Fiser.10.Nutrition Flashcards
1
Q
What is your daily caloric need (kg/day)
A
20-25 calories/kg/day
2
Q
How many calories per gram in fat?
A
9 calories / gram
3
Q
How many calories per gram in protein?
A
4 calories / gram
4
Q
How many calories per gram in PO carbohydrates?
A
4 calories per gram
5
Q
How many calories per gram in dextrose?
A
3.4 calories per gram
6
Q
What percent of calories should come from protein / fat /carbohydrates for a healthy adult male?
A
20% protein, 30% fat, 50% carbohydrates
7
Q
How many g protein / kg / day?
A
1g protein / kg/day
8
Q
What percent of protein intake should be essential amino acids?
A
20%
9
Q
What molecule is provided by fat intake?
A
Essential fatty acids
10
Q
How much can trauma increase your caloric requirement?
A
20-40%
11
Q
How much can surgery increase your caloric requirement?
A
20-40%
12
Q
How much can sepsis increase your caloric requirement?
A
20-40%
13
Q
How much can pregnancy increase your caloric requirement?
A
300 kcal per day
14
Q
How much can lactation increase your caloric requirement?
A
500 kcal per day
15
Q
Which of the following increase your protein requirement: trauma, surgery, sepsis, pregnancy, lactation?
A
All of the above – trauma, surgery, sepsis, pregnancy, lactation `
16
Q
What is the formula to calculate caloric requirements with burns
A
25 kcal/kg/day + (30 kcal/day * % burn)
17
Q
What is the formula to calculate protein requirement for burn patients?
A
1-1.5 g/kg/day + (3g x % burn)
18
Q
What is the majority of energy expenditure for burn patients?
A
Heat production
19
Q
What percent of basal metabolic rate increases with each degree of fever?
A
10% for each degree above 38.0 degrees celsius
20
Q
How do you calculate caloric need for overweight patients?
A
Weight =[(actual weight – IBW) * 0.25] + IBW
21
Q
What does the Harris-Benedict equation calculate?
A
Calculates basal energy expenditure based on weight, height, age, and gender
22
Q
What is the nutritional basis of central line based TPN?
A
Glucose based
23
Q
What is the maximal rate of glucose administration for central line TPN?
A
3 g / kg/hr
24
Q
What is the nutritional basis of PPN?
A
Fat-based
25
What cells are fed by short-chain fatty acids? Give an example
Butyric acid, fuel for colonocytes
26
What cells are fed by glutamine?
Small bowel enterocytes
27
Name two locations where glutamine is the most common amino acid?
Blood and tissue
28
How does glutamine help with nitrogen excretion?
Releases NH4 in the kidney
29
How does glutamine help in glucose balance
Can be used for gluconeogenesis
30
How is glutamine used with neoplastic cells?
Primary fuel for neoplastic cells
31
What is the half life of albumin?
18 days
32
What is the half life for transferrin
10 days
33
What is the half life for prealbumin
2 days
34
What is a normal protein level?
6.0 - 8.5
35
What is the normal albumin level?
3.5-5.5
36
Name three acute indicators of nutritional status
Retinal binding protein, prealbumin, transferrin
37
How do you calculate ideal body weight for men?
106 lb + 6 lb for every inch over 5 ft
38
How do you calculate IBW for women?
100 lb + 5 lb for every inch over 5 ft
39
What amount of preop weight loss is an indication of poor nutritional status?
Acute weight loss \> 10% of total body weight in 6 months
40
What weight as a percent of IBW is an indicator of poor nutritional status?
Weight \< 85% of IBW
41
What albumin level is an indicator of poor nutritional status?
Albumin \< 3.0
42
What are patients with low preop albumin levels at increased risk of postop?
Increased risk of periop morbidity and mortality
43
What does the ratio of CO2 produced to O2 consumed measure?
Measurement of energy expenditure
44
What does respiratory quotient (RQ) \> 1 indicate?
Lipogenesis and overfeeding
45
How do you treat an RQ \> 1
Reduce carbohydrates and caloric intake
46
What does a RQ \< 0.7 indicate?
Ketosis and fat oxidation (starvation)
47
How do you treat RQ \< 0.7?
Increase carbohydrate and caloric intake
48
What is the RQ for pure fat utilization?
RQ \< 0.7
49
What is the RQ for pure protein utilization?
RQ = 0.8
50
What is the RQ for pure carbohydrate utilization?
