoleucine

Answer 18

Valine, leucine, and isoleucine are branched-chain amino acids. The aromatic amino acids include phenylalanine, tyrosine, tryptophan, and methionine. Altered amino acid metabolism is a hallmark of liver disease characterized by low levels of circulating branched-chain amino acids and elevated levels of circulating aromatic amino acids.

References:

Delich PC, Siepler JC, Parker P. Liver Disease. In: Gottschlich MM, ed. The A.S.P.E.N. Nutrition Support Core Curriculum: A Case-Based Approach-The Adult Patient. Silver Spring, MD: A.S.P.E.N.; 2007:540-557

Question 19

Question: 20

Which of the following are examples of conditionally indispensable amino acids?

1: Leucine and Isoleucine
2: Phenylalanine and Valine
3: Glutamine and Arginine
4: Histidine and Tryptophan

Answer 19

Conditionally indispensable amino acids are synthesized from other amino acids under normal conditions but require a dietary source in order to meet increased needs caused by metabolic stress. For example, Arginine becomes conditionally indispensable for wound healing. Conditionally indispensable amino acids include: Arginine, Cysteine, Glutamine, Glycine, Proline and Tyrosine.

Question 20

Question: 21

An NPO post-operative patient has been on 2-in-1 parenteral nutrition (PN) for three weeks. He develops a diffuse scaly dermatitis, hair loss, anemia and thrombocytopenia. Which of the following is the probable cause?

1: He has not been receiving IV fat emulsion (IVFE) for three weeks.
2: He has been receiving trace elements 3 times per week due to a national shortage.
3: He is receiving 20 kcal/kg per day from PN because of hyperglycemia.
4: He has PN related cholestasis and is experiencing fat malabsorption.

Answer 20

Provision of fat free PN for three weeks has resulted in essential fatty acid deficiency. Signs of essential fatty acid deficiency include scaly dermatitis, alopecia, thrombocytopenia, anemia and impaired wound healing. Provision of 2-4% of total calories as fat should be sufficient to prevent essential fatty acid deficiency.

Question 21

Question: 22

Which of the following IV fluids most closely resemble jejunal and ileal electrolyte content?

1: Lactated Ringer
2: 0.9% Sodium chloride (normal saline)
3: 0.45% Sodium chloride (1/2 normal saline)
4: D5 0.45% Sodium chloride

Answer 21

The electrolyte content of gastrointestinal secretions changes according to their location along the GI tract. The composition of jejunal and ileal fluids is listed below. Jejunum: Na = 95-120 mEq/L; K = 5-15 mEq/L; Cl = 80-130 mEq/L; Bicarbonate = 10-20 mEq/L. Ileum: Na = 110-130 mEq/L; K = 10-20 mEq/L; Cl = 90-110 mEq/L; Bicarbonate = 20-30 mEq/L. Lactated Ringer most closely resembles these values. IV electrolyte content is as follows: Lactated Ringer: Glucose = 0; Na = 130 mEq/L; Cl = 109 mEq/L; K = 4 mEq/L; Lactate = 28 mEq/L; Ca = 2.7 mEq/L. 0.9% NaCl(NS) contains only: Na - 154 mEq/L and Cl 154 mEq/L. 0.45% NaCl (1/2 NS) contains only: Na = 77 mEq/L and Cl = 77 mEq/L. D5 0.45% NaCl contains: Glucose = 50 grams/L; Na = 77 mEq/L; Cl = 77 mEq/L.

Question 22

Which of the following clinical situations would best describe a critically ill patient with syndrome of inappropriate antidiuretic hormone (SIADH)?

1: Appears euvolemic but is total body water overloaded because there is inappropriate concentration of the urine
2: Appears hypervolemic and is total body water overloaded because there is inappropriate dilution of the urine
3: Appears hypovolemic but is total body water overloaded because there is inappropriate fluid resorption in the kidneys
4: Appears euvolemic but is total body water overloaded because there is inadequate production and release of anti-diruetic hormone from the adrenal glands

Answer 22

Hyponatremia associated with SIADH is common in the critically ill patient. It is seen frequently in patients with central nervous system disease, malignancy, lung disease and can also be a side effect of medications such as diuretics, antidepressants, and analgesics. The role of antidiuretic hormone is to control water loss via the kidneys depending on individual hydration status. When excessive antidiuretic hormone is produced, water is conserved rather than excreted and the urine becomes concentrated. Spot urine sodium levels and urine osmolality will both be elevated. The clinical picture associated with SIADH is euvolemia with total body water overload due to an inappropriate concentration of the urine.

