Nutritional Assessment

Question 1

Copper deficiency is associated with
1: leukocytosis.
2: macrocytic anemia.
3: microcytic hypochromic anemia.
4: erythrocytosis.

Answer 1

3: microcytic hypochromic anemia.

Patients on long-term parenteral nutrition have developed anemia, leukopenia, neutropenia and skeletal abnormalities. Deficiencies of iron or copper result in microcytic hypochromic anemia (small red blood cells that are pale in color due to decreased heme pigment). Deficiencies of B12 or folate result in macrocytic anemia (large red blood cells). Other symptoms of copper deficiency include: sensory ataxia, lower extremity spasticity, parathesis in extremities, leukopenia, neutropenia, hypercholesterolemia, increased erythrocyte turnover, decreased ceruloplasmin and erythrocyte copper/zinc superoxide dismutase (SOD), abnormal EKG patterns, myeloneuropathy. Copper deficiency can be a complication of Celiac disease

Question 2

A patient receiving PN has a high ileostomy output. Which of the following changes to the PN prescriptions is most appropriate to recommend?
1: increase sodium and increase fluid volume.
2: decrease water and decrease sodium.
3: increase sodium and decrease protein.
4: decrease sodium and increase fluid volume.

Answer 2

1: increase sodium and increase fluid volume.

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 acute disease-associated malnutrition?
1: Splenomegaly
2: Anasarca – generalized swelling
3: Hypoglycemia
4: Anemia

Answer 3

2: Anasarca – generalized swelling

Acute disease-associated malnutrition is caused by an acute inflammatory response. The clinical features include hypoalbuminemia, edema, and anasarca.

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

1: Cancer

In a large multicenter cooperative study, over half of cancer patients present with weight loss at diagnosis (range 31-80%). Unintentional weight loss is a criterion for diagnosis of malnutrition. The amount and frequency of weight loss varied with type of cancer, location, grade, and stage. Type of anti-cancer treatments can also further impact nutritional status.

Question 5

Which of the following is most suggestive of malnutrition?
1: 10th percentile of tricep skinfold thickness
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

3: Involuntary weight loss of 10% usual body weight over six months

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

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

2: Involuntary weight loss of 10% of usual body weight over six months

Involuntary weight loss of greater than or equal to 5% of usual body weight in one month, 7.5% in 3 months 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 common in both stress- and starvation-related malnutrition?
1: Ketosis
2: Hypoglycemia
3: Lipolysis
4: Hypermetabolism

Answer 7

3: Lipolysis

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

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

3: Subjective Global Assessment (SGA)

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, 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

2: weight history, dietary intake, and gastrointestinal symptoms.

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

1: Albumin

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 <2.6 g/dL.

Question 11

A previously well-nourished patient with persistent fever is admitted to the hospital. His laboratory tests reveal: albumin, 2.1 g/dL; C-reactive protein, 30 mg/L; serum calcium of 7.2 mg/dL. Which of the following is the most likely etiology of hypoalbuminemia?

1: Caloric deficiency
2: Protein deficiency
3: Hypocalcemia
4: Inflammatory response

Answer 11

4: Inflammatory response

Albumin may decrease during inflammation and hypervolemia. Even though it is a good predictive indicator of clinical outcome, it does not always reflect nutritional status. Elevated C-reactive protein reflects an inflammatory status, which may be the reason for hypoalbuminemia. Positive acute phase protein concentrations such as C-reactive protein increase during inflammation, whereas negative acute phase protein concentrations such as albumin and pre-albumin decrease during inflammation. Although there is a causal relationship between hypoalbuminemia and hypocalcemia, a low serum calcium does not cause a low serum albumin.

Question 12

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

1: Protein intake <0.5 g/kg/day
2: Creatinine clearance <50 mL/min
3: Diuresis >2.5 L
4: Fecal nitrogen >1g

Answer 12

2: Creatinine clearance <50 mL/min

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 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 13

1: Folic acid

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

Question 14

Which of the following is the most appropriate fluid requirement for a healthy 78-year old adult?

