Neonatal Parenteral Nutrition: Basics for the NICU

Sharon Groh-Wargo, PhD, RD, LDNeonatal Nutritionist, MetroHealth Medical Center and Assistant Professor, Departments of Pediatrics and Nutrition, Case Western Reserve University School of Medicine

Objectives: After completing this module the resident will be able to…

Define parenteral nutrition and who needs itOrder appropriate NICU parenteral nutrition solutions Evaluate how well a parenteral nutrition regimen meets the needs of specific patients in the NICU

What is Parenteral Nutrition: Terminology

PN: Parenteral Nutrition – intravenous nutritional supportTPN: Total Parenteral Nutrition – parenteral nutrition supplying all known essential nutrients intravenously (patient is NPO)PPN: Partial Parenteral Nutrition – parenteral nutrition supplementing oral nutritionHyperalimentation (“hyperal”) – a vague, commonly used term meaning either partial or total parenteral nutrition

What is Parenteral Nutrition: ContentMacronutrients

Carbohydrate: dextrose monohydrateProtein: crystalline amino acidsFat: intravenous fat emulsion (ex Intralipid)

MicronutrientsVitamins – 4 fat soluble and 9 water soluble vitaminsMacrominerals – calcium, phosphorus and magnesiumElectrolytes – sodium, potassium, chlorideTrace elements – most commonly zinc, copper, chromium and manganese; less commonly selenium and iron; rarely molybdenum and iodine

Miscellaneous constituentsHeparin – to protect line integrity – 1 unit/mlCarnitine – to aid in fat metabolism – 10 mg/kgFamotidine – to protect the stomach mucosal surface area

Who Needs TPN or PPN?Patients who

Cannot eatWill not eatShould not eatCannot eat enough

Prematurity is related to many of the above and is the most common reason for PN in the NICUThe NICU generally has more patients on PN than the entire rest of the hospital combined

Initiation: Goal is by 24 hours of lifeThe initial PN solution may be just dextrose, and/or amino acids, and/or electrolytes, and/or calcium gluconateWithin the first 48 hours the parenteral nutrition solution should contain dextrose, amino acids, vitamins, electrolytes, macrominerals (Ca, P, Mg) and trace elementsIntravenous fat emulsion can be ordered as soon as the amino acid/dextrose solution but no later than 7 days of life

MaintenanceStandard solutions found on the TPN order form ordered at usual fluid volumes (100-150 ml/kg/d) and in conjunction with intravenous fat emulsions at a dose between 0.5-3 g/kg/dprovide balanced and appropriate nutrition for most NICU patientsPatients who deserve individualized TPN orders may include those with fluid restrictions, increased fluid requirements or unusual medical/surgical diagoses

ComplicationsGlucose/Electrolyte ImbalanceInfectionCholestasis:

TPN longer than two weeks increases riskdirect bilirubin >1.5mg% is diagnostic

Osteopenia: Risk factors: prematurity (low mineral stores), diuretics (increased mineral losses), TPN (solutions can’t contain sufficient mineral without precipitating)High alkaline phosphotase (>600U/l) and/or low serum phosphorus (<5 mg%)

MetroHealth ‘TPN’

Order Form: Front (left side of slide); Back (right side)

Step by Step TPN orderingThe following slides will show you highlighted sections of the TPN form and take you step by step through the ordering processThe first slide of each step will show you the section of the form to be discussedThe front of the form is where the actual order is indicated; the back of the form has explanatory information and details about vitamin and mineral content

Step 1: Order Volume and Lipid Dose

Step 1 (Continued)Order daily for exact volume (ml) needed Take to NICU desk to be faxed by 1PMDosing weight is defined on the back of the formLipid doses range from 0.5-3 g/kg; infusion time is described on the back of the form

Step 1 (Continued)

Information from the back of the TPN order form is shown on the left side of this slideTop left defines dosing weightBottom left describes lipid infusion time

Step 2: Choose a Base Solution

Step 2 (Continued)Start with Solution I (D10%AminoAcid1.5%)and progress as soon as possible to Solution II (D12%AA2%)Solutions III and IV (D15-20%; AA2.5-3%) require a central lineOrder ‘tailored solution’when a special glucose or AA% is requiredOrder ‘Neonatal AA’ for NICU patients

Step 2 (Continued)The box on the back of the form at the bottom has general informationChoosing ‘Neonatal AA’on the front of the form fills the TPN order with a pediatric solution containing a mix of essential and non-essential amino acids more appropriate for young infants

Step 3: Order Electrolytes & Minerals

Step 3 (Continued)

Usual ranges are listed; Na & K commonly adjustedAdjust mEq/kg of Na & K as fluid from TPN changesAdjust chloride % based on acid base balanceChoose “NICU guidelines” for Ca & P unless told to change; inappropriate adjustments may precipitate

Step 3 (Continued)

The table (above) is from the back of the order formCa and P guidelines are based on (1) day of life, (2) dosing weight, and (3) fluid volume in ml/kgInfants who are over 7 days and on full volume TPN receive 3 mEq/kg Ca & 1.5 mmol/kg P1 mEq calcium = 217 mg calcium gluconate

Step 4: Order Additional Additives

Step 4 (Continued)

Vitamins and heparin per guidelines are automaticTrace elements per guidelines unless cholestaticOrder Famotidine, Se and Carnitine as directedUse extra lines for iron dextran (1 mg/kg) with erythropoietin therapy or for other special orders

