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Indications for TPN
A. Premature infants <30 weeks gestation and/or <1500g.
B. >30 weeks gestation but unlikely to achieve full enteral feeds by day 5.
C. Infants at high risk of NEC:1. <30 weeks gestation
2. >30 weeks with absent or reversed fetal umbilical artery flow.
3. Infants with perinatal asphyxia
D. Necrotising enterocolitis (NEC).
E. Gastro-intestinal tract anomalies.
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GOALS OF PN PN is initiated to correct in-utero growth
restriction PN to prevent subsequent growth failure. PN to provide
1. sufficient energy and nitrogen
2. to prevent catabolism and
3. to achieve positive nitrogen balance
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ADMINISTRATION
PN which include:
1. Route of administration
2. Content of PN based upon the timing of administration
3. Monitoring
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Components of TPN
1. Fluid
2. Calories (Energy)1. Carbohydrate
2. Protein
3. Lipid
3. Acetate
4. Minerals
5. Vitamins
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Energy
parenteral nutrition (PN) is calculated to provide percent of calories as
1. Carbohydrates………………………………….. 55%
2. Lipids ……………………………………………….. 30%
3. amino acids …………………………………….. 15%
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Fluid
Volumes are increased over the first 7 days in line with the feeding protocol with the aim of delivering 150 ml/kg/day by day 7.
Day 1 60 ml/kg/day Day 2-3 90 ml/kg /day Day 4-6 120 ml/kg /day Day 7 150 ml/kg /day
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Energy
Requirements; A. energy expenditure;
range of 50 to 60 kcal/kg per day
1. Basal metabolic rate2. Physical activity3. Specific dynamic action of food4. Thermoregulation
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Energy Requirements;
B. Growth;
about 5 kcal/g in utero weight gain of 14 g/kg per day energy intake of about 70 kcal/kg per day
Babies need at least 100-120 kcal/kg/day to grow.
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daily energy requirements for growing premature infants
Factor Kcal/kg CommentResting energy expenditure
50 Resting metabolic rate
Activity 15 30 percent above restingCold stress 10 ThermoregulationSynthetic effect of feeding 8 Dietary thermogenesisFecal loss 12 10 percent of intakeGrowth 25 Calories storedTotal caloric requirement
120
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Caloric balance PN preterm
Concentration, percent
g/kg/day kcal/kg/day
kcals, percent
Infusion rate at 135 mL/kg/dayGlucose 12.5 16.9 57.5 57Amino acids
2.5 3.4 13.6 13
Infusion rate at 15 mL/kg/dayLipid 20 3.0 30 30
energy sources in PN solutions based upon an assumed •Total Fluid Intake of 150 mL/kg per day and •Total Calorie Intake is 102 kcal/kg per day
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To calculate total daily calories,
use the following equation.
kcal/kg/ day =Total mL of formula x kcal/mL/Wt(kg)
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Calculate Proteins
% Amino acids = (Wt (kg) ×(g/kg/day) ×100) /
Vol in 24 h
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Calculate Fat emulsions
Fat emulsions. 10% fat emulsion (Intralipid) contains 1.1 kcal/mL 20% emulsion, 2 kcal/ mL.
Use the following formula to calculate daily caloric intake supplied by Intralipid 20%.
kcal / kq / day = (total lipid solution * 2) /wt
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CarbohydrateGLUCOSE
is administered as dextrose monohydrate.
Start with 4-6 mg/kg/min or D10-
D12.5.
Dextrose yields 3.4 kcal/g.
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Carbohydrate
Advance by 1-3 mg/kg/min daily to a maximum of 12 mg/kg/min (up to 15
mg/kg/min in selected cases). The target plasma glucose level should
be 5.5 - 9.9 mmol/L.
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GlucoseReturn to index
Carbohydrate
Potential complications/risks include: 1. Hyperglycemia or hypoglycemia
2. Glycosuria and potential osmotic diuresis
3. Cholestasis and/or hepatic steatosis with high caloric intake usually from long-term high concentration infusion.
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AMINO ACIDS Start amino acids at 1.5-2 g/kg/d
step-wise advance of protein advance by 0.5 gm/kg/d to goal as needed Maximum is 3 g/kg/d in term infants and 3.5 g/kg/d
in preterm infants. Maximum peripheral concentration 3.5%
Include protein in you calorie count. Protein yields 4 kcal/g
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AMINO ACIDS optimal mixture of essential/nonessential amino acids required to achieve a positive nitrogen balance, which
results in protein accruement and growth
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Protein
Starting amino acid / protein intake:
Amino acid supply should start on the first
postnatal day.
A minimum amino acid intake of
1.5 g/kg per day is necessary to prevent a negative nitrogen balance.
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Protein
complications/risk include:
1. Acidosis
2. Elevated BUN ; rise in urea
3. Hyperammonemia ; rise ammonia
4. high levels of potentially toxic amino acids such as
phenylalanine.