Question 23

Topic B. Nutrient Requirements Question: 24

In a patient with nonhealing wounds suspected of having a vitamin A deficiency, supplementation of vitamin A (25,000 IU/day) should usually be given for a MAXIMUM of

1: 2 days.
2: 10 days.
3: 45 days.
4: 60 days.

Answer 23

Vitamin A has multiple functions in wound healing including cellular differentiation, enhancement of epithelialization and collagen synthesis. However, it can be toxic at high doses and, therefore, supplementation should be limited to no more than 10 days. Vitamin A supplementation may be contraindicated in patients with renal or liver failure and should be used cautiously in the older adult.

References:

Stechmiller JK, Cowan L, Johns P. Wound Healing. In: Gottschlich MM, ed. The A.S.P.E.N. Nutrition Support Core Curriculum: A Case-Based Approach-The Adult Patient. Silver Spring, MD: A.S.P.E.N.; 2007:405-423..

Question 24

Question: 25

A patient with alcoholism is admitted with small bowel obstruction and is started on PN providing 400 grams of dextrose. If, after 3 days, the patient develops Wernicke’s encephalopathy it is most likely due to a deficiency of

1: pyridoxine.
2: thiamine.
3: folic acid.
4: vitamin C.

Answer 24

Alcohol-related thiamine deficiency often presents as Wernicke’s encephalopathy. Alcoholic or malnourished patients may require thiamine supplementation. Thiamine plays an essential role in glucose metabolism. The glucose loads associated with parenteral nutrition increases the metabolic demand for thiamine.

References:

DiCecco SR, Francisco-Ziller N. Nutrition in Alchoholic Liver Disease. NCP. 2006;21:245-254.

Question 25

Question: 26

Lactic acidosis can be a result of which vitamin deficiency?

1: Folic acid
2: Vitamin E
3: Thiamine
4: Vitamin C

Answer 25

Thiamine is necessary for the metabolism of glucose, specifically, the conversion of pyruvate to acetyl CoA. In the absence of thiamine, pyruvate is converted to lactic acid. This, sometimes fatal, adverse event has occurred within a week of thiamine abstinence. The relatively high glucose loads of parenteral nutrition exacerbate the risk. Despite adequate supplies of adult parenteral multivitamin preparations since 1999, suboptimal dosing practices have persisted.

Question 26

Question: 27

In addition to aggressive refeeding, which of the following places a patient at high risk for hypophosphatemia?

1: Diabetic ketoacidosis, chronic alcoholism
2: Parkinson disease, tumor lysis syndrome
3: Pancreatitis, Fanconi syndrome
4: Acute renal failure, SIADH

Answer 26

Patients particularly at risk for hypophosphatemia include malnourished patients who are aggressively renourished, patients with diabetic ketoacidosis, and chronic alcoholism. Aggressive refeeding increases insulin production. Insulin is an anabolic hormone which drives potassium and phosphorus into the cell resulting in serum depletion. In diabetic ketoacidosis, substantial urinary losses of phosphate occur secondary to the osmotic diuresis associated with hyperglycemia. However, studies have not been able to show that phosphorus replacement therapy improves outcome. Hypophosphatemia associated with chronic alcoholism is caused by dietary deficiency, malabsorption and increased cellular intake. Acute renal insufficiency causes hyperphosphatemia due to decreased excretion. Fanconi syndrome can be associated with hypophosphatemia. Tumor lysis syndrome causes hyperphosphatemia.

Question 27

Question: 28

The risk of metastatic calcification of calcium phosphate in soft tissues increases when the product of phosphorus and calcium in the serum (serum phosphorus x serum total calcium) exceeds

1: 25.
2: 35.
3: 45.
4: 55.

Answer 27

A primary complication of hyperphosphatemia, besides hypocalcemia, is metastatic calcification in soft tissues, blood vessels, and organ parenchyma. The risk of metastatic calcification of calcium phosphate in soft tissues increases when the product of phosphorus and calcium in the serum (serum phosphorus x serum total calcium) is as low as 55.

