Nutrition Flashcards
What is the difference between SGA vs IUGR?
SGA - BW <10% ile, can be constitutional and NOT NECESSARILY PATHOLOGIC
IUGR - fetus has not reached its growth potential due to pathological factors (ex: suboptimal in utero- placental environment, genetic factors (fetus) or maternal factors
Difference between whey and casein?
Whey has greater cysteine and less methionine than casein
Both are major protein sources in neonates
What are whey to casein ratios in Colostrum? Mature milk? Casein based formulas? Whey based formulas? Preterm milk?
Whey:Casein
Colostrum 80:20
Mature milk 55:45
Casein based formulas 20:80
Whey based formulas 60:40
Whey is the liquid portion after the milk curdles - that is why BF babies poop after every feed (faster transit time due to whey)
Cysteine is a substrate for glutathione (higher with whey)
Curdles is casein (Lower solubility at pH 4.6)
Preterm milk 60:40
Who is at risk for Vit B12 deficiency?
Folate deficiency?
Risk of Vitamin B12 deficiency in breast-fed infants of vegetarian mothers who do not ingest eggs or dairy products
- anemia
- associated with methylmalonic acidemia and homocystinuria
Risk of folic acid deficiency in infants fed only evaporated milk or goat’s milk
- poor weight gain, anemia;
- often coexists with iron deficiency
Risk for pyloric stenosis (PS) ?
If Mother has PS - 19% if boy, 7% if girl
If Father has PS - 5.5% if boy, 2.4% if girl
Sibling has PS - 4% if boy, 2.4% if girl
What are the fetal energy sources?
2/3 Maternal glucose (facilitated diffusion)
1/4 Placental lactate
Rest: Maternal amino acids (active transport)
How does TBW, ECF, ICF Na and Chloride content change w increasing GA?
TBW ECF Na and Cl decrease ICF increases (so does protein, fat, iron, Ca, Ph)
Name the Essential amino acids?
PVT TIM HALL
Phenylalanine
Valine
Threonine
Tyrosine
Isoleucine
Methionine
Histidine
Arginine (only if + nitrogen balance)
Leucine
Lysine
Which are critical fatty acids transferred across placenta to fetus?
Arachadonic acid and docosahexanoic acid (DHA)
Increases in 3rd trimester
Biomagnification-higher values in cord blood then maternal circulation
Critical for brain and eye development
Name the 2 essential fatty acids?
Linoleic and alpha linolenic acid
Which are the 2 most prevalent fatty acids in human milk?
Oleic
Palmitic acid
How long does it take to develop essential fatty acid deficiency?
Short delay of 3-7 days without providing linoleic and alpha linolenic acid
Neonate with scaly dermatitis, alopecia, thrombocytopenia and FTT. Dx?
Essential fatty acid deficiency
Diagnostic test:
Triene:tetraene ration>0.2 (might also describe as increase mead acid (triene) and decreased arachadonic acid (tetraenoic)
Can be prevented w as little as 0.5-1g/kg/day of intralipid
For a positive nitrogen balance how many grams of glucose must be provided per gram of protein?
6g glucose for 1g of protein
Carbs should provide 35-65% total cals
Fats 30-50%
Protein 7-15%
Tissue richest in long chain PUFAs?
Retina
Long chain polyunsaturated fatty acids are needed in the development of _____.
Brain
Neural tissue
Eyes
*specifically AA (arachidonic acid) and DHA
Which trace element in excess amount can cause neurotoxicity?
Manganese-deposition in basal ganglia leading to injury
Copper causes cirrhosis of liver
Chromium-renal failure
Zinc-decrease leukocyte and phagocyte activity
Which amino acid is needed for synthesis of glutathione?
Cysteine
What form of Vit D reflects a baby’s Vit D levels?
25 hydroxyvitamin D
Due to it’s longer half life
Folates are responsible for degradation of which amino acids
Homocysteine
Histidine
Folate is responsible for the synthesis of ________.
Purines
Pyrimidines
AA (serine and methionine)
Which GA is the highest growth rate?
32-36 weeks (peaks 31g/day)
What are the hormonal factors that affect growth?
Increase in GH and placental lactogen
Increase in glucose and lipid concentrations to stimulate fetal insulin production, fetal growth, adipose tissue, and restricts protein degradation
PL appears to be mediated by insulin-like growth factors
Estimated fetal energy expenditure?
35-55kcal/kg/day
Source Maternal glucose (2/3)-facilitated Placental lactate (1/4) Maternal AA (rest)-active
Which AA are glucose precursors?
Alanine
Glutamic acid
Aspartic acid
What are neonatal caloric requirements?
120-150 kcal/kg/d
To allow energy expenditure and growth
Which pancreatic proteases are decreased in PT and term babies
Trypsin’s and chymotrypsin
Describe fat digestion
(1) bile acid emulsification of fat globules (form micelles)
(2) triglyceride hydrolysis by lipase
(3) fatty acid transfer across intestinal mucosa
PT and FT infants have decreased bile acids and pancreatic lipases
Which FA are absorbed directly into blood? How is total fat absorption not affected?
