Parenteral Parenteral NutritionNutritionMargel Camille Luy-GalagarMargel Camille Luy-Galagar

ParenteralParenteral nutrition nutrition is administered outside the is administered outside the digestive tract, intravenously. This is in contrast to digestive tract, intravenously. This is in contrast to enteralenteral nutrition nutrition, which encompasses oral and , which encompasses oral and tube feedings into the digestive tract.tube feedings into the digestive tract.

The general rule of thumb for deciding whether to The general rule of thumb for deciding whether to use parenteral or enteral feeding, is "if the gut use parenteral or enteral feeding, is "if the gut works, use it". The GI tract should be used if works, use it". The GI tract should be used if possible because it tends to possible because it tends to atrophyatrophy when not when not used. Gut bacteria can translocate to the used. Gut bacteria can translocate to the circulatory system through an atrophied GI tract circulatory system through an atrophied GI tract and increase the risk of infection.and increase the risk of infection.

Peripheral Parenteral Peripheral Parenteral Nutrition Nutrition

With peripheral parenteral nutrition (PPN) With peripheral parenteral nutrition (PPN) nutrients are supplied via a peripheral nutrients are supplied via a peripheral vein, usually a vein in the arm. Another vein, usually a vein in the arm. Another term for PPN is peripheral venous term for PPN is peripheral venous nutrition (PVN) nutrition (PVN)

Hypertonic Solutions Hypertonic Solutions Peripheral parenteral nutrition feedings usually Peripheral parenteral nutrition feedings usually

supplement enteral feedings. Large amounts of supplement enteral feedings. Large amounts of nutrients cannot be supplied via a peripheral nutrients cannot be supplied via a peripheral vein, because these relatively small veins vein, because these relatively small veins cannot tolerate the rush of fluid into the vein cannot tolerate the rush of fluid into the vein that occurs when a hypertonic solution is that occurs when a hypertonic solution is introduced into the circulatory system.introduced into the circulatory system.

Body fluids have an osmolarity of about 300 Body fluids have an osmolarity of about 300 mOsm. The introduction of a hypertonic mOsm. The introduction of a hypertonic solution into a body compartment will cause an solution into a body compartment will cause an osmotic gradient, resulting in a fluid shift.osmotic gradient, resulting in a fluid shift.

Hypertonic-Hypertonic- having a higher osmolality having a higher osmolality than the comparison solution. than the comparison solution.

osmotic gradient-osmotic gradient- solutions on either side solutions on either side of a semipermeable membrane. of a semipermeable membrane.

Osmolarity- Osmolarity- The osmolarity of a PPN The osmolarity of a PPN solution is an important consideration in solution is an important consideration in PN solutions. Osmolarity is the number of PN solutions. Osmolarity is the number of dissolved molecules and ions per liter of a dissolved molecules and ions per liter of a solution.solution.

It may be easier to think of osmolarity as the It may be easier to think of osmolarity as the number of particles per liter of water. number of particles per liter of water.

Hypertonic Solutions Hypertonic Solutions When a hypertonic solution is introduced into a When a hypertonic solution is introduced into a

small vein with a low blood flow, fluid from the small vein with a low blood flow, fluid from the surrounding tissue moves into the vein due to surrounding tissue moves into the vein due to osmosis. The area can become inflamed, and osmosis. The area can become inflamed, and thrombosis can occur.thrombosis can occur.

A hypertonic PN solution results in an osmotic A hypertonic PN solution results in an osmotic gradient that causes water to enter the blood gradient that causes water to enter the blood vessel, as is illustrated in the picture, where vessel, as is illustrated in the picture, where high concentrations of glucose (green) and high concentrations of glucose (green) and amino acids (yellow) draw water (blue) into a amino acids (yellow) draw water (blue) into a blood vessel (red). blood vessel (red).

Osmolarity of Solutions Osmolarity of Solutions

Protein and carbohydrate both contribute Protein and carbohydrate both contribute to hypertonicity. Fat is isotonic, and can to hypertonicity. Fat is isotonic, and can therefore be administered peripherally. therefore be administered peripherally. However, if the patient has delayed lipid However, if the patient has delayed lipid clearance, the use of lipids is clearance, the use of lipids is contraindicated. contraindicated.

Infusion of Peripheral Infusion of Peripheral Nutrition Nutrition

In peripheral PN, the catheter is inserted In peripheral PN, the catheter is inserted into the arm vein of the patient. Up to into the arm vein of the patient. Up to 1800-2500 kcal and 90g protein can be 1800-2500 kcal and 90g protein can be supplied via peripheral parenteral supplied via peripheral parenteral nutrition. However, this relatively high nutrition. However, this relatively high kcalorie/protein amount can be supported kcalorie/protein amount can be supported peripherally only for a short period of peripherally only for a short period of time. time.

Recommended Rates Recommended Rates

IBWIBW Infusion rate (cc/hr)Infusion rate (cc/hr)

4040 60-8060-80

5050 75-10075-100

7070 100-140100-140

8080 120-160120-160

9090 130-170130-170

Total Parenteral Nutrition Total Parenteral Nutrition

Total parenteral nutrition (TPN) is Total parenteral nutrition (TPN) is sometimes called central parenteral sometimes called central parenteral nutrition (CPN) or "hyperal" nutrition (CPN) or "hyperal" (hyperalimentation).(hyperalimentation).

Hypertonic Solutions Hypertonic Solutions Large amounts of nutrients in a hypertonic Large amounts of nutrients in a hypertonic

solution can be supplied via TPN. The catheter solution can be supplied via TPN. The catheter is surgically placed into the superior vena cava.is surgically placed into the superior vena cava.

The reason that larger amounts of nutrients in The reason that larger amounts of nutrients in a hypertonic solution can be supplied via the a hypertonic solution can be supplied via the superior vena cava than with peripheral superior vena cava than with peripheral parenteral nutrition is that the superior vena parenteral nutrition is that the superior vena cava has a much larger diameter and a higher cava has a much larger diameter and a higher blood flow rate, both of which serve to quickly blood flow rate, both of which serve to quickly dilute the TPN solution. dilute the TPN solution.

Amino Acid Solutions Amino Acid Solutions

Protein is provided as a crystalline amino acid Protein is provided as a crystalline amino acid solution. 500 ml bottles are standard.solution. 500 ml bottles are standard.

Solutions vary in amino acid concentration and Solutions vary in amino acid concentration and amino acid composition. The patient's protein amino acid composition. The patient's protein needs determine the protein concentration to needs determine the protein concentration to use, and the underlying disease state use, and the underlying disease state determines the composition of amino acids to determines the composition of amino acids to use.use.

Amino acid (AA) Amino acid (AA) solutions are solutions are generally available in generally available in the following the following concentrations: concentrations:

% solution% solution AA contentAA content

(g/100ml)(g/100ml)

3.0%3.0% 3.03.0

3.5%3.5% 3.53.5

5.0%5.0% 5.05.0

7.0%7.0% 7.07.0

8.5%8.5% 8.58.5

10.0%10.0% 10.010.0

Uses of Amino Acids Uses of Amino Acids

Although amino acids have 4 kcalories Although amino acids have 4 kcalories per gram, they do not normally contribute per gram, they do not normally contribute to the kcalorie requirement of the patient. to the kcalorie requirement of the patient. Instead of being used for energy, amino Instead of being used for energy, amino acids should be used for protein acids should be used for protein synthesis. Typically, to determine protein synthesis. Typically, to determine protein needs, a nonprotein kcalorie to nitrogen needs, a nonprotein kcalorie to nitrogen ratio of 80:1 to 150:1 is used. ratio of 80:1 to 150:1 is used.