1: 20 ml fluid/kg/day
2: 25 ml fluid/kg/day
3: 35 ml fluid/kg/day
4: 45 ml fluid/kg/day

Answer 14

2: 25 ml fluid/kg/day

The fluid requirements for healthy adults are:
35ml/kg for adults age 18-55,
30ml/kg for adults age 55-75
25ml/kg for adults older than 75 years, and less than 25ml/kg when fluid restriction is indicated.

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 15

4: Amylase

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 16

Iron is primarily absorbed in the
1: stomach.
2: colon.
3: ileum.
4: jejunum.

Answer 16

4: jejunum.

Iron is absorbed primarily in the duodenum and 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.

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 17

4: Glutamine

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.

Question 18

In persons with phenylketonuria(PKU), 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 18

2: a deficiency in the phenylalanine hydroxylase enzyme.

PKU is an inborn error of phenylalanine metabolism caused by a deficiency of the hepatic enzyme phenylalanine hydroxylase (PAH). PAH catalyzes the hydroxylation of phenylalanine to tyrosine. In the absence of PAH, phenylalanine levels become extremely high and tyrosine becomes deficient. Treatment with a phenylalanine-free diet and tyrosine supplementation is used for chronic management.

Question 19

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

3: Glutamine and Arginine

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

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

1: He has not been receiving IV fat emulsion (IVFE) for three weeks.

Provision of fat free PN for three weeks has resulted in essential fatty acid deficiency (EFAD). EFAD usually results after 4 week of fat free PN, although signs of deficiency can be seen as early as 10-20 days in adults although deficiency can occur more rapidly in infants and children. Signs of EFAD 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. Trace elements deficiencies need to be monitored in the light of shortages. Using ASPEN guidelines should reduce the risk. Hypocaloric PN actually may benefit patient on fat free PN as it is thought that EFA are released as a result of lipolysis of endogenous fat stores in response to reduction in insulin levels. Cholestasis is usually associated with high IVFE doses.

Question 21

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

1: Lactated Ringer’s
2: Normal saline
3: 1/2 normal saline
4: D5 0.45% Sodium chloride

Answer 21

1: Lactated Ringer’s

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: Sodium = 95-120 mEq/L; Potassium = 5-15 mEq/L; Chloride = 80-130 mEq/L; Bicarbonate = 10-20 mEq/L.
Ileum: Sodium = 110-130 mEq/L; Potassium = 10-20 mEq/L; Chloride = 90-110 mEq/L; Bicarbonate = 20-30 mEq/L.

Lactated Ringer’s most closely resembles these values. IV electrolyte content is as follows: Lactated Ringer’s: Glucose = 0; Sodium = 130 mEq/L; Chloride = 109 mEq/L; Potassium = 4 mEq/L; Lactate = 28 mEq/L; Calcium = 2.7 mEq/L

Question 22

All of the following are clinical symptoms of syndrome of inappropriate antidiuresis (SIAD) EXCEPT:

1: Hypervolemia
2: Increased urinary sodium
3: Hyponatremia
4: Increased urinary osmolality

Answer 22

SIAD is one of the most common causes of hyponatremia. It is a disorder of sodium and water balance caused by the inappropriate release of antidiuretic hormone (ADH). The result is an increased in total body water which causes a dilutional hyponatremia. Increased sodium concentrations and osmolality are seen in the urine due to excessive water reabsorption. To compensate for expansion of extracellular fluid, aldosterone secretion is inhibited while atrial natriuretic peptide (ANP) increases. These compensative responses serve to maintain euvolemia, but at the same time further worsen hyponatremia. Due to the fact that not all afflicted patients show elevated circulating levels of ADH, the expression “syndrome of inappropriate antiduresis” has been determined to be more accurate.