5. Cholestasis with prolonged administration
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Fat Energy source
Essential fatty acid source (intralipid)
Cell uptake and utilisation of free fatty acids is
deficient in preterm infants
Start at ; 1g/kg/day,
increasing gradually to 3g/kg/day (less if septic)
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Lipid
Daily increase in lipid starting at 1
g/kg/day, increasing by 1g/kg/day.
target of 3 g/kg per day
1 g = 6 ml from solution 20%
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Lipid
Monitor triglyceride levels with each
increase. If triglyceride levels >2.8 mmol/L, consider reducing
the lipid emulsions by 1 g/kg/day increments but aim to continue at least 0.5g/kg/day to prevent
essential fatty acid deficiency.
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Composition10 versus 20 percent IL
A. 30 percent emulsion
has not been investigated in premature infants
B. 10 percent solution
1. requires a larger administered volume
2. associated with a poorer clearance of triglycerides due to
interference from lipoprotein X
3. accumulation of lipoprotein X appears to be due to the higher ratio
of phospholipids to triglycerides in the 10 percent solution
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Composition10 versus 20 percent IL C. 20 percent IL infused lipids
demonstrated by their lower serum concentrations of
triglyceride, cholesterol, and phospholipid
have lower phospholipid-to-triglyceride ratios and
liposomal content than the 10% solutions, resulting in
lower plasma triglyceride, cholesterol, and
phospholipid concentrations.
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Fat A lipid intake of 0.25-0.5 g/kg/d is required to prevent essential
fatty acid deficiency.
Include lipid emulsion in calculations of total fluid intake.
Lipids yield 10 kcal/g.
IV lipid preparations are available as a 20% soybean emulsion that yields 2 kcal/mL.
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Fat Deliver IV lipids over 24 hours.
Do not allow lipids to exceed 60% of total caloric intake.
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FatGestation Weight/
Diagnosis Initiate(0.5 g/kg/d)
Advance by0.5 g/kg/d
Goal is3 g/kg/d
byPreterm <1,500 g, stable DOL 3 DOL 7 DOL 11
>1,500 g, stable DOL 3 DOL 4 DOL 9
Very unstable (e.g.,
severe RDS, ↑ bilirubin)
DOL 3 When status
improves
Term No pulm. disease DOL 3 DOL 4 DOL 9
Severe pulm. disease,
PPHN, MAS
Consider DOL 7 When status
improves
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Complications
1. Hyperlipidemia
2. Potential risk of kernicterus at low levels of unconjugated bilirubin As a general rule, do not advance lipids beyond 0.5 g/kg/d until
bilirubin is below threshold for phototherapy
3. Potential increased risk or exacerbation of chronic lung disease
4. Potential exacerbation of Persistent Pulmonary Hypertension (PPHN)
5. Lipid overload syndrome with coagulopathy and liver failure
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Total Parenteral NutritionTotal Parenteral Nutrition
Calculate electrolytes to add to bag DOL#1: dextrose in water with no eletrolutes is usually appropriate
except in premies with low Ca stores who may require Ca DOL#2: add electrolytes to the bag based on estimated daily
requirements and BMP Estimated Needs:
NaCl = 2-4 mEq/kg/dayKCl = 1-2 mEq/kg/day (NOTE: Do not supplement K until UOP
>1cc/kg/hr, especially in premies)Ca Gluconate =200-400mg/kg/day (NOTE: mg not mEq and Ca
cannot be infused at >200mg/kg/day through a central line)
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Minerals Premature infants require high intakes of Ca and P to mimic fetal accretion
rates. Use of calcium gluconate 75mg/kg/day and inorganic phosphate 45mg/kg/day (glucose-l-phosphate) increases solubility and resulted in increased Ca and P retention and reduced PTH.11 However, there is concern regarding precipitation of Ca and P in TPN solutions preventing higher amounts being delivered. Low AA concentrations and high temperatures (in infusion tubing in the infant humidicrib) are significant risk factors for the precipitation of the insoluble dibasic calcium phosphate that may be fatal upon intravenous infusion. The AA concentration of the TPN formula should not be less than 15 g/L (and ideally >30 g/L) when high intakes of calcium (15
mmol/L) and phosphate (16.6 mmol/L) are prescribed.
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Vitamins
• Vitamins are supplied in the in lipid emulsion (soluvit N and vitalipid).
• The table below shows the amount of vitamins supplied to infants through the proposed lipid emulsion run at 3g/kg/day
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Parenteral Calcium and Phosphorus Doses
Calcium (mEq/kg) Phosphorus
(mmol/kg)
Initiate 2 mEq/kg 1 mmol/kg
Advance every 1-2
days
0.5 mEq/kg 0.3-0.5 mmol/kg
Goal 3mEq/kg preterm)
2 mEq/kg (term)
1.5 mmol/kg preterm)
1.2 mmol/kg (term)
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Route
A. peripheral IV catheters
B. central venous catheters, usually reserved for patients requiring long-term (>2 weeks) or
C. percutaneous central venous catheters
choice is dependent upon the expected duration of PN
Line infection is the most serious complication of PN.