Step 4: ContinuedVitamins (left top) & trace elements (left bottom) from the back of the TPN order formDose of daily vitamins is based on weightAt low solution volume, vitamins may increase osmolality; pharmacy may call to ask your permission to delete them – instead ask that the vitamins be halved

Step 5: Signatures; Final Information

Print and sign your name; include Pin# and Beeper# (see left side of slide above)Recommended laboratory monitoring is on the back of the form (see right side of slide above)Check direct bilirubin after 2 weeks of TPN

TPN Daily Calculations: Ordering and Assessing Adequacy

Fluid (from all IV lines including medications): ml/kgEnergy (from glucose, amino acids and intravenous fat): kcal/kgCarbohydrate (glucose load): mg/kg/minuteProtein (from amino acid solution): grams/kgFat (from intravenous fat emulsion): g/kgElectrolytes: Na and K as mEq/kg

Fluid (ml/kg)Ordering

Calculate daily fluid allowance by multiplying goal ml/kg X weight (kg)Subtract fluids coming from all dextrose & normal saline IVs, intravenous fat, and enteral feedingsDivide remaining fluid by 24 to calculate parenteral nutrition IV rate ml/hourOrder Base Solution or tailored solution

Assessing IntakeAdd fluids from all IV and oral sources and divide by the kg weightInitial fluids are ~80 ml/kgPhototherapy increases fluid needsMaintenance fluids are about 150 ml/kgFluids should be adjusted and individualized often based on laboratory assessment and clinical condition

Energy (kcal/kg)D10%AA1.5% (0.4 kcal/ml)D12%AA2% (0.488 kcal/ml)D15%AA2.5% (0.61 kcal/ml)D20%AA3% (0.8 kcal/ml)Dextrose 3.4 kcal/g and protein 4 kcal/gIntravenous fat emulsion 20% (2 kcal/ml)Initial goal (weight neutral): 50-60 kcal/kgGoal (weight gain): 80-100 kcal/kg

Glucose Load (mg/kg/minute)Accounts for both infusion rate and %glucoseEspecially mportant to monitor in the first week of life in infants <1kg at birthCalculation:

ml/kg X % dextrose = g/kg glucose per dayg/kg X 1000 mg/g = mg/kg glucose per daymg/kg X 1440 minutes/day = mg/kg/minute

Initial glucose load is 5-8 mg/kg/minuteIncrease/decrease ~2mg/kg/minute based on serum glucose

Protein (g/kg)

Fluid volume (ml) X % amino acid = g protein (ex: 100 ml X .02 = 2 g protein)Minimum protein: 1g/kg (replaces daily urinary losses)Protein balance (initial goal): 1-2.5 g/kgPositive protein balance: 2.5-3.5 g/kg (for growth)

Fat (g/kg)

Start with dose of 0.5-1 g/kgMultiply g/kg X 2.5 to derive volume Use volume to calculate calories (2 kcal/ml)Increase by 0.5-1 g/kg per day using the smaller dose increase for the smaller babiesReduce or stop lipids if sepsis occurs0.5-1 g/kg meets essential fatty acids needs>1g/kg provides energy

Electrolytes (mEq/kg)Start with suggested pediatric ranges unless instructed otherwiseMonitor laboratory values closely especially in young and very small babies; adjust accordingAdjust Na and K as volume from TPN decreases and oral feedings increase (for example, an infant receiving 5 mEq/kg Na per day when on 150 ml/kg TPN does not usually need 5 mEq/kg Na coming from the parenteral nutrition solution when it provides only 50 ml/kg

SummaryPrematurity is a common reason for PNPN is ordered daily in the NICUPN ordered using standard solutions at usual volumes and with NICU guidelines can provide adequate amounts of all KNOWN essential nutrientsDaily calculations for each patient should include volume (ml/kg), energy (kcal/kg), protein (g/kg), fat (g/kg) and electrolytes (mEq/kg); glucose load (mg/kg/minute) should be calculated in young, ELBW infants

ReferencesShulman RJ and Phillips S. 2003. Invited Review: Parenteral Nutrition in Infants and Children. Journal of Pediatric Gastroenterology and Nutrition 36: 587-607.Koletzko B, Goulet O, Hunt J, Krohn K, Shamir R, for the Parenteral Nutrition Guidelines Working Group. 2005. Guidelines on Paediatric Parenteral Nutrition. Journal of Pediatric Gastroenterology and Nutrition

Questions

(1) Describe the parenteral solutions you would prescribe for a two day old 680g infant including the hourly rate of the infusion.

Questions

(2) For an 820g infant on Dextrose 12% Amino Acid 2% at 5 ml/hr and intravenous fat emulsion at 4.1 ml per day calculate:

ml/kg, kcal/kg, g protein/kg, and g fat/kgWhat is your assessment of the above

Questions (continued)

(3) A 4 day old 510g infant is receiving 200ml/kg ‘D12 hyperal’ and now has a blood sugar >200mg%. What is your assessment and how would you treat?

Questions (continued)(4) On the first day of service you pick up a former VLBW infant now 4 weeks, 1550g on the following PPN regimen:

D12%AminoAcid2% at 1.9 ml/hr; Na 6mEq/kg, K 3 mEq/kg, Mg 0.5 mEq/kg and NICU guidelines for Ca, P, vitamins and trace elementsLipids at 1 g/kg over 18 hoursSimilac Special Care 24 with iron 23 ml q 3 hrsWhat is your assessment?

Date Written

April 7, 2006