• Short and Medium-chain fatty acids are absorbed directly into the blood via intestinal capillaries and travel through the portal vein.
Bile acids are not needed
for short or medium chain fatty acid processing.
• Despite reduced bile acids and pancreatic lipase, total fat malabsorption is
minimized:
• Lingual lipase, gastric lipase
• Lipase in breast milk
Carbohydrate Metabolism in Neonate
Salivary & Pancreatic Amylase
hydrolyzes starch, glycogen, and
dextrin to glucose, maltose, and
limit-dextrins: decreased secretion in newborn
Glucosidases (lactase, sucrase,
maltase, isomaltase) adult levels at 28 weeks*
Lactase adult levels at 36 weeks
Glucose transport across epithelium less efficient in newborn, especially
PT
Colonic salvage pathway: microflora
ferments non-absorbed nutrients to energy-rich products that are
ahsorhed hv the colon
Composition of human milk
Fat globules cholesterol and Phospholipids
Micelles
Cells
Aqueous phase
Which is the primary carbohydrate in human milk?
Lactose
Human milk oligosacharides
Protein delivers 75% nitrogen
Fat provides 50% of calories
What makes up mother’s milk?
• Lactose is primary carbohydrate
Protein delivers 75% of nitrogen
Fat provides 50% of calories
Major Fats in human milk
Fat
Short-chain and Medium chain FA (mature Gi tract)
Long chain FA, sphingomyelins and cholesterol (CNS myelination)
Fat breakdown in milk
Fat
Greatest source of energy (50-60% caloric intake)
• Highly variable component
Transfer of fat soluble vitaminds
Some fatty acids have antimicrobial properties
Short Chain FA
Maturation of the gastrointestinal tract
Peripheral glucose utilization
Médium chain FA
Maturation of the gastrointestinal tract
Long Chain FA
Infant visual and neural development
Antiviral and antiprotozoal effects
Modulate the immune system
Sphingomyelin
Central nervous system myelination
Neurobehavioral and visual development
Cholestérol
Decreases as lactation progresses
Major proteins in human milk
Casein-AA, Micelle has Ca/Ph Lactoferrin-iron binding, antimicrobial effect Secretory IGA- neutralizes toxins Mucins-binge pathogens Cytokins Growth factors
Preterm milk
Higher in protein (decreases over time)
Preterm and term milk changes over time?
Highest in protein in 1st week
Then energy increases and fat
Immune Components that are HIGHER in preterm breast milk?
ß-defensin 1 (colostrum and mature milk)
CD 14 receptor
Transforming growth factor- ß2 (colostrum)
• Lysozyme (equivocal)
Compared to human milk, what does formula have more of?
Compared to human milk, formula is higher in sodium, calcium, potassium, chloride, magnesium, phosphorus, and most amino acids
Formula is lower in
cholesterol
What’s the role of prolactin and oxytocin in breastmilk production?
Prolactin is involved in synthesis (anterior pituitary)
Oxytocin in milk ejection (post pituitary)
Benefit of DMB over formula
Decrease risk for NEC
How does pasteurization affect donor milk?
Decrease in water soluble vitamins
Mother’s milk has which medical benefits compared to DBM?
Decreases in NEC, Late onset sepsis, feeding intolerance and ROP
DBM decreases only NEC
Omegaven vs SMOF
SMOF 1/4 Soy bean 1/4 MCT 1/4 olive oil 1/4 Fish oil
Omegaven
Fish oil
Describe the role of trace elements
Chromium: Role in insulin metabolism/glucose regulation
Copper: Impt for Hb formation/Fe absorption/oxidative metabolism/myelination, Deficiency > anemia, neutropenia, osteoporosis, hypotonia, hair/skin depigmentation, poor weight gain
Manganese: Role in enzymatic systems for bone growth, Role in enzyme activation (superoxide dismutase, pyruvate carboxylase)
Selenium: Cofactor for glutathione peroxidase, preterm < term levels at birth, Deficiency > cardiomyopathy
Zinc: Impt in gene expression, neurotransmission, apoptosis, metabolism of protein CHO & lipids; interferes with Cu absorption, Deficiency- rash, alopecia, diarrhea, FT, oral candidiasis/Staph, irritability, photophobia
Congenital > Acrodermatitis Enteropathica- AR, abl absorption/transport (nail dysplasia/ocular findings)
Acquired > Premature at risk, Maternal Def (assoc w/ IUGR), malabsorption
Responds well to zinc supplementation, dermatitis resolves in days
Mothers own milk is better than donor breast milk
T or F
True
How does PT formula compare to human milk?
Energy in PT matches Human milk
Protein similar as early HM
Carb content higher than human milk
Fat matches Hm after first week of lactation
Lipase is not present in formula
T or F
True
With hypoalbunemia, how does Ca get affected?