Question 23

In 45 year old a patient with normal liver and kidney function and 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: 3 days.
2: 14 days.
3: 90 days.
4: 180 days.

Answer 23

2: 14 days

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, the recommended course for supplementation is up to 14 days. Vitamin A supplementation may be contraindicated in patients with renal or liver failure and should be used cautiously in the older adult.

Question 24

An old 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 mental status changes it is most likely due to a deficiency of
1: pyridoxine.
2: thiamine.
3: folic acid.
4: vitamin C.

Answer 24

2: thiamine.

Alcohol-related thiamine deficiency often presents as Wernicke’s encephalopathy, which can present as mental status changes, confusion, nystagmus, gait ataxia, and polyneuritis. 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.

Question 25

Lactic acidosis can be a result of which vitamin deficiency?
1: Folic acid
2: Vitamin E
3: Thiamine
4: Vitamin C

Answer 25

3: Thiamine

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

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

1: Diabetic ketoacidosis(DKA)
2: Tumor lysis syndrome
3: Vitamin D deficiency
4: Acute kidney injury(AKI)

Answer 26

1: Diabetic ketoacidosis(DKA)

Patients at risk for hypophosphatemia include malnourished patients aggressively refed, patients with DKA, chronic alcoholism, respiratory and metabolic alkalosis, critical illness and Fanconi syndrome. Insulin is an anabolic hormone that drives potassium and phosphorus into cells and results in serum depletion. In DKA substantial phosphorous is lost in urine as a result of osmotic diuresis associated with hyperglycemia. Tumor lysis syndrome can result in high serum phosphorus levels. Vitamin D deficiency is associated with hypocalcemia, osteomalacia, osteoporosis. AKI can lead to high phosphorus levels as a result of decreased excretion

Question 27

The risk of metastatic calcification in soft tissues begins to increase when the product of calcium x phosphorous exceeds

1: 25.
2: 55.
3: 75.
4: 95.

Answer 27

2: 55.

A primary complication of hyperphosphatemia is soft tissue and vascular calcification. Calcification occurs when the product of calcium x phosphorus exceeds 55. Additional symptoms of hyperphosphatemia include secondary hyperparathyroidism and renal osteodystrophy. Hypocalcemia occurs with hyperphosphatemia and symptoms include anorexia, nausea, vomiting, dehydration and neuromuscular irritability

Question 28

Zinc deficiency is most commonly associated with
1: diarrhea.
2: carotenemia.
3: coagulopathy disorder.
4: cholestasis.

Answer 28

1: diarrhea.

Zinc helps regenerate gut epithelium and increase levels of brush border enzymes. Zinc losses are increased due to the diarrhea, further exacerbating absorption of nutrients in the gut.

Question 29

Copper toxicity is associated with

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

Answer 29

1: liver disease.

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. Enteral zinc supplementation can compete with copper for absorption.

Question 30

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

3: Zinc

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.

Question 31

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

2: Has no known biologic function

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.

Question 32

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

2: Chest tube leak

Technical factors can affect the validity of indirect calorimetry measurements in critical illness. Any air leaks such as leaking chest tubes, bronchopleural fistulas, or leaks in the sampling system will prevent collection of all expired gases, thereby invalidating results. High mechanical ventilation settings such as inspired oxygen (FiO2) > 60% or positive end expiratory pressure (PEEP) > 12 cm H2O can also yield erroneous results. Furthermore, hemodialysis can alter measurements because of the potential loss of CO2 through the dialysis coil.

Question 33

How should a critically ill patient’s energy delivery be modified in response to resting energy expenditure (REE) measured by indirect calorimetry?
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

4: used as the caloric target without addition of stress or activity factors.

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.

Question 34

A respiratory quotient (RQ) of 0.87 most likely suggests
1: primarily fat oxidation.
2: mixed substrate utilization.
3: primary carbohydrate oxidation.
4: primary protein oxidation.

Answer 34

2: mixed substrate utilization.