Nonprotein kcal:N ratio Nonprotein kcal:N ratio 80:180:1 the most severely stressed the most severely stressed

patientspatients 100:1100:1 severely stressed patientsseverely stressed patients 150:1150:1 unstressed patientunstressed patient

Dextrose Solutions Dextrose Solutions

Dextrose in solution has 3.4 kcalories per Dextrose in solution has 3.4 kcalories per gram rather than 4 kcalories per gram as gram rather than 4 kcalories per gram as in dietary carbohydrates, because a in dietary carbohydrates, because a noncaloric water molecule is attached to noncaloric water molecule is attached to dextrose molecules. Dextrose solutions dextrose molecules. Dextrose solutions come in different concentrations, and the come in different concentrations, and the solution is abbreviated D(%solution)W. solution is abbreviated D(%solution)W. For example, D50W indicates a 50% For example, D50W indicates a 50% dextrose in water solution.dextrose in water solution.

Infusion Rate of Dextrose Infusion Rate of Dextrose

Dextrose solutions should not be administered Dextrose solutions should not be administered at a rate higher than 0.36g per kg body at a rate higher than 0.36g per kg body weight/hour. This is the maximum oxidation weight/hour. This is the maximum oxidation rate of glucose. Excess glucose is converted to rate of glucose. Excess glucose is converted to fat, which can result in fatty liver. In addition, fat, which can result in fatty liver. In addition, the conversion of carbohydrate to fat can the conversion of carbohydrate to fat can cause excess CO2 production, which is cause excess CO2 production, which is undesirable for patients with respiratory undesirable for patients with respiratory problems. problems.

Example maximum dextrose calculationExample maximum dextrose calculation

60 kg patient: 60 kg patient:

Dextrose infusion should not be greater Dextrose infusion should not be greater than .36g/kg/hrthan .36g/kg/hr

0.36 x 60 kg x 24 hr0.36 x 60 kg x 24 hr= 518 grams per day = 518 grams per day

Practice Calculation:Practice Calculation:

70 kg=_______g70 kg=_______g

80 kg=_______g80 kg=_______g

90 kg=_______g90 kg=_______g

100 kg=______g100 kg=______g

Lipid Emulsions Lipid Emulsions

Lipids in parenteral nutrition are used as Lipids in parenteral nutrition are used as a source of a source of essential fatty acids (EFA)essential fatty acids (EFA) and energy. Lipid emulsions are and energy. Lipid emulsions are composed of soybean and/or safflower composed of soybean and/or safflower oil, glycerol, and egg phospholipid.oil, glycerol, and egg phospholipid.

Approximately 4% of total kcaloric intake Approximately 4% of total kcaloric intake should be EFAs to prevent EFA should be EFAs to prevent EFA deficiency.deficiency.

Since IV lipids are isotonic and calorically Since IV lipids are isotonic and calorically dense, they are a good source of dense, they are a good source of kcalories for hypermetabolic patients, or kcalories for hypermetabolic patients, or patients with volume or carbohydrate patients with volume or carbohydrate restrictions. Lipids can provide up to 60% restrictions. Lipids can provide up to 60% of non-protein calories. of non-protein calories.

Essential Fatty Acids Essential Fatty Acids

Before lipids could be administered Before lipids could be administered intravenously, essential fatty acids were intravenously, essential fatty acids were provided by rubbing vegetable oil into the provided by rubbing vegetable oil into the patient's skin. Today, however, the patient's skin. Today, however, the efficacy of this procedure is controversial, efficacy of this procedure is controversial, but it might be used in the case of but it might be used in the case of patients who cannot tolerate a lipid patients who cannot tolerate a lipid emulsion. emulsion.

Lipid Emulsion Lipid Emulsion Concentrations Concentrations

IV lipids come in bottles of 10% or 20% IV lipids come in bottles of 10% or 20% emulsions. The 10%emulsions. The 10%emulsion contains 1.1 kcal/ml the 20% emulsion contains 1.1 kcal/ml the 20% emulsion contains 2 kcal/ml.emulsion contains 2 kcal/ml.

Bottles come in the following volumes - Bottles come in the following volumes - 100 ml, 200 ml, 250 ml or 500 ml.100 ml, 200 ml, 250 ml or 500 ml.

500 ml of 10% lipids given once or twice 500 ml of 10% lipids given once or twice a week is generally enough to prevent a week is generally enough to prevent essential fatty acid deficiency.essential fatty acid deficiency.

The lipid emulsion does not have to be The lipid emulsion does not have to be mixed with the amino acid and dextrose mixed with the amino acid and dextrose solutions in a single bag.solutions in a single bag.

Lipid Emulsion Lipid Emulsion Administration Administration

To prevent hyperlipidemia, lipid emulsions are To prevent hyperlipidemia, lipid emulsions are not provided continuously. This gives the body not provided continuously. This gives the body a chance to clear lipids from the blood. a chance to clear lipids from the blood. Typically, lipids are administered 2-3 times per Typically, lipids are administered 2-3 times per week, but can be provided daily. Infusion times week, but can be provided daily. Infusion times of 4-6 hours for 10% lipids and 8-12 hours for of 4-6 hours for 10% lipids and 8-12 hours for 20% lipids are recommended, although 12-24 20% lipids are recommended, although 12-24 hour infusions may be better tolerated by some hour infusions may be better tolerated by some patients. patients.

In any event, a total of 2.5g/kg lipids per In any event, a total of 2.5g/kg lipids per day should not be exceeded. day should not be exceeded.

Example calculation of maximum daily Example calculation of maximum daily lipidslipids

60 kg patient 60 kg patient

2.5g/kg x 60 kg2.5g/kg x 60 kg= 150g lipid per day maximum = 150g lipid per day maximum

Practice for 70-100 kgPractice for 70-100 kg

Evaluation of Lipid Evaluation of Lipid Tolerance Tolerance

There are three methods that can be There are three methods that can be used for evaluation of a patient's lipid used for evaluation of a patient's lipid tolerance: tolerance: Test doseTest dose Serum triglyceridesSerum triglycerides Plasma TurbidityPlasma Turbidity

Test Dose Method Test Dose Method

10% lipid infused @ 1ml/min for 15-30 10% lipid infused @ 1ml/min for 15-30 min; if no adverse symptoms, the rate min; if no adverse symptoms, the rate can be increase to 80 - 100 ml/hcan be increase to 80 - 100 ml/h

oror 20% lipid emulsion infused @ .5 ml/min 20% lipid emulsion infused @ .5 ml/min

for 15 - 30 min; if no adverse symptoms, for 15 - 30 min; if no adverse symptoms, the rate can be increase to 40 - 50 ml/hthe rate can be increase to 40 - 50 ml/h

Serum Triglyceride Serum Triglyceride Method Method

Determine a baseline serum triglyceride level Determine a baseline serum triglyceride level before the emulsion is administered. before the emulsion is administered.

Determine the triglyceride level 8 hours after Determine the triglyceride level 8 hours after the infusion has been terminated. the infusion has been terminated.

If serum triglycerides are normal or if they If serum triglycerides are normal or if they exceed 250 mg/day, lipids should be given at exceed 250 mg/day, lipids should be given at a reduced rate or should be used only to a reduced rate or should be used only to prevent essential fatty acid deficiency. prevent essential fatty acid deficiency.

Plasma Turbidity Method Plasma Turbidity Method

Plasma is observed for turbidity, and if Plasma is observed for turbidity, and if turbidity is present, the lipid infusion must turbidity is present, the lipid infusion must be adjusted. This is not the best method be adjusted. This is not the best method for testing lipid tolerance, because for testing lipid tolerance, because hyperlipidemia can occur without hyperlipidemia can occur without turbidity. turbidity.