References:

DiBenedetto BP, Goode JL. Nutrition Assessment in Chronic Kidney Disease. A Clinical Guide to Nutrition Care in Renal Disease. Byham-Gray L, Wiesen K, eds. Chicago: ADA; 2004:7-20.

Question 28

Question: 29

Zinc deficiency caused by malnutrition is most likely to result in

1: diarrhea.
2: carotenemia.
3: coagulopathy disorder.
4: increased absorption of nutrients.

Answer 28

Zinc helps regenerate gut epithelium and increase levels of brush border enzymes. Protein energy malnutrition compromises zinc status by activating cyclic guanine monophosphate (cGMP) synthesis which inhibits sodium and chloride absorption and stimulates chloride secretion, causing diarrhea. Zinc losses are increased due to the diarrhea, further exacerbating absorption of nutrients in the gut.

Wapnir RA. Zinc deficiency, malnutrition and the gastrointestinal tract. Journal of Nutrition. 2000;130:1388S-1392S.
Granger DA, Kivlighan KT, el-Sheikh M. Salivary alpha-amylase in biobehavioral research: recent developments and applications. Ann NY Acad Sci. 2007;1098:122-144.

Question 29

Question: 30

Copper toxicity is associated with

1: liver disease.
2: kidney disease requiring hemodialysis.
3: aggressive zinc supplementation.
4: lung disease.

Answer 29

Copper toxicity can cause severe nausea, diarrhea, and vomiting. More serious manifestations with acute or more chronic toxic ingestion or Wilson’s disease include coma, hepatic necrosis, liver failure, renal failure, vascular collapse, and death. Since about 80% of copper is excreted in the bile, patients who have liver disease should be monitored and supplementation reduced or eliminated. Hemodialysis increases copper losses. Zinc supplementation can impair copper absorption.

Question 30

Question: 31

Hepatic encephalopathy is most likely to be improved by which of the following trace elements?

1: Selenium
2: Copper
3: Zinc
4: Chromium

Answer 30

Zinc deficiency is very common in liver disease. Data suggest that supplementation with oral zinc is associated with improvement in amino acid metabolism and encephalopathy.

References:

Hanje AJ, Fortune B, Song M, Hill D, McClain, C. The Use of Selected Nutrition Supplements and Complementary and Alternative Medicine in Liver Disease. NCP. 2006;21:255-272.

Question 31

Question: 32

Which of the following best describes the utility of aluminum in parenteral solutions?

1: Potentiates the action of insulin
2: Has no known biologic function
3: Decreases the incidence of bone fractures
4: Is necessary for normal erythropoiesis

Answer 31

Aluminum has not been shown to have any biologic function but is present as a contaminant in many PN components. Toxicity occurs upon accumulation and can result in abnormalities of hematopoietic, bone, and neurologic functions. Complications of aluminum intake are best avoided by minimizing the use of aluminum-containing agents such as antacids, sucralfate, etc. Aluminum toxicity is treated with deferoxamine, an agent that chelates aluminum.

Task Force for the Revision of Safe Practices for Parenteral Nutrition: Mirtallo J, Canada T, Johnson D, et al. Safe practices for parenteral nutrition. JPEN. 2004;28(6 Suppl):S39-S70.

Question 32

Question: 33

Which of the following can result in an invalid indirect calorimetry measurement?

1: Enterocutaneous Fistula
2: Chest tube leak
3: Hemodynamic stability
4: Inspired oxygen (FiO2) less than 60%

Answer 32

Clinical factors can affect the validity of indirect calorimetry measurements in critical illness. For instance, if the patient requires inspired oxygen (FiO2) > 60%, the indirect calorimetry study should not be performed since the results may be inaccurate. The presence of an air leak can produce invalid results, as possible with a chest tube or bronchopleural fistula and within an endotracheal tube cuff. Furthermore, hemodialysis can alter measurements because of the potential loss of CO2 through the dialysis coil.

Haugen HA, Chan LN, Li F. Indirect calorimetry: a practical guide for clinicians. NCP. 2007;22(4):377-388.

Question 33

Question: 34

In assessing the caloric goal for patients receiving nutrition support, the measured resting energy expenditure determined from indirect calorimetry should be

1: reduced by 10% if respiratory quotient exceeds 1.0.
2: increased by a stress factor of 1.2-1.5 for sepsis or trauma.
3: adjusted by a thermogenesis factor for enterally fed patients.
4: used as the caloric target without addition of stress or activity factors.