RQ = CO2 produced/O2 consumed. An RQ <0.7 or >1.0 may result from hypoventilation or hyperventilation. While there are several metabolic causes for an RQ < 0.7 or > 1.0, traditional interpretation of RQ is as follows: RQ of 0.71 is primarily fat oxidation, 0.82 is primarily protein oxidation, 0.85 suggests mixed substrate utilization, and 1.0 is carbohydrate oxidation.

Question 35

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

4: Mifflin-St. Jeor using actual body weight

The Mifflin-St. Jeor equations have demonstrated the greatest accuracy with healthy 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.

Question 36

Cheilosis is a physical symptom associated with a deficiency of
1: vitamin D.
2: folic acid.
3: riboflavin.
4: vitamin C.

Answer 36

: riboflavin

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

Question 37

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

1: Crohn’s disease

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 20% to 85% 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

Question 38

An end stage liver disease patient with refractory ascites is awaiting liver transplantation and is intolerant to tube feeding. His serum sodium is 124 mEq/L. Which of the following is most appropriate to recommend?

1: Restrict fluid, supplement sodium, provide 2.5g protein/kg per day
2: Restrict fluid, restrict sodium , provide 0.5 g protein/kg per day
3: Restrict fluid, restrict sodium, provide 1.5 g protein/kg per day
4: Restrict fluid, supplement sodium, provide 1.0 g protein/kg per day

Answer 38

3: Restrict fluid, restrict sodium, provide 1.5 g protein/kg per day

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.

Question 39

Arginine supplementation should be used most cautiously in which of the following patients?
1: Short Bowel
2: Cirrhotic patients
3: Septic shock patients
4: Immunocompromised patients

Answer 39

3: Septic shock patients

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.

Question 40

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

4: 600 cm

The normal length of the small intestine in adults ranges from 300 to 600 cm. Factors such as bowel length, specific segment of the small bowel that has been resected, residual disease in the remaining intestine, absence of colon and/or ileocecal valve, and prior gastric resection will have an impact on the absorptive function of the bowel.
Patients with <100 cm of small intestine to an end jejunostomy or ileostomy will require long-term parenteral nutrition (PN) support. The presence of an ileocecal valve and colon significantly improves fluid and electrolyte absorption as well as uptake of short-chain fatty acids and may allow for survival without PN with as little as 50 cm of small bowel.

Question 41

What is the primary fuel of the colonocytes?
1: Medium chain fatty acids
2: Glucose
3: Glutamine
4: Short chain fatty acids

Answer 41

4: Short chain fatty acids

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.

Question 42

Dietary fat is predominately absorbed in what part of the gastrointestinal tract?
1: Ileum and colon
2: Stomach and duodenum
3: Distal jejunum and ileum
4: Duodenum and proximal jejunum

Answer 42

4: Duodenum and proximal jejunum

Dietary fat is absorbed in the proximal small bowel. Lingual lipase released in the mouth and gastric lipase produced in the stomach have a limited role in fat digestion in healthy adults. Bile acids secreted by the liver as well as lipase and colipase produced by the pancreas aid in the micellar solubilization and absorption of dietary fat.

Question 43

Gastrectomy patients are at risk for a deficiency of which vitamin?
1: B12
2: Folic Acid
3: Thiamine
4: B6

Answer 43

1: B12

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

Which of the following areas of the gastrointestinal tract has the LEAST impact on nutrient absorption and intestinal adaptation following significant intestinal resection?

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

Answer 44

3: Jejunum

Resections of the proximal bowel, including the duodenum and proximal jejunum, are generally better tolerated because of ileal compensation and adaptation. Ileal resections are generally more poorly tolerated than jejunal resections because adaptive hyperplasia in the remaining jejunum is limited. The ileocecal valve slows intestinal transit allowing for greater absorption of nutrients. The colon has critical roles in fluid and nutrient absorption. Therefore, patients lacking a colon are at greater risk of dehydration. Furthermore, the colon is capable of salvaging calories through anaerobic bacterial fermentation of undigested carbohydrates into absorbable short-chain fatty acids (SCFAs).