For every 1g of Albumin that is low your Ca drops by 0.8
Why are newborns predisposed to Vit K deficiency?
Initial lack of GI microorganism that synthesize vitamin K
Immature newborn liver
Maternal meds (anticonvulsants, warfarin and anti-tuberculosis meds)
Which vitamin deficiency is associated with pyruvate dehydrogenase complex defiency and maple syrup urine disease?
Vitamin B1 (thiamine)
Which is common vitamin b deficiency in homocystinuria?
Vitamin B6 (pyridoxine)
Which trace element deficiency is associated with anemia, neutropenia, depigmentation of hair and skin?
Copper
Which hormones augment breast growth and ductal system branching?
Estrogen and human placental lactogen
Which hormone stimulate milk production and which one promotes release?
Prolactin (from anterior pituitary) stimulate milk production
Oxytocin (post pituitary) promotes milk release with smooth muscle contraction
Which trace elements should you adjust with cholestasis?
Decrease manganese and copper
Increase zinc
Which trace elements should you change in TPN with renal insufficiency?
Chromium and selenium
What component in PN is thought to contribute to cholestasis?
Phytosterols from soybean oil in intralipid
Reasons for decreased milk supply in exclusively pumping mothers of preterm babies
Ineffective pumping
Tight breast shield
Progesterone based contraception
Breast milk is screened for
HIV
HTLV
Hepatitis B & C
Syphilis
Where is zinc predominately stored
Bone (40%)
Liver (25%)
Highest concentratuon of LCPUFA?
Brain (greatest in synapses)
Eyes (photoreceptor cells)
Pasturization decreases _____ in human milk
Eliminates HIV + CMV
Decreases lactoferrin, IgA, lysozymes
What are the three major roles of glucose in fetal life?
Acquired glucose has three major roles in fetal life:
• Glycolysis (major pathway for fetal glucose utilization)
• Carbon source (essential for fetal growth)
Glycogen storage
When does lactase reach adult levels?
36 weeks gestation
What characteristics do preterms have that affect fat digestion and absorption?
Reduced bile acid secretion
Decrease pancreatic lipase activity
Total fat malabsorption is reduced bc of lingual lipase gastric lipase ans lipases in breastmilk->aid TG breakfown
More easily digestible MCTs in BM however, (arachadonic acid and docosahexaenoic acid) not hydrolyzed or absorbed well
TEF Incidence and GA when abnormality occured?
1/4500
Often isolated, think vacterl
Abnormality during 4 week of gestation
Can p/w polyhydramnions prenatally
Which hormones induce breast growth and ductal’ system branching
Estrogen
Human placents’ lactigen
What hormone chsnges happen with breastfeeding at birth
Decrease estrogen
Decrease progesterone
Prolactin released (ant pituitarty)
Oxytocin increases (helps with augmenting contractions and ejection of milk)
Optimal position for picc placement in UE and LE placement
UE between T3-T5
LE T8-T10, if below L4 its peripheral
Which amino acid is NOT present in TPN?
Glutamine
Aspartate
Which are the essential amino acids present in preterms?
Cysteine
Arginine
Tyrosine
Which component of human milk us known for prebiotic effects? Ie to stimulate growth or activity of desired intestinal bacteria?
Human milk oligosaccharides (maintained despite pasteurization so present in donor milk)
Promotes growth of select bifidobacteria which tighten mucosal ohysical barriers, compete w pathogenic bacteria and bind to toll-like receptors.
Describe role of lactoferrin
Proteolysis resistant iron binding glycoprotein in human milk
Its bacteriocidal, antiviral and immunomodulating
Adsorbs enteric iron and prevents pathogenic bacteria from obtaining iron needed for survival
Which component of human milk increases progressively after 6 months, aiding host defense of maturing infant?
Lysozyme
Has bactericidal and antiinflammatory effects
Cleaves bacterial cell walls of GP and GN bacteria
Dermatitis, mucositis, seizures, which vitamin deficiency?
B6 (pyridoxine)
Associated with homocystinuria
Alopecia, dermatitis, scaling, seborrhea. Which vitamin deficiency?
Biotin
Associated w biotinisaae deficiency, propionic acidemia and pyruvate dehydrogenase complex deficiency
Poor wound healing and bleeding gums. Vitamin deficiency?
Vitamin C (ascorbic acid)
Associated with transient tyrosinemia
Vitamin B1 (thiamine) deficiency is assoc’s with _____?
Pyruvate dehydrogenase conpmex deficiency
MSUD
Vitamin B2 (riboflavin) deficiency us assoc’d with _____?
Glutaric acuduria type 1
Holder pasteurization process destroys which components of breastmilk
IgM
ECF:ICF in 24 weeker vs term. When do the volumes become equivalent?
Preterm 24 weeks 65:25
Term 45:35
3 months 35:35