RQ = 1.0
51
Which postop days are the “diuresis phase”?
Postop days 2-5
52
What postop days are the catabolic phase?
Postop days 0-3
53
What postop days are the anabolic phase
Postop days 3-6
54
What is the nitrogen balance during the catabolic vs anabolic phases?
Catabolic = negative nitrogen balance Anabolic = positive nitrogen balance
55
In the injured patient, what is the magnitude of metabolic response proportional to?
Proportional to the degree of injury
56
What proportion of glycogen is stored in skeletal muscle versus the liver?
2/3 in skeletal muscle; 1/3 in liver
57
How much time before glycogen stores are depleted?
24-36 hours of starvation
58
What energy source does the body switch to after glycogen stores are depleted?
fat or fat/protein depending on underlying cause
59
what happens to basal metabolic rate in starvation vs injury?
stays the same in starvation, increased BMR in injury
60
what happens to [x] of TNF and IL1 in starvation vs injury?
not present in starvation, increased in injury
61
what is the main fuel oxidized in starvation vs injury
fat is oxidized in starvation and mixed fat/protein are oxidized in injury
62
what happens to ketone body production in starvation vs injury?
very high ketone body production in starvation vs no change/small increase in injury
63
what is the gluconeogenesis activity in starvation vs injury?
GN is slightly increased in starvation and very increased in injury
64
what happens to protein metabolism in starvation vs injury?
protein metabolism is slightly increased in starvation and way increased in injury
65
what happens to negative nitrogen balance in starvation vs injury?
there is a slight increase in NNB in starvation versus a big increase in NNB in injury
66
what happens to hepatic ureagenesis in starvation vs injury?
there is a slight increase in hepatic ureagenesis in starvation versus a big increase in injury
67
what happens to muscle proteolysis in starvation vs injury?
there is a slight increase in muscle proteolysis in starvation versus a big increase in injury
68
what happens to hepatic protein synthesis in starvation vs injury
there is a slight increase in hepatic protein synthesis in starvation versus a big increase in injury
69
Where is glucose 6 phosphate located?
in the liver only
70
Where does glucose 6 phosphate go during starvation?
Enters the skeletal muscle after breakdown from glycogen and stays there
71
Name four gluconeogenesis precursors
Alanine, lactate, pyruvate, glycerol
72
Which amino acids increase in times of stress?
Alanine and phenylalanine only
73
Which organ performs gluconeogenesis in late starvation?
kidney
74
Why does protein-conservation not occur after trauma or surgery?
Catecholamines and cortisol
75
Does protein conservation occur with starvation?
yes
76
What is the main source of energy with starvation and trauma? How do these energy sources differ between starvation and trauma?
Main energy source is ketones from fat with starvation, after trauma it is more mixed (fat + protein)
77
What percent weight loss can patients tolerate without complication?
15% weight loss
78
How many days can postop patients tolerate NPO status?
7 days
79
What should you do after 7 days of postop NPO status?
TPN or DHT
80
What are two reasons it is preferable to feed the gut over TPN
TPN-related complications; Prevent bacterial translocation from the gut
81
What is the MOA of bacterial translocation during starvation?
Bacterial overgrowth + increased permeability due to starved enterocytes --\> bacteremia
82
Name two indications for a PEG tube
PO feeding not possible ever (s/p CVA) or not expected to occur \> 4 weeks
83
What fuel source does the brain use in starvation
Glucose --\> ketones with progressive starvation
84
Name four obligate glucose users
Peripheral nerves, adrenal medulla, RBCs, WBCs
85
How does the hypothalamus respond to trauma? (3)
Releases ACTH (adrenocorticotropic hormone), ADH, and GH (growth)
86
What is released locally by injured tissue? (3)
Cytokines, prostaglandins, platelet-activating factor
87
How do the kidneys respond to trauma
Volume-conserving mechanisms with aldosterone and ADH
88
Name the two humoral cascades triggered by trauma
Complement and kinins
89
How does the skeletal muscle respond to trauma?
Mobilizes amino acids
90
How does the pancreas respond to trauma?
Increase glucagon, decrease insulin
91
How does the heart respond to trauma?
Increased stroke volume and increased heart rate
92
How do the adrenals respond to trauma
Increase cortisol and catecholamines
93
Why does peripheral vasoconstriction occur with trauma?