Contraindications for Contraindications for Lipid EmulsionsLipid Emulsions

Contraindications for using lipid Contraindications for using lipid emulstion include:emulstion include: Abnormal lipid metabolism Abnormal lipid metabolism Lipid nephrosisLipid nephrosis Acute pancreatitis (if concomitant with or Acute pancreatitis (if concomitant with or

caused by hyperlipidemia) caused by hyperlipidemia) Severe egg allergies Severe egg allergies

Use lipid emulsions with caution if the patient Use lipid emulsions with caution if the patient has:has: A blood coagulation disorder A blood coagulation disorder Moderate to severe liver disease Moderate to severe liver disease Compromised pulmonary function Compromised pulmonary function

For patients who do not tolerate lipid For patients who do not tolerate lipid emulsions, meeting essential fatty acid needs emulsions, meeting essential fatty acid needs can be difficult. Rubbing vegetable oil on the can be difficult. Rubbing vegetable oil on the patient's skin may provide some essential fatty patient's skin may provide some essential fatty acids, but the efficacy is controversial. acids, but the efficacy is controversial.

Administration of Lipids Administration of Lipids

Traditionally, lipids are administered in a Traditionally, lipids are administered in a bottle that is Y-connected, or bottle that is Y-connected, or piggybacked to the IV line containing piggybacked to the IV line containing amino acid/dextrose mixture.amino acid/dextrose mixture.

Total nutrient admixtures (TNAs) also Total nutrient admixtures (TNAs) also called 3 in 1 systems, allow for lipids to called 3 in 1 systems, allow for lipids to be administered with amino acids and be administered with amino acids and dextrose. dextrose.

Minerals and Electrolytes Minerals and Electrolytes

Standard mineral and electrolyte Standard mineral and electrolyte mixtures are available, and are designed mixtures are available, and are designed to meet the normal range of daily to meet the normal range of daily mineral/electrolyte requirements. mineral/electrolyte requirements. Individual electrolyte levels can be Individual electrolyte levels can be altered to meet the needs of patients.altered to meet the needs of patients.

Mineral supplementation can be Mineral supplementation can be calculated based on health status or calculated based on health status or laboratory values.laboratory values.

Trace Elements Trace Elements

Standard Standard trace elementtrace element mixtures are available, mixtures are available, but requirements should be monitored and but requirements should be monitored and adjusted based on serum concentrations. adjusted based on serum concentrations.

Iron can be given intramuscularly as needed. Iron can be given intramuscularly as needed. When When transferrintransferrin levels are low, free iron levels are low, free iron increases and can increase susceptibility to increases and can increase susceptibility to infections. In addition, critically ill or infections. In addition, critically ill or malnourished patients often have no bone malnourished patients often have no bone marrow response to iron. marrow response to iron.

Copper supplementation must be Copper supplementation must be administered with caution to avoid administered with caution to avoid toxicity. Extra zinc may be needed by toxicity. Extra zinc may be needed by some patients to promote wound healing. some patients to promote wound healing.

Trace ElementTrace ElementSupplementation Supplementation

ElementElement DoseDose

Zinc Zinc 2.5 - 4.0mg2.5 - 4.0mg

Copper Copper 0.5 - 1.5 mg0.5 - 1.5 mg

IronIron 1.0 mg1.0 mg

ChromiumChromium 10 - 15 mcg10 - 15 mcg

ManganeseManganese 0.15 - 1.8 mg0.15 - 1.8 mg

IodineIodine 1 - 2 mcg1 - 2 mcg

SeleniumSelenium 20 - 40 mcg20 - 40 mcg

Vitamins Vitamins

Commercial vitamin preparations for TPN are Commercial vitamin preparations for TPN are available. The vitamin requirements for TPN available. The vitamin requirements for TPN patients are different from non-TPN patients patients are different from non-TPN patients because absorption is not a factor with TPN. because absorption is not a factor with TPN.

When needs are increased for certain disease When needs are increased for certain disease states, single vitamin supplements can be states, single vitamin supplements can be added to the solution. Serum vitamin levels can added to the solution. Serum vitamin levels can be monitored and dosage adjusted be monitored and dosage adjusted accordingly. accordingly.

Vitamin preparations should be added to Vitamin preparations should be added to the TPN solution just prior to the TPN solution just prior to administration to avoid losses from light administration to avoid losses from light exposure. exposure.

Water/Fat Soluble Water/Fat Soluble Vitamins Vitamins

Water soluble vitamins are provided at Water soluble vitamins are provided at levels greater than the RDA since rapid levels greater than the RDA since rapid administration exceeds renal threshold administration exceeds renal threshold and therefore increases urinary losses. and therefore increases urinary losses.

Fat soluble vitamins can become toxic, Fat soluble vitamins can become toxic, and are provided in amounts equal to the and are provided in amounts equal to the RDA, except for Vitamin K. RDA, except for Vitamin K.

Vitamin K is not provided because it may Vitamin K is not provided because it may interfere with anticoagulant medications. interfere with anticoagulant medications. Vitamin K must be given parenterally or Vitamin K must be given parenterally or intramuscularly, at a dose of 2-4 mg/wk, intramuscularly, at a dose of 2-4 mg/wk, depending on prothrombin time. A long depending on prothrombin time. A long prothrombin time indicates an increased prothrombin time indicates an increased vitamin K need. vitamin K need.

Other Components of Other Components of PN Solutions PN Solutions

Other components commonly added to Other components commonly added to parenteral solutions include:parenteral solutions include:

AlbuminAlbumin Can be added if serum albumin levels are very low. Can be added if serum albumin levels are very low.

HeparinHeparin An anticoagulant used to prevent blood clots from An anticoagulant used to prevent blood clots from

forming on the IV catheter. forming on the IV catheter.

InsulinInsulin Used if needed to regulate blood glucose levels.Used if needed to regulate blood glucose levels.

Ordering and Mixing PN Ordering and Mixing PN Solutions Solutions

The physician writes the order for the TPN The physician writes the order for the TPN prescription. Often a form is used.prescription. Often a form is used.

The pharmacist mixes the TPN solution using The pharmacist mixes the TPN solution using aseptic technique. Prescriptions are aseptic technique. Prescriptions are compounded by mixing the solutions at a 1:1 compounded by mixing the solutions at a 1:1 dextrose-to-amino acid ratio and placing in 1-L dextrose-to-amino acid ratio and placing in 1-L bags. Alternatively, lipids can be mixed with the bags. Alternatively, lipids can be mixed with the dextrose/amino acid solution, referred to as the dextrose/amino acid solution, referred to as the 3-in-1 total nutrient admixture (TNA).3-in-1 total nutrient admixture (TNA).

Calculation of protein Calculation of protein needs:needs:

Protein requirements vary with the Protein requirements vary with the patient's disease state. Protein needs patient's disease state. Protein needs can be estimated by multiplying can be estimated by multiplying kilograms of body weight by a factor, or kilograms of body weight by a factor, or by making a nitrogen balance study. by making a nitrogen balance study.

Gram/kg Method for Gram/kg Method for Determining Protein NeedsDetermining Protein Needs

The simplest, but least precise, method The simplest, but least precise, method to estimate protein needs is by to estimate protein needs is by multiplying IBW in kilograms by a factor multiplying IBW in kilograms by a factor appropriate for the patient's condition. appropriate for the patient's condition.

If this method is used, the patient must If this method is used, the patient must be monitored for protein status to be monitored for protein status to determine if adjustment in the protein determine if adjustment in the protein prescription is necessary.prescription is necessary.