Answer 33

Resting energy expenditure (REE) measured under steady state conditions closely approximates true 24-hour energy expenditure. The addition of a stress or activity factor may not be necessary and could result in overfeeding. If a patient is measured while fasting or if feedings are intermittently provided, it is reasonable to allow an additional 5% factor to account for thermogenesis.

References:

Wooley JA, Sax HC. Indirect calorimetry: Applications to practice. NCP. 2003;18:434-439.

Question 34

Question: 35

A respiratory quotient (RQ) of .95 most likely suggests

1: primarily fat oxidation.
2: mixed substrate utilization.
3: underfeeding.
4: overfeeding.

Answer 34

RQ = CO2 produced/O2 consumed. An RQ 1.0 may result from unusual metabolic factors (hypoventilation or hyperventilation). Overfeeding or underfeeding may result in an RQ outside the 0.7-1.0 range, however this is not always the case. Traditional interpretation of RQ is as follows: RQ of 0.7 is primarily fat oxidation, 0.82 is primarily protein oxidation, 0.85-0.95 suggests mixed substrate utilization, and 1.0 is carbohydrate oxidation.

ADA Evidence Analysis Library. Using RQ to detect energy expenditure measurement error in healthy, obese and critically ill adults. http://ada.portalxm.com/eal/evidence.cfm?evidence_summary_id=79&highlight=RQ&home=1. Accessed 9/13/07.

Question 35

Question: 36

Which of the following predictive equations has demonstrated the greatest accuracy in estimating actual resting metabolic rate in obese and nonobese adults?

1: Owen using adjusted body weight
2: Harris-Benedict using actual body weight
3: Harris-Benedict using adjusted body weight
4: Mifflin-St. Jeor using actual body weight

Answer 35

The Mifflin-St. Jeor equations have demonstrated the greatest accuracy with obese and non-obese people when compared to the Owen equations and Harris-Benedict equations using either adjusted or actual body weight. The Mifflin-St. Jeor equations are as follows: For males: Actual body weight in kg x 9.99 plus Height in cm x 6.25 minus age in years x 4.92 plus 5. For females: Actual body weight in kg x 9.99 plus Height in cm x 6.25 minus age in years x 4.92 minus 161.

Frankenfield DC, Rowe WA, Smith JS, et al. Validation of several established equations for resting metabolic rate in obese and non-obese people. Journal of the American Dietetic Association. 2003;103:1152-1159.

Question 36

Question: 37

Cheilosis is a physical symptom associated with a deficiency of

1: vitamin D.
2: folic acid.
3: riboflavin.
4: vitamin C.

Answer 36

Cheilosis, cracking of the corners of the mouth, is observed with a deficiency of riboflavin, niacin, iron, and pyridoxine.

References:

Hammond KA. History and physical examination. In: Matarese LE, Gottschich MM. Contemporary Nutrition Support Practice: A Clinical Guide. 2nd Edition. Philadelphia: Saunders;2003:14-30.

Question 37

Question: 38

Malnutrition is most common in which of the following forms of inflammatory bowel disease?

1: Crohn’s disease
2: Ulcerative colitis
3: Microscopic colitis
4: Collagenous colitis

Answer 37

Since Crohn’s disease usually involves the small intestine, malnutrition and micronutrient deficiencies are much more common than with ulcerative, microscopic, or collagenous colitis. Depending on severity of disease, weight loss has been reported in 65% to 78% of those with Crohn’s disease. Possible mechanisms for malnutrition in Crohn’s disease include malabsorption from diseased small bowel mucosa, increased nutrient requirements from active inflammation, and reduced oral food intake due to abdominal discomfort and diarrhea.
A.S.P.E.N. Board of Directors and the Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26(1 suppl):1SA-138SA.

Question 38

Question: 39

An end stage liver disease patient with refractory ascites is awaiting liver transplantation and is intolerant to tube feeding. His serum sodium is 128 mEq/L. Which of the following would be most appropriate to recommend?