Redistributes blood to vital organs
94
name the homeostatic adjustments of the hypothalamus, heart, adrenals, pancreas, kidney, inflammatory system, and peripheral vasculature to trauma
see pic
95
When does refeeding syndrome occur?
After prolonged malnutrition / starvation
96
Which electrolytes are altered in refeeding syndrome?
Decreased K, Mg, Phos
97
What are the effects of refeeding syndrome on the organs?
Cardiac dysfunction, profound weakness, encephalopathy
98
How do you prevent refeeding syndrome?
Refeed at low rate (1—15kcal/kg/day)
99
What is the MOA of cachexia?
Anorexia, weight loss, wasting mediated by TNF-alpha --\> glycogen breakdown, lipolysis, protein catabolism
100
What is the difference between kwarshiorkor and marasmus?
Kwarshiorkor is protein deficiency and marasmus is starvation
101
How much protein do you need to get 1g of nitrogen?
6.25 g protein contains 1 g nitrogen
102
What is the formula for nitrogen balance?
(N in – N out) = ([protein/6.25] – [24 hour urine N + 4g])
103
Define the difference between positive and negative nitrogen balance
Positive N balance = anabolism (more protein ingested than excreted). Negative N balance = catabolism (more protein excreted than ingested)
104
What is the rate of total protein synthesis (in g/day) for a healthy 70kg male?
250g/day
105
How does the liver interact with amino acids?
Liver responsible for amino acid production and breakdown
106
What is the function of urea?
Breakdown product of amino acids made in the liver to get rid of ammonia
107
What amino acids are the result of majority of protein breakdown in skeletal muscle? (2)
Glutamine, alanine
108
Name three subtypes of fats
Triacylglycerides (TAG), cholesterol, lipids
109
What three enzymes digest fat and what are the breakdown produts?
Pancreatic lipase, cholesterol esterase, phospholipase to micelles and free fatty acids
110
What are the three components of micelles?
Bile salts, long-chain free fatty acids, and monoacylglycerides
111
How do micelles enter enterocytes?
Fuse with membrane
112
What are the two functions of bile salts
Increase absorption area of fats, help form micelles
113
How is cholesterol related to bile salts?
Cholesterol is used to synthesize bile salts
114
What are the four fat-soluble vitamins and how are they absorbed
A, D, E, K – absorbed in micelles
115
How do medium-chain fatty acids enter the enterocyte?
Simple diffusion
116
How do short-chain fatty acids enter the enterocyte?
Simple diffusion
117
What are the components of chylomicrons and their percentages?
90% triacylglycerides, 10% phospholipids/protein/cholesterol
118
Where do chylomicrons go after forming in the enterocyte?
Enter the lymphatics via thoracic duct
119
What happens to LCFA after they enter enterocytes?
Enter lymphatics along with chylomicrons
120
What happens to MCFA after they enter enterocytes?
Enter the portal system
121
What happens to SCFA after they enter enterocytes?
Enter the portal system
122
What happens after amino acids enter enterocytes?
Enter the portal system
123
What happens to carbohydrates after they enter enterocytes?
Enter the portal system
124
Where is lipoprotein lipase located (2)?
Endothelium of liver; Adipose tissue
125
What are the substrates (2) of lipoprotein lipase and its breakdown products (2)?
Clears chylomicrons and TAGS from blood, breakdown into fatty acids and glycerol
126
Where is “free fatty acid binding protein” located?
On endothelium of liver and adipose tissue
127
What are the (2) substrates of free fatty acid binding protein?
Binds SCFA and MCFA
128
Which two types of muscle use saturated fatty acids for fuel
Cardiac muscle, skeletal muscle
129
Name the two MC ketones
Acetoacetate, beta-hydroxybutyrate
130
Which four organs prefer ketones / fatty acids for fuel?
Colonocytes, liver, heart, skeletal muscles
131
What is the function of unsaturated fatty acids?
Structural components for cells
132
Where is hormone-sensitive lipase located?
In fat cells
133
What is the storage form of fat?
triacylglycerides
134
Which hormones is hormone-sensitive lipase reactive to? (3)
Growth hormone, catecholamines, glucocorticoids
135
What is the substrate and 2 products of hormone-sensitive lipase and what does it do with its products?