If possible, the continuity of PN infusion should not be interrupted to reduce the risk of infection
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Total Parenteral NutritionTotal Parenteral Nutrition
Central TPN1. Easy to meet nutrition needs2. No limits on osmolarity3. Little risk of phlebitis4. Long term use5. May require general anesthesia6. Greater risk of infection7. Increased cost8. Greater risk of mechanical injury,
air embolism, venous obstruction
Peripheral TPN1. Unable to meet needs for
Ca/Phos needs2. Maximum rate of Calcium
gluconate is 200mg/kg/d3. Maximum % dextrose is 12.5%4. Short term use5. Less risk for catheter related
infections6. Lower cost ?7. Less risk of mechanical injury, air
embolism, venous obstruction
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Constituents of PN
1. Solution A (ie amino acid solution)
2. Solution B (ie lipid)
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Solution A (ie amino acid solution)1. amino acids: Vaminolact® for children under 15kg Vamin 18 EF® for children over one year, who are fluid restricted
2. glucose and electrolytes
3. zinc, copper, selenium, manganese, fluoride, iodine and chloride: Peditrace® for children under 15kg Additrace® for those over 15kg
4. Solivito N®: water-soluble vitamins if a non lipid containing regimen
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Solution B (ie lipid)
1. lipid emulsions: Intralipid® 20 per cent SMOF® 20 per cent
2. Vitlipid N infant®: fat-soluble vitamins
3. Solivito N®: water-soluble vitamins if a lipid containing regime
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METABOLIC MONITORING Test Initial When stableElectrolytes,BUN/creatinine
Daily 2-3x/week
Chemstrip/glucose q6hr-daily Daily, more frequently when changing CHO
Calcium, ionized ,total calcium, phosphorus,magnesium, bilirubin (T/D),ALT, alkaline phosphatase, GGT,albumin
dailyBaseline
2-3x/weekweekly
Triglycerides When lipid infusion reaches 1.5 gfat/kg/d and3 g fat/kg/d
weekly
CBC/Diff and platelets weekly
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Laboratory monitoring of infants receiving parenteral nutrition (PN)
Laboratory test Frequency
Blood
Electrolytes: sodium, potassium, chloride, bicarbonate
Daily till stable, then serially as indicated
Glucose Daily till stable, then serially as indicated
BUN, creatinine, calcium, phosphorus, magnesium, alkaline phosphatase, liver function studies (bilirubin, alanine and aspartate aminotransferases)
After the first week and then serially on a alternate week schedule as indicated
Urine dipstick Daily till stable then as indicated
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MONITORING GROWTH Weekly measurements of head circumference. Measurements
(weight, length and headcircumference) should be plotted on standard post-natal growth charts.
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Risks of PN
Line associated sepsis
Line related complications (eg thrombosis)
Hyperammonaemia
Hyperchloraemic acidosis
Cholestatic jaundice
Trace element deficiency
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TPN WEANING GUIDELINES guidelines may be used for both the preterm and term infant, although the term
infant may not need the concentrated breast milk/formula
When the patient is tolerating >50 ml/kg/day of feedings, the TPN should be gradually tapered off
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TPN WEANING GUIDELINES
maintains a minimum calorie intake of 100 kcal/kg/day and >2 grams
protein/kg/day.
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Table 5. TPN Weaning Guidelines:
Feed
Volume
(cc/kg)
PN Substrate
(CHO/prot/f
at)1
IV+po
Volume
(cc/kg)
Total TPN
Volume
(cc/kg)2,3
Ca/P
(mEq/
mmol)5
MBM/formula
concentration
(kcal/oz)
0-49 12/3.5/3 100-140 100-140 3/1.5 20
50-74 10/2.5/2 120-140 70-90 2.45/1.2 20
75-99 8/2/1.5 130-140 55-654 1.75/0.85 20
100-120 8/2/1 130-150 554 1.75/0.85 22
120-150 None NA None N/A 22-24
150-160 None NA None N/A 241. mg CHO/kg/min, g prot/kg, g fat/kg2. Total TPN volume= (IV+po goal)-(lower end of indicated feed volume
range)3. Total TPN volume includes lipids4. Keep the minimum dextrose/amino acid volume at 50 cc/kg for ordering
purposes5. Amount per kg as ordered on the TPN form
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DISCONTINUING PARENTERAL NUTRITIONinfant is tolerating >100-120 cc/kg of enteral feedings or is
receiving <25 cc/kg/d of PN.
The rate of dextrose administration should be tapered to prevent
rebound hypoglycemia.
Chemstrips should be done q6h.
Newborns need a slower tapering than older children
and require continued monitoring of glucose after the solution has been
stopped.
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DISCONTINUING PARENTERAL NUTRITIONLipids may be stopped without tapering.
If the PN catheter clots or infiltrates, start another IV
with dextrose concentration <12.5% depending on the current
glucose concentration.
The"Starter TPN" (D10W,AA3.5) may also be used to
maintain protein intake until a new bag arrives.
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Transitional Feeds
Reduce IV lipid by 50% when infant tolerates
100ml/kg/day of enteral feed.
Cease lipids when infant tolerates 120ml/kg/day
of enteral feeds
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