Question 45

Which of the following is associated with adaptation to starvation?
1: Increased glycogenesis
2: Increased lipid oxidation
3: Decreased gluconeogenesis
4: Increased glucose oxidation

Answer 45

2: Increased lipid oxidation

During fasting, fuel oxidation gradually shifts from carbohydrates to mainly lipids as oxidative source. Lipolysis increases strongly and provides the body with fatty acids. As a consequence of increased fatty acid oxidation, terminal glucose oxidation is decreased. Endogenous glucose production by gluconeogenesis provides the body with sufficient glucose for glucose-dependent processes. Glucose is still used for glycogen synthesis but to a lesser degree.

Question 46

How much fluid per day is required to maintain fluid balance?
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

2: 30-40 mL/kg/day

Water intake is derived primarily from the diet, whereas various sources of water losses contribute to total fluid output. In most cases, sensible losses from the gastrointestinal tract and kidneys account for the majority of fluid loss. Insensible losses from the lungs and skin can contribute up to 1L per day. Fluid gains should be in balance with fluid losses over a period of several days. The average healthy adult will require 30-40 mL/kg/day to maintain this balance.

Question 47

Valproic acid 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

2: Carnitine

Valproic acid, an antiepileptic drug, has been shown to induce carnitine deficiency. The mechanism of valproic acid induced carnitine deficiency or changes of each acylcarnitine are still under investigation. 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

Question 48

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

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

Answer 48

2: Folate

The chemotherapeutic drug methotrexate is a folate analogue that became available in the early 1950s. Methotrexate is structurally similar to folate. It competitively inhibits dihydrofolate reductase, an enzyme that catalyses the conversion of dihydrofolate to tetrahydrofolate, a cofactor in the synthesis of purine nucleotides and thymidylate. Therefore, Methotrexate impairs malignant growth by interfering with DNA synthesis, repair and cellular replication

Question 49

Which of the following statements best describes the human gut microbiota?
1. The human gut microbiota is established by the age of 3 years and few factors influence it.
2. Trillions of bacteria currently comprise the human gut microbiota.
3. The human gut microbiota is highly dependent on the host for survival but provides little benefit to the host.
4. The human gut microbiota is not influenced by the mode of infant delivery

Answer 49

2. Trillions of bacteria currently comprise the human gut microbiota.

Humans are sterile in utero and are first colonized depending B on the mode of delivery. The gut microbiota development increases as the diet increases in complexity. The colonization of gut microbiota is influenced primarily by undigested polysaccharides that ferment to produce SCFAs. The SCFAs serve many biological functions in the host’s body. The gut microbiota also has many other positive benefits to the host.

Question 50

Which of the following statements best describes a probiotic?

1. A probiotic is a live organism used to make yogurt.
2. A probiotic is a “live nonpathogenic organism (bacteria or yeast) which when administered in adequate amounts confers a health benefit on the host.”
3. Probiotics are on the Generally Recognized As Safe (GRAS) list and therefore can be safely provided to all humans receiving nutrition support therapy.
4. The mechanisms of probiotics are well known, making probiotic therapy a great addition to
   nutrition support therapy.

Answer 50

2. A probiotic is a “live nonpathogenic organism (bacteria or yeast) which when administered in adequate amounts confers a health benefit on the host.”

The correct answer is B. While the starter cultures used to make yogurt, Lactobacillus bulgaricus and Streptococcus thermophilus, are on the GRAS list and therefore considered safe for human consumption, they are not probiotics. There are specific criteria that a bacterium must meet to be considered a probiotic. The mechanisms of action of probiotics are still being researched, but what is known is that each strain of bacteria behaves differently, particularly in different environments. Therefore, a general application of probiotic therapy for nutrition support patients is not recommended.