Example Gram/kg Calculation Example Gram/kg Calculation

IBW: 120lb; 54.5 kg (120/2.2)IBW: 120lb; 54.5 kg (120/2.2)

Moderate stress (factor = 1.5 from chart) Moderate stress (factor = 1.5 from chart) 54.5 kg x 1.5 g/kg = 81.75 (82) grams of 54.5 kg x 1.5 g/kg = 81.75 (82) grams of protein/dayprotein/day

Practice:Practice:

1.1. Adult non-stressed; IBW= 60 kgAdult non-stressed; IBW= 60 kg

2.2. Adult moderately stressed; IBW= 70 kgAdult moderately stressed; IBW= 70 kg

3.3. Non- stressed; 2 y/o; IBW= 12 kgNon- stressed; 2 y/o; IBW= 12 kg

Calculation of Energy Calculation of Energy NeedsNeeds

Energy needs of the hospitalized Energy needs of the hospitalized patient can be determined by several patient can be determined by several methods. methods.

1. = 1. = Basal Energy ExpenditureBasal Energy Expenditure x activity x activity factor x stress factor. factor x stress factor.

2. Kcals per kilogram body weight 2. Kcals per kilogram body weight according to weight and activity according to weight and activity classification. classification.

Keep in mind that individual needs vary. Keep in mind that individual needs vary. Each of these methods provides a Each of these methods provides a ballpark value. Patients must be ballpark value. Patients must be monitored for weight status and the kcal monitored for weight status and the kcal prescription should be adjusted prescription should be adjusted accordingly. accordingly.

There are two main methods to ascertain There are two main methods to ascertain basal energy expenditure (BEE) - either basal energy expenditure (BEE) - either indirect calorimetry or via a prediction indirect calorimetry or via a prediction equation, the most common of which is equation, the most common of which is the Harris Benedict Equation (HBE). the Harris Benedict Equation (HBE).

Once BEE has been determined, that Once BEE has been determined, that figure is multiplied by an activity factor figure is multiplied by an activity factor (AF) then an injury factor (IF) to (AF) then an injury factor (IF) to determine the total energy needs of the determine the total energy needs of the patient. patient.

Activity factor =Activity factor = 1.2 if patient is confined to bed 1.2 if patient is confined to bed 1.3 if patient is ambulatory 1.3 if patient is ambulatory

The Harris-Benedict The Harris-Benedict Equation Equation

The Harris Beneditc Equation (HBE) is The Harris Beneditc Equation (HBE) is one of over 200 equations for estimating one of over 200 equations for estimating basal energy expenditure (BEE). The basal energy expenditure (BEE). The HBE is a regression equation taking into HBE is a regression equation taking into consideration gender, height, weight and consideration gender, height, weight and age. The HBE for men and women is as age. The HBE for men and women is as follows: follows:

MenMen BEE (kcal/d) = 66.5 + (13.8 x W) + (5.0 x H) BEE (kcal/d) = 66.5 + (13.8 x W) + (5.0 x H)

- (6.8 x A) - (6.8 x A)

WomenWomen BEE (kcal/d) = 655.1 + (9.1 x W) + (1.8 x H) BEE (kcal/d) = 655.1 + (9.1 x W) + (1.8 x H)

- (4.7 x A) - (4.7 x A)

Where W = weight in kg Where W = weight in kg and H = height in cm and H = height in cm

Example BEE Calculation Example BEE Calculation

Male; W=60 kg; H=150 cm; A=30 years Male; W=60 kg; H=150 cm; A=30 years

BEE (kcal/d) = 66.5 + (13.8 x 60) + (5.0 x BEE (kcal/d) = 66.5 + (13.8 x 60) + (5.0 x 150) - 6.8 x 30)150) - 6.8 x 30)

66.5 + 828 + 750 - 204 = 144066.5 + 828 + 750 - 204 = 1440

Practice:Practice:

1.1. Male; 70 kg; 170 cm; 60 y/o Male; 70 kg; 170 cm; 60 y/o

2.2. Female; 50 kg; 160 cm; 40 y/o Female; 50 kg; 160 cm; 40 y/o

3.3. Male; 80 kg; 180 cm; 35 y/o Male; 80 kg; 180 cm; 35 y/o

Example Energy Needs Example Energy Needs Calculation Calculation

Estimate energy needs (kcals) using Estimate energy needs (kcals) using

BEE x AF x IF BEE = 1000 kcalsBEE x AF x IF BEE = 1000 kcalsAF=1.2AF=1.2IF = 1.2IF = 1.2

Energy needs = 1000 x 1.2 x 1.2 = 1440 Energy needs = 1000 x 1.2 x 1.2 = 1440 kcal/daykcal/day

Practice:Practice:

1.1. BEE: 1200; AF: 1.2; IF: 1.5 BEE: 1200; AF: 1.2; IF: 1.5

2.2. BEE: 1300; AF: 1.3; IF: 1.3 BEE: 1300; AF: 1.3; IF: 1.3

3.3. BEE: 1500; AF: 1.3; IF: 1.4 BEE: 1500; AF: 1.3; IF: 1.4

4.4. BEE: 1600; AF: 1.2; IF: 2.0 BEE: 1600; AF: 1.2; IF: 2.0

Initial Considerations Initial Considerations

TPN infusion should start slowly so that the TPN infusion should start slowly so that the body has time to adapt to both the glucose body has time to adapt to both the glucose load and the hyperosmolarity of the solution, load and the hyperosmolarity of the solution, and to avoid fluid overload. and to avoid fluid overload.

A pump controls the infusion rate of the TPN A pump controls the infusion rate of the TPN solution.solution.

There are specific steps in the inititiation There are specific steps in the inititiation procedure to follow regarding the initiation of procedure to follow regarding the initiation of TPN infusion.TPN infusion.

General PN Initiation General PN Initiation Procedures Procedures

Start with 1 liter of TPN solution during the first Start with 1 liter of TPN solution during the first 24 hours (or use 42 cc/hr as a typical start rate) 24 hours (or use 42 cc/hr as a typical start rate)

Increase volume by 1 liter each day until the Increase volume by 1 liter each day until the desired volume is reacheddesired volume is reached

Monitor blood glucose and electrolytes closelyMonitor blood glucose and electrolytes closely Pump administer TPN at a steady ratePump administer TPN at a steady rate Don't attempt to catch up if administration Don't attempt to catch up if administration

gets behind.gets behind.

Continuous vs. Cyclic Continuous vs. Cyclic

With cyclic TPN, the patient is fed at With cyclic TPN, the patient is fed at nightnightso he or she can be free from the TPN so he or she can be free from the TPN pump during the daypump during the day

Typically, the TPN solution is infused at a Typically, the TPN solution is infused at a constant rate controlled by a pump. constant rate controlled by a pump. However, if the patient is to be nourished However, if the patient is to be nourished via TPN for an extended period of time, via TPN for an extended period of time, cyclic TPN is often used. cyclic TPN is often used.

With cyclic TPN the patient is fed for 12-With cyclic TPN the patient is fed for 12-18 hours during the night and fasts 18 hours during the night and fasts during the day. This gives the long-term during the day. This gives the long-term TPN patient freedom from the machinery TPN patient freedom from the machinery to lead a less restricted life during the to lead a less restricted life during the day. day.

Cyclic TPN helps prevent hepatotoxicity Cyclic TPN helps prevent hepatotoxicity that can develop with long-term TPN and that can develop with long-term TPN and the fasting period allows essential fatty the fasting period allows essential fatty acids to be released from fat stores. acids to be released from fat stores.