1: No parenteral nutrition
2: Restrict fluid, restrict sodium , provide 0.5 g/kg per day protein
3: restrict fluid, restrict sodium, provide 1.5 g/kg per day protein
4: Restrict fluid, supplement sodium, provide 1.0 g/kg per day protein

Answer 38

Appropriate treatment for ascites includes fluid and sodium restriction. Current literature supports the use of protein 0.8 to 1.2 g/kg/day for maintenance and 1.3 to 2.0 g/kg/day for repletion. While optimum nutrition support may not be possible, use of maximally concentrated solutions provides the best opportunity to avoid further salt and fluid overload while providing necessary substrate for anabolism.

Raup SM, Kaproth P. Hepatic Failure. In:Matarese LE, Gottschlich MM, eds. Contemporary Nutrition Support Practice: A Clinical Guide. 2nd ed. Philadelphia: Saunders; 2005:445-459.

Question 39

Question: 40

Arginine supplementation should be used most cautiously in which of the following patients?

1: Trauma patients
2: Surgical patients
3: Septic shock patients
4: Immunocompromised patients

Answer 39

Arginine, which increases the production of nitric oxide, has been shown to have positive effects on recovery from trauma and surgery through its effect on blood flow, immune function, wound healing, and organ failure. In conditions of pronounced vasodilation, as in septic shock, the production of nitric oxide would be expected to exacerbate hemodynamic instability. Increased mortality and morbidity in this population has been demonstrated in some studies.

Zhou M, Martindale R. Arginine in the Critical Care Setting. 6th Amino Acid Assessment Workshop. J Nutrition. 2007;(S):1687S-1692S.

Question 40

Question: 41

What is the approximate normal length of small intestine in adults?

1: 100 cm
2: 150 cm
3: 200 cm
4: 600 cm

Answer 40

The normal small intestine is approximately 600 cm in length. The colon is approximately 150 cm. Patients with less than 150-200 cm of small bowel without a colon may have significant fluid and nutrient losses, i.e. short bowel syndrome.

References:

Scolapio JS. Short bowel syndrome. JPEN. 2002;26(5 Suppl):S11-S16.

Question 41

Question: 42

What is the primary fuel of the colonocytes?

1: Medium chain fatty acids
2: Glucose
3: Glutamine
4: Short chain fatty acids

Answer 41

Short chain fatty acids are the primary fuel product for colonic cells. The short chain fatty acids include acetate, propionate, and butyrate. The colon can convert (by fermentation) complex carbohydrate to short chain fatty acids. The short chain fatty acids stimulate water and sodium absorption in the colon and provide a source of calories as well.

References:

Scolapio JS. Short bowel syndrome. JPEN. 2002;26(5 Suppl):S11-S16.

Question 42

Question: 43

Dietary fat is predominately absorbed in what part of the intestine?

1: Ileum and colon
2: Stomach and duodenum
3: Distal jejunum and ileum
4: Duodenum and proximal jejunum

Answer 42

4. Absorption of fat in the normal person occurs predominantly in the duodenum and proximal jejunum. Conjugated bile acids released into the proximal intestine forms polymolecular aggregates called mixed micelles, which aid in the solubilization and absorption of dietary fat.

References:

Jeejeebhoy KU. Short Bowel Syndrome: a Nutritional and Medical Approach. CMAJ. 2002;166:1297-1302.
A gastrectomy is the total or partial removal of the stomach. Parietal cells in the stomach are responsible for producing intrinsic factor, which under normal circumstances binds with Vitamin B12 and aids in the absorption of B12 in the small bowel. When the stomach is resected, there is no longer adequate intrinsic factor to bind with B12, and thus a deficiency may result.

Question 43

Question: 44

Gastrectomy patients are at risk for a deficiency of which vitamin?

1: B12
2: Folic Acid
3: Thiamine
4: B6

Answer 43

A gastrectomy is the total or partial removal of the stomach. Parietal cells in the stomach are responsible for producing intrinsic factor, which under normal circumstances binds with Vitamin B12 and aids in the absorption of B12 in the small bowel. When the stomach is resected, there is no longer adequate intrinsic factor to bind with B12, and thus a deficiency may result.

Question 44

Question: 45

Which of the following anatomic structures is LEAST important to the function of a massively resected gastrointestinal tract?