Breaks down triacylglycerides to fatty acid and glycerol, released into bloodstream
136
Name the two essential fatty acids
Linolenic, linoleic fatty acids
137
What are the two functions of essential fatty acids
Needed for prostaglandin synthesis (LCFA); important for immune cells
138
Name the three enzymes and the order they are encountered for carb digestion
Salivary amylase then pancreatic amylase and disaccharidases
139
How does glucose enter the enterocyte?
Secondary active transport
140
How does galactose enter the enterocyte?
Secondary active transport
141
How does fructose enter the enterocyte?
Facilitated diffusion
142
Where are fructose, glucose, and galactose released after entering the enterocyte?
Portal venous system
143
What monosaccharides make up sucrose?
Fructose + glucose
144
What monosaccharides make up lactose?
Glucose + galactose
145
What monosaccharides make up maltose?
Glucose + glucose
146
What are the four protein digestion enzymes and in which order are they encountered?
Stomach pepsin --\> trypsin, chymotrypsin, carboxypeptidase
147
What is the MOA of trypsin activation?
Trypsinogen is released by pancreas and activated by enterokinase, released from duodenum
148
Which molecules does trypsin activate
Activates other pancreatic protein enzymes; Can autoactivate other trypsinogen molecules
149
What are the three breakdown products of protein by proteases?
Amino acids, dipeptides, and tripeptides
150
How are amino acids, dipeptides, and tripeptides absorbed by enterocytes?
Secondary active transport
151
Where are amino acids released from enterocytes?
Into the portal vein
152
Why do you limit protein intake in patients with liver or renal failure?
Prevent buildup of ammonia that could lead to worsening encephalopathy
153
Name the three branched chain amino acids
Leucine, isoleucine, valine (LIV)
154
Where are BCAAs metabolized?
In the muscle
155
What disease process are BCAAs potentially important for?
liver failure
156
Are BCAAs essential amino acids?
yes
157
Name the 10 essential amino acids
PRIVATE TIM HALL (PVT TIM HALL) Phenylalanine; Valine; Threonine; Tryptophan; Isoleucine; Methionine; Histidine; Arginine; Lysine; Leucine
158
What percent of TPN is amino acid solution?
10%
159
What percent of TPN is dextrose solution?
50%
160
What 7 electrolytes are included in TPN
Na, Cl, K, Ca, Mg, PO4, acetate
161
Are vitamins and minerals included in TPN
Yes
162
How are lipids administered in TPN patients?
Separately from TPN
163
How many calories per cc in a 10% lipid solution?
10% lipid solution with 1.1kcal/cc
164
How many calories per CC in a 20% lipid solution?
2 kcal / cc
165
What are the sx of a chromium deficiency? (3)
Hyperglycemia, encephalopathy, neuropathy
166
Sx of selenium deficiency? (2)
Cardiomyopathy, weakness
167
Sx of copper deficiency? (1)
pancytopenia
168
Sx of zinc deficiency? (1)
poor wound healing
169
Sx of phosphate deficiency? (3)
Weakness, encephalopathy, decreased phagocytosis
170
How would weakness a/w phosphate deficiency affect a ventilated ICU pt?
Failure to wean off vent
171
Sx of thiamine (B1) deficiency? (2)
Wernicke’s encephalopathy, cardiomyopathy
172
Sx of pyridoxine (B6) deficiency? (3)
Sideroblastic anemia, glossitis, peripheral neuropathy
173
What is sideroblastic anemia?
Bone marrow produces ringed sideroblasts instead of normal erythrocytes
174
Sx of cobalmin (B12) deficiency? (3)
Megaloblastic anemia, peripheral neuropathy, beefy tongue
175
Sx of folate deficiency (2)?
Megaloblastic anemia , glossitis
176
Sx of niacin deficiency (3)?
Pellagra: diarrhea, dementia, dermatitis
177
Sx of essential fatty acid deficiency? (3)
Dermatitis, hair loss, thrombocytopenia
178
Sx of vitamin A deficiency? (1)
Night blindness
179
Sx of vitamin K deficiency? (1)
coagulopathy
180
Sx of vitamin D deficiency? (3)
Rickets, osteomalacia, osteoporosis
181
Sx of vitamin E deficiency? (1)
neuropathy
182
Which part of the cori cycle occurs in muscle
Glucose is utilized and converted to lactate
183
What does the liver do in the cori cycle
Lactate goes to the liver and is converted back to pyruvate and then glucose via gluconeogenesis
184
Where does the glucose generated via gluconeogenesis go?
Back to the muscle