Monitoring Monitoring Considerations Considerations

The initial TPN prescription is based only The initial TPN prescription is based only on on estimatesestimates of the patient's kcalorie, of the patient's kcalorie, protein, and micronutrient needs. The protein, and micronutrient needs. The patient's weight, protein, and patient's weight, protein, and micronutrient status must be monitored to micronutrient status must be monitored to ensure the prescription's adequacy. ensure the prescription's adequacy.

Assessment considerations include:Assessment considerations include: Maximum weight gain in anabolism is 1/4 Maximum weight gain in anabolism is 1/4

to 1/2 pound per day. More than that to 1/2 pound per day. More than that indicates fluid retention. indicates fluid retention.

Adjust calcium lab values in Adjust calcium lab values in hypoalbuminemic patients as follows: hypoalbuminemic patients as follows: ionized CA = (measured serum CA) + ionized CA = (measured serum CA) + [4.0 - actual albumin (g/dL)] x 0.8 [4.0 - actual albumin (g/dL)] x 0.8

Terminating the Infusion Terminating the Infusion

The procedure for terminating the TPN The procedure for terminating the TPN infusion is controversial. Some patients infusion is controversial. Some patients can tolerate an abrupt stop, and others can tolerate an abrupt stop, and others tolerate a gradual termination, over a two tolerate a gradual termination, over a two hour period, better. hour period, better.

Rebound Hypoglycemia Rebound Hypoglycemia

Gradual termination prevents rebound Gradual termination prevents rebound hypoglycemia, especially for diabetic, septic, hypoglycemia, especially for diabetic, septic, and stressed patients. and stressed patients.

The endocrine system adjusts to a continuous The endocrine system adjusts to a continuous infusion of dextrose by secreting a certain level infusion of dextrose by secreting a certain level of insulin. If the dextrose supply is withdrawn of insulin. If the dextrose supply is withdrawn suddenly, the insulin level will not adjust right suddenly, the insulin level will not adjust right away, resulting in a relative insulin excess and away, resulting in a relative insulin excess and hypoglycemia. hypoglycemia.

   

Transitioning to Tube Transitioning to Tube Feeding Feeding

To ensure that the patient's nutrient needs To ensure that the patient's nutrient needs continue to be met, the TPN infusion should be continue to be met, the TPN infusion should be continued when the tube feeding begins..continued when the tube feeding begins..

If the gut hasn't been used for two or more If the gut hasn't been used for two or more weeks, enteral feeding tolerance may be weeks, enteral feeding tolerance may be compromised.compromised.

TPN infusion can be decreased in proportion TPN infusion can be decreased in proportion to the increase in tube feeding.to the increase in tube feeding.

Hints to Increae Enteral Hints to Increae Enteral Formula Tolerance Formula Tolerance

To enhance enteral formula tolerance To enhance enteral formula tolerance Start at slow rate (30 mL/hour) and/or with Start at slow rate (30 mL/hour) and/or with

half-strength formula half-strength formula Avoid hyperosmolar forumlas Avoid hyperosmolar forumlas Do not use bolus feedings Do not use bolus feedings Diluted Diluted hydrolyzed proteinhydrolyzed protein may stimulate may stimulate

gut hypertrophygut hypertrophy if formula isn't tolerated if formula isn't tolerated

Transitioning to Oral Transitioning to Oral Feeding Feeding

To ensure that the patient's nutrient To ensure that the patient's nutrient needs are met, TPN infusion should needs are met, TPN infusion should continue while oral feedings are initiated. continue while oral feedings are initiated.

Because the digestive tract can atrophy Because the digestive tract can atrophy if not used for more than two weeks, food if not used for more than two weeks, food may not be tolerated well at first. TPN may not be tolerated well at first. TPN should be continued until nutrient needs should be continued until nutrient needs are met with food.are met with food.

Hints to Increase Tolerance Hints to Increase Tolerance of Oral Feedings of Oral Feedings

To enhance enteral formula tolerance: To enhance enteral formula tolerance: If the patient is consuming an enteral formula If the patient is consuming an enteral formula

serve it diluted serve it diluted Have patient sip small volumes frequently at first Have patient sip small volumes frequently at first Gradually increae volumes and time between Gradually increae volumes and time between

feedings feedings If patient is to be weaned for food, use transitional If patient is to be weaned for food, use transitional

diets (easily digested), starting with clear liquid.diets (easily digested), starting with clear liquid.

Nutritional Recovery Nutritional Recovery Syndrome Syndrome

The nutritional recovery syndrome, (px is The nutritional recovery syndrome, (px is fedd aggressively) sometimes called the fedd aggressively) sometimes called the refeeding syndrome, results from overly refeeding syndrome, results from overly aggressively feeding patients who are aggressively feeding patients who are severely malnourished or who haven't severely malnourished or who haven't eaten in a long period of time. eaten in a long period of time.

Refeeding a starved person results in a Refeeding a starved person results in a shift of potassium and phosphorus into shift of potassium and phosphorus into the body's cells for ATP production, the body's cells for ATP production, which can result in electrolyte imbalance. which can result in electrolyte imbalance. Therefore, refeeding a severely Therefore, refeeding a severely malnourished patient should occur malnourished patient should occur gradually, and the patient should be gradually, and the patient should be monitored closely. monitored closely.

Calculation of Protein Calculation of Protein Content Content

To calculate the grams of protein supplied by a To calculate the grams of protein supplied by a TPN solution, multiply the total volume of TPN solution, multiply the total volume of amino acid solution (in ml*) supplied in a day amino acid solution (in ml*) supplied in a day by the amino acid concentration. by the amino acid concentration. Note:Note:

If the total volume of AA is not stated in the If the total volume of AA is not stated in the prescription, you can calculate it. Just multiply the prescription, you can calculate it. Just multiply the rate of infusion of AA by 24 hr.rate of infusion of AA by 24 hr.

*Remember that 1 ml = 1 cc.*Remember that 1 ml = 1 cc.

Example Protein Calculation Example Protein Calculation

1000 ml of 8% amino acids 1000 ml x 8 1000 ml of 8% amino acids 1000 ml x 8 g/100 ml = 80g g/100 ml = 80g

Practice: Practice:

1.1. 1.5 L; 5% AA 1.5 L; 5% AA

2.2. 0.75 L; 7% AA 0.75 L; 7% AA

3.3. 1.0 L; 3.5% AA 1.0 L; 3.5% AA

4.4. 1.25 L; 8.5% AA 1.25 L; 8.5% AA

Calculation of Dextrose Calculation of Dextrose Content Content

To determine kcalories supplied from dextrose To determine kcalories supplied from dextrose in the TPN solution, you must first calculate in the TPN solution, you must first calculate grams of dextrose. Multiply the total volume of grams of dextrose. Multiply the total volume of dextrose soln (in ml) supplied in a day by the dextrose soln (in ml) supplied in a day by the dextrose concentration. This gives you grams dextrose concentration. This gives you grams of dextrose supplied in a day. Multiply the of dextrose supplied in a day. Multiply the grams of dextrose by 3.4 (there are 3.4 kcal/g grams of dextrose by 3.4 (there are 3.4 kcal/g dextrose) to determine kcalories supplied by dextrose) to determine kcalories supplied by dextrose in a day. dextrose in a day.

Note:Note: If the total dextrose volume is not stated in If the total dextrose volume is not stated in the prescription, you can calculate it. Just the prescription, you can calculate it. Just multiply the rate of infusion of dextrose by 24 multiply the rate of infusion of dextrose by 24 hr.hr.

*Remember that 1 ml = 1 cc.*Remember that 1 ml = 1 cc.