1: Colon
2: Ileum
3: Jejunum
4: Ileocecal valve

Answer 44

The ileum has specific absorption functions that cannot be performed in any other area of the GI tract. The ileocecal valve and colon play an important role in transit time and electrolyte balance. The jejunum cannot adapt to perform the functions of a resected ileum or colon, whereas the illeum or colon can assume function of a resected jejunum over time.

Wall-Alonso E, Sullivan MM, Byrne TA. Gastrointestinal and pancreatic disease. In: Matarese LE, Gottschlich MM, eds. Contemporary Nutrition Support Practice A Clinical Guide. 2nd ed. Philadelphia: Saunders; 2005:412-444.

Question 45

Question: 46

Which of the following is associated with adaptation to starvation?

1: Hyperthermia
2: Reduced muscle mass
3: Lipogenesis
4: Increased cardiac capacity

Answer 45

During starvation, successful adaptation reduces energy and protein requirements as long as the ratio of energy to protein is not too low. The physiologic costs of adaptation are lowered metabolic rate, reduced muscle mass, muscular weakness, functional disability, mild hypothermia, and reduced cardiac and respiratory capacity. Adaptation to starvation helps restore homeostasis and helps the body maintain key physiologic functions.

References:

Hoffer LJ. Clinical nutrition: 1. Protein-energy malnutrition in the inpatient. Canadian Medical Association Journal. 2001;165:1345-1349.

Question 46

Question: 47

What is the fluid requirement for patients during critical illness and sepsis?

1: 15-25 mL/kg/day
2: 30-40 mL/kg/day
3: 45-55 mL/kg/day
4: 60-70 mL/kg/day

Answer 46

Water is imperative for digestion, transport, and metabolism of nutrients as well as elimination of waste. Fluid volume of 30-40 mL/kg/day is needed to meet the fluid demand seen in critical illness, as well as to maintain adequate urine output.

References:

A.S.P.E.N. Board of Directors and the Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26(1 suppl):1SA-138SA.

Question 47

Question: 48

Valproic acid (Depakene) has been shown to induce a deficiency in which of the following nutrients?

1: Copper
2: Carnitine
3: Fatty acids
4: Essential amino acids

Answer 47

Valproic acid (Depakene), an antiepileptic drug, has been shown to induce carnitine deficiency. The mechanism of this effect is not fully explained. Impaired renal handling may be involved. Carnitine is involved in the metabolism of fatty acids. The idiopathic encephalopathy associated with carnitine deficiency is reversed with L-carnitine supplementation and restoration of carnitine serum levels. Fatalities have been reported in untreated carnitine deficiency.

Chan L. Drug-nutrient interactions in transplant recipients. JPEN. 2001;25:132-141.

Question 48

Question: 49

Methotrexate acts by interfering with the normal intracellular metabolism of which of the following nutrients?

1: Thiamine
2: Folate
3: Carnitine
4: Vitamin D

Answer 48

The chemotherapeutic drug methotrexate is an antifolate compound that first entered clinical trials in the 1950s and is one of the best-studied agents targeting the folate pathway. Folate analogues, such as methotrexate, are structurally similar to folate but are able to bind with and inhibit the action of various enzymes. Methotrexate acts primarily as an inhibitor of dihydrofolate reductase, resulting in an accumulation of dihydrofolate and a depletion of other folate pools.

Calvert H. Folate status and the safety profile of antifolates. Seminars in Oncology. 2002;29(supp 5):S3-S7.

Question 49

Topic D. Drug-Nutrient Interactions Question: 50

What vitamin absorption is most likely to be impaired with the use of proton pump inhibitor therapy?

1: Vitamin A
2: Vitamin C
3: Vitamin B6
4: Vitamin B12

Answer 49

Protein-bound dietary vitamin B12 requires gastric acidity for optimal release of free vitamin B12 from food; it is this free vitamin B12 that binds to R protein in the stomach and eventually to intrinsic factor in the small intestine for absorption. Proton pump inhibitors decrease gastric acidity and may thus interfere with the absorption of protein-bound dietary vitamin B12. Absorption of crystalline vitamin B12, the form utilized in vitamin supplements and fortified foods, is not affected by gastric acid.

Ruscin JM, Page RL2nd, Valuck RJ. Vitamin B₁₂ deficiency associated with histamine(2)-receptor antagonists and a proton-pump inhibitor. Annals of Pharmacotherapy. 2002;36:812-816.