Example Dextrose Calculation Example Dextrose Calculation

1000 ml of D50W 1000 ml x 50g / 100 ml 1000 ml of D50W 1000 ml x 50g / 100 ml = 500g dex= 500g dex

500g dex x 3.4 kcal/g = 1700 kcal 500g dex x 3.4 kcal/g = 1700 kcal

Practice:Practice:

1.1. 1.5 L D50W= g? kcal?1.5 L D50W= g? kcal?

2.2. 0.75 L D70W 0.75 L D70W

3.3. 1.0 L D40W 1.0 L D40W

4.4. 1.25 L D30W 1.25 L D30W

Calculation of Lipid Calculation of Lipid Content Content

Since lipid emulsions contain glycerol, Since lipid emulsions contain glycerol, the lipid emulsion does not have 9 kcal the lipid emulsion does not have 9 kcal per gram* as it would if it were pure fat. per gram* as it would if it were pure fat. To determine kcalories supplied by lipid, To determine kcalories supplied by lipid, multiply the volume of 10% lipid (in ml) by multiply the volume of 10% lipid (in ml) by 1.1; multiply the volume of 20% lipid (in 1.1; multiply the volume of 20% lipid (in ml) by 2.0. ml) by 2.0.

If lipids are not given daily, divide total If lipids are not given daily, divide total kcalories supplied by fat in one week by kcalories supplied by fat in one week by 7 to get an estimate of the average fat 7 to get an estimate of the average fat kcalories per day. kcalories per day. *Note: Some use 10 kcal/gm for lipid *Note: Some use 10 kcal/gm for lipid

emulsions.emulsions.

Example Lipid Calculation Example Lipid Calculation

500 ml of 10% lipid 500 ml x 1.1 kcal/ml = 500 ml of 10% lipid 500 ml x 1.1 kcal/ml = 550 kcal 550 kcal

500 ml 20% lipid 500 ml x 2.0 kcal/ml = 500 ml 20% lipid 500 ml x 2.0 kcal/ml = 1000 kcal 1000 kcal

Practice:Practice:

1.1. 1.5 L 10% lipid 1.5 L 10% lipid

2.2. 0.75 L 10% lipid 0.75 L 10% lipid

3.3. 0.5 L 20% lipid 0.5 L 20% lipid

4.4. 1.25 L 20% lipid 1.25 L 20% lipid

Calculation of Nonprotein Calculation of Nonprotein Calories Calories

To determine the nonprotein kcalories To determine the nonprotein kcalories (NPC) supplied per day in a TPN (NPC) supplied per day in a TPN prescription, add the kcalories supplied prescription, add the kcalories supplied per day from dextrose with the kcalories per day from dextrose with the kcalories supplied per day from lipid emulsion. supplied per day from lipid emulsion.

Example NPC Calculation Example NPC Calculation

1000 ml/d D50W = 1700 kcal/d 500 ml/d 1000 ml/d D50W = 1700 kcal/d 500 ml/d 10% lipid = 550 kcal/d10% lipid = 550 kcal/d

1700 + 550 = 2200 nonprotein kcals per 1700 + 550 = 2200 nonprotein kcals per day day

Practice:Practice:

1.1. 1.5 L D50W; 500 mL 10% lipid 1.5 L D50W; 500 mL 10% lipid

2.2. 0.75 L D70W; 250 mL 10% lipid 0.75 L D70W; 250 mL 10% lipid

3.3. 1.0 L D40W; 500 mL 20% lipid 1.0 L D40W; 500 mL 20% lipid

4.4. 1.25 L D30W; 250 mL 20% lipid 1.25 L D30W; 250 mL 20% lipid

Calculation of NPC:N Calculation of NPC:N Ratio Ratio

The nonprotein kcalorie to nitrogen ratio The nonprotein kcalorie to nitrogen ratio (NPC:N) is calculated as follows: (NPC:N) is calculated as follows:

1. Calculate grams of nitrogen supplied 1. Calculate grams of nitrogen supplied per day (1 g N = 6.25g protein) per day (1 g N = 6.25g protein)

2. Divide total nonprotein kcalories by 2. Divide total nonprotein kcalories by grams of nitrogen grams of nitrogen

Desireable NPC:N RatiosDesireable NPC:N Ratios

80:1 the most severely stressed patients 80:1 the most severely stressed patients

100:1 severely stressed patients 100:1 severely stressed patients

150:1 unstressed patient150:1 unstressed patient

Example NPC:N Calculation Example NPC:N Calculation

80 grams protein80 grams protein

2250 nonprotein kcalories per day 80g 2250 nonprotein kcalories per day 80g protein/ 6.25 = 12.8protein/ 6.25 = 12.82250/12.8 = 1762250/12.8 = 176NPC:N = 176:1 NPC:N = 176:1

Practice:Practice:

1.1. 2000 kcal; 90 g protein 2000 kcal; 90 g protein

2.2. 2250 kcal; 75 g protein 2250 kcal; 75 g protein

3.3. 1800 kcal; 105 g protein 1800 kcal; 105 g protein

4.4. 3300 kcal; 120 g protein 3300 kcal; 120 g protein

Calculation of %NPC from Calculation of %NPC from Fat Fat

As fewer than 60% of a patient's As fewer than 60% of a patient's nonprotein kcals should be from fat in nonprotein kcals should be from fat in order to prevent hyperlipidemia, it is order to prevent hyperlipidemia, it is important to calculate the percent of non important to calculate the percent of non protein kcals from fat. protein kcals from fat.

To determine the percent of nonprotein To determine the percent of nonprotein kcals from fat, divide the kcals/d from fat kcals from fat, divide the kcals/d from fat by the total nonprotein kcal/d and multiply by the total nonprotein kcal/d and multiply by 100by 100

Example %NPC Fat Calculation Example %NPC Fat Calculation

2250 nonprotein kcal2250 nonprotein kcal

550 lipid kcal 550/2250 x 100 = 24% fat 550 lipid kcal 550/2250 x 100 = 24% fat kcalskcals

AcceptableAcceptable

PracticePractice

1.1. 2000 total kcal; 550 lipid kcal= %2000 total kcal; 550 lipid kcal= %

2.2. 2250 total kcal; 500 lipid kcal 2250 total kcal; 500 lipid kcal

3.3. 1800 total kcal; 250 lipid kcal 1800 total kcal; 250 lipid kcal

4.4. 3300 total kcal; 1100 lipid kcal 3300 total kcal; 1100 lipid kcal

Calculation of Solution Calculation of Solution Osmolarity Osmolarity

The maximum The maximum osmolarityosmolarity tolerated by tolerated by PPN is 900-1100 mOsm/L. Therefore, it PPN is 900-1100 mOsm/L. Therefore, it is important to calculate the osmolarity of is important to calculate the osmolarity of the PPN solution. Remember that lipids the PPN solution. Remember that lipids do not contribute to the osmolarity of the do not contribute to the osmolarity of the solutionsolution

To calculate solution osmolarity:To calculate solution osmolarity:

1. multiply grams of dextrose per liter by 5 1. multiply grams of dextrose per liter by 5

2. multiply grams of protein per liter by 10 2. multiply grams of protein per liter by 10

3. add a & b 3. add a & b

4. add 300 to 400 to the answer from "c". 4. add 300 to 400 to the answer from "c". (Vitamins and minerals contribute about (Vitamins and minerals contribute about 300 to 400 mOsm/L.) 300 to 400 mOsm/L.)

Example Osmolarity Calculation Example Osmolarity Calculation 1 L D50W (500 g dex/L)1 L D50W (500 g dex/L)

1 L 8% AA (80 g AA/L) 500 g x 5 = 2500 1 L 8% AA (80 g AA/L) 500 g x 5 = 2500 mOsmmOsm80 g x 10 = 800 mOsm80 g x 10 = 800 mOsm

2500 + 800 = 3300 mOsm/L3300 + 300 2500 + 800 = 3300 mOsm/L3300 + 300 to 400 = 3600 to 3700mOsm/Lto 400 = 3600 to 3700mOsm/L

The prescription is not suitable for The prescription is not suitable for PPNPPN

Practice:Practice:

1.1. 1.5 L D50W; 0.5 L 10% AA 1.5 L D50W; 0.5 L 10% AA

2.2. 0.75 L D70W; 0.75 L 5% AA 0.75 L D70W; 0.75 L 5% AA

3.3. 1.0 L D40W; 1.0 L 3.5% AA 1.0 L D40W; 1.0 L 3.5% AA

4.4. 1.25 L D30W; 1.0 L 3% AA 1.25 L D30W; 1.0 L 3% AA

*Assume vitamin/minerals contribute 350 *Assume vitamin/minerals contribute 350 mOsm/LmOsm/L

Determination of Determination of EFA Adequacy EFA Adequacy

To determine if essential fatty acid (EFA) To determine if essential fatty acid (EFA) needs are met by the TPN prescription, needs are met by the TPN prescription, you must know the percentage of EFA in you must know the percentage of EFA in the lipid emulsion. This information is the lipid emulsion. This information is supplied by the manufacturer. Most lipid supplied by the manufacturer. Most lipid emulsions are at least 50% EFA. emulsions are at least 50% EFA.

Multiply the total kcalories of lipid the Multiply the total kcalories of lipid the patient receives in a day by the percent patient receives in a day by the percent of EFA in the emulsion. Compare this to of EFA in the emulsion. Compare this to the patients EFA requirement (2-4% of the patients EFA requirement (2-4% of kcals). kcals).

Example EFA Calculation Example EFA Calculation

2250 kcals/d2250 kcals/d550 kcal 10% lipid (50% EFA) 550 kcal x 50% 550 kcal 10% lipid (50% EFA) 550 kcal x 50% = 275 kcal EFA= 275 kcal EFA

275/2250 x 100 = 12% EFA275/2250 x 100 = 12% EFA

EFA needs are being metEFA needs are being met

Practice:Practice:

1.1. 2000 total kcal; 500 mL 10% lipid 2000 total kcal; 500 mL 10% lipid

2.2. 2250 total kcal; 500 mL 20% lipid 2250 total kcal; 500 mL 20% lipid

Determination of Fluid Determination of Fluid Needs Needs

luid needs for an individual can be luid needs for an individual can be calculated as 1 ml/kcal or 35 ml/kg usual calculated as 1 ml/kcal or 35 ml/kg usual body weight (UBW). body weight (UBW).

Patients who have large water losses Patients who have large water losses through perspiration or oozing wounds through perspiration or oozing wounds may require more fluids.may require more fluids.

Calculation of Fluid Calculation of Fluid NeedsNeeds

In general, adults need 35 mL water per kg In general, adults need 35 mL water per kg body weight, children need 70 -100 mL/kg, and body weight, children need 70 -100 mL/kg, and infants need 150 mL/kg. infants need 150 mL/kg.

Fluid needs are increased with excessive Fluid needs are increased with excessive sweating, vomiting, diarrhea, or tube drainage.sweating, vomiting, diarrhea, or tube drainage.

Fluids are restricted in certain disease states Fluids are restricted in certain disease states such as renal failure and congestive heart such as renal failure and congestive heart failurefailure

Example Fluid Needs Calculation Example Fluid Needs Calculation 70 kg man: 70 kg man:

35 mL/kg x 70 kg = 2450 mL/d35 mL/kg x 70 kg = 2450 mL/d 30 kg child: 30 kg child:

70 to 100 mL/kg x 30 kg = 2100 to 3000 70 to 100 mL/kg x 30 kg = 2100 to 3000 mL/dmL/d

5 kg infant: 5 kg infant:

150 mL/kg x 5 kg = 750 mL/d150 mL/kg x 5 kg = 750 mL/d

Obligatory Fluid Output Obligatory Fluid Output

One way to assess the appropriateness One way to assess the appropriateness of fluid intake is to monitor the patient's of fluid intake is to monitor the patient's urine output. urine output.

Obligatory fluid output is the minimum Obligatory fluid output is the minimum output of urine necessary to remove output of urine necessary to remove wastes and is estimated to be roughly wastes and is estimated to be roughly 700 mL per day or 30 mL per hour.700 mL per day or 30 mL per hour.

Monitoring Hydration Monitoring Hydration StatusStatus

Hydration status can be monitored via Hydration status can be monitored via daily weights, hematocrit, blood urea daily weights, hematocrit, blood urea nitrogen (BUN), and electrolyte levels. nitrogen (BUN), and electrolyte levels.

High values for the above parametres High values for the above parametres indicate dehydration. Also, a weight indicate dehydration. Also, a weight change of 2.2 pounds repesents 1 L of change of 2.2 pounds repesents 1 L of fluid if the weight change is due entirely fluid if the weight change is due entirely to fluid loss or gain. to fluid loss or gain.

Nutritional assessment indicators of Nutritional assessment indicators of protein status can be used to determine protein status can be used to determine adequacy of protein intake, and weight adequacy of protein intake, and weight can be used to determine adequacy of can be used to determine adequacy of kcalories, unless the patient is retaining kcalories, unless the patient is retaining fluid. fluid.

Calculation of Calculation of PN Prescription PN Prescription

There are different ways to calculate There are different ways to calculate parenteral nutrition prescriptions to meet parenteral nutrition prescriptions to meet the patient's nutritional needs. the patient's nutritional needs.

Standard or "ready-mixed" bags of Standard or "ready-mixed" bags of dextrose and amino acid solutions exist dextrose and amino acid solutions exist and are used for some patients.and are used for some patients.

TPN prescriptions can be calculated and TPN prescriptions can be calculated and compounded to meet the patient's compounded to meet the patient's specific nutritional needs precisely. Two specific nutritional needs precisely. Two methods for calculating TPN solutions methods for calculating TPN solutions follow. follow.

Dex/AA with Piggyback Dex/AA with Piggyback Lipids Lipids

Determine patient's kcalorie, protein, and fluid Determine patient's kcalorie, protein, and fluid needs. needs.

Determine lipid volume and rate for "piggy Determine lipid volume and rate for "piggy back" administration. back" administration. Determine kcals to be supplied from lipid. (Usually Determine kcals to be supplied from lipid. (Usually

30% of total kcals). 30% of total kcals). Divide lipid kcals by 1.1 kcal/cc if you are using 10% Divide lipid kcals by 1.1 kcal/cc if you are using 10%

lipids; divide lipid kcals by 2 kcal/cc if you are using lipids; divide lipid kcals by 2 kcal/cc if you are using 20% lipids. This is the total volume. 20% lipids. This is the total volume.

Divide total volume of lipid by 24 hr to determine Divide total volume of lipid by 24 hr to determine rate in cc/hr. rate in cc/hr.

Determine protein concentration. Determine protein concentration. Subtract volume of lipid from fluid Subtract volume of lipid from fluid

requirement to determine remaining fluid requirement to determine remaining fluid needs. needs.

Divide protein requirement (in grams) by Divide protein requirement (in grams) by remaining fluid requirement and multiply by remaining fluid requirement and multiply by 100. This gives you the amino acid 100. This gives you the amino acid concentration in %. concentration in %.

Determine dextrose concentration. Determine dextrose concentration. Subtract kcals of lipid from total kcals to Subtract kcals of lipid from total kcals to

determine remaining kcal needs. determine remaining kcal needs. Divide "remaining kcals" by 3.4 kcal/g to Divide "remaining kcals" by 3.4 kcal/g to

determine grams of dextrose. determine grams of dextrose. Divide dextrose grams by remaining fluid Divide dextrose grams by remaining fluid

needs (see 3a) and multiply by 100 to needs (see 3a) and multiply by 100 to determine dextrose concentration. determine dextrose concentration.

Determine rate of AA/dex solution by Determine rate of AA/dex solution by dividing "remaining fluid needs by 24 hr. dividing "remaining fluid needs by 24 hr.

Example CalculationExample Calculation Nutrient Needs: Nutrient Needs:

Kcals: 1800 Protein: 88 g Fluid: 2000 cc Kcals: 1800 Protein: 88 g Fluid: 2000 cc

Lipid (10%): 1800 kcal x 30% = 540 kcal Lipid (10%): 1800 kcal x 30% = 540 kcal 540 kcal 540 kcal 1.1 kcal/cc = 491 cc/24hr =1.1 kcal/cc = 491 cc/24hr =

20 cc/hr 10% lipid 20 cc/hr 10% lipid

Remaining fluid needs: 2000cc - 491cc = 1509cc Remaining fluid needs: 2000cc - 491cc = 1509cc Remaining kcal needs: 1800 - 540 = 1260 kcal Remaining kcal needs: 1800 - 540 = 1260 kcal Protein: 88 g / 1509 cc x 100 = 5.8% amino acid solution Protein: 88 g / 1509 cc x 100 = 5.8% amino acid solution

Dextrose: 1260 kcal/ Dextrose: 1260 kcal/ 3.4 kcal/g = 371 g dex 3.4 kcal/g = 371 g dex

371 g / 1509 cc x 100 = 24.6% dextrose 371 g / 1509 cc x 100 = 24.6% dextrose solution solution

Rate of Amino Acid / Dextrose: 1509 cc / Rate of Amino Acid / Dextrose: 1509 cc / 24hr = 63 cc/hr 24hr = 63 cc/hr

Practice:Practice:

1. 1. Nutrient Needs:Nutrient Needs: Kcal: 3000 Kcal: 3000 Protein: 120 g Protein: 120 g Fluid 2800 cc Fluid 2800 cc

20% lipid emulsion at 30% of kcals20% lipid emulsion at 30% of kcals

Lipid kcals provided= ?Lipid kcals provided= ?

Volume of solution=?Volume of solution=?

Rate of administration= ?Rate of administration= ?

Unmet Needs:Unmet Needs:

Remaining kcals: Remaining kcals:

Remaining Fluid: Remaining Fluid:

Protein Concentration: Protein Concentration:

Grams of Dextrose: Grams of Dextrose: Dextrose Concentration: Dextrose Concentration: Rate of AA/Dex solution administration: Rate of AA/Dex solution administration:

3 in 1 TNA Solutions 3 in 1 TNA Solutions Determine patient's kcalorie, protein, and fluid Determine patient's kcalorie, protein, and fluid

needs. needs. Divide daily fluid need by 24 to determine Divide daily fluid need by 24 to determine

rate of administration. rate of administration. Determine lipid concentration. Determine lipid concentration.

Determine kcals to be supplied from lipid. (Usually Determine kcals to be supplied from lipid. (Usually 30% of total kcals). 30% of total kcals).

Determine grams of lipid by dividing kcal lipid by 9. Determine grams of lipid by dividing kcal lipid by 9.

Divide lipid grams by total daily volume (= fluid Divide lipid grams by total daily volume (= fluid needs or final rate x 24) and multiply by 100 to needs or final rate x 24) and multiply by 100 to determine %lipid. determine %lipid.

Determine protein concentration by Determine protein concentration by dividing protein needs (grams) by total dividing protein needs (grams) by total daily volume and multiply by 100. daily volume and multiply by 100.

Determine dextrose grams. Determine dextrose grams. Subtract kcals of lipid from total kcals to Subtract kcals of lipid from total kcals to

determine remaining kcal needs. determine remaining kcal needs. Divide "remaining kcals" by 3.4 kcal/g to Divide "remaining kcals" by 3.4 kcal/g to

determine grams of dextrose. determine grams of dextrose.

Determine dextrose concentration by Determine dextrose concentration by dividing dextrose grams by total daily dividing dextrose grams by total daily volume and multiply by 100. volume and multiply by 100.

Example Calculation Example Calculation

Nutrient Needs:Nutrient Needs:

Kcals: 1800 Protein: 88 g Fluid: 2000 cc Kcals: 1800 Protein: 88 g Fluid: 2000 cc

   

Lipid (10%): 1800 kcal x 30% = 540 kcal Lipid (10%): 1800 kcal x 30% = 540 kcal 540 kcal / 9 kcal per gram = 60 g540 kcal / 9 kcal per gram = 60 g

60 g / 2000 cc x 100 = 3% lipid60 g / 2000 cc x 100 = 3% lipid

Protein: 88 g / 2000 cc x 100 = 4.4% amino Protein: 88 g / 2000 cc x 100 = 4.4% amino acid solution acid solution

Dextrose: 1260 kcal Dextrose: 1260 kcal 3.4 kcal/g = 371 g dex3.4 kcal/g = 371 g dex 371 g / 2000 cc x 100 = 18.6% dextrose solution 371 g / 2000 cc x 100 = 18.6% dextrose solution

Rate of Amino Acid / Dextrose: 2000 cc / 24hr Rate of Amino Acid / Dextrose: 2000 cc / 24hr = 83 cc/hr= 83 cc/hr

Calculation of Additional Calculation of Additional Water Needs Water Needs

When using standard or "ready-made" TPN When using standard or "ready-made" TPN solutions, you need to ensure that fluid needs solutions, you need to ensure that fluid needs are being met. To determine the additional are being met. To determine the additional sterile water prescription for the TPN solution, sterile water prescription for the TPN solution, you need to know the patient's fluid needs. you need to know the patient's fluid needs.

Subtract volume of TPN solution provided in a Subtract volume of TPN solution provided in a day from the fluid requirement. The difference day from the fluid requirement. The difference is the volume of sterile water that should be is the volume of sterile water that should be added to the TPN solution.added to the TPN solution.

Example Water Rx Calculation Example Water Rx Calculation

Fluid needs = 2450 ml/d TPN Rx Fluid needs = 2450 ml/d TPN Rx provides 2000 ml fluid per dayprovides 2000 ml fluid per day

2450 ml - 2000 ml = 450 ml additional 2450 ml - 2000 ml = 450 ml additional sterile water needed sterile water needed

Calculation of Fluid Calculation of Fluid Needs Needs

In general, adults need 35 mL water per kg In general, adults need 35 mL water per kg body weight, children need 70 -100 mL/kg, and body weight, children need 70 -100 mL/kg, and infants need 150 mL/kg. infants need 150 mL/kg.

Fluid needs are increased with excessive Fluid needs are increased with excessive sweating, vomiting, diarrhea, or tube drainage.sweating, vomiting, diarrhea, or tube drainage.

Fluids are restricted in certain disease states Fluids are restricted in certain disease states such as renal failure and congestive heart such as renal failure and congestive heart failurefailure

Example Fluid Needs Calculation Example Fluid Needs Calculation 70 kg man: 70 kg man:

35 mL/kg x 70 kg = 2450 mL/d35 mL/kg x 70 kg = 2450 mL/d 30 kg child: 30 kg child:

70 to 100 mL/kg x 30 kg = 2100 to 3000 70 to 100 mL/kg x 30 kg = 2100 to 3000 mL/dmL/d

5 kg infant: 5 kg infant: 150 mL/kg x 5 kg = 750 mL/d150 mL/kg x 5 kg = 750 